Subjects -> MANUFACTURING AND TECHNOLOGY (Total: 362 journals)     - CERAMICS, GLASS AND POTTERY (31 journals)    - MACHINERY (34 journals)    - MANUFACTURING AND TECHNOLOGY (223 journals)    - METROLOGY AND STANDARDIZATION (5 journals)    - PACKAGING (19 journals)    - PAINTS AND PROTECTIVE COATINGS (4 journals)    - PLASTICS (42 journals)    - RUBBER (4 journals) PLASTICS (42 journals)
 Showing 1 - 32 of 32 Journals sorted alphabetically ACS Applied Polymer Materials       (Followers: 9) Acta Polymerica       (Followers: 9) Additives for Polymers       (Followers: 20) Advanced Industrial and Engineering Polymer Research       (Followers: 4) Advances in Polymer Technology       (Followers: 13) Chinese Journal of Polymer Science       (Followers: 9) Cirugia Plastica Ibero-Latinoamericana European Polymer Journal       (Followers: 44) International Journal of Biobased Plastics       (Followers: 2) International Journal of Polymeric Materials       (Followers: 6) International Polymer Processing       (Followers: 1) Iranian Journal of Polymer Science and Technology       (Followers: 1) Journal of Applied Polymer Science       (Followers: 115) Journal of Inorganic and Organometallic Polymers and Materials       (Followers: 8) Journal of Polymer Research       (Followers: 7) Journal of Polymer Science Part C : Polymer Letters       (Followers: 5) Journal of Polymers and the Environment       (Followers: 1) Majalah Kulit, Karet, dan Plastik Microplastics and Nanoplastics Plastic and Polymer Technology       (Followers: 40) Plastic and Reconstructive Surgery       (Followers: 30) Plastics Engineering Polymer       (Followers: 86) Polymer Bulletin       (Followers: 7) Polymer Engineering & Science       (Followers: 15) Polymer Science Series B       (Followers: 4) Polymer Science Series C       (Followers: 3) Polymer Science Series D       (Followers: 3) Polymer Science, Series A       (Followers: 3) Polymer-Plastics Technology and Materials       (Followers: 5) Reinforced Plastics       (Followers: 17) SPE Polymers
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 Journal of Polymers and the EnvironmentJournal Prestige (SJR): 0.562 Citation Impact (citeScore): 2Number of Followers: 1      Hybrid journal (It can contain Open Access articles) ISSN (Print) 1566-2543 - ISSN (Online) 1572-8919 Published by Springer-Verlag  [2469 journals]
• Enhanced Functional Properties of Biodegradable Polyvinyl
Alcohol/Carboxymethyl Cellulose (PVA/CMC) Composite Films Reinforced with
l-alanine Surface Modified CuO Nanorods

Abstract: Herein, we described novel biogenic preparation of the CuO nanorods and its surface modification with l-alanine amino acid accelerated by microwave irradiation. The effect of surface functionalized CuO nanorods on the physico-mechanical properties of polyvinyl alcohol/carboxymethyl cellulose films were investigated through various characterization techniques. The tensile strength was improved from 28.58 ± 0.73 to 43.40 ± 0.93 MPa, UV shielding ability and barrier to the water vapors were highly enhanced when PVA/CMC matrices filled with 8 wt% of CuO-l-alanine. In addition, the prepared films exhibited acceptable overall migration limit and readily undergoes soil burial degradation. Nevertheless, CuO-l-alanine incorporated films showed potent antioxidant activity against DPPH radicals and had high antibacterial activity against Staphylococcus aureus and Escherichia coli, and antifungal activity against Candida albicans and Candida tropicalis. Furthermore, the nanocomposite films showed negligible cytotoxic effect on HEK293 and Caco-2 cell lines. In these contexts, the developed nanocomposite films can be implementing as an active food packaging material. Graphical
PubDate: 2022-01-17

• Fe(III) Complexed Polydopamine Modified Mg/Al Layered Double Hydroxide
Enhances the Removal of Cr(VI) from Aqueous Solutions

