Showing papers in "Journal of Macromolecular Science, Part B in 2018"
TL;DR: A collagen-glycosaminoglycans scaffold, following chemical modifications, was prepared as an analog of the extracellular matrix (ECM) by a freeze drying method and was shown to be potentially useful for wound healing.
Abstract: In the present study a collagen-glycosaminoglycans scaffold, following chemical modifications, was prepared as an analog of the extracellular matrix (ECM) by a freeze drying method. Appropriate tes...
18 citations
TL;DR: In this article, a poly(acrylonitrile)/cellulose block copolymer (PAN-b-cell) was prepared by using a free radical initiating process and then the nitrile functional groups of the PAN blocks of the copolymers were tr...
Abstract: Poly(acrylonitrile)/cellulose block copolymer (PAN-b-cell) was prepared by using a free radical initiating process and then the nitrile functional groups of the PAN blocks of the copolymers were tr...
17 citations
TL;DR: In this paper, the electrical properties of epoxy polymer/carbon nanotubes composites were characterized using impedance spectroscopy in the frequency range between 1-Hz and 10-MHz and temperature range between 2-2
Abstract: The electrical properties of epoxy polymer/carbon nanotubes composites were characterized using impedance spectroscopy in the frequency range between 1 Hz and 10 MHz and temperature range between 2...
17 citations
TL;DR: In this paper, the authors considered hexamethylene diisocyanate (HED) as an optimum material for controlled release drug systems and tissue engineering scaffolds since they are tri-dimensional networks.
Abstract: Hydrogels are considered an optimum material for controlled release drug systems and tissue engineering scaffolds since they are tri-dimensional networks. In this work hexamethylene diisocyanate (H...
14 citations
TL;DR: In this paper, a cost-effective and safe method was used to synthesize polyethylene/ZnO nanocomposite films and their properties were investigated by using Fourier transform infrared analysis (FTIR) and ultraviolet-visible spectroscopy (UV-VIS).
Abstract: ZnO nanoparticles were synthesized through a cost-effective and safe method followed by fabrication and characterization of polyethylene/ZnO nanocomposite films and investigation of their properties. The morphology and size of the synthesized nanoparticles were evaluated by field emission scanning electron microscopy (FE-SEM). It was found that nanoparticles with a plate-like morphology with an average thickness of 50-70 nm were synthesized. The nanocomposites were characterized by using Fourier transform infrared analysis (FTIR) and ultraviolet–visible spectroscopy (UV-VIS). In addition, the effects of the amount of zinc oxide nanoparticles (ZnO-NPs) on the mechanical properties of the films and particles and their antibacterial properties against a gram-negative bacterium (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus) were investigated. In the case of nanoparticles, one more gram-positive bacterium (Staphylococcus aureus) was studied. The results demonstrated an inhibition...
14 citations
TL;DR: A bio-adsorbent was prepared by the crosslinking reaction of a tannin based phenolic resin and carboxymethyl cellulose with epichlorohydrin as crosslinker as mentioned in this paper.
Abstract: A bio-adsorbent was prepared by the crosslinking reaction of a tannin based phenolic resin and carboxymethyl cellulose with epichlorohydrin as crosslinker. The water absorption ratio of the adsorbe...
12 citations
TL;DR: In this paper, the effects of the GF on variations of structure and properties of the composites with aging time wer wer studied and long-term hydrothermal aging of polyamide 6 (PA6)/glass fibre composites was conducted.
Abstract: Long-term hydrothermal aging of polyamide 6 (PA6)/glass fibre (GF) composites was conducted and the effects of the GF on variations of structure and properties of the composites with aging time wer...
12 citations
TL;DR: In this paper, a polyamic acid (PAA) solution in xylene was prepared for electrospinning in order to fabricate fibers, however, jet breaking occurred at the point of the occurrence of whipping instability, resulting in forming micro-particles, which was an exceptional jet behavior compared with the general electro-spraying process that occurs directly from the surface of the polymer droplet.
