for Journals by Title or ISSN
for Articles by Keywords
help

Publisher: John Wiley and Sons   (Total: 1579 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

        1 2 3 4 5 6 7 8 | Last   [Sort by number of followers]   [Restore default list]

Showing 1 - 200 of 1579 Journals sorted alphabetically
Abacus     Hybrid Journal   (Followers: 12, SJR: 0.48, h-index: 22)
About Campus     Hybrid Journal   (Followers: 5)
Academic Emergency Medicine     Hybrid Journal   (Followers: 65, SJR: 1.385, h-index: 91)
Accounting & Finance     Hybrid Journal   (Followers: 46, SJR: 0.547, h-index: 30)
ACEP NOW     Free   (Followers: 1)
Acta Anaesthesiologica Scandinavica     Hybrid Journal   (Followers: 51, SJR: 1.02, h-index: 88)
Acta Archaeologica     Hybrid Journal   (Followers: 152, SJR: 0.101, h-index: 9)
Acta Geologica Sinica (English Edition)     Hybrid Journal   (Followers: 3, SJR: 0.552, h-index: 41)
Acta Neurologica Scandinavica     Hybrid Journal   (Followers: 5, SJR: 1.203, h-index: 74)
Acta Obstetricia et Gynecologica Scandinavica     Hybrid Journal   (Followers: 15, SJR: 1.197, h-index: 81)
Acta Ophthalmologica     Hybrid Journal   (Followers: 5, SJR: 0.112, h-index: 1)
Acta Paediatrica     Hybrid Journal   (Followers: 56, SJR: 0.794, h-index: 88)
Acta Physiologica     Hybrid Journal   (Followers: 6, SJR: 1.69, h-index: 88)
Acta Polymerica     Hybrid Journal   (Followers: 9)
Acta Psychiatrica Scandinavica     Hybrid Journal   (Followers: 35, SJR: 2.518, h-index: 113)
Acta Zoologica     Hybrid Journal   (Followers: 6, SJR: 0.459, h-index: 29)
Acute Medicine & Surgery     Hybrid Journal   (Followers: 4)
Addiction     Hybrid Journal   (Followers: 35, SJR: 2.086, h-index: 143)
Addiction Biology     Hybrid Journal   (Followers: 13, SJR: 2.091, h-index: 57)
Adultspan J.     Hybrid Journal   (SJR: 0.127, h-index: 4)
Advanced Energy Materials     Hybrid Journal   (Followers: 26, SJR: 6.411, h-index: 86)
Advanced Engineering Materials     Hybrid Journal   (Followers: 26, SJR: 0.81, h-index: 81)
Advanced Functional Materials     Hybrid Journal   (Followers: 50, SJR: 5.21, h-index: 203)
Advanced Healthcare Materials     Hybrid Journal   (Followers: 13, SJR: 0.232, h-index: 7)
Advanced Materials     Hybrid Journal   (Followers: 259, SJR: 9.021, h-index: 345)
Advanced Materials Interfaces     Hybrid Journal   (Followers: 6, SJR: 1.177, h-index: 10)
Advanced Optical Materials     Hybrid Journal   (Followers: 5, SJR: 2.488, h-index: 21)
Advanced Science     Open Access   (Followers: 5)
Advanced Synthesis & Catalysis     Hybrid Journal   (Followers: 17, SJR: 2.729, h-index: 121)
Advances in Polymer Technology     Hybrid Journal   (Followers: 13, SJR: 0.344, h-index: 31)
Africa Confidential     Hybrid Journal   (Followers: 19)
Africa Research Bulletin: Economic, Financial and Technical Series     Hybrid Journal   (Followers: 12)
Africa Research Bulletin: Political, Social and Cultural Series     Hybrid Journal   (Followers: 9)
African Development Review     Hybrid Journal   (Followers: 34, SJR: 0.275, h-index: 17)
African J. of Ecology     Hybrid Journal   (Followers: 15, SJR: 0.477, h-index: 39)
Aggressive Behavior     Hybrid Journal   (Followers: 15, SJR: 1.391, h-index: 66)
Aging Cell     Open Access   (Followers: 10, SJR: 4.374, h-index: 95)
Agribusiness : an Intl. J.     Hybrid Journal   (Followers: 6, SJR: 0.627, h-index: 14)
Agricultural and Forest Entomology     Hybrid Journal   (Followers: 16, SJR: 0.925, h-index: 43)
Agricultural Economics     Hybrid Journal   (Followers: 45, SJR: 1.099, h-index: 51)
AIChE J.     Hybrid Journal   (Followers: 30, SJR: 1.122, h-index: 120)
Alcoholism and Drug Abuse Weekly     Hybrid Journal   (Followers: 7)
Alcoholism Clinical and Experimental Research     Hybrid Journal   (Followers: 7, SJR: 1.416, h-index: 125)
Alimentary Pharmacology & Therapeutics     Hybrid Journal   (Followers: 33, SJR: 2.833, h-index: 138)
Alimentary Pharmacology & Therapeutics Symposium Series     Hybrid Journal   (Followers: 3)
Allergy     Hybrid Journal   (Followers: 50, SJR: 3.048, h-index: 129)
Alternatives to the High Cost of Litigation     Hybrid Journal   (Followers: 3)
American Anthropologist     Hybrid Journal   (Followers: 140, SJR: 0.951, h-index: 61)
American Business Law J.     Hybrid Journal   (Followers: 24, SJR: 0.205, h-index: 17)
American Ethnologist     Hybrid Journal   (Followers: 90, SJR: 2.325, h-index: 51)
American J. of Economics and Sociology     Hybrid Journal   (Followers: 28, SJR: 0.211, h-index: 26)
American J. of Hematology     Hybrid Journal   (Followers: 33, SJR: 1.761, h-index: 77)
American J. of Human Biology     Hybrid Journal   (Followers: 12, SJR: 1.018, h-index: 58)
American J. of Industrial Medicine     Hybrid Journal   (Followers: 16, SJR: 0.993, h-index: 85)
American J. of Medical Genetics Part A     Hybrid Journal   (Followers: 16, SJR: 1.115, h-index: 61)
American J. of Medical Genetics Part B: Neuropsychiatric Genetics     Hybrid Journal   (Followers: 4, SJR: 1.771, h-index: 107)
American J. of Medical Genetics Part C: Seminars in Medical Genetics     Partially Free   (Followers: 6, SJR: 2.315, h-index: 79)
American J. of Physical Anthropology     Hybrid Journal   (Followers: 37, SJR: 1.41, h-index: 88)
American J. of Political Science     Hybrid Journal   (Followers: 269, SJR: 5.101, h-index: 114)
American J. of Primatology     Hybrid Journal   (Followers: 15, SJR: 1.197, h-index: 63)
American J. of Reproductive Immunology     Hybrid Journal   (Followers: 3, SJR: 1.347, h-index: 75)
American J. of Transplantation     Hybrid Journal   (Followers: 17, SJR: 2.792, h-index: 140)
American J. on Addictions     Hybrid Journal   (Followers: 9, SJR: 0.843, h-index: 57)
Anaesthesia     Hybrid Journal   (Followers: 130, SJR: 1.404, h-index: 88)
Analyses of Social Issues and Public Policy     Hybrid Journal   (Followers: 10, SJR: 0.397, h-index: 18)
Analytic Philosophy     Hybrid Journal   (Followers: 16)
Anatomia, Histologia, Embryologia: J. of Veterinary Medicine Series C     Hybrid Journal   (Followers: 3, SJR: 0.295, h-index: 27)
Anatomical Sciences Education     Hybrid Journal   (Followers: 1, SJR: 0.633, h-index: 24)
Andrologia     Hybrid Journal   (Followers: 2, SJR: 0.528, h-index: 45)
Andrology     Hybrid Journal   (Followers: 2, SJR: 0.979, h-index: 14)
Angewandte Chemie     Hybrid Journal   (Followers: 168)
Angewandte Chemie Intl. Edition     Hybrid Journal   (Followers: 215, SJR: 6.229, h-index: 397)
Animal Conservation     Hybrid Journal   (Followers: 38, SJR: 1.576, h-index: 62)
Animal Genetics     Hybrid Journal   (Followers: 8, SJR: 0.957, h-index: 67)
Animal Science J.     Hybrid Journal   (Followers: 6, SJR: 0.569, h-index: 24)
Annalen der Physik     Hybrid Journal   (Followers: 5, SJR: 1.46, h-index: 40)
Annals of Anthropological Practice     Partially Free   (Followers: 2, SJR: 0.187, h-index: 5)
Annals of Applied Biology     Hybrid Journal   (Followers: 7, SJR: 0.816, h-index: 56)
Annals of Clinical and Translational Neurology     Open Access   (Followers: 1)
Annals of Human Genetics     Hybrid Journal   (Followers: 9, SJR: 1.191, h-index: 67)
Annals of Neurology     Hybrid Journal   (Followers: 47, SJR: 5.584, h-index: 241)
Annals of Noninvasive Electrocardiology     Hybrid Journal   (Followers: 2, SJR: 0.531, h-index: 38)
Annals of Public and Cooperative Economics     Hybrid Journal   (Followers: 9, SJR: 0.336, h-index: 23)
Annals of the New York Academy of Sciences     Hybrid Journal   (Followers: 5, SJR: 2.389, h-index: 189)
Annual Bulletin of Historical Literature     Hybrid Journal   (Followers: 13)
Annual Review of Information Science and Technology     Hybrid Journal   (Followers: 14)
Anthropology & Education Quarterly     Hybrid Journal   (Followers: 25, SJR: 0.72, h-index: 31)
Anthropology & Humanism     Hybrid Journal   (Followers: 17, SJR: 0.137, h-index: 3)
Anthropology News     Hybrid Journal   (Followers: 15)
Anthropology of Consciousness     Hybrid Journal   (Followers: 11, SJR: 0.172, h-index: 5)
Anthropology of Work Review     Hybrid Journal   (Followers: 11, SJR: 0.256, h-index: 5)
Anthropology Today     Hybrid Journal   (Followers: 90, SJR: 0.545, h-index: 15)
Antipode     Hybrid Journal   (Followers: 47, SJR: 2.212, h-index: 69)
Anz J. of Surgery     Hybrid Journal   (Followers: 7, SJR: 0.432, h-index: 59)
Anzeiger für Schädlingskunde     Hybrid Journal   (Followers: 1)
Apmis     Hybrid Journal   (Followers: 1, SJR: 0.855, h-index: 73)
Applied Cognitive Psychology     Hybrid Journal   (Followers: 69, SJR: 0.754, h-index: 69)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 7, SJR: 0.632, h-index: 58)
Applied Psychology     Hybrid Journal   (Followers: 177, SJR: 1.023, h-index: 64)
Applied Psychology: Health and Well-Being     Hybrid Journal   (Followers: 49, SJR: 0.868, h-index: 13)
Applied Stochastic Models in Business and Industry     Hybrid Journal   (Followers: 5, SJR: 0.613, h-index: 24)
Aquaculture Nutrition     Hybrid Journal   (Followers: 14, SJR: 1.025, h-index: 55)
Aquaculture Research     Hybrid Journal   (Followers: 31, SJR: 0.807, h-index: 60)
Aquatic Conservation Marine and Freshwater Ecosystems     Hybrid Journal   (Followers: 36, SJR: 1.047, h-index: 57)
Arabian Archaeology and Epigraphy     Hybrid Journal   (Followers: 11, SJR: 0.453, h-index: 11)
Archaeological Prospection     Hybrid Journal   (Followers: 12, SJR: 0.922, h-index: 21)
Archaeology in Oceania     Hybrid Journal   (Followers: 13, SJR: 0.745, h-index: 18)
Archaeometry     Hybrid Journal   (Followers: 27, SJR: 0.809, h-index: 48)
Archeological Papers of The American Anthropological Association     Hybrid Journal   (Followers: 15, SJR: 0.156, h-index: 2)
Architectural Design     Hybrid Journal   (Followers: 25, SJR: 0.261, h-index: 9)
Archiv der Pharmazie     Hybrid Journal   (Followers: 4, SJR: 0.628, h-index: 43)
Archives of Drug Information     Hybrid Journal   (Followers: 4)
Archives of Insect Biochemistry and Physiology     Hybrid Journal   (SJR: 0.768, h-index: 54)
Area     Hybrid Journal   (Followers: 12, SJR: 0.938, h-index: 57)
Art History     Hybrid Journal   (Followers: 237, SJR: 0.153, h-index: 13)
Arthritis & Rheumatology     Hybrid Journal   (Followers: 51, SJR: 1.984, h-index: 20)
Arthritis Care & Research     Hybrid Journal   (Followers: 27, SJR: 2.256, h-index: 114)
Artificial Organs     Hybrid Journal   (Followers: 1, SJR: 0.872, h-index: 60)
ASHE Higher Education Reports     Hybrid Journal   (Followers: 14)
Asia & the Pacific Policy Studies     Open Access   (Followers: 15)
Asia Pacific J. of Human Resources     Hybrid Journal   (Followers: 313, SJR: 0.494, h-index: 19)
Asia Pacific Viewpoint     Hybrid Journal   (Followers: 1, SJR: 0.616, h-index: 26)
Asia-Pacific J. of Chemical Engineering     Hybrid Journal   (Followers: 8, SJR: 0.345, h-index: 20)
Asia-pacific J. of Clinical Oncology     Hybrid Journal   (Followers: 6, SJR: 0.554, h-index: 14)
Asia-Pacific J. of Financial Studies     Hybrid Journal   (SJR: 0.241, h-index: 7)
Asia-Pacific Psychiatry     Hybrid Journal   (Followers: 4, SJR: 0.377, h-index: 7)
Asian Economic J.     Hybrid Journal   (Followers: 8, SJR: 0.234, h-index: 21)
Asian Economic Policy Review     Hybrid Journal   (Followers: 4, SJR: 0.196, h-index: 12)
Asian J. of Control     Hybrid Journal   (SJR: 0.862, h-index: 34)
Asian J. of Endoscopic Surgery     Hybrid Journal   (SJR: 0.394, h-index: 7)
Asian J. of Organic Chemistry     Hybrid Journal   (Followers: 5, SJR: 1.443, h-index: 19)
Asian J. of Social Psychology     Hybrid Journal   (Followers: 5, SJR: 0.665, h-index: 37)
Asian Politics and Policy     Hybrid Journal   (Followers: 12, SJR: 0.207, h-index: 7)
Asian Social Work and Policy Review     Hybrid Journal   (Followers: 5, SJR: 0.318, h-index: 5)
Asian-pacific Economic Literature     Hybrid Journal   (Followers: 5, SJR: 0.168, h-index: 15)
Assessment Update     Hybrid Journal   (Followers: 4)
Astronomische Nachrichten     Hybrid Journal   (Followers: 2, SJR: 0.701, h-index: 40)
Atmospheric Science Letters     Open Access   (Followers: 29, SJR: 1.332, h-index: 27)
Austral Ecology     Hybrid Journal   (Followers: 14, SJR: 1.095, h-index: 66)
Austral Entomology     Hybrid Journal   (Followers: 9, SJR: 0.524, h-index: 28)
Australasian J. of Dermatology     Hybrid Journal   (Followers: 8, SJR: 0.714, h-index: 40)
Australasian J. On Ageing     Hybrid Journal   (Followers: 7, SJR: 0.39, h-index: 22)
Australian & New Zealand J. of Statistics     Hybrid Journal   (Followers: 13, SJR: 0.275, h-index: 28)
Australian Accounting Review     Hybrid Journal   (Followers: 4, SJR: 0.709, h-index: 14)
Australian and New Zealand J. of Family Therapy (ANZJFT)     Hybrid Journal   (Followers: 3, SJR: 0.382, h-index: 12)
Australian and New Zealand J. of Obstetrics and Gynaecology     Hybrid Journal   (Followers: 46, SJR: 0.814, h-index: 49)
Australian and New Zealand J. of Public Health     Hybrid Journal   (Followers: 11, SJR: 0.82, h-index: 62)
Australian Dental J.     Hybrid Journal   (Followers: 7, SJR: 0.482, h-index: 46)
Australian Economic History Review     Hybrid Journal   (Followers: 4, SJR: 0.171, h-index: 12)
Australian Economic Papers     Hybrid Journal   (Followers: 29, SJR: 0.23, h-index: 9)
Australian Economic Review     Hybrid Journal   (Followers: 6, SJR: 0.357, h-index: 21)
Australian Endodontic J.     Hybrid Journal   (Followers: 3, SJR: 0.513, h-index: 24)
Australian J. of Agricultural and Resource Economics     Hybrid Journal   (Followers: 3, SJR: 0.765, h-index: 36)
Australian J. of Grape and Wine Research     Hybrid Journal   (Followers: 5, SJR: 0.879, h-index: 56)
Australian J. of Politics & History     Hybrid Journal   (Followers: 14, SJR: 0.203, h-index: 14)
Australian J. of Psychology     Hybrid Journal   (Followers: 18, SJR: 0.384, h-index: 30)
Australian J. of Public Administration     Hybrid Journal   (Followers: 404, SJR: 0.418, h-index: 29)
Australian J. of Rural Health     Hybrid Journal   (Followers: 5, SJR: 0.43, h-index: 34)
Australian Occupational Therapy J.     Hybrid Journal   (Followers: 71, SJR: 0.59, h-index: 29)
Australian Psychologist     Hybrid Journal   (Followers: 12, SJR: 0.331, h-index: 31)
Australian Veterinary J.     Hybrid Journal   (Followers: 19, SJR: 0.459, h-index: 45)
Autism Research     Hybrid Journal   (Followers: 32, SJR: 2.126, h-index: 39)
Autonomic & Autacoid Pharmacology     Hybrid Journal   (SJR: 0.371, h-index: 29)
Banks in Insurance Report     Hybrid Journal   (Followers: 1)
Basic & Clinical Pharmacology & Toxicology     Hybrid Journal   (Followers: 10, SJR: 0.539, h-index: 70)
Basic and Applied Pathology     Open Access   (Followers: 2, SJR: 0.113, h-index: 4)
Basin Research     Hybrid Journal   (Followers: 5, SJR: 1.54, h-index: 60)
Bauphysik     Hybrid Journal   (Followers: 2, SJR: 0.194, h-index: 5)
Bauregelliste A, Bauregelliste B Und Liste C     Hybrid Journal  
Bautechnik     Hybrid Journal   (Followers: 1, SJR: 0.321, h-index: 11)
Behavioral Interventions     Hybrid Journal   (Followers: 9, SJR: 0.297, h-index: 23)
Behavioral Sciences & the Law     Hybrid Journal   (Followers: 24, SJR: 0.736, h-index: 57)
Berichte Zur Wissenschaftsgeschichte     Hybrid Journal   (Followers: 9, SJR: 0.11, h-index: 5)
Beton- und Stahlbetonbau     Hybrid Journal   (Followers: 2, SJR: 0.493, h-index: 14)
Biochemistry and Molecular Biology Education     Hybrid Journal   (Followers: 6, SJR: 0.311, h-index: 26)
Bioelectromagnetics     Hybrid Journal   (Followers: 1, SJR: 0.568, h-index: 64)
Bioengineering & Translational Medicine     Open Access  
BioEssays     Hybrid Journal   (Followers: 10, SJR: 3.104, h-index: 155)
Bioethics     Hybrid Journal   (Followers: 14, SJR: 0.686, h-index: 39)
Biofuels, Bioproducts and Biorefining     Hybrid Journal   (Followers: 1, SJR: 1.725, h-index: 56)
Biological J. of the Linnean Society     Hybrid Journal   (Followers: 16, SJR: 1.172, h-index: 90)
Biological Reviews     Hybrid Journal   (Followers: 3, SJR: 6.469, h-index: 114)
Biologie in Unserer Zeit (Biuz)     Hybrid Journal   (Followers: 42, SJR: 0.12, h-index: 1)
Biology of the Cell     Full-text available via subscription   (Followers: 9, SJR: 1.812, h-index: 69)
Biomedical Chromatography     Hybrid Journal   (Followers: 6, SJR: 0.572, h-index: 49)
Biometrical J.     Hybrid Journal   (Followers: 5, SJR: 0.784, h-index: 44)
Biometrics     Hybrid Journal   (Followers: 36, SJR: 1.906, h-index: 96)
Biopharmaceutics and Drug Disposition     Hybrid Journal   (Followers: 10, SJR: 0.715, h-index: 44)
Biopolymers     Hybrid Journal   (Followers: 18, SJR: 1.199, h-index: 104)
Biotechnology and Applied Biochemistry     Hybrid Journal   (Followers: 45, SJR: 0.415, h-index: 55)
Biotechnology and Bioengineering     Hybrid Journal   (Followers: 174, SJR: 1.633, h-index: 146)
Biotechnology J.     Hybrid Journal   (Followers: 14, SJR: 1.185, h-index: 51)
Biotechnology Progress     Hybrid Journal   (Followers: 39, SJR: 0.736, h-index: 101)
Biotropica     Hybrid Journal   (Followers: 20, SJR: 1.374, h-index: 71)
Bipolar Disorders     Hybrid Journal   (Followers: 9, SJR: 2.592, h-index: 100)
Birth     Hybrid Journal   (Followers: 37, SJR: 0.763, h-index: 64)
Birth Defects Research Part A : Clinical and Molecular Teratology     Hybrid Journal   (Followers: 2, SJR: 0.727, h-index: 77)
Birth Defects Research Part B: Developmental and Reproductive Toxicology     Hybrid Journal   (Followers: 5, SJR: 0.468, h-index: 47)
Birth Defects Research Part C : Embryo Today : Reviews     Hybrid Journal   (SJR: 1.513, h-index: 55)
BJOG : An Intl. J. of Obstetrics and Gynaecology     Partially Free   (Followers: 233, SJR: 2.083, h-index: 125)