Abstract: Herein, we report the preparation of Fe(III) complexed polydopamine modified Mg/Al layered double hydroxides composite material (LDHs@PDA-Fe(III)) and its application to the removal of Cr(VI) in aqueous solution. LDHs@PDA-Fe(III) was characterized and analyzed by field-emission scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM–EDS), Fourier transformed infrared (FTIR), X-ray diffraction (XRD), X-ray photoelectron (XPS). The adsorption performance was studied through a series of adsorption experiments. Investigate the effects of pH, time, temperature, concentration and other factors. When C0 = 800 mg/L, T = 308 k and pH 3, the maximum adsorption capacity obtained in the experiment was 683.4 mg/g. In addition, after 5 adsorption cycles, LDHs@PDA-Fe(III) still shows excellent adsorption capacity and stability. Combining adsorption experiments and characterization analysis, it is inferred that the adsorption of Cr(VI) by LDHs@PDA-Fe(III) is the result of the synergistic effect of multiple adsorption mechanisms. Therefore, the efficient removal capacity and excellent stability make LDHs@PDA-Fe(III) an ideal adsorbent for removing Cr(VI) from aqueous solutions.
PubDate: 2022-01-17

• Scalable Manufacturing Green Core–Shell Structure Flame Retardant, with
Enhanced Mechanical and Flame-Retardant Performances of Polylactic Acid

Abstract: As a plastic that can be prepared from biomass resources, polylactic acid (PLA) has the characteristics of being degradable and renewable, and has shown great potential in replacing petroleum-based polymer materials. However, PLA material is flammable, the droplet phenomenon during combustion is still a disadvantage of PLA applications. In this research, a core–shell structure flame retardant was prepared based on polyacrylamide (PAM)/sodium alginate (SA) coated ammonium polyphosphate (APP) via layer-by-layer assembly using water as the assembly medium. The prepared core–shell flame retardant APP@PAM@SA-nDL (where “DL” is the PAM&SA double layer, and “n” represents 1-3DL) was molten compounded with PLA to improve its flame retardancy. APP@PAM@SA-nDL is added to PLA, which not only improves the flame retardancy of PLA composites, but also significantly improves the toughness, and the flame retardancy, flame retardant mechanism, mechanical performance and toughening mechanism of PLA composites were systematically studied. Among the core–shell flame retardants with different layers, the addition of APP@PAM@SA-3DL gives PLA composites excellent flame retardancy and tensile properties. Due to the formation of the cross-linked polymer network structure, 5% APP@PAM@SA-3DL can increase the elongation at break of PLA composites from 19.82 to 294.5%. In addition, 10% of APP@PAM@SA-3DL made the UL-94 of PLA composite materials reach V-0 level and increased the LOI from 19.7% (neat PLA) to 29.2%. The analysis of the carbon layer shows that the excellent flame-retardant performance of PLA composites can be attributed to the formation of a dense carbon layer during condensation and the dilution effect of P-containing free radicals, forming a flame-retardant mechanism with a condensed phase as the main component and a gas phase as a supplement. This high toughness flame-retardant PLA composite material has broad application prospects in the textile field. Graphical
PubDate: 2022-01-16

• Ionic Dye Removal Using Solvent-Assisted Ionic Micellar Flocculation

Abstract: The environmental impacts caused by dyes in industrial wastewater are incalculable, due to their adverse effects on the ecosystem and human life, especially when discarded at illegal levels. The ionic micellar flocculation process to remove metals and organic compounds has proven to be an innovative and efficient alternative in the removal of pollutants from aqueous solutions. In this respect, an anionic surfactant, composed of a mixture of surfactants derived from coconut oil and animal fat, was used to remove the ionic dyes methylene blue (MB) and Acid Red 57 (AR57) from an aqueous medium. During extraction trials, the use of a soap base anionic surfactant at concentrations below the critical micelle concentration (CMC) promotes the formation of an insoluble surfactant (cationic dye-anionic monomer), acting as an ionic flocculant by monomers. On the other hand, at concentrations above the CMC, adding calcium ions to an aqueous solution allowed the formation of micellar flocs capable of removing dye, reaching maximum extraction percentages of 60% of MB and 90% of AR57. The influence of initial dye concentration, surfactant concentration, pH and the presence of electrolytes demonstrated that the interaction mechanisms between the dyes and micelles are based on electrostatic interactions and/or micellar solubilization, confirmed by determining the diameter of micellar aggregates. Solvent-assisted ionic micellar flocculation was applied to increase MB removal efficiency from 26 to 91%.
PubDate: 2022-01-16

• Optimization and Characterization of Bioactive Biocomposite Film Based on
Orange Peel Incorporated with Gum Arabic Reinforced by Cr2O3 Nanoparticles