Abstract: A poly(amic acid) (PAA) solution in xylene was prepared for electrospinning in order to fabricate fibers. However, jet breaking occurred at the point of the occurrence of whipping instability, resulting in forming micro-particles. This was an exceptional jet behavior compared with the general electro-spraying process that occurs directly from the surface of the polymer droplet. It is important to understand the mechanism of electrospinning and the instability of PAA in order to form fibers for mat deposition. Thus, the behavior of the jet breaking was clearly observed by a high-speed camera and the dynamic behavior of the jet was explored by an image analysis technique. Furthermore, polyacrylonitrile (PAN) was added to the PAA/xylene solution with various concentrations to change the elongation viscosity. Uniform diameter fibers were obtained by increasing the content of PAN to the level that the drag force between the polymer chains increased enough to overcome the drawing force. As a result the ...
11 citations
TL;DR: In this paper, a green/clean procedure was introduced to prepare an aerogel using biodegradable cellulose as feedstock and renewable choline butyrate as solvent.
Abstract: Developing biodegradable and biocompatible products to replace non-biodegradable petrochemical products is of great importance for supplementing rapidly diminishing oil resources and reducing environmental pollution. Based on this belief, the goal of this research was to introduce a green/clean procedure to prepare an aerogel using biodegradable cellulose as feedstock and renewable choline butyrate as solvent. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) were used to investigate the morphology, chemical structure and thermostability. The results indicated that the cellulose aerogel possessed a porous structure which was composed of randomly oriented cellulose sheets. The cellulose aerogel had an amorphous structure compared to the original cellulose (cellulose I), and displayed good thermal stability.
11 citations
TL;DR: The properties of polymer matrix composites are related not only to the chemical composition of the materials but also to the processing equipment used for their preparation which has a direct influence on their properties.
Abstract: The properties of polymer matrix composites are related not only to the chemical composition of the materials but also to the processing equipment used for their preparation which has a direct infl...
10 citations
TL;DR: A waterborne polyurethane (WPU) dye based on the fluorescent dye 4-diamino propane-N-allyl-1,8-naphthalimide was synthesized in this article.
Abstract: A waterborne-polyurethane (WPU) dye, based on the fluorescent dye 4-diamino propane-N-allyl-1,8- naphthalimide (WPU-DAN), was synthesized by attaching 4-diamino propane-N-allyl-1,8- naphthalimide (...
TL;DR: In this paper, the authors extracted amorphous silica from rice husk ash in the form of a powder and used it as a filler in rubbers and plastics for various applications.
Abstract: Rice husk is rich in amorphous silica which has found various applications as a filler in rubbers and plastics. In the research described here silica was extracted from rice husk ash in the form of...
TL;DR: In this paper, random terpolymers of poly(L-lactide-glycolide-e-caprolactone) (PLLGC) were prepared by ring-opening polymerization of L-Lactide, glycolide and e-Caprolacton monomers initiated with stannous octanoate.
Abstract: Random terpolymers of poly(L-lactide-glycolide-e-caprolactone) (PLLGC) was prepared by ring-opening polymerization of L-lactide, glycolide and e-caprolactone monomers initiated with stannous octanoate. Fourier transform infrared spectra, nuclear magnetic resonance and gel permeation chromatography were employed to characterize the obtained PLLGC terpolymers. The effects of polymerization temperature, reaction time, the amount of initiator and the polymerization pressure on the weight average molecular mass and polydispersity index of the PLLGC were investigated. In addition, the water contact angle of the PLLGC was also tested. The characterization of chemical structure showed that the PLLGC was successfully synthesized. For instance, a PLLGC terpolymer with a weight average molecular mass of about 12.435 × 104 Da and a polydispersity index of 1.28 was obtained when the polymerization was conducted with a molar ratio of monomer to initiator ([M]/[I]) of 2000, polymerization temperature of 140 °C, ...
TL;DR: The spontaneous transformation of the unstable tetragonal phase II to the stable twined hexagonal phase I of isotactic polybutene was shown in this paper at room temperature and atmospheric pressure.