        1 2 3 4 5 6 7 8 | Last   [Sort by number of followers]   [Restore default list]

Journal Cover Advances in Polymer Technology
  [SJR: 0.344]   [H-I: 31]   [13 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0730-6679 - ISSN (Online) 1098-2329
   Published by John Wiley and Sons Homepage  [1579 journals]
  • Toughening of polyamide 12/nanoclay nanocomposites by incompatible
           styrene-butadiene-styrene rubber through tailoring interfacial adhesion
           and fracture mechanism
    • Authors: Ali Naeim Abadi; Hamid Garmabi, Farkhondeh Hemmati
      Abstract: The main drawback of polyamide 12 (PA 12)/nanoclay nanocomposites in their wide range of potential engineering applications known as diminished toughness was overcome using incompatible styrene-butadiene-styrene block copolymer (SBS) rubber. Applying optimal processing parameters for co-rotating twin-screw extrusion resulted in strong interfacial adhesion of matrix and rubber and intercalated and delaminated nanoclay stacks confined in the matrix. The formulation of compatibilized PA 12/SBS/nanoclay nanocomposites was optimized by employing response surface Box–Behnken methodology. A combination of microscopic methods, that is, atomic force microscopy, transmission and scanning electron microscopy, and transmission optical microscopy, along with single-edge-double-notch four-point-bending technique, was exploited to exhaustively explore the toughening mechanisms and microstructure. The findings verify that by tailoring the rubber/matrix interfacial strength and nanocomposite morphology, the Izod impact strength of PA 12/nanoclay nanocomposites is noticeably improved even by incorporating an incompatible rubber and tough fracture mechanisms including rubber particle cavitation and large-scale shear yielding are attained.
      PubDate: 2017-10-17T00:11:10.618641-05:
      DOI: 10.1002/adv.21906
       
  • PAA/alumina composites prepared with different molecular weight polymers
           and utilized as support for nickel-based catalyst
    • Authors: Peng Zhou; Song Wang, ChuanLan Tao, Xingkui Guo, Luhan Hao, Qian Shao, Lei Liu, Ya-Ping Wang, Wei Chu, Bin Wang, Shi-Zhong Luo, Zhanhu Guo
      Abstract: Mesoporous alumina, as a porous, high specific surface area, high activity, and heat stable material, has been widely used as an industrial adsorbent, catalyst, and catalyst support. The modification of alumina with organic polymers has been widely investigated in recent years. In this study, we compared the dependence of the adsorption of a polyelectrolyte, poly(acrylic acid) (PAA) on γ-alumina particles on polymer size via Fourier transform infrared spectroscopy, thermogravimetry, nitrogen adsorption–desorption isotherm analysis, and atomic absorption spectrophotometry. We found that PAA with a hydrodynamic diameter greater than the alumina pore size would only adsorb on the outer surface of the oxides. For polymers with hydrodynamic diameters smaller than the alumina pore size, PAA infiltration resulted in a monolayer coverage of both the outer and inner surfaces of the oxide. Among the three PAA that could infiltrate the alumina pores, the one with the smallest molecular weight showed the highest adsorbed amount on alumina. The temperature, pH, concentration, and ionic strength of the PAA solutions were varied to illustrate the physicochemical differences of the prepared polymer/oxide composite materials. The high PAA-loaded composites were treated with a nickel ion solution, converted to Ni/alumina catalysts, and used in the methanation of carbon dioxide. The Ni/alumina catalysts were analyzed with X-ray diffraction and temperature-programmed reduction to illustrate the structural characteristics. The catalytic CO2 methanation of the catalyst samples revealed that a solution pH value higher than pKa of PAA favored the formation of catalysts with high catalytic activity.
      PubDate: 2017-10-11T00:04:50.157264-05:
      DOI: 10.1002/adv.21908
       