Abstract: In this paper, the effect of adding gum arabic at levels of 0–5%, and chromium oxide nanoparticles (Cr2O3 NPs) at levels of 0–3%, were optimized on orange peel-based films by response surface methodology. The obtained results reveal a significant increase in water vapor permeability, weight loss, tensile strength, and Young's modulus of film samples by increasing the percentage of both gum and nanoparticles (p < 0.05). Moreover, the addition of gum arabic and Cr2O3 NPs decreases the thickness, water-solubility, L*, a*, b* indexes while increasing the elongation to the breaking point. Furthermore, the moisture content of the film samples was decreased by the addition of nanoparticles, however, the addition of gum arabic increased this parameter. The obtained results from the morphology of the samples indicated an increase in both roughness and cracks by increasing the percentage of nanoparticles as well as creating a smooth surface with the addition of gum arabic. Besides, the results of Fourier-transform infrared spectroscopy revealed no new peak in the prepared samples, as compared to the control sample. The results of X-ray diffraction indicated that the addition of gum arabic and nanoparticles simultaneously caused the formation of new crystals and increasing the crystallinity of the films. Based on Thermogravimetric analysis results, the thermal stability of films containing the nanoparticles increased, as compared to the control sample. In the meantime, the addition of gum and nanoparticles increased the antimicrobial properties of the film samples, as compared to the control. Overall, those films created by the orange peel including gum arabic and Cr2O3 NPs could enhance the mechanical properties and water vapor permeability of the samples.
PubDate: 2022-01-15

• Development and Characterization of the Reinforced Soy Protein
Isolate-Based Nanocomposite Film with CuO and TiO2 Nanoparticles

Abstract: The present study aimed to develop and characterize the soy protein isolate (SPI) nanocomposite film incorporated with CuO and TiO2 nanoparticles (NPs) for application as an active packaging system. The morphology study of films showed that the incorporation of NPs caused the formation of a dense and compact structure. The creation of interactions among SPI matrix and NPs was approved via Fourier transforms infrared structural conformations. The mechanical properties of SPI-based film were improved through the incorporation of NPs. The film sample incorporated with CuO and TiO2 NPs at 1% of concentration showed the lowest water vapor permeability, moisture content, and water solubility. Additionally, the incorporation of both NPs provided antioxidant activity in the SPI-based films. The L* color parameter was significantly (p < 0.05) decreased with the incorporation of NPs, but the a* and b* color parameters were increased. Moreover, the incorporation of CuO and TiO2 NPs increased the opacity in the SPI-based films. In conclusion, the incorporation of CuO and TiO2 NPs provided suitable physicochemical properties for SPI-based films and the developed nanocomposite films could be applied as an active packaging system for different foodstuffs.
PubDate: 2022-01-15

• A Compatible Interface of Wheat Straw/Polylactic Acid Composites
Collaborative Constructed Using KH570–Nano TiO2

Abstract: Poor interfacial compatibility between wheat straw and polylactic acid (PLA) remains a problem that directly affects the overall performance of wheat straw/PLA composites, thereby reducing the scope of application of these types of composites. To address this concern in this study, a silane coupling agent, KH570, and nano TiO2 were used to synergistically construct wheat straw/PLA composites with compatible interfaces. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry were conducted to investigate the underlying mechanism of synergistic modification. Analysis of the mechanical and water resistance properties indicates that the agglomeration of nano TiO2 in the synergistically modified composites is reduced, leading to the improved interfacial compatibility of the composites, tightened two-phase combination, and weakened stress concentration. Consequently, the mechanical strength and water resistance of the composites are effectively enhanced. Compared with unmodified composites, the blending and tensile strength of the synergistically modified composites increased by 25.4% and 44.7%, respectively, and its 96 h water absorption rate decreased by 17.4%. Analysis of the thermal stability and crystalline structure showed that the crystallinity of the synergistically modified composites was significantly enhanced, and the thermal stability was improved. Analyses of the rheological properties showed that the storage modulus (G′) of the synergistically modified composites was significantly improved under strain sweep, indicating that the two phases of the synergistically modified composites possessed enhanced bonding strength and internal structural stability. Frequency scanning showed that the complex viscosity (η*) of the synergistically modified composites exhibited the greatest improvement, indicating that a compatible composite interface was constructed by synergistic modification; moreover, the strong physical crosslinking effect and the nano TiO2 interparticle interaction friction hindered the flow of the composites. In this paper, for the first time, a silane coupling agent, KH570, was used to construct wheat straw/PLA composites with a compatible interface utilizing nano TiO2 to enhance the overall properties of the composite, which provides favorable properties for applications of wheat straw/PLA composites. Graphical
PubDate: 2022-01-15