Abstract: The spontaneous transformation of the unstable tetragonal phase II to the stable twined hexagonal phase I of isotactic polybutene – 1 at room temperature and atmospheric pressure was shown to proce...
TL;DR: In this paper, thermoplastic elastomers based on ethylene-vinyl acetate (EVA)/waste nitrile butadiene rubber powder (WNBRP) blends compatibilized by chlorinated polyethylene (CPE) were prepared by melt-com...
Abstract: Thermoplastic elastomers (TPEs) based on ethylene-vinyl acetate (EVA)/waste nitrile butadiene rubber powder (WNBRP) blends compatibilized by chlorinated polyethylene (CPE) were prepared by melt-com...
TL;DR: In this article, a two-step melt-compounding method was used to combine PA6/66 as a matrix and organoclay as a nanofiller through two-stage melting.
Abstract: Nylon copolymer/clay (NC) nanocomposites were prepared using PA6/66 as a matrix and organoclay as a nanofiller through a two-step melt-compounding method. It was shown that the organoclay flakes we...
TL;DR: In this article, the thermal phase transition temperatures of high (HMP) and low melting point (LMP) agarose gels were investigated by using UV-vis spectroscopy techniques.
Abstract: The thermal phase transition temperatures of high (HMP) and low melting point (LMP) agarose gels were investigated by using UV–vis spectroscopy techniques. Transmitted light intensities from the gel samples with different agarose concentrations were monitored during the heating (gel-sol) and cooling (sol–gel) processes. It was observed that the transition temperatures, Tm, defined as the location of the maximum of the first derivative of the sigmoidal transition paths obtained from the UV–vis technique, slightly increased by increasing the agarose concentration in both the HMP and LMP samples. Here, we express the phase transitions of the agar-water system, as a representative of reversible physical gels, in terms of a modified Susceptible-Infected-Susceptible epidemic model whose solutions are the well-known 5-point sigmoidal curves. The gel point is hard to determine experimentally and various computational techniques are used for its characterization. Based on previous work, we locate the gel p...
TL;DR: Hybrid modified microcrystalline cellulose (HMCC) with SiO2 nanoparticles being in-situ loaded on the surface of micro-cellulose (MCC) was obtained through a sol-gel process as mentioned in this paper.
Abstract: Hybrid modified microcrystalline cellulose (HMCC), with SiO2 nanoparticles being in-situ loaded on the surface of microcrystalline cellulose (MCC), was obtained through a sol-gel process of...
TL;DR: In this article, the blends of polyethylene terephthalate (PET)/ethylene propylene diene rubber (EPDM) in the presence of multi-walled carbon nanotubes (MWCNT) were prepared by melt com...
Abstract: In this study the blends of polyethylene terephthalate (PET)/ethylene propylene diene rubber (EPDM) in the presence of multi-walled carbon nanotubes (MWCNT) (1 and 3 wt %) were prepared by melt com...
TL;DR: A sample of propargyl dehydroabietic ester grafted to α-azide substituted poly(ϵ-caprolactone) (PCL-g-DAPE) in THF was characterized at 24°C, 30°C and 40°C by a combination of on-line measuremen.
Abstract: A sample of propargyl dehydroabietic ester grafted to α-azide substituted poly(ϵ-caprolactone) (PCL-g-DAPE) in THF was characterized at 24°C, 30°C, 40°C, 50°C by a combination of on-line measuremen...
TL;DR: The rheological behaviors of polypropylene (PP)/poly(1-butene) (PB) blends with homo-polypropylene(PP1) or impact polypropylon (PP2), a poly(propylene-co-ethylene) as the PP component were studie...
Abstract: The rheological behaviors of polypropylene (PP)/poly(1-butene) (PB) blends with homo-polypropylene (PP1) or impact polypropylene (PP2), a poly(propylene-co-ethylene) as the PP component were studie...
TL;DR: Citrate-based bioelastomers have great potentials in various biomedical fields and an appropriate selection of diol monomers could tune their properties to fulfill different application requirements as discussed by the authors.