  • Porous wheat gluten microparticles obtained by electrospray: Preparation
           and characterization
    • Authors: José́ A. Tapia-Hernández; Dora E. Rodríguez-Félix, Maribel Plascencia-Jatomea, Agustín Rascón-Chu, Guadalupe A. López-Ahumada, Saúl Ruiz-Cruz, Carlos G. Barreras-Urbina, Francisco Rodríguez-Félix
      Abstract: Currently, microporous polymer materials are being studied extensively due to their attractive properties which allow for a wide potential of applications, such as prolonged-release systems (PRS). The objective of the present work was to prepare and characterize porous microparticles of wheat gluten (WG) using the electrospray technique. The effect of the physicochemical parameters of the solution and electrospray technique parameters on the morphology and size of the materials obtained was studied. For all of the concentrations of WG, porous microparticles with sphere geometry were obtained. At higher concentrations of WG (8% w/v), higher values of viscosity (0.32405 ± 0.002 Pa·s), density (0.997 ± 0.0005 g/cm3), and particle size (1.42 ± 0.71 μm) were obtained, while at lower concentration, high stability rheological is presented, which exhibited Newtonian fluid behavior. Characterization by scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffraction indicated that the material obtained has a potential application in the PRS industry.
      PubDate: 2017-10-10T23:46:07.393281-05:
      DOI: 10.1002/adv.21907
       
  • Mode I interlaminar fracture toughness of carbon-epoxy coupons with
           embedded ceramic sensors
    • Authors: Mauricio Torres; Ricardo A. Tellez, Hilario Hernández, Thierry Camps
      Abstract: This study analyses the mechanical and crack growth behavior of woven carbon fiber reinforced plastics (CPRF) with embedded ceramic sensors. The material studied here is 3K-70-P carbon fiber plain weave with EPOLAM 2015® epoxy resin. The composite is manufactured with vacuum bagging procedure. Later on, the composite Mode I interlaminar fracture toughness (GIC) is calculated by means of double cantilever beam tests (DCB) for two layout configurations [0/90] and [±45] with and without embedded sensors. Results give an initial approach of the fracture behavior of an instrumented composite facing an interlaminar crack. The interlaminar fracture toughness for the instrumented specimens is lower compared to the noninstrumented coupons. The presence of the sensor and its wire connection has a considerable impact on the damage tolerance of the woven composite, where the sensors surroundings seem to be the more likely region to be affected by an interlaminar fracture.
      PubDate: 2017-10-09T09:45:45.297769-05:
      DOI: 10.1002/adv.21905
       
  • The effect of relaxation on the deformation of iPP fiber due to creep
           process
    • Authors: Taha Zaki Nabawy Sokkar; Kermal Ahmed El-Farahaty, Mohammed Ibrahim Raslan, Samar Maher El-Khateep, Ahmed Amin Hamza
      Abstract: In this article, we aim to investigate the effect of relaxation processes on isotactic polypropylene filaments, that is stress relaxation and creep relaxation. In addition, variations of the fiber diameter during creep and relaxation are investigated using laser diffraction technique. Double-image multiple-beam technique and Pluta polarizing interference microscope are used to study the influence of relaxation on necking propagation. Micrographs and interference patterns are given for illustration.
      PubDate: 2017-10-06T02:30:45.824385-05:
      DOI: 10.1002/adv.21879
       
  • Distributive mixing in a corotating twin screw channel using Lagrangian
           particle calculations
    • Authors: Baiping Xu; Huiwen Yu, Lih-Sheng Turng
      Abstract: This work is devoted to the development of a new mapping method for the numerical simulation of melt flow in the complicated forward conveying element of a corotating twin screw extruder under the assumption of periodic boundary conditions of inlet and outlet. The mesh superposition technique (MST) provided by the commercial computational fluid dynamics (CFD) software POLYFLOW was used to deal with the internal moving screw elements, and the flow field of polymer melt obeying the Bird–Carreau constitutive model on the fixed meshes of the flow domain was further solved. After inputting the exported data of the flow field from POLYFLOW, the self-developed code was further used to characterize the mixing behavior at a finite time under different rotation speeds of the screw elements. A novel mapping method was proposed to convert the instantaneous flow field at the initial time point into the velocity field at any time point. Advection evolution of passive particle groups was simulated by a fourth-order Runge–Kutta tracking method, and the corresponding variance index was also calculated. The effect of screw rotation speed on distributive mixing was examined. The results showed that the mixing was highly dependent on the initial position whether the particle groups were first placed close to or far away from the intermeshing zone.
      PubDate: 2017-10-03T23:31:16.973945-05:
      DOI: 10.1002/adv.21880
       
  • Molecularly imprinted polymer membrane for the removal of naphthalene from
           petrochemical wastewater streams
    • Authors: Sahar Ghasemi; Ali Nematollahzadeh
      Abstract: The aim of this work was the preparation of molecularly imprinted membrane (MiM) using polysulfone (PSf) polymer for targeted removal of polycyclic aromatic hydrocarbons from petrochemical wastewater. Naphthalene was opted as a model pollutant, and the imprinted membrane was fabricated by phase inversion technique. Nonimprinted membrane (NiM) was also prepared in the absence of naphthalene and used as a reference. The polymers (MiM/NiM) were systematically characterized using different characterization techniques. The selectivity property of the membranes was evaluated by their ability in separation of naphthalene through filtration tests. Results showed that in comparison with NiM, the imprinted membrane exhibits higher affinity toward naphthalene molecules. It was found that the selectively of MiM is 2.27-fold more than that of the corresponding NiM. This finding can be encouraging from industrial applications points of view.
      PubDate: 2017-09-25T01:06:13.263076-05:
      DOI: 10.1002/adv.21904
       
  • Wear performance of multiwalled carbon nanotube-reinforced ultra-high
           molecular weight polyethylene composite
    • Authors: Nayeli Camacho; Edgar A. Franco-Urquiza, Stephen W. Stafford
      Abstract: Ultra-high molecular weight polyethylene (UHMWPE) has proven to be a good counterpart articulating surface against Cr–Co–Mo femoral components in artificial joints. Nevertheless, UHMWPE wear damage and subsequent aseptic loosening continues to be the main reason for revision of knee replacements. There is an ongoing research effort to improve the metal-on-UHMWPE couple. This study compares the wear resistance of multiwalled carbon nanotube-reinforced UHMWPE composite with conventional orthopedic grade UHMWPE currently used in total knee replacements. Defined by previous studies, 1.25 wt.% multiwall carbon nanotubes (MWCNT) were incorporated into UHMWPE to fabricate UHMWPE-MWCNT composites by solution blending, achieving an even distribution in the polymeric matrix. UHMWPE-MWCNT samples were manufactured by compression molding and sterilized with γ-rays. Scanning electron microscopy confirmed a uniform distribution of the MWCNTs. The volumetric wear was reduced by 86.9%, and the indentation depth in creep testing decreased 68%. The composite displayed superior wear behavior producing less wear debris than conventional materials.
      PubDate: 2017-09-17T23:55:45.753836-05:
      DOI: 10.1002/adv.21885
       
  • The evaluation of stretchability and its applications for biaxially
           oriented polypropylene film
    • Authors: Toshitaka Kanai; Kentaro Egoshi, Satoshi Ohno, Tomoaki Takebe
      Abstract: In recent years, plastic film is essential in our daily lives. Among them, polypropylene has good physical properties, for example, tensile strength, impact strength, and transparency. Recently, it was found that the stretchability of polypropylene (PP) is improved by blending a small amount of low modulus polypropylene (LMPP) which is a low tacticity polypropylene. The purpose of this research was to investigate the effect of blending LMPP, which has different characteristic of resin such as tacticity and molecular weight, on PP and to study the mechanism of the structure formation in a biaxial stretching process. The blending of LMPP to PP reduces the spherulite size and increases the thickness of the amorphous phase in the lamella without changing the thickness of the crystal phase, namely the melting temperature. LMPP blends also reduced the yield stress during the stretching process and increased the stress buildup ratio. For these reasons, it improved film thickness uniformity of biaxially stretched film and reduced film break during the high production line. Furthermore, as the stretchable temperature window was widened to the low-temperature side, the thickness uniformity was improved in the wide stretchable temperature. As a result, improving the stretchability and the film thickness uniformity of PP were achieved by blending LMPP to PP.
      PubDate: 2017-09-17T23:46:45.225089-05:
      DOI: 10.1002/adv.21884
       
  • A study of dielectric behavior of manganese doped barium
           titanate–polyimide composites
    • Authors: Anuradha Kumari; Barnali Dasgupta Ghosh
      Abstract: In this work, a series of BaTi1−xMnxO3–polyimide films were prepared by simple solution casting method. For the preparation of composite films firstly, manganese doped barium titanate, BaTi1−xMnxO3 (where x = 0.00, 0.01, 0.03, 0.05) was synthesized by sol-gel process. The effect of Mn doping on its structural and dielectric properties was nicely explained. The highest dielectric constant value of 7,104 was obtained for BaTi0.99Mn0.01O3 (BTMn) nanoparticles with low dielectric loss value 2.44. It was observed that Mn-doping concentration on barium titanate influences its crystal structure. Improved dielectric properties were reported for nanocomposite thin films containing BaTi0.99Mn0.01O3 and polyimide (PI). A series of five homogeneous nanocomposite films were successfully prepared and were characterized thoroughly. The dielectric properties were studied as a function of frequency and loading percentage of BTMn in PI. The dielectric constant of the BTMn/PI nanocomposite films increased from 3.23 to 8.63 with the increase in loading percentage of ceramic from 0 to 5 wt%, respectively. The nanocomposite films were flexible with good mechanical properties and the flexibility decreased with increase in loading percentage of BTMn. The films showed high thermal stability in nitrogen atmosphere up to 571°C with 10% weight loss and also exhibited high glass transition temperature up to 337°C.
      PubDate: 2017-09-15T22:36:22.355759-05:
      DOI: 10.1002/adv.21886
       
  • Influence of filler loading and palm oil-based green coupling agent on
           torque rheological properties of polypropylene/cocoa pod husk composites
    • Authors: Seong Chun Koay; Ming Yeng Chan, Ming Meng Pang, Kim Yeow Tshai
      Abstract: This research examined the torque rheological properties of cocoa pod husk (CPH)-filled polypropylene (PP) composites. Composites with varying filler loading ranging from 10 to 40 phr and formulation with or without palm oil-based green coupling agent (GCA-P) were analyzed using a Brabender Plastrograph torque rheometer. The GCA-P synthesized from fatty acid of palm oil was used to enhance adhesion at the filler–matrix surface interfaces. The results reveal that PP/CPH composites containing 40 phr filler loading and GCA-P exhibited higher processing torque and power law index (n). Higher melt viscosity was recorded at higher filler loading, owning to filler agglomeration and more effective filler-matrix adhesion in the presence of GCA-P. As a result, higher energy was required to compound PP/CPH composites, which could be attributed to the increase in activation energy (Ea) at higher melt viscosity.
      PubDate: 2017-09-14T04:41:59.899858-05:
      DOI: 10.1002/adv.21883
       
  • The influence of hydrophilic mPEG segment on formation, morphology, and
           properties of PCL-mPEG microspheres
    • Authors: Yu He; Ping Liu, Chen Shi, Yongwei Liu, Songxiang Liu, Xiaobo Feng, Dehao Fu
      Abstract: This research displayed the differences of formation process, morphology, degradation, and release behaviors between PCL and PCL-mPEG microspheres. Lysozyme loaded microspheres were prepared by double emulsion evaporation method, and the double droplets transformation process was observed and compared under microscope. Microspheres morphology, in vitro degradation and release behaviors were evaluated by scanning electron microscope, gel permeation chromatography, and bicinchoninic acid protein assay kit. PCL-mPEG microspheres got a rough surface and the outer water phase penetrated into PCL-mPEG double droplet easier than PCL during the transformation, accompanied with a high broken percentage and size swelling. PCL-mPEG microspheres get a faster degradation/erosion rate than PCL microspheres, and the rate was in direct proportion to mPEG chain length. In vitro release analysis showed that PCL-mPEG microspheres get a faster release rate than PCL microspheres, and the rate was also in direct proportion to mPEG chain length.
      PubDate: 2017-09-14T02:08:25.63454-05:0
      DOI: 10.1002/adv.21887
       