• Investigating the Mechanical, Morphological, and Acoustic Properties of
the Phenolic Aerogel/Flexible Polyurethane Foam Composite

Abstract: The present study investigated the effects of adding phenolic aerogel (PA) to flexible polyurethane foam on the sound absorption coefficient, morphology, and mechanical properties. PA was synthesized under solvent saturated vapor atmosphere, and then it was added to the polymer matrix in the form of particles with different weight percentages (i.e., 0.25, 0.50, and 0.75 wt%). The examination of the cell structure and the pores of the composite using electron microscopy showed that by increasing the concentration of PA, the number of open pores and the interconnection between the cells increased. The PA/flexible polyurethane foam composite $$\left(\text{PA}/\text{FPUF} \right)$$ with 0.50 wt% of PA exhibited the highest sound absorption coefficient in the low-frequency range due to the regular cell structure and the small size of the cells. Moreover, the results showed that in addition to their impact on the morphology, PA particles could be useful in improving the mechanical properties of FPUF by increasing its Young’s modulus. Graphic
PubDate: 2022-01-14

• Reinforcing Paper Strength with High Viscosity Aminated Cellulose
Nanocrystal by Forming Nanocrystal Networks

Abstract: Higher tensile and bursting strength are paramount concerns in paper-based packaging materials. Herein, the aminated cellulose nanocrystal (A-CNC) was synthesized by the amination reactions firstly, and the base paper was reinforced via coating hydroxypropyl methylcellulose (HPMC) and A-CNC. The surface morphology and tensile strength of the coated composite paper were characterized and the rheological performance of A-CNC was also investigated. The results clearly demonstrated that coating of HPMC/A-CNC significantly increased the dry tensile strength of composite paper by 1.035 times (32.88 MPa) as compared with base paper (16.16 MPa). In addition, the paper strength as coated with A-CNC was also higher than that of unmodified CNC, which was attributed to the improvement of viscosity of A-CNC. The composite papers coated HPMC/A-CNC showed a great potential in packaging applications with higher mechanical strength.
PubDate: 2022-01-13

• Electrospun Composite Nanofibers Based on Poly (ε-Caprolactone) and
Styrax Liquidus (Liquidambar orientalis Miller) as a Wound Dressing:
Preparation, Characterization, Biological and Cytocompatibility Results

Abstract: In this study, styrax liquidus (sweet gum balsam) extracted from Liquidambar orientalis Mill. incorporated PCL fibrous scaffolds were prepared using the electrospinning method. The effects of the styrax liquidus content on the prepared scaffolds were investigated using different physico-chemical and morphological analyses. Then, the styrax-loaded nanofibers were examined for their antioxidant activity, anti-biofilm, metal chelating, antimicrobial and DNA cleavage properties. The results obtained from these studies showed that the nanofibers exhibited effective biological activity depending on the weight ratio of the styrax liquidus. In light of the data obtained from the characterization and biological studies, a sample with high ratio of balsam was built for determining the cytocompatibility analysis in vitro. The cytotoxicity studies of the selected membrane were conducted using mouse embryonic fibroblast cells. The fibrous scaffolds lead to increase the cell number as a result of high viability. According to the results, we propose a novel biocompatible electrospun hybrid scaffold with antioxidant and antimicrobial properties that can be used as wound healing material for potential tissue engineering applications.
PubDate: 2022-01-13

• Starch-Chitosan Hydrogels for the Controlled-Release of Herbicide in
Agricultural Applications: A Study on the Effect of the Concentration of