Abstract: Citrate-based bioelastomers have great potentials in various biomedical fields. An appropriate selection of diol monomers could tune their properties to fulfill different application requirements. ...
TL;DR: In this paper, the relationship between the initiators and the properties of grafted polypropylene (PP) is discussed and guidance for designing polymers with different performance through selecting appr...
Abstract: To understand the relationship between the initiators and the properties of grafted polypropylene (PP), and provide guidance for designing polymers with different performance through selecting appr...
TL;DR: Nano-Sb2O3 particles and brominated epoxy resin (BEO) powders were dispersed in poly (butylene terephthalate) (PBT) by high energy ball milling (HEBM) as mentioned in this paper.
Abstract: Nano-Sb2O3 particles and brominated epoxy resin (BEO) powders were dispersed in poly (butylene terephthalate) (PBT) by high energy ball milling (HEBM). Then the nanocomposites were prepared by a tw...
TL;DR: A novel flame retardant (NSiB) containing nitrogen, silicon and boron was synthesized through reacting of N-(β-aminoethyl)-γ-aminopropyl trimethoxy-silane (KH-792) and boric acid as discussed by the authors.
Abstract: A novel flame retardant (NSiB) containing nitrogen, silicon and boron was synthesized through reacting of N-(β-aminoethyl)-γ-aminopropyl trimethoxy-silane (KH-792) and boric acid. The structure of ...
TL;DR: Binary composites of poly(lactic acid) (PLA)/calcium carbonate whiskers (CCW) with different weight fractions were prepared with a vane mixer based on extensional rheology as discussed by the authors.
Abstract: Binary composites of poly(lactic acid) (PLA)/calcium carbonate whiskers (CCW) with different weight fractions were prepared with a vane mixer based on extensional rheology. The mechanical propertie...
TL;DR: In this article, the preparation and dielectric properties of silver-polydopamine/poly(vinylidene fluoride) (Ag-PDOP/PVDF) composite films with suppressed die-lectric loss are reported.
Abstract: The preparation and dielectric properties of silver-polydopamine/poly(vinylidene fluoride) (Ag-PDOP/PVDF) composite films with suppressed dielectric loss are reported. The dielectric loss tangents ...
TL;DR: In this paper, polyurethane foams with various isocyanate/polyol ratios, reinforced with various amounts of nanosized TiO2, were prepared and their morphological properties were investigated.
Abstract: Polyurethane foams with various isocyanate/polyol ratios, reinforced with various amounts of nanosized TiO2, were prepared and their morphological properties were investigated. The nanoparticles we...
TL;DR: In this paper, carbon nano-tube (CNT) and carbon fiber (CF)-filled polyolefin nano-composites were prepared by melt blending and the water absorption, expansion ratio, electrical conductivities, and physical and mechanical properties of the prepared nano composites were extensively investigated.
Abstract: Carbon nano-tube (CNT)- and carbon fiber (CF)-filled polyolefin nano-composites were prepared by melt blending. The water absorption, expansion ratio, electrical conductivities, and physical and mechanical properties of the prepared nano-composites were extensively investigated. The experimental results showed that the water absorption increased with the elapsed time from the starting point when the samples were immersed into the water. The linear expansion ratios of the composites were found to increase gradually with time till reaching an equilibrium value. Composites with excellent dielectric properties could be obtained when the filler content was above the percolation threshold. The addition of CNT and CF resulted in no obvious improvement in mechanical properties in the present study, but both Shore hardness and Vicat softening temperature (VST) of the composites increased with increasing filler content. The present work will be of practical importance to the CNT/CF filler composites design,...
TL;DR: In this paper, the authors account for the increase in the energy of activation of viscous flow of polymers by an amount proportional to the force of entropic elasticity of the stretched macromolecules.
Abstract: Accounting for the increase in the energy of activation of viscous flow of polymers by an amount proportional to the force of entropic elasticity of the stretched macromolecules, allows for...