  • Electrochemical co-deposition and characterization of polyaniline and
           manganese oxide nanofibrous composites for energy storage properties
    • Authors: Anwar-ul-Haq Ali Shah; Muhammad Owais Khan, Salma Bilal, Gul Rahman, Hung Van Hoang
      Abstract: Ion diffusion rate and contact surface area of conducting polymers increased by composite formation with nanometric-size materials make them promising materials in the fabrication of energy storage devices. In this work, electronically conducting polyaniline and manganese oxide (PANI/MnO2) nanofibrous composites were electrochemically co-deposited on stainless steel from binder-free electrolyte solution. Structural characterization and morphological characterization of the materials were performed with Fourier-transformed infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). SEM images show fibrous micro/nano-architecture of the composites with cluster networking structure having 200–500 nm length and 100–200 nm diameter. Electrochemical and energy storage properties of the as-synthesized materials were investigated with cyclic voltammetry (CV), galvanostatic charge discharge curves(GCDC), and potentiostatic electrochemical impedance spectroscopy (PEIS) without any binders. Electrochemical measurements as well as galvanostatic charge discharge curves at 1 mA constant current have shown maximum specific capacitance of 149 F/g for the composite prepared with 0.15 M MnSO4 in the co-deposition bath. The composites retain 67% specific capacitance even after 400 cycles, indicating the stability of synthesized composite. PEIS confirms the pseudocapacitive nature of the synthesized composites.
      PubDate: 2017-09-05T00:45:54.060941-05:
      DOI: 10.1002/adv.21881
       
  • Effects of carbon black content and size on conductive properties of
           filled high-density polyethylene composites
    • Authors: Ji-Zhao Liang; Quan-Quan Yang
      Abstract: The high-density polyethylene (HDPE) composites filled with four kinds of carbon blacks (CB) were prepared to investigate the effects of the size and content of the CB on the electrical properties of the HDPE/CB composites. It was found that the composites presented conductive percolation behavior, the CB with different size filled-systems had different percolation thresholds; the higher the structure property of the CB, the larger the particle surface area, and the smaller the particle size, the better was the conductivity, and the lower was the percolation threshold of the composites. In addition, the HDPE/CB composites showed significant positive temperature coefficient (PTC) effect and negative temperature coefficient effect. The bigger the filler particle diameter, the higher was the PTC intensity of the HDPE composite systems under the same CB weight fraction.
      PubDate: 2017-09-04T04:51:00.32273-05:0
      DOI: 10.1002/adv.21882
       
  • Preparation and characterization of starch nanocomposite embedded with
           functionalized MWCNT: Investigation of optical, morphological, thermal,
           and copper ions adsorption properties
    • Authors: Shadpour Mallakpour; Ahmadreza Nezamzadeh Ezhieh
      Abstract: The purpose of this research was to fabricate starch nanocomposites (NC)s using corn starch and MWCNTs-Valine as efficient fillers, and to examine the impact of nanofillers on the starch's properties. At first, Valine was grafted onto the MWCNTs' surfaces through a chemical reaction. Then, the functionalized MWCNTs (0.5, 1, and 2 wt.%) were embedded in the starch by ultrasonic technique. The field emission scanning electron microscopy showed homogeneous distribution of nanofillers in the starch matrix. Moreover, thermogravimetric analysis demonstrated that the starch's thermal stability was improved after addition of MWCNTs. Finally, the adsorption behavior of the prepared NC for the elimination of copper ions from the aqueous solution was investigated.
      PubDate: 2017-09-04T04:06:31.910614-05:
      DOI: 10.1002/adv.21878
       
  • Hydroxypropyl-β-cyclodextrin hybrid nanogels as nano-drug delivery
           carriers to enhance the solubility of dexibuprofen: Characterization, in
           vitro release, and acute oral toxicity studies
    • Authors: Qandeel Khalid; Mahmood Ahmad, Muhammad Usman Minhas
      Abstract: The purpose of this study was to develop and characterize hydroxypropyl-β-cyclodextrin (HPβCD) hybrid nanogels for solubility enhancement of lipophilic drug, dexibuprofen. HPβCD hybrid nanogels were designed by chemical cross-linking of hydroxypropyl-β-cyclodextrin with 2-acrylamido-2-methyl propane sulfonic acid (AMPS) via free radical polymerization. Loading efficiency, solubilization, zetasizer, FESEM Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), powder X-ray diffraction (PXRD), and in vitro drug release analysis were performed for characterization of hybrid nanogels. Efficient solubilization of dexibuprofen has been observed by HPβCD hybrid nanogels. FTIR, TGA, and DSC studies confirmed the formation of new hybrid nanogels and complexation of dexibuprofen with nanogels. XRD analysis revealed loss of dexibuprofen crystallinity in hybrid nanogels. Highly porous and amorphous nanogels showed a significant dexibuprofen release in aqueous medium. In toxicity studies, no significant changes in behavioral, physiological, biochemical, or histopathological parameters of animals endorsed that developed formulations are nontoxic and biocompatible.
      PubDate: 2017-09-04T03:55:53.704874-05:
      DOI: 10.1002/adv.21876
       
  • Improvements in mechanical strength and thermal stability of injection and
           compression molded components based on Poly Lactic Acids
    • Authors: Clizia Aversa; Massimiliano Barletta, Annamaria Gisario, Elisa Pizzi, Michela Puopolo, Silvia Vesco
      Abstract: Degradable polymers are limited by their often-insufficient mechanical and thermal properties, which limit their usage to single-use packaging items at room temperature and in dry conditions. In this respect, the present work deals with the manufacture of custom-built Poly Lactic Acids (PLAs), which are designed to be compostable, suitable for food contact and are characterized by a good compromise between mechanical properties and thermal stability. A commercial grade PLA was, therefore, compounded in a twin-screw co-rotating extruder by the use of specific additives: maleated and glycidyl methacrylate PLAs as compatibilizers/chain extenders and microlamellar talc as mineral filler/nucleation promoter. After pelletizing, the resulting compounds were melt-processed by injection and compression molding. Differential scanning calorimetry, flexural tests in static machine and top-hat cylindrical flat indentations were performed to evaluate the thermal and mechanical response of the molded components. The experimental findings show that crystallization of the PLA can be controlled by fine-tuning the compound formulation as well as by properly setting the processing parameters. In addition, achievement of the appropriate crystallization degree in the polymer can lead to molded components, which exhibit improved mechanical strength and high thermal stability.
      PubDate: 2017-08-18T00:20:47.143611-05:
      DOI: 10.1002/adv.21875
       
  • Synthesis and surface properties of a novel fluorine modified acrylate
           colloid
    • Authors: Xiuming Wang; Tingting Xu, Cuifeng Zhang, Lijun Chen
      Abstract: The novel modified acrylate colloid was synthesized by semi-continuous seeded emulsion polymerization which was initiated with potassium persulfate (KPS), and octylphenol polyoxyethylene ether (OP-10) and sodium dodecyl benzene sulfonate (SDBS) were used as surfactants. Butyl acrylate (BA) and methyl methacrylate (MMA) were used as the main monomers and hexafluorobutyl methacrylate (HFMA, C8H8F6O2), and benzyl methacrylate (BZMA, C11H12O2) were used as functional monomers. Factors such as the amount of initiator, mass ratio of SDBD to OP-10 and monomers, which have an influence on particle size and morphology of the resultant colloid, are studied. Chemical composition of the modified acrylate colloid was evaluated by Fourier transform infrared spectrometry (FTIR). The thermal performances were characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG). Furthermore, surface hydrophobicity of the latex film was examined by measurement of water absorption and water contact angle. Results indicate that the modified acrylate colloid has highest monomer conversion rate and lowest coagulation percentage when the mass fraction of emulsifier was 4% and mass ratio of SDBS to OP-10 was 1:2, mass fraction of initiator was 0.3%, mass percent of HFMA was 6%, and the amount of BZMA was 2%. Benzene ring-containing monomer is effectively participated in the reaction and has improved the thermal performance and surface properties of copolymer colloid. The resultant colloid has excellent hydrophobicity and low surface energy. Solid content of the resultant colloid was about 30% (wt %).
      PubDate: 2017-08-18T00:00:48.148969-05:
      DOI: 10.1002/adv.21874
       
  • A computer model for starve-fed single-screw extrusion of polymer blends
    • Authors: Krzysztof J. Wilczyński; Andrzej Nastaj, Krzysztof Wilczyński
      Abstract: A new computer model has been developed to simulate a starve-fed single-screw extrusion process of polymer blends. This is a composite model, which is based on combining melt conveying models with new fusion models for polymer blends. The model is able to predict pressure and temperature profiles, filling of the screw and rate of polyblend fusion. Computer calculations were executed for extrusion of high-density polyethylene and polystyrene blend at various technological conditions, and fill factor, pressure, temperature, and fusion profiles were calculated. The results of simulation studies were verified by experiment.
      PubDate: 2017-08-11T00:15:51.70099-05:0
      DOI: 10.1002/adv.21873
       
  • Analysis of structural changes in injection-molded parts due to cyclic
           loading
    • Authors: Elzbieta Bociaga; Monika Kula, Konrad Kwiatkowski
      Abstract: The investigations of the change in properties and structure of polypropylene injection-molded parts, arising from cyclic loading, are presented. The strain–stress characteristics were determined in the cyclic tensile tests, at a fixed stress or deformation level. Experiments showed that cyclic loading causes some changes in structure and mechanical properties of polypropylene samples. Smaller total strain of samples and increase in Young's modulus after each consecutive ten cycles of loading were observed as the result of loading at a fixed stress level. In experiments carried out at the fixed strain level, the width of the loop decreases with the increase in number of cycles that indicates the material strengthening. Microscopic examinations showed the change in the structure of injection-molded parts after cyclic loading. The transient zone, occurring in the area of high shear stress between the core and the skin, became significantly wider for cyclically loaded parts. Phase changes in the part structure were investigated using WAXS method. Samples exhibited the difference in the content of polypropylene polymorphic modifications between the core and skin layers. In the skin, both for nonloaded and loaded parts, the presence of β-phase was confirmed, whereas this phase did not occur in the core. The investigation by DSC method demonstrated a small change in the degree of crystallinity in the sample core after 4,000 cycles of loading, while in the skin layer, the degree of crystallinity was reduced by about 2% when compared to the value obtained for samples after one loading cycle.
      PubDate: 2017-07-31T07:21:33.375237-05:
      DOI: 10.1002/adv.21872
       
  • Modeling and optimization of electrospinning of polyvinyl alcohol (PVA)
    • Authors: Mohamed Elkasaby; Hussien A. Hegab, Atef Mohany, Ghaus M. Rizvi
      Abstract: The electrospun fibers can have applications in diverse fields, such as tissue scaffolds, optical electronics, nanocatalysis, and sound absorption. Nanoscale fibers with a higher surface area can provide superior mechanical, physical, and thermal properties. Therefore, investigation of the factors affecting the electrospinning process, for various materials, is required. In this study, the design of experiments issued for optimization of electrospinning of polyvinyl alcohol (PVA). Analysis of variance (ANOVA) and the Taguchi orthogonal array L27OA are employed to analyze the influence of process control parameters. The variables studied are the applied voltages, solution concentrations, rotational speeds, collecting distances, and flow rates. A mathematical model of the polymer fiber diameter as a function of significant process parameters has been built using response surface methodology (RSM). The concentration percentage and the flow rate were determined to be the most significant process variables at 99% and 90% confidence levels, respectively. The predictive model provides 84.34% average model accuracy, which is considered acceptable as this study deals only with 27 of 243 trials needed for a full study based on principles of design of experiments. An additional ANOVA test and corresponding mathematical model have been developed to obtain the interaction effects for processing parameters.
      PubDate: 2017-07-24T01:11:01.967078-05:
      DOI: 10.1002/adv.21869
       
  • In situ preparation of chitosan/gold nanocomposite: Structural and
           catalytic properties
    • Authors: Wael H. Eisa; Tarob Abdelnaby, Shahenda Mostafa, Mohamed Y. Elzayat
      Abstract: Chitosan-stabilized gold nanoparticles (Cs/Au) film was prepared by casting strategy without a need for reducing and/or stabilizing agents. The shape, size, and crystalline phase were studied using UV-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction (XRD). The nature of the interaction between the Cs and Au nanoparticles was studied using the Fourier transformer infrared (FTIR) spectroscopy. The as-prepared Cs/Au nanocomposite film showed high activity in the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of an excess amount of NaBH4. Furthermore, the Cs/Au film is easily separable, as well as remains active after reused for 3 times. The Cs/Au nanocomposite film could be a promising candidate for various catalytic reactions.
      PubDate: 2017-07-24T01:06:31.935048-05:
      DOI: 10.1002/adv.21867
       