Abstract: Present work aims to synthesize the herbicide-loaded bio-based hydrogels and study the release mechanism. The different ratios of starch and chitosan were chosen as the bio-based resources to form the hydrogel matrix with varying concentrations of two crosslinkers. The synthesized hydrogels were characterized using Fourier transform infrared spectroscopy for reaction completion. Thermogravimetric analysis provided information about the obtained hydrogels’ thermal stability, suggesting the tremendous positive impact of chitosan concentration. Differential scanning calorimetry was done to know the initial trapped water release from the hydrogel matrix and relate the structures with the release rate study. Further, scanning electron microscopy revealed the morphology of the obtained hydrogels and could establish the relation with the corresponding hydrogel structures. The equilibrium swelling degree, release dynamics of atrazine, and diffusion mechanism have also been evaluated. The swelling significantly affected the release behavior, and the hydrogels prepared with glyoxal showed the lowest release rate of atrazine, the release vitality reaching 500 h. Until the concentration of starch and chitosan were equal, release followed the Fickian diffusion mechanism, and as soon as the concentration of chitosan increased, non-Fickian diffusion proceeded.
PubDate: 2022-01-12

• Curcumin- A Bio-based Precursor for Smart and Active Food Packaging
Systems: A Review

Abstract: The current scenario of global trends impacts the way in which food is consumed and packed, meaning that change is inevitable and just around the horizon in terms of making food packaging eco-friendlier and more sustainable. Scientific advancements over the past decades have led to a wide spectrum of solutions to this problem in terms of smart, active, and antimicrobial packaging systems. The increasing demand for sustainability paves the way as a golden opportunity for these systems as they have the ability to incorporate biobased precursors like curcumin through advancements in the field of the invisible enabler, biochemistry. Investigating the properties of curcumin as a bioagent can change the dynamics of the current food packaging industry, owing to its non-toxic and eco-friendly nature and a plethora of pharmacological properties. Curcumin is the principal curcuminoid of the golden spice turmeric. Being derived from a ferulic acid, it shows excellent antimicrobial properties against bacterial pathogens like Staphylococcus aureus, Listeria monocytogenes, and Escherichia coli, and fungal cultures such as Penicillium spp. and Candida albicans. This makes it a potential agent in the food packaging industry and used as a natural food additive, dietary supplement, and pH indicator. Curcumin encapsulation has been explored with polymer matrices like polyvinyl alcohol [PVOH], low-density polyethylene [LDPE], polyvinyl acetate [PVAC], polylactic acid [PLA], etc. It has also been studied with metals like zinc as a complex which demonstrated an increase in the bioavailability of curcumin. This article aims to further explore the potential applications of curcumin in eco-friendly and antimicrobial packaging systems, and understand its importance as a bioagent. Graphical
PubDate: 2022-01-11

• Synthesis of Biobased Soft-Packaging Polyesters from 2,5
Thiophenedicarboxylic Acid

Abstract: Demand for light-packaging materials for food and beverages is on the rise globally, especially in developing countries where several depend on packaged food. Furthermore, poly(ethylene terephthalate) (PET) a semi-crystalline thermally stable polyester, is widely used for carbonated soft drink, water and juice bottles, but shows a poor degradability properties after their lifespan. In this investigation, a series of novel random partially degradable poly(carbonate-co-esters) (PTB/PTBCn) containing 2,5-thiophenedicarboxylic acid (TDCA), and different amounts of bis(2-hydroxyethoxy)benzene (BHEB) and 1,4-cyclohexanedimethanol (CHDM) sub-units were successfully synthesized via a two-step melt polymerization as a facile and green semi-continuous process. The copolymers were thermally stable with tunable Tg values ranging from 47 to 71 °C, while their 5% decomposition temperature (Td, 5%) under N2 varied from 463 to 432 °C. Herein, focus was made on the synthesis of eco-friendly polyesters with satisfactory O2-gas barrier properties (5.5 cm3 mm/m2 × day × atm) at 25 °C suitable for most packaging applications. The mechanical and thermal analysis of PTB and PTBCn polyesters revealed excellent properties comparable to commonly used packaging materials such as poly(vinyl chloride), poly(lactic acid) and PET, whereby the incorporation of cyclohexane (CHDM) and phenyl (BHEB) rings units greatly enhanced the thermal and mechanical properties, transparency, oxygen permeability, and biodegradability of these polyesters. Graphical
PubDate: 2022-01-10

• Ionically Crosslinked Chitosan/Tragacanth Gum Based Polyelectrolyte
Complexes for Antimicrobial Biopackaging Applications

