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Evaluation of physicochemical properties of film-based alginate for food packing applications e-Polymers (IF 1.675) Pub Date : 2021-01-21 María Azucena Castro-Yobal; Adriana Contreras-Oliva; Veronica Saucedo-Rivalcoba; José Luis Rivera-Armenta; Gabriela Hernández-Ramírez; Josafhat Salinas-Ruiz; Andrés Herrera-Corredor
The indiscriminate use of films as synthetic primary packaging, for the conservation and transport of fruit and vegetable products in postharvest, causes disposal problems. In the present work, films based on sodium alginate were synthesized and characterized, with alginate as a biopolymer matrix, glycerol (plasticizer), oleic acid (control of hydrophilicity), and calcium chloride (cross-linking agent)
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Fabrication of N-halamine polyurethane films with excellent antibacterial properties e-Polymers (IF 1.675) Pub Date : 2021-01-12 Panpan Peng; Jianjun Yang; Qingyun Wu; Mingyuan Wu; Jiuyi Liu; Jianan Zhang
An N-halamine precursor, namely, 2-amino-5-(2-hydroxyethyl)-6-methylpyrimidin-4-one (AHM), was used as a chain extender in the preparation of a series of N-halamine polyurethane (PU) films, in order to also instill antibacterial properties. The mechanical properties, thermodynamic performance, and antimicrobial performance of the functionalized PU films were systematically studied. The results showed
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Sustainable nanocomposite films based on SiO2 and biodegradable poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) for food packaging e-Polymers (IF 1.675) Pub Date : 2021-01-15 Yujuan Qiu; Jirui Fu; Binqing Sun; Xiaojun Ma
Sustainable nanocomposites with transparent, biodegradable, and enhanced mechanical and barrier properties were prepared by the incorporation of SiO2 into poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) films and subsequent solvent casting. The crystallinity of composites could be increased by 67% with appropriate contents of SiO2, which proved that SiO2 were effective nucleating agents for PHBH
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Formulation and optimization of gastroretentive bilayer tablets of calcium carbonate using D-optimal mixture design e-Polymers (IF 1.675) Pub Date : 2021-01-15 Manasa Moganti; Shivakumar H. Nanjappa
Gastroretentive bilayer tablets of calcium carbonate (CC) were developed using D-optimal mixture design. The effect of formulation factors such as levels of HPMC K100 M (X1), sodium bicarbonate (X2), and HPMC E15 LV (X3) on responses like floating lag time (R1) and release of CC at 1 h (R2) and 6 h (R3) was elucidated. The optimized formulations developed by numerical optimization technique were found
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Fabrication and characterization of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite e-Polymers (IF 1.675) Pub Date : 2020-12-23 Xu Yan; Wanru Zhou; Xiaojun Ma; Binqing Sun
In this study, a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite (MMT/PHBH) was fabricated by solution-casting method. The results showed that the addition of MMT increased the crystallinity and the number of spherulites, which indicated that MMT was an effective nucleating agent for PHBH. The maximum decomposition peak of the biocomposites moved to a high
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Synthesis of highly branched water-soluble polyester and its surface sizing agent strengthening mechanism e-Polymers (IF 1.675) Pub Date : 2020-12-23 Wangwang Duan; Xiaorui Li; Yiding Shen; Kai Yang; Hua Zhang
Solvent-free and highly branched water-soluble polyester (WPET) is prepared through self-emulsification methodology, using dimethyl terephthalate (DMT), sodium dimethyl isophthalate-5-sulfonate (SIPM), trimethylolpropane (TMP), and ethylene glycol (EG) by the transesterification and polycondensation. The WPET were first utilized as surface-sizing agents for cellulose fiber paper. The structure, average
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Research on the mechanism of gel accelerator on gel transition of PAN solution by rheology and dynamic light scattering e-Polymers (IF 1.675) Pub Date : 2020-12-05 Zhaoyu Guo; Zhuwei Yao; Feifei Pan; Weiyu Cao
The rheological properties of PAN/DMSO solution and the size and distribution of PAN coils were studied by rheology and dynamic light scattering (DLS) measurements. It was found that water could be used as a gel accelerator and increase the gel transition temperature Tgel and the storage modulus G′ as well as decrease the damping factor tan δ through rheological measurements. DLS test shows that the