  • pH stimuli-responsive poly(acrylamide-co-sodium alginate) hydrogels
           prepared by γ-radiation for improved compressive strength of concrete
    • Authors: Mohamed Mohamady Ghobashy; Ghada Bassioni
      Abstract: Cross-linking of superabsorbent hydrogels based on poly(acrylamide-co-sodium alginate) is carried out using 60Co γ-radiation. Hydrogels of PAM/NaAlg with 1.5:0.5 and 1.0:1.0 w/v concentrations showed good gel contents of 87 and 66 (%) and swelling degrees in water of 3.7 and 5 (g/g) after 40 min, respectively. The chemical structure of the hydrogel is confirmed by FTIR, XRD, and ESR. The morphology of the hydrogel is observed using scanning electron microscopy. Intramolecular H-bonding in the hydrogel network is confirmed by TGA and DSC. The pH-responsive swelling behavior of (PAM-co-NaAlg) hydrogels is tested in different pH ranges showing higher swelling capacities in basic than in acidic media. This property proposes the use of (PAM-co-NaAlg) hydrogel as internal curing agent for concrete. The hydrogel is examined with cement weight ratios of (0.1–0.5) wt%. The study shows that cement with (PAM-co-NaAlg) hydrogel improves the compressive strength of cement at 0.1 and 0.2 wt%.
      PubDate: 2017-07-20T00:26:37.158011-05:
      DOI: 10.1002/adv.21870
       
  • Effectiveness of different kinds of antioxidants in resin-cured bromobutyl
           rubber vulcanizates
    • Authors: Na Lu; Mei Shen, Zhanfeng Hou, Prakashan K, Zhenxiang Xin
      Abstract: Antioxidants are customarily used in elastomer compounds to enhance the service life of vulcanizates enduring high temperatures, but proper selection and dosage of the antioxidant is critical to obtain maximum beneficial effect. In this study, the effectiveness of several commercially available antioxidants on the performance of a resin-cured bromobutyl rubber (BIIR) vulcanizate was investigated. The antioxidants investigated belonged to different chemical classes such as p-phenylene diamine (antioxidant 4010NA), secondary amine (antioxidant 445), quinoline (antioxidant RD), and phenolic (antioxidants BHT, 1010, and 2246). The physicomechanical properties of the BIIR vulcanizates containing the various antioxidants were tested at room temperature, at higher temperatures, after subjecting to heat aging, and after storage. The results show that the physicomechanical properties of the BIIR vulcanizate severely deteriorate when antioxidant 4010NA is used. Among the other antioxidants used, the phenolic-type antioxidant BHT is found to be better for the resin-cured BIIR vulcanizate of this study.
      PubDate: 2017-07-18T22:45:30.183165-05:
      DOI: 10.1002/adv.21865
       
  • Theoretical analysis of the spunbond process and its applications for
           polypropylenes
    • Authors: Toshitaka Kanai; Youhei Kohri, Tomoaki Takebe
      Abstract: The theoretical analysis of the spunbond process was set up and applied to polypropylene (PP) and its blends. The effect of blending low tacticity polypropylene (LMPP) to high tacticity PP on the spinnability of the spunbond process was investigated. A small amount of LMPP was found to stabilize the high-speed spinning of PP, and very fine fibers were obtained. From the calculated results, it was speculated that the improvement of spinnability originated from the suppression of crystallization speed and strain rate in the spinning process. The physical properties of the spunbond nonwoven fabrics were also investigated.
      PubDate: 2017-07-17T00:40:56.020405-05:
      DOI: 10.1002/adv.21866
       
  • Processability and mechanical properties of bioplastics produced from
           decoloured bloodmeal
    • Authors: Casparus Johannes Reinhard Verbeek; Aaron Low, Mark Christopher Lay, Talia Maree Hicks
      Abstract: Bloodmeal is a protein-rich coproduct of the meat industry and can be converted into a thermoplastic. A solution of peracetic acid can be used to degrade colored compounds in bloodmeal, yielding a light yellow material. This causes an increase in β-sheets in the protein's secondary structure, but the addition of sodium dodecyl sulfate (SDS) and triethylene glycol (TEG) reduced α-helical and β-sheet content, thereby increasing random coils. Without SDS, chains were less capable of folding into these structures, preventing sufficient intermolecular interactions and chain entanglement, leading to low specific mechanical energy input (SME) during extrusion, and poor consolidation. The whiteness of molded samples showed no correlation with SME during extrusion or the degree of consolidation after extrusion; however, they were observed to have a higher level of whiteness with increasing TEG content and should be considered as a secondary process not directly linked to extrusion. Increasing the amount of water during extrusion increased the Young's modulus (E) by facilitating formation of new interactions, while increasing TEG decreased E as a result of plasticization. The action of SDS on destabilizing electrostatic and hydrophobic interactions was beneficial to extrusion, although it had no further effect during injection molding. TEG had virtually no effect on tensile strength, although it was required for flow and facilitated the formation of strong interactions after water had been evaporated during conditioning.
      PubDate: 2017-07-16T23:00:38.071287-05:
      DOI: 10.1002/adv.21868
       
  • Biosourced blends based on poly (lactic acid) and polyamide 11:
           Structure–properties relationships and enhancement of film blowing
           processability
    • Authors: Fatma Walha; Khalid Lamnawar, Abderrahim Maazouz, Mohamed Jaziri
      Abstract: The purpose of the present work is to develop a new biomaterial with suitable melt strength, stiffness-to-toughness balance, and the required thermal performance for food packaging applications. The study is dedicated to investigating a new physical compatibilization approach of biosourced materials as well poly (lactic acid) (PLA) and polyamide 11 (PA11) in comparison with the chemical compatibilization through addition of a multifunctionalized epoxide. For this reason, this paper deals with gaining better understanding physical compatibilization in the biosourced blend with the incorporation of an acrylic melt strength enhancer into PLA/PA11 blend. The main focus of this paper is studying how physical compatibilization improves melt strength in comparison with chemical approach. Hitherto, the chain extension–branching balance was demonstrated to be difficult to be controlled and decoupled from chemical compatibilization at the polymer–polymer interface. Hence, the physical approach is presented as an original route in this work to develop a PLA-based blend with good film blown processability and engineering properties. Morphological, rheological and thermomechanical properties of the new obtained biosourced blends were studied. The physical compatibilization effect was confirmed by the tuning interfacial properties. The extensional rheology highlighted that melt strength for the physical blends was also improved without any pronounced strain hardening in comparison with reactive blends. Besides, a great enhancement of the blowing processing windows of physically PLA-PA11 compatibilized blend was highlighted while higher blow-up ratio and take-up ratio values were obtained. Overall, a correlation between the obtained thermal and crystalline properties was performed for the optimal biosourced blown film.
      PubDate: 2017-07-12T23:30:45.0946-05:00
      DOI: 10.1002/adv.21864
       
  • Mechanical recycling simulation of polylactide using a chain extender
    • Authors: Marina Fernandes Cosate de Andrade; Gustavo Fonseca, Ana Rita Morales, Lucia Helena Innocentini Mei
      Abstract: This work studied the commercial chain extender effectiveness on the mechanical recycling simulation of a pristine PLA using a single-screw extruder. We processed the material by two extrusion cycles to simulate a recycling process. In the second extrusion, part of the material was processed with chain extender and we evaluated its molecular weight, thermal degradation, melt flow index (MFI), thermal transitions, and mechanical properties. The molecular weight for the extruded neat PLA decreased and the MFI and crystallinity degree increased while the mechanical properties worsened. The onset thermal degradation occurred at lower temperature for the processed material. With the introduction of the chain extender, there was a recovery of properties with the increase in the polymer molecular weight, decrease in the MFI and crystallinity degree, and an improvement in both thermal stability and mechanical properties in relation to recycled PLA without this component.
      PubDate: 2017-07-12T03:45:38.149453-05:
      DOI: 10.1002/adv.21863
       
  • Application of tree biochar in PDMS pervaporation membranes
    • Authors: Yongqiang Lan; Weihong Wang
      Abstract: In this study, three kinds of biomass materials (lodgepole pine bark, larch wood, larch bark) were used to prepare biochar (BB), and the prepared products as fillers were mixed with polydimethylsiloxane (PDMS) for preparing composite membranes which were used for separating ethanol from water by pervaporation (PV). In accordance with the experiment results, the lodgepole pine bark BB was the best filler for the selective membrane to ethanol. The silane coupling agents NH2(CH2)3Si(OC2H5)3 (KH-550) and CH2=CH-Si(OCH3)3 (YDH-171) were applied in the modification of lodgepole pine bark BB. And the separation performances of the BB/PDMS composite membranes were researched in detail. The results showed that the permeability (flux and separation factor) of composite membranes has been significantly improved with the addition of modified BB. YDH-171 was more effective than KH-550. The optimum PV performances (the separation factor 11.3 and the corresponding flux 227.25 g m−2 h−1) were obtained by adding 3 wt. % modified BB for a 10 wt. % and 40°C ethanol solution. This study indicated the potential application of BB nanoparticles in preparing pervaporation separation membrane.
      PubDate: 2017-07-10T01:22:52.591814-05:
      DOI: 10.1002/adv.21856
       
  • Chitosan phthalate: A novel polymer for the multiparticulate drug delivery
           system for diclofenac sodium
    • Authors: Dasari Subramaniyam Karuna; Grace Rathnam, Udhumansha Ubaidulla, Mani Ganesh, Hyun Tae Jang
      Abstract: This study investigates the preparation of colon specific drug delivery of diclofenac sodium (DS) using maltiparticulate system with chitosan phthalate (CP). Technique adopted to prepare sphere shaped multiparticulate system was extrusion and spheronization. The prepared pellets resulted with good spherical geometry with 1.1 ± 0.20 mm diameter. DS loaded system shows a maximum delivery pH of 7.4 and the same depressed at pH 1.2. The developed system significantly (p 
      PubDate: 2017-07-08T02:35:34.66718-05:0
      DOI: 10.1002/adv.21859
       
  • Synthesis, optimization, and characterization of poly
           (Styrene-co-Acrylonitrile) copolymer prepared via precipitation
           polymerization
    • Authors: Mohamed R. El-Aassar; Mamdouh S. Masoud, Marwa F. Elkady, Ahmed A. Elzain
      Abstract: Poly (Styrene-co-Acrylonitrile) (poly (St-co-AN) copolymer nanoparticles with controllable size are synthesized by a simple and cheap precipitation polymerization technique of styrene (St) and acrylonitrile (AN) monomers in aqueous medium using potassium persulfate (KPS) redox initiation system. Preparation of poly (St-co-AN) and studying all the parameters affecting the polymerization process such as time, temperature, monomer ratio, initiator molarity, cosolvent ratio, and solvent were considered. The resultant poly (St-co-AN) was compared with other studies which used different comonomers with AN, the comparison was assessed by evaluating the polymer conversion yield side. Maximum polymerization conversion yield, 66.5%, was obtained with St:AN (30%:70%) comonomer ratio. The smallest particle size obtained with this method was close to 16.17 nm and controlled by variation in polymerization conditions. The structure of poly (St-co-AN) copolymers were confirmed by Fourier transform infrared (FTIR), thermo gravimetric analysis (TGA), and differential thermal analyzer (DTA). The morphological structure of the copolymer particles was indicated by scanning electron microscope (SEM) photographs. The polymeric particle size was studied using particle size analyzer.
      PubDate: 2017-07-03T23:30:54.366179-05:
      DOI: 10.1002/adv.21860
       
  • Influence of silane-modified Vinyl ester on the properties of Abaca fiber
           reinforced composites
    • Authors: Syed Nabeel Ahmed; M.N. Prabhakar, Siddaramaiah, Jung-IL Song
      Abstract: The versatility of the fiber reinforced composites has significantly replaced some of the sophisticated metal components in certain sectors of industries. The matrix could be altered to improve self-properties via silane modifiers by forming chemical linkages with the matrix in harmony with the reinforcing agents. This research work is an endeavor to enhance the traits of Vinyl ester by scrutinizing the influence of silane chemical agents using Hexamethyldisiloxane (HMDS). The dispersion time and concentration of these chemicals in matrix were optimized and henceforth a natural reinforcement, Abaca fabric was incorporated to constitute Natural fiber composite via Vacuum Assisted Resin Transfer Molding (VARTM) technique. The effect of resin modification on mechanical, thermal, and physical properties of Vinyl ester/Abaca (VE/AF) composite was examined. HMDS resin modified composite showed an improvement in the mechanical and flame retardant properties when compared to the pristine composite due to the formation of siloxane bonding which is compatible with the functional groups of both the matrix and the fabric. FT-IR and FESEM characterizations have showed imperative evidences to support the results. This investigation provides a channel for enhancing the properties of natural fiber composites via chemical modification technique.
      PubDate: 2017-07-03T03:21:46.995383-05:
      DOI: 10.1002/adv.21855
       