Abstract: The novel polyelectrolyte complexes (PEC) were prepared by mixing different Wt% of Tragacanth gum (TG) to Chitosan (CS) and systematic evaluation of multifunctional properties of colloidal solution and films was carried out. The formation of PEC was dependant on the order of mixing of solutions. Particle size analysis, Zeta potential and FTIR confirmed the formation of PEC. SEM studies revealed the homogeneous distribution of colloidal particles on the surface. Contact angle analysis, water solubility, and moisture adsorption studies revealed the hydrophobicity of films. Further, the water vapor transmission rate and oxygen permeability of the control film was improved significantly and found to be in the range of polyethylene terephthalate by ionic crosslinking of TG and CS. Ionic crosslinking significantly enhanced antibacterial, antioxidant activity and rate of degradation in soil. Obtained biofilms exhibited far better preservation ability than commercial polyethylene films. Hence, biofilms could be used in antimicrobial packaging applications. Graphical
PubDate: 2022-01-09

• Calcined Oil Shale Semi-coke for Significantly Improved Performance
Alginate-Based Film by Crosslinking with Ca2+

Abstract: Oil shale semi-coke (OSSC) is the residual solid waste after refining of oil shale, which principally contains organic matter and minerals. The common disposal method of OSSC (i.e., landfill) poses potential risk to the environment, ecology and human health due to its residual organic matter. Therefore, it is imperative to explore a green and efficient way to dispose and utilize OSSC, where calcination (removal of organic matter and activation of minerals) might be an effective method. Firstly, the effect of calcination on OSSC was systematically studied, found that the OSSC calcined at 500–700 °C can retain the regular lamellar and activated clay mineral (such as kaolinite) without organic matter. Then, the reinforcing ability of the calcined OSSC was evaluated by incorporating it into sodium alginate (SA) matrix to prepare composite films, and the Ca2+-crosslinking strategy was adopted to further improve the performance of the composite film. With the addition of 3 wt% of OCCS-500 (the OSSC calcined at 500 ℃), the tensile strength of the composite film can reach 17.6 MPa, which was much higher than that of pure SA film (10.6 MPa), and the tensile strength of Ca2+-crosslinking composite film was up to 65.2 MPa. Furthermore, the crosslinked composite film also exhibited excellent thermal stability, water-resistance and acid–alkali resistance. In general, this work laid a foundation for the utilization of OSSC from two aspects of solid waste resource utilization and environmental protection. Graphical abstract
PubDate: 2022-01-06

• Characterization of Lipopeptides Biosurfactants Produced by a Newly
Isolated Strain Bacillus subtilis ZNI5: Potential Environmental
Application

Abstract: Aiming the production of lipopeptides biosurfactants (BioS), we isolated a new strain identified as Bacillus subtilis ZNI5 from a hydrocarbon contaminated soil. Lipopeptides purification by anionic exchange chromatography and identification by Reverse Phase High Performance Liquid Chromatography–Mass Spectrometry (RP-HPLC–MS) permitted the selection of different homologues divided into four families. The first family corresponds to Surfactin isoforms with molecular weights of 1007, 1021 and 1035 Da; the second family correspond to Iturin isoforms with molecular weights of 1028, 1042 and 1056 Da; the third family correspond to a single isoform called Licheniformin with molecular weight of 1410 and the fourth family correspond to newly identified isoforms named Inesfactin with molecular weights of 973 and 987 Da. Regarding the functional properties of the ZNI5 BioS, it was characterized as a powerful surface-active agent that decreases the Surface Tension of water from 72 mN/m to about 32 mN/m with a CMC value of 350 mg/L more efficient than chemical surfactants (Triton X100; CTAB and SDS). Moreover, it has the capacity to disperse oil to about 80 mm at a concentration of 800 mg/L showing close efficiencies to the listed chemical surfactants. In addition, the physic–chemical characterization of the surface activities of ZNI5 BioS showed great thermal, pH and salts activity and stability enabling its use in the bioremediation fields and for diverse industrial applications.
PubDate: 2022-01-04

• Effect of Brown-Rotted Spruce as Lignin-Enriched Filler on the Properties
of Reinforced Polyurethane Foam