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Composite of polylactic acid and microcellulose from kombucha membranes e-Polymers (IF 1.675) Pub Date : 2020-12-08 Bárbara Estefanía Arteaga-Ballesteros; Andrea Guevara-Morales; Eduardo San Martín-Martínez; Ulises Figueroa-López; Horacio Vieyra
Polylactic acid (PLA) is one of the main components of biodegradable and biocompatible composites. Bacterial cellulose from kombucha membranes is an excellent candidate to be used as a natural filler of eco-composites because it is renewable, has low cost, low density, and acceptable specific strength properties, and is biodegradable. The study aimed to prepare composites of PLA and bacterial cellulose
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Gel point determination of gellan biopolymer gel from DC electrical conductivity e-Polymers (IF 1.675) Pub Date : 2020-12-08 Nusrat Jahan; Sakiba Shahnaz; Khandker S. Hossain
Gellan is an anionic bacterial polysaccharide, which in aqueous solution dissociates into a charged gellan polymer molecule containing carboxyl ions and counter ions and forms thermoreversible gel under appropriate conditions. In this study, we investigated the effect of polymer concentration, the concentration of added monovalent metallic ion, and temperature on the DC electrical conductivity of the
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Structural design toward functional materials by electrospinning: A review e-Polymers (IF 1.675) Pub Date : 2020-11-27 Xiuling Yang; Jingwen Wang; Hongtao Guo; Li Liu; Wenhui Xu; Gaigai Duan
Electrospinning as one of the most versatile technologies have attracted a lot of scientists’ interests in past decades due to its great diversity of fabricating nanofibers featuring high aspect ratio, large specific surface area, flexibility, structural abundance, and surface functionality. Remarkable progress has been made in terms of the versatile structures of electrospun fibers and great functionalities
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Preparation and characterization of electrospun fibrous scaffolds of either PVA or PVP for fast release of sildenafil citrate e-Polymers (IF 1.675) Pub Date : 2020-12-03 Erick José Torres-Martínez; Ricardo Vera-Graziano; José Manuel Cervantes-Uc; Nina Bogdanchikova; Amelia Olivas-Sarabia; Ricardo Valdez-Castro; Aracely Serrano-Medina; Ana Leticia Iglesias; Graciela Lizeth Pérez-González; José Manuel Cornejo-Bravo; Luis Jesús Villarreal-Gómez
Sildenafil citrate (SC) has proved to be an effective and inexpensive drug for the treatment of pulmonary arterial hypertension (PAH). This study aims to synthesize electrospun, submicron fiber scaffolds of poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) loaded with SC for fast drug dissolution and its potential use in the treatment of PAH. These fiber scaffolds were prepared through the
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Enhancing tribo-mechanical properties & thermal stability of PA6 by h-BN fillers e-Polymers (IF 1.675) Pub Date : 2020-11-30 Kawaljit Singh Randhawa; Ashwin D. Patel
Mechanical and tribological properties of nylon 6 and nylon 6/h-BN composites were investigated in this paper. Tensile, hardness, and impact tests were carried out for mechanical properties, while wear tests on pin-on-disc were carried out for tribological properties identification. Abrasion resistance tests were carried out on the TABER apparatus to analyze the abrasive wear of materials. SEM, XRD
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Experimental-numerical studies of the effect of cell structure on the mechanical properties of polypropylene foams e-Polymers (IF 1.675) Pub Date : 2020-11-27 Wei Gong; Tuan-Hui Jiang; Xiang-Bu Zeng; Li He; Chun Zhang
The effects of the cell size and distribution on the mechanical properties of polypropylene foam were simulated and analyzed by finite element modeling with ANSYS and supporting experiments. The results show that the reduced cell size and narrow size distribution have beneficial influences on both the tensile and impact strengths. Decreasing the cell size or narrowing the cell size distribution was
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Experimental investigation on the three-dimensional flow field from a meltblowing slot die e-Polymers (IF 1.675) Pub Date : 2020-11-30 Changchun Ji; Yudong Wang
To investigate the distribution characteristics of the three-dimensional flow field under the slot die, an online measurement of the airflow velocity was performed using a hot wire anemometer. The experimental results show that the air-slot end faces have a great influence on the airflow distribution in its vicinity. Compared with the air velocity in the center area, the velocity below the slot end