  • Characterization, thermal behavior, and electrical measurements of
           poly[4-(2-bromoisobutyroyl methyl)styrene]
    • Authors: Fatih Biryan; Kadir Demirelli
      Abstract: The 4-(2-bromoisobutyroyl methyl)styrene [BBMS] monomer was synthesized. The homopolymer of BBMS was prepared by free radical polymerization method. The decomposition behavior of P(BBMS) was thermally investigated by thermogravimetric analysis (TGA). For thermal decomposition kinetics of poly(BBMS), Flynn–Wall–Ozawa method was applied to thermogravimetry curves. The first step, which is one of the two decomposition stages, is comprehensively related to elimination of hydrogen bromide and the other step is related to a multi-step process. The activation energy (Ea) of thermal decomposition of the first step and 50% weight loss is 148.5 and 190.7 kJ/mol, respectively. The results showed that the side group elimination without chain breaking comprehensively proceeded at lower temperature, and at progressive temperatures subsequently the specific chain scission did so. Degradation of poly(BBMS) did not lead to depolymerization. 1H, 13C-NMR, and FT-IR analyses showed that the decomposition products during degradation of poly(BBMS) to 260°C were comprehensively HBr and methacrylic acid. Electrically conducting graphene-based poly(BBMS) composites were prepared. The DC and AC electrical measurements of graphene-based poly(BBMS) composites were carried out. The AC dielectric measurements of poly(BBMS) were investigated up to 70°C between 100 Hz and 20 kHz depending on the alternating current conductivities. The dipolar functional groups (C–O, C=O, and Br) of the BBMS segment possesses significantly affect the dielectric constant. Also, the activation energy profile of different graphene/poly(BBMS) composites were revealed by measuring DC conductivity of individual composite material.
      PubDate: 2017-07-03T02:55:58.349377-05:
      DOI: 10.1002/adv.21858
       
  • Gas permeation properties of cellulose acetate/silica nanocomposite
           membrane
    • Authors: Mohaddeseh Najafi; Morteza Sadeghi, Ali Bolverdi, Mahdi Pourafshari Chenar, Majid Pakizeh
      Abstract: In this study, the effects of silica nanoparticles on the permeability of pure CO2, O2, and N2 gases in cellulose acetate (CA) membrane have been studied. Silica particles were prepared via the sol–gel method through the hydrolysis of tetraethyl orthosilicate (TEOS). CA and CA/silica nanocomposite membranes were prepared by thermal phase inversion method. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transfer infrared (FTIR) analyses were employed to characterize the CA and CA/silica nanocomposite membranes. Gas permeation experiments showed an increase in the permeability of CO2 from 6.32 to 7.3 barrer and a reduction in the permeability of N2 from 0.18 to 0.09 barrer with the increment in silica content of the prepared composite membranes up to 20 wt%. Therefore, CO2/N2 selectivity of the nanocomposite membranes increased by increasing the silica content in the polymer matrix from 30 to 80 for 20 wt% load of silica.
      PubDate: 2017-06-29T06:45:49.350803-05:
      DOI: 10.1002/adv.21862
       
  • Protein adsorption and cell behaviors on polycaprolactone film: The effect
           of surface topography
    • Authors: Thitikan Khampieng; Vipawee Yamassatien, Pongpol Ekabutr, Prasit Pavasant, Pitt Supaphol
      Abstract: Protein adsorption is the first phenomenon that occurs when foreign materials are inserted into the body. Materials used in biomedical applications can have different surface topologies. Knowledge of the effect of the surface on protein adsorption is important due to its influence on cell behavior. The main objective of this study was to analyze polycaprolactone (PCL) films with different surface topologies. Protein adsorption was studied using bovine serum albumin (BSA) as the biomolecule. Different surface topologies of PCL were induced by phase separation using solvents with various solubility parameters. The investigated solvents were chloroform, acetone, tetrahydrofuran (THF), and ethanol (EtOH). The PCL films with different surface topologies and protein-adsorbed PCL films were studied with respect to their hydrophobicity, the concentration and nature of functional groups on their surface, their surface roughness, and their cytotoxicity. Atomic force microscopy revealed that the films with the roughest surface were cast from 40:60 EtOH:THF and contained significantly larger amounts of adsorbed protein. Proteins preferentially adsorbed onto rough surfaces. The cell culture also indicated that mouse-calvaria-derived pre-osteoblastic cells proliferated best and exhibited the greatest amount of calcium deposition on the surface with the largest amount of adsorbed protein.
      PubDate: 2017-06-27T23:16:33.662345-05:
      DOI: 10.1002/adv.21861
       
  • Bioactive nanofibrous structures based on hyaluronic acid
    • Authors: Ewelina Pabjańczyk-Wlazło; Paulina Król, Izabella Krucińska, Michał Chrzanowski, Michał Puchalski, Grzegorz Szparaga, Sławomir Kadłubowski, Maciej Boguń
      Abstract: Studies related to selection of molar mass of hyaluronic acid and analysis of rheological properties of hyaluronic acid solutions modified with bioactive substances, used in spinning, were undertaken within the presented work. A cephalosporin group antibiotic, Biofuroxime®, was used, together with the nanoadditives zinc oxide (ZnO) and hydroxyapatite (HAp). Electrospinning studies were performed on selected solutions using a large scale laboratory station, allowing the process to be performed using three nozzles supplying the spinning solution. Optimum electrospinning conditions were selected on the basis of the performed study, which allow fibrous structures made of elementary fibres with diameters below 200 nm to be obtained. Studies showed that the most preferred distance between the nozzle and the collecting manifold was 450 mm and the most preferred applied voltage was 30 kV. The obtained, modified nanofibres of hyaluronic acid comprise structures for use in the production of biomaterials with a wide range of applications in tissue engineering.
      PubDate: 2017-06-25T23:24:32.751102-05:
      DOI: 10.1002/adv.21851
       
  • A priority supposition for estimation of time-dependent changes in
           thickness and weight of polymeric flat sheet membranes fabricated by the
           nonsolvent induced phase separation (NIPS) technique
    • Authors: Milad Asgarpour Khansary; Mohammad Ali Aroon, Azam Marjani, Saeed Shirazian
      Abstract: During the fabrication procedure of polymeric membranes using nonsolvent induced phase inversion technique, thickness and weight of the polymeric cast film change rapidly. The only available guideline just presents a qualitative criterion for thickness change in which “penetration of the denser species into the film and the elimination of the lighter ones from film to coagulation bath” have been related to the densification of the cast solution and its thickness reduction. While it is well-suited for cellulose acetate/acetone/water ternary system, it is not applicable to our investigated systems, that is, polyethersulfone/n-methyl-pyrolidine/water and polysulfone/N-methylpyrrolidone/water. Thus, here the thermo-kinetic behavior of NIPS process was discussed, and then a thermodynamic model was developed, in which only initial cast film and final membrane properties were used as inputs. Two new simple suppositions were derived and examined. The use of thermodynamic modeling approach results in desirable estimation of overall changes, and the proposed suppositions also can be reliably used for prediction of changes in mass and thickness experienced by cast film NIPS process. It was shown that without the implication of some serious assumptions, it is impossible to derive the old supposition from theoretical concepts. It was also found that the interpretation of film thickness reduction in literatures cannot be validated. Using the presented theoretical concept, one can obtain an overview of the decrease and/or increase in thickness and/or weight of final fabricated membrane prior to any experimental investigation.
      PubDate: 2017-06-22T23:30:37.044209-05:
      DOI: 10.1002/adv.21854
       
  • The self-healing cross-linked polyurethane by Diels–Alder
           polymerization
    • Authors: Yanyan Wei; Xiaoyue Ma
      Abstract: Polymer materials containing Diels–Alder (abbreviated DA) groups show good self-healing ability under certain conditions. In this study, the thermal reversible DA bond was introduced into polyurethane by the design of molecular chain to obtain the self-healing properties. The pre-polyurethane (HTK) end-capped with furan rings was synthesized by hexamethylene diisocyanate trimer and furfuryl alcohol firstly. Then, HTK was mixed with bismaleimide (BMI) to synthesize the cross-linked polyurethane HTK-PU. Finally, the properties of the HTK-PU were characterized. It can be observed from DSC that the DA reaction occurred at 76°C and the r-DA reaction occurred at 109.5°C. This cross-linked polyurethane shows a remarkable high hardness (shore D80). When preserved at 80°C for 6 hr, the self-healing efficiency of the HTK-PU was 53.75% known from tensile test, and cracks on it virtually disappeared as observed from polarizing microscope (POM). When preserved at 80°C for 12 hr, the self-healing efficiency was 67.56%.
      PubDate: 2017-06-19T00:11:00.867634-05:
      DOI: 10.1002/adv.21857
       
  • Development and characterisation of functionalised AL-MCM-41 reinforced
           caprolactam toughened DGEBA epoxy-cyanate ester polymer nanocomposites
    • Authors: Muthu Rajamani Jayasree; Srinivasan Anandakumar, Muthukaruppan Alagar
      Abstract: The present work aims at the toughening of DGEBA epoxy-cyanate ester hybrid with caprolactam and its subsequent reinforcement with different weight percentages of (1, 3, 5, and 7 wt%) 3-glycidylpropoxytrimethoxysilane functionalized Al-MCM-41 (F-Al-MCM-41) to fabricate F-Al-MCM-41 reinforced caprolactam toughened DGEBA epoxy-cyanate ester polymer nanocomposites. 1H NMR and 13C NMR data confirmed the formation of epoxy cyanate ester. Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) results ascertained the curing behaviour of polymer composites. Data from thermal and dielectric studies reveal that 7 wt% F-Al-MCM-41 reinforced caprolactam toughened DGEBA epoxy-cyanate ester exhibits superior thermal stability and dielectric constant than that of a neat composite. The SEM- EDAX analysis investigated the surface morphology of polymer composites. Data obtained from DMA showed that 7 wt% polymer nanocomposite possesses the highest storage modulus among the samples.
      PubDate: 2017-06-14T23:43:29.292214-05:
      DOI: 10.1002/adv.21849
       
  • Mechanical, thermal and accelerated weathering studies of bio-based
           polyurethane/clay nanocomposites coatings
    • Authors: Hemjyoti Kalita; Rashmirekha Kamila, Smita Mohanty, Sanjay Kumar Nayak
      Abstract: Biobased polymer has taken tremendous attention in recent times. In the present study bio-based polyurethane have been synthesized from the vegetable oil i.e., dehydrated castor oil, 1,4-butanediol and isophorone diisocyanate in presence of a catalyst by solution polymerization method. Then polyurethane nanocomposites were synthesized using different amount of nanoclay (C30B) (1, 3 and 5 wt%). The synthesis of polyurethane and its nanocomposites were confirmed by FTIR and XRD analysis. The mechanical properties such as tensile strength (2.2–4.5 MPa), elongation at break (299%–435%) hardness (46–70) and abrasion resistance (351–201 mg/1,000 cycles) increased with the increase of nanoclay content. The initial thermal degradation temperature found to increase from (220 to 290°C) with the increase of nanoclay content in the nanocomposites. The nanoclay was interacted with the hard segment of the matrix polymer as reflected from the atomic force microscopy studies. Weathering study revealed that nanocomposites have higher weather resistance capacity than pristine polyurethane. It can be concluded that the prepared nanocomposites might be good outdoor topcoat materials.
      PubDate: 2017-06-11T23:30:38.946649-05:
      DOI: 10.1002/adv.21853
       
  • In vitro and ex vivo assessment of hydrophilic polymer- and
           plasticizer-based thin buccal films designed by using central composite
           rotatable design for the delivery of meloxicam
    • Authors: Muhammad Zaman; Muhammad Hanif
      Abstract: The purpose of the study was to design a dosage form with ability to deliver drug immediately, hence providing rapid relief in certain pain ailments. Meloxicam (MLX) was selected as a model drug and buccal films were designed by using the solvent casting technique. A central composite rotatable design (CCRD) was used as a statistical tool to design and optimize the film formulations. No noticeable interaction was found between the drug and polymer when they were subjected to Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed the smooth surface of the film and uniform mixing of drug and polymer. X-ray diffractometry (XRD) was carried out to observe crystalline and amorphous nature of meloxicam. Differential scanning calorimetric (DSC) analysis was used to investigate the thermal behavior of free drug and drug-loaded formulation. The prepared film showed good mechanical property as folding endurance was found to be greater than 100 in all formulations. The cumulative drug release was found to be more than 80% in initial at dissolution time of 5 min, when the prepared films were subjected to dissolution studies in phosphate buffer at pH 6.8. Thus, it can be concluded that the hydrophilic polymer and plasticizer have definite impact on formulation and characteristics of rapidly dissolving buccal films and have the ability to prepare a suitable immediate release buccal film of meloxicam.
      PubDate: 2017-06-09T23:20:30.78906-05:0
      DOI: 10.1002/adv.21841
       