Abstract: The study investigated the effect of lignocellulosic biomass filler decayed by brown-rot fungi on the preparation and properties of polyurethane (PU) foam. The properties of brown-rotted spruce were characterized by microstructure, chemical composition, and hydroxyl value to examine the possibility of preparing polyurethane foam using brown-rotted spruce as filler. Brown-rotted spruce was a homogeneous material, mainly composed of lignin (80.36%) with a high content (284.5 mg KOH/g) of hydroxyl groups in structure that could participate in a chain reaction with isocyanate groups on the foaming process. In the study, PU foams were prepared successfully with the addition of brown-rotted spruce as filler in different concentrations (1–10 wt%). The results showed that the addition of brown-rotted spruce improved the physical properties (low density, low thermal conductivity, high water absorption) of PU foam. These properties showed a significant dependence on filler amount. The density decreased from 89.64 kg m−3 to 60.22 kg m−3 as the filler amount increased. Scanning electron microscope showed the cellular structure of PU foam was affected by the filler amount. PU foam with low addition amount (5 wt%) had homogeneous shapes and smaller cell shapes, resulting in the highest compressive strength (0.42 Mpa). Utilizing brown-rotted wood as a lignin-enriched filler is a simple and feasible way to improve the properties of PU foam. Graphical
PubDate: 2022-01-04

• Hydrophobic and Flame-Retardant Foam Based on Cellulose

Abstract: A study aimed to prepare cellulose-based hydrophobic, lightweight, and flame retardant foam composites. Cellulose was activated by phosphoric acid followed by blending with dolomite clay of different loading ratios. Gelatin/tannin as an adhesive system was used as a binder. A solution of the environmentally friendly silicone rubber (RTV) was applied onto foam samples via spray-coating to improve their water repealing performance, which was explored by investigating both of water contacting angle and wettability time of the coated foam samples. Flammability characteristics, thermal decomposition, surface morphology, and chemical structure of treated and untreated foams were investigated by flammability test, thermogravimetric analysis, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared. The fire retardancy of foam composites was optimized at low and medium loading of dolomite. Also, the addition of RTV improved the hydrophobicity of composites maintained the fire retardancy of composites with medium loading.
PubDate: 2022-01-04

• Polymers, the Light at the End of Dark Fermentation: Production of
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) by a Photoheterotrophic
Consortium

Abstract: In this study, the photoheterotrophic consortium C4 was used to produce the copolymer [P(3HB-co-3HV)]. PHA production was enhanced by using response surface methodology (RSM) to determine the effects of different concentrations of acetate and butyrate in mixtures (0.5–3 g L−1), ammonium sulfate and their combinations. This is relevant because PHA accumulation is stimulated by nitrogen limitation. The type and concentration of the substrate determines the monomeric composition and the PHA content (% per cell dry mass (CDM)). The RSM, carbon balance and metabolic behavior analysis results showed that at the lowest ammonium concentration, 0.1 g L−1, and when acetate was in a higher proportion than butyrate, biomass production was favored. In contrast, when the butyrate proportion was high, PHA production increased, reaching a highest production of 58% per CDM. The better conditions were evaluated in a 3-L reactor, and a maximum P(3HB-co-3HV) of 67% was determined. The predominant microbial population consisted of four major species, Macelibacteroides fermentans (37%), Rhodopseudomonas palustris (22%), Acinetobacter sp. (35%), and Clostridium propionicum (2%). Insights into the understanding of copolymer production by photoheterotrophic mixed cultures constitute the basis for developing coupled processes from organic residues. These microorganisms are worth studying since they produce a variety of valuable biotechnological products.
PubDate: 2022-01-04

• Precise Engineering of Lignin Incorporated Dextran/Glycol Nanomaterials
for Wound Dressings for the Care of Anorectal Surgery

Abstract: Lignin-loaded nanoparticles are versatile nanomaterials that may be used in wound healing properties. The current study describes a wound dressing formulation focused on Lignin-loaded dextran/glycol (DEX/GLY) nanoparticles. The Lignin-loaded dextran/glycol membranes were fabricated using Lignin solutions inside the dextran/glycol medium. The influence of various experimental conditions on dextran/glycol nanoparticle formations were examined. The sizes of dextran/glycol and Lignin-loaded dextran/glycol nanoparticles were examined through the HR-SEM. Moreover, the efficacy antibacterial activity of dextran/glycol and Lignin-loaded dextran/glycol nanoparticles was evaluated against the microorganisms gram-positive and negative. Furthermore, we observed the in vivo wound healing of wounds in skin using a mice model over a 14 days period. In this difference to the wounds of untreated mouse, quick healing was observed in the Lignin-loaded dextran/glycol nanoparticles-treated wounds with fewer injury. These results specify that Lignin-loaded dextran/glycol nanoparticles-based dressing material could be a ground-breaking nanomaterial having wound repair and implantations potential required for wound injury in anorectal surgery model, which was proven using an animal model. Graphic
PubDate: 2022-01-01

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