  • Preparation of magnetic nanoparticles functionalized with poly
           (styrene-2-acrylamido-2-methyl propanesulfonic acid) as novel adsorbents
           for removal of pharmaceuticals from aqueous solutions
    • Authors: Mozhgan Hayasi; Naghi Saadatjoo
      Abstract: This work describes the removal of three pharmaceuticals, namely ceftriaxone sodium (CFX), diclofenac sodium (DCF) and atenolol (ATN) from water using magnetic poly (styrene-2-acrylamido-2-methyl propanesulfonic acid) (St-AMPS) adsorbent. This adsorbent was characterized by several techniques such as FTIR, TEM, TGA, VSM and DLS. Three kinetic models, pseudo-first-order, pseudo-second-order and intra-particle diffusion models were used to study the adsorption kinetics. The results showed that the adsorption kinetics of pharmaceuticals onto magnetic poly (St-AMPS) adsorbent followed the pseudo-second-order model and were relatively rapid. In addition, it was found that the intra-particle diffusion was not the sole rate-controlling step and the adsorption of pharmaceuticals onto adsorbent occurred via two steps adsorption process. The experimental data were fitted with three isotherm models including Freundlich, Langmuir and Dubinin-Radushkevich (D-R). It was found that the adsorption of pharmaceuticals onto magnetic poly (St-AMPS) nanoparticles was the best described by the Langmuir model. Maximum adsorption capacities of 150.602, 47.824 and 119.904 mg/g were obtained for DCF, ATN and CFX, respectively. Also the obtained free energy from D-R isotherm (6.19, 4.93 and 6.45 kJ/mol for DCF, ATN and CFX respectively) indicated that the adsorption process was a physiosorption. Magnetic poly (St-AMPS) adsorbent could be recycled for removal of CFX, DCF and ATN by alkaline aqueous solution (pH 8). Therefore, this adsorbent can act as a promising adsorbent for water treatment processes.
      PubDate: 2017-06-08T23:40:35.414366-05:
      DOI: 10.1002/adv.21852
       
  • Production of cationic dyeable poly(ethylene terephthalate) fibers via
           nanotechnology
    • Authors: Mohammad Ali Tavanaie; Roya Dastjerdi, Nazanin Sepehrian, Alireza Ghasami
      Abstract: Nano-titanium oxide/nano-zinc oxide/poly(ethylene terephthalate) (nano-TiO2/nano-ZnO/PET) nanocomposite fibers were successfully prepared by a laboratory-scale melt spinning process. The properties of pure and modified PET fibers including tensile (tenacity and elongation at break) and thermal properties, and the dyeability properties of cationic dyes with and without carrier were studied. The modified PET nanocomposite fiber containing 0.15 wt% nano-titanium dioxide and 0.15 wt% nano-zinc oxide showed the best cationic dye adsorption property, excellent washing fastness and good light fastness. Also, a significant effect on the dye adsorption of modified PET fibers was observed at boiling temperature due to the presence of carrier agent.
      PubDate: 2017-06-08T02:05:36.709023-05:
      DOI: 10.1002/adv.21848
       
  • The relationship between morphology development and mechanical properties
           in thermoplastic protein blends
    • Authors: Matthew J. Smith; Casparus J. R. Verbeek
      Abstract: Novatein thermoplastic protein was blended with modified polyethylene (containing either epoxy, carboxylic acid functionalities partially neutralised to produce zinc carboxylate salts, or maleic anhydride functionalities) to alter blend morphology and to manipulate thermal and mechanical properties. Up to 40 pphNovatein polyethylene (PE) was blended with Novatein by extrusion and injection moulding. Using zinc ionomer resulted in optimal properties and was compatible with a finely dispersed morphology at high content; high interfacial tension (σ) and a viscosity ratio (λ) of ~1 was observed. Unmodified blends and those containing epoxy functionalities showed co-continuity at low PE content. Whilst co-continuity appeared to increase impact resistance, other mechanical properties decreased due to lack of phase interaction. Maleic anhydride-grafted-polyethylene blends showed a finely dispersed PE phase, yet was less compatible. Zinc ionomer was deemed to be the most appropriate for modification of mechanical properties in Novatein.
      PubDate: 2017-06-07T23:25:59.509903-05:
      DOI: 10.1002/adv.21847
       
  • Effect of strain-induced crystallization on the tear strength of natural
           rubber/styrene butadiene rubber blend
    • Authors: Fumitoshi Noguchi; Yuanbing Zhou, Kenichiro Kosugi, Yoshimasa Yamamoto, Phan Trung Nghia, Masao Fukuda, Seiichi Kawahara
      Abstract: Strain-induced crystallization of natural rubber (NR) can greatly influence the mechanical properties of NR blends. In this study, we investigated the effect of strain-induced crystallization on the tear energy (G) of NR/styrene butadiene rubber (SBR) blends with different compositions and cross-link densities. Using a shift factor, we could superimpose G of an SBR blend and an NR/SBR (1/9) blend onto a single master curve. In contrast, G of NR was split into two master curves. Although the master curve of G for the NR/SBR (3:7) blend was split, increasing the cross-link density threefold made it possible to superimpose it onto a single master curve. Strain-induced crystallization of NR in the NR/SBR blend did not occur as a result of decreasing the NR content, increasing the cross-link density, or removing fatty acids. Together, these findings indicate that strain-induced crystallization of NR plays an important role in the mechanical properties of the blend.
      PubDate: 2017-06-06T05:50:31.011419-05:
      DOI: 10.1002/adv.21843
       
  • The influence of nano-silica on properties of sulfonated
           polystyrene-lignosulfonate membranes as proton exchange membranes for
           direct methanol fuel cell application
    • Authors: Siang Tandi Gonggo; Bunbun Bundjali, Ketut Hariyawati, I Made Arcana
      Abstract: The membranes of sulfonated polystyrene, lignosulfonate and nano-silica (SPS-LS-SiO2) that contain different percentages of nano-silica (1%–5% [w/w]) were prepared and characterized for polymer electrolyte membrane fuel cell (PEMFC). Nano-silica is an inorganic compound with a surface area of 200 m2/g, and it has a hygroscopic property so that the presence of nano-silica in membrane can increase properties of membrane. The SPS-LS-SO2 membranes were prepared by casting polymer solution and membranes were characterized by functional groups analysis, water uptake, ion exchange capacity (IEC), proton conductivity, methanol permeability, thermal stability, mechanical properties, and surface morphology. The results show the increase of nano-silica composition in SPS-LS-SiO2 membranes, the IEC, water uptake, proton conductivity increase, but a pore size of membrane decreases. On the other hand, it can maintain the mechanical strength of membranes. The SPS-LS-SiO2 membranes with nano-silica composition of 2%–5% (w/w) have the same properties with Nafion®117, especially in proton conductivity at the same treatment and measurement conditions, and its methanol permeability is about 28%–35% smaller than that of Nafion®117 (2.09 × 10−6 cm2/s), so this SPS-LS-SiO2 membrane could be used as a polymer electrolyte membrane for direct methanol fuel cell (DMFC) application.
      PubDate: 2017-06-05T04:50:20.04672-05:0
      DOI: 10.1002/adv.21844
       
  • Effects of mixing di- and tri-functional epoxy monomers on
           epoxy/thermoplastic blends
    • Authors: Gianluca Cicala; Salvatore Mannino, Alberta Latteri, Giulia Ognibene, Giuseppe Saccullo
      Abstract: Two different epoxy monomers, based on the diglycidylether of bisphenol A (DGEBA) and triglycidyl-p-aminophenol (TGAP), which are di- and tri-functional, respectively, were mixed in varying proportions and cured with bis(2,6-diethylaniline) (MDEA). Toughened epoxy resins were prepared by adding a coPolyethersulfone (coPES) to the resin mixture. The dynamic mechanical and morphological properties of the cured materials were measured. It was found that the blends based on TGAP presented different viscoelastic and morphological behavior compared to DGEBA-based formulations. Mixing TGAP with DGEBA resulted in increased glass transition temperature and homogeneous phase morphology distribution.
      PubDate: 2017-06-02T04:26:01.533355-05:
      DOI: 10.1002/adv.21845
       
  • Electrospinning and crosslinking of polyvinyl alcohol/chitosan composite
           nanofiber for transdermal drug delivery
    • Authors: Zhixiang Cui; Zifeng Zheng, Luyin Lin, Junhui Si, Qianting Wang, Xiangfang Peng, Wenzhe Chen
      Abstract: The drug-loaded polyvinyl alcohol (PVA)/chitosan (CS) composite nanofibers intended to be used as matrix for transdermal drug delivery were fabricated by electrospinning, and then crosslinked through glulataraldehyde (GA). The morphology, chemical structure, thermal behavior, mechanical properties, hydrophilicity and drug release properties of drug-loaded PVA/CS composite nanofibers before and after crosslinking were characterized. The results showed that the morphology of PVA/CS composite nanofibers was not been destroyed in both crosslinking and in vitro drug release process. The Young's modulus, tensile strength, thermal properties and hydrophobicity of crosslinked PVA/CS composite nanofibers significantly increased in comparison with those of PVA/CS (without crosslinking) due to the formation of crosslinking network structure. In vitro release studies showed that crosslinked PVA/CS composite nanofibers had lower drug release rate and smaller amount of drug burst release than that of PVA/CS. According to release exponent “n”, the release of ampicillin sodium from crosslinked PVA/CS composite nanofibers fit to the Fickian diffusion mechanism. Those results demonstrate the potential utilization of crosslinked PVA/CS composite nanofibers as a transdermal drug delivery system.
      PubDate: 2017-06-02T01:05:49.115859-05:
      DOI: 10.1002/adv.21850
       
  • Improved sand erosion resistance and mechanical properties of
           multifunctional carbon nanofiber nanopaper-enhanced fiber reinforced epoxy
           composites
    • Authors: Dan Zhang; Eusebio Cabrera, Yanan Zhao, Ziwei Zhao, Jose M. Castro, Ly J. Lee
      Abstract: Multifunctional carbon nanofiber (CNF) nanopaper-enhanced glass fiber reinforced epoxy polymer composites (GFRPC) with improved sand erosion resistance, mechanical properties, and electromagnetic interference (EMI) shielding have been fabricated and tested in this work. Preformed CNF thin film or nanopaper, made of dense and entangled nanofiber networks, was molded on the surface of GFRPC as a surface protection layer by vacuum-assisted resin transfer molding. A fivefold improvement in sand erosion resistance in terms of sand erosion rate, and up to 24% improvement in flexural strength were achieved after the incorporation of CNF nanopaper onto thin GFRPC. The CNF nanopaper-enhanced GFRPC showed an EMI shielding of 33–40 dB within a frequency range of 30 MHz to 1.5 GHz. This multifunctional composite material shows good potential for use in wind power industry, commercial electronics housings, and the automotive industry.
      PubDate: 2017-06-02T00:25:38.50368-05:0
      DOI: 10.1002/adv.21846
       
  • Development and characterization of pH-responsive polyethylene
           glycol-co-poly(methacrylic acid) polymeric network system for colon target
           delivery of oxaliplatin: Its acute oral toxicity study
    • Authors: Kashif Barkat; Mahmood Ahmad, Muhammad Usman Minhas, Ikrima Khalid, Bushra Nasir
      Abstract: An oral route of administration is a most acceptable route for a patient, so we designed chemically cross-linked polyethylene glycol-co-poly(methacrylic acid) oral hydrogels (PEGMA 4000) by free radical polymerization method for pH-responsive colon target delivery of oxaliplatin (OXP). Polyethylene glycol (PEG 4000) was cross-linked chemically with methacrylic acid (MAA) in distilled water. Ammonium peroxodisulfate (APS) and N, N-methylene bisacrylamide (MBA) were used as initiator and cross-linker respectively. OXP was loaded in prepared hydrogels. FTIR, DSC, TGA, SEM, and XRD were conducted for characterization of developed hydrogels which endorsed the formation of new polymeric network. The pH-sensitive behavior of hydrogels was observed by swelling dynamics and equilibrium swelling ratio at low (1.2) and higher pH (7.4). Toxicity study was also conducted on rabbits to evaluate toxicity and biocompatibility of developed carrier system to biological system. Hydrogels with higher PEG 4000 concentration showed maximum swelling and higher drug loading at 7.4 pH. Toxicity study confirmed the developed hydrogels as non-toxic and biocompatible for biological system. Resultantly, these hydrogels can become an excellent candidates for colon targeting of OXP to treat colorectal cancer with no toxicity.
      PubDate: 2017-05-25T01:55:32.710437-05:
      DOI: 10.1002/adv.21840
       
  • Design of the printing pattern on film for three-dimensional molded
           interconnect devices
    • Authors: Ren Hao Liu; Wen-Bin Young, Hsu Pe Ming
      Abstract: This article discusses the application of an in-mold decoration (IMD) technology for the development of three-dimensional molded interconnect devices (3D-MID). The 3D-MID process uses the film printing technology to print the circuit pattern on a plastic film, and then deform it to the shape of the component by thermoforming. Then, the plastic film is placed inside the mold cavity for injection molding, and is attached to the surface of the component after molding. Experiments were performed for the 3D-MID process using a semisphere shape. A simple geometric model was also proposed to correlate the printed film patterns before and after the thermoforming. The geometric model will be used to design the required printing pattern on a 2D film for a given 3D pattern on a component.
      PubDate: 2017-05-22T06:25:37.76316-05:0
      DOI: 10.1002/adv.21830
       
  • Molecularly imprinted fluorescent probe based on hydrophobic CdSe/ZnS
           quantum dots for the detection of methamidophos in fruit and vegetables
    • Authors: Xueyan Liu; Qiurui Liu, Feifan Kong, Xuguang Qiao, Zhixiang Xu
      Abstract: In this study, a molecularly imprinted polymer (MIP)-fluorescent probe based on hydrophobic CdSe/ZnS quantum dots (CdSe/ZnS@MIP) was designed and synthesized by bulk polymerization for detecting methamidophos (MAP). The CdSe/ZnS@MIP was characterized by Fourier-transform infrared spectroscopy, thermo-gravimetric analysis and adsorption properties, and it exhibited good adsorption capacity and fluorescent stability, and excellent selectivity. Under optimal conditions, the fluorescence showed a good linear decrease in the range of 3.50 × 10−7–0.71 × 10−3 mol/L with a correlation coefficient of 0.995. The limit of detection of the fluorescent probe was 9.16 × 10−8 mol/L, and the relative standard deviation of the method for nine replicate analyses of 4.0 × 10−6 mol/L MAP was 4.1%. Apple and pear samples spiked with MAP at three levels were extracted and determined by the presented method with good recoveries (89.7%–94.9%). The accuracy of the method was verified by gas chromatography for the detection of kidney beans, leek and cucumber samples, and no significant difference was observed for the results of two methods.
      PubDate: 2017-05-22T02:00:32.702102-05:
      DOI: 10.1002/adv.21838
       
  • Application of poly(methyl methacrylate
           -co-γ-methacryloxypropyltrimethoxysilane)/silica modified TiO2
           nanocomposites for anti-pollutant properties
    • Authors: Mehdi Hatami; Nader Djafarzadeh, Hamed Hasanabadi
      Abstract: In this research, the effects of organic-inorganic hybrid nanocomposites as novel nanostructure additives in paint compositions were studied. The silica modified TiO2 nano structure was prepared by using sol–gel method. The TEM analysis indicated that these particles were in the range 10–15 nm. The organo silicone containing polymer was prepared by free radical polymerization process. The prepared polymer/mixed metal oxides nanocomposites were fabricated and demonstrated as nanostructure additives. The prepared nanocomposite was introduced into the road marking material formulation. In the first part of the current study, the prepared samples were evaluated by quality control experiment such as compatibility and color visualization tests. Also specific experiments such as hydrophobicity, adhesion, exposure to weathering conditions, self-cleaning nature of the samples, gloss appearance, hardness of the prepared samples, anti-pollution investigation, moisture resistance, and heat-cold cycle's tests were evaluated. The environmental issue of the road marking material and also the dirtiness removal efficiency by using nanostructure coating was investigated. The prepared samples showed 4–7 mg weight loss per hundred square centimeters during the exposure to 300 h by 313 nm UVB irradiation. The best photocatalytic performance in road marking application was found for NA 3% sample.
      PubDate: 2017-05-20T01:40:32.049367-05:
      DOI: 10.1002/adv.21842
       
  • Chemo-enzymatic synthesis of dendronized polymers for cyanine dye
           encapsulation
    • Authors: Shiv Kumar; Katharina Achazi, Kai Licha, Priyanka Manchanda, Rainer Haag, Sunil Kumar Sharma
      Abstract: Cyanine 3 is an amphiphilic fluorescent dye used in optical imaging, bioengineering, and for cellular internalization. However, the applications of the dye are limited due to its poor aqueous stability, aggregation tendency, and lack of selectivity. To address these issues, we have developed PEG and azidotriglycerol based dendronized polymers using Novozym 435 as a biocatalyst under solvent free conditions. The resulting polymer having azido and hydroxyl functionalities available in the backbone were further grafted with alkyl chains and polyglycerol dendrons using esterification and ‘Click’ chemistry approach. These polymers form stable micelles at micromolar concentration. All the polymers were characterized from their spectral data and their tendency to encapsulate cyanine 3 dye studied using UV-Vis and fluorescence spectroscopy. The cytotoxicity study of the polymers performed against A549 cell lines suggests them to be nontoxic up to a concentration of 500 μg/ml.
      PubDate: 2017-05-15T01:07:07.683415-05:
      DOI: 10.1002/adv.21839
       
  • Synthesis and characterization of a high performance polyamide-6 elastomer
           based on poly(ether-block-amide) multiblock copolymer by reactive
           processing in torque rheometer
    • Authors: Yuan Lei; Changbing Li, Xiaowei Fu, Jingxin Lei, Changlin Zhou
      Abstract: The polyamide-6 based poly(ether-block-amide) (PEBA) multiblock copolymers were reactively prepared in typical processing equipment, torque rheometer. The reactive processing conditions of PEBA were discussed in details on the base of the tensile strength as the main quantization parameter and the torque rheological curves. The optimized reaction temperature, reaction time, and rotational speed were 150°C, 10 min, and 40 rpm respectively. The chemical structure, tensile properties, thermal transition, thermal stability, water absorption, and solubility in organic solvents of PEBA prepared in optimized reaction conditions were characterized by Fourier transform infrared spectroscopy, tensile testing, differential scanning calorimetry, thermogravimetric analysis, and soaking testing in water and organic solvents. The tensile strength and elongation at break of PEBA are 35.9 MPa and 580% respectively. The glass transition temperature and melting temperature of soft segment of PEBA are −50 and 15°C, respectively; the glass transition temperature and melting temperature of hard segment of PEBA are 50 and 140°C respectively. Meanwhile, the PEBA has low water absorption, robust organic solvent resistance, and good thermal stability. The optimization process of PEBA will give the deep understanding of reactive processing of polymer materials.
      PubDate: 2017-05-08T01:05:04.035672-05:
      DOI: 10.1002/adv.21837
       
  • Surface and proton conductivity properties of electrospun poly(vinyl
           butyral)/polyaniline nanofibers
    • Authors: Emre Baştürk; Emrah Çakmakçi, Seyfullah Madakbaş, Memet Vezir Kahraman
      Abstract: Proton-conductive electrospun nanofibers are promising potential materials for several advanced technological applications such batteries, sensors, and fuel cells. In this work, we prepared poly(vinyl butyral)/polyaniline (PVB/PANI) nanofibers via electrospinning and determined their proton conductivities. Structural characterization of the nanofibers was performed by FTIR analysis. Surface morphology of the nanofibers was determined by SEM and AFM. The addition of PANI significantly affected the fiber morphology, and over 90% reduction (with respect to neat PVB nanofibers) in the average nanofiber diameters was observed. Nanofiber mats were doped with polyphosphoric acid. The proton conductivity of the 2 wt.% PANI containing blend nanofibers was found as 18 × 10−6 S/cm at room temperature and at 100% humidity.
      PubDate: 2017-05-08T00:33:55.851469-05:
      DOI: 10.1002/adv.21836
       
  • Effect of blast furnace slag content on mechanical and slurry abrasion
           behavior of needle-punched nonwoven fabric reinforced epoxy composites
    • Authors: Prabina Kumar Patnaik; Sandhyarani Biswas
      Abstract: This article reports on mechanical and slurry abrasion response of a new class of material developed by reinforcement of blast furnace slag (BFS) in needle-punched nonwoven polyester fabric epoxy composites. These epoxy-based composites are prepared by the hand-lay-up technique with the variation of BFS content (0, 5, 10, and 15 wt. %) and at constant fiber loading. It is observed that the mechanical properties of the composites are improved significantly with the incorporation of filler. However, the properties like tensile, flexural and inter-laminar shear strength are reduced beyond 10 wt. % of filler loading. Abrasive wear behavior of these composites is studied in the slurry environment by a slurry abrasion test rig (ASTM G105). The specific wear rate of composites under a steady-state condition with respect to normal load and sliding velocity is found to decrease with the increase in filler loading. Further, experimental design through Taguchi's L16 orthogonal array is applied to determine the optimal parametric combination which reduces the wear rate. The parametric combination among sliding velocity of 0.93 m/s, normal load of 30 N, sliding distance of 600 m, silica sand size of 100 μm and filler loading of 5 wt. %, produces an optimum specific wear rate. The morphological study is conducted on abraded composite surfaces by using scanning electron microscopy (SEM) and possible wear mechanisms responsible for wear have been discussed.
      PubDate: 2017-05-02T10:49:51.264891-05:
      DOI: 10.1002/adv.21835
       
  • Effect of maleic anhydride-grafted polypropylene on the flow orientation
           of short glass fiber in molten polypropylene and on tensile properties of
           composites
    • Authors: Hideyuki Uematsu; Yu Suzuki, Yoshiyuki Iemoto, Shuichi Tanoue
      Abstract: Composites of polypropylene (PP) and PP blended with maleic anhydride-grafted polypropylene (MAPP) reinforced with short glass fibers were prepared via extrusion compounding and injection molding techniques. The fiber length did not significantly change irrespective of the presence of MAPP after compounding and injection molding. However, the tensile strength of PP/fiber showed significant improvement after MAPP addition. The interfacial shear strength between PP and fiber increased with the addition of MAPP. Examination of the failure surface of a dumbbell specimen after tensile testing confirmed that the fiber highly orientated in the flow direction in the PP/MAPP matrix. The tensile strength enhancement was attributed to the improvement of the interfacial shear strength between PP and fiber. Moreover, in the injection molding process, there was high orientation of the fiber in the flow direction when there was MAPP. We concluded that the presence of MAPP causes increased orientation of the fiber.
      PubDate: 2017-04-27T11:12:28.713727-05:
      DOI: 10.1002/adv.21834
       
  • Hybrid anion exchange membranes with self-assembled ionic channels
    • Authors: Na Liang; Yufei Tu, Jing Xu, Dongzhi Chen, Hongwei Zhang
      Abstract: A novel strategy for fabricating nanocomposite anion exchange membranes (AEM), which can construct self-assembled ionic channels via in situ Menshutkin reaction, is proposed. The TEM image of a nanocomposite AEM based on chloromethylated polysulfone (CMPSF) and functionalized polyhedral oligomeric silsesquioxane (POSS) confirms the existence of core-shell clusters. The ionic conductivity of these nanocomposite AEMs shows a notable increase when the content of functionalized POSS exceeds the percolation threshold. Furthermore, the optimized nanocomposite AEM has higher ionic conductivity than the control AEM with similar ion-exchange capacity due to the well-developed morphology.
      PubDate: 2017-04-24T04:45:30.818681-05:
      DOI: 10.1002/adv.21831
       
  • Synergistic effects of carbon black and carbon nanotubes on the electrical
           resistivity of poly(butylene-terephthalate) nanocomposites
    • Authors: Andrea Dorigato; Marco Brugnara, Alessandro Pegoretti
      Abstract: In this study, novel electrically conductive polymeric nanocomposites based on polybutylene terephthalate (PBT) filled with commercial carbon black (CB) and carbon nanotubes (CNTs) at different relative ratios have been investigated. Field emission scanning electron microscope (FESEM) analysis revealed how a good nanofiller dispersion was obtained both by introducing CB and CNT. Melt flow index measurements highlighted that the processability of the nanocomposites was heavily compromised at elevated filler amounts, and the viscosity percolation threshold was established at 3 wt% for CNTs and between 6 and 10 wt% for CB nanocomposites. Differential scanning calorimetry (DSC) measurements evidenced how the presence of CNT slightly increased the glass transition temperature of the materials, and an increase of 12°C of the crystallization temperature was obtained with a CNT amount of 6 wt%. Also the crystalline fraction was increased upon CNT addition. Electrical resistivity measurements evidenced that the most interesting results were obtained for nanocomposites with a total filler content of 6 wt% and a CNT/CB relative amount equal to 2:1. The synergistic effect obtained with the combination of both nanofillers allowed the achievement of a rapid surface heating through Joule effect even at applied voltages of 2 V.
      PubDate: 2017-04-21T23:36:28.295175-05:
      DOI: 10.1002/adv.21833
       
  • Issue Information
    • Pages: 397 - 400
      PubDate: 2017-10-13T06:47:48.921725-05:
      DOI: 10.1002/adv.21769
       
  • News from the Polymer Processing Institute
    • Pages: 525 - 528
      PubDate: 2017-10-13T06:47:49.270486-05:
      DOI: 10.1002/adv.21768
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2016