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Curcumin-loaded polyvinyl butyral film with antibacterial activity e-Polymers (IF 1.675) Pub Date : 2020-11-27 Yanchao Qiao; Lijie Duan
Antibacterial materials have found widespread interest in different fields nowadays. In this study, curcumin (Cur) was incorporated into the polyvinyl butyral (PVB) matrix by dissolving in ethanol for improving the functional properties of a pure PVB film. We found that Cur was uniformly dispersed in the PVB matrix, which showed good compatibility. Moreover, the incorporation of Cur could also improve
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Solubility and diffusion coefficient of supercritical CO2 in polystyrene dynamic melt e-Polymers (IF 1.675) Pub Date : 2020-11-18 Long Wang; Xingyuan Huang; Duyang Wang
The solubility and diffusion coefficient of supercritical CO2 in polystyrene (PS) dynamic melt were studied by using a new constant pressure experimental device. By comparing the experimental results with those of other researchers, the validity of the experimental device and the reliability of the calculated results are verified. The solubility and diffusion coefficient of supercritical CO2 in polystyrene
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Microwave-assisted synthesis of the lipase-catalyzed ring-opening copolymerization of ε-caprolactone and ω-pentadecanolactone: Thermal and FTIR characterization e-Polymers (IF 1.675) Pub Date : 2020-11-13 Wilberth A. Herrera-Kao; Manuel J. Aguilar-Vega; José Manuel Cervantes-Uc
Microwave-assisted synthesis of the lipase-catalyzed ring opening polymerization of ε-caprolactone (ε-CL) and ω-pentadecanolactone (ω-PDL) monomers was studied. A series of P(CL-co-PDL), with different molar feed ratios, including (ε-CL/ω-PDL) 100/0, 75/25, 50/50, 25/75, and 0/100, were synthesized. The resulting polyesters were characterized by Fourier transform infrared spectroscopy (FTIR), differential
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pH-responsive polymer micelles for methotrexate delivery at tumor microenvironments e-Polymers (IF 1.675) Pub Date : 2020-11-16 Teresa Darlen Carrillo-Castillo; Javier Servando Castro-Carmona; Antonia Luna-Velasco; Erasto Armando Zaragoza-Contreras
Methotrexate (MTX) anticancer drug was successfully loaded and released in a controlled manner from polymer micelles made of a diblock copolymer of poly(monomethoxy ethylene glycol)-b-poly(ε-caprolactone) (mPEG-PCL). The empty and MTX-loaded micelles (MTX/mPEG-PCL) were characterized by electron microscopy. The drug release dependence upon pH 5.4, 6.5, and 7.4 for 30 days was proven and characterized
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Redox initiation in semicontinuous polymerization to search for specific mechanical properties of copolymers e-Polymers (IF 1.675) Pub Date : 2020-11-11 José Manuel Sandoval-Díaz; Francisco Javier Rivera-Gálvez; Marta Fernández-García; Carlos Federico Jasso-Gastinel
In this work, for a semicontinuous emulsion polymerization reaction, it is shown that using a redox initiation system at 40°C, substantial modifications in copolymer chain composition with conversion can be easily obtained. To test controllable trajectories for comonomer feeding, linear and parabolic profiles were chosen to get different types of chain composition variations for the 50/50 w/w styrene/n-butyl
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Polar migration behavior of phosphonate groups in phosphonate esterified acrylic grafted epoxy ester composites and their role in substrate protection e-Polymers (IF 1.675) Pub Date : 2020-11-09 Xuyong Chen; Xiaorui Li; Kai Yang; Qian Zhang; Hui Zhu; Kaibin Li
Epoxy resin is widely used in metal surface protection, because of corrosion resistance and adhesion. However, it’s water solubility, oxygen, and water impermeability are not enough. In this paper, linoleic acid (LOFA) and epoxy resin (E20) were used to synthesize epoxy ester (EL) and grafted with phosphonate esterified acrylic resin (AR-P) to prepare acrylic grafted epoxy ester (EL@AR-P). After modification
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Silver-loaded carbon nanofibers for ammonia sensing e-Polymers (IF 1.675) Pub Date : 2020-11-03 Yang Yu; Xin Xin; Shanxiang Zhang; Jinxia Sui; Jing Yu; Xiaoxiong Wang; Yun-Ze Long
Carbon nanofibers (CNFs) were prepared by electrospinning, and silver (Ag) ions were grown on the surface of the CNFs by in situ solution synthesis. The structure and morphology of obtained Ag-doped CNFs (Ag-CNFs) were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The gas sensibility of the composite fiber was investigated by ammonia (NH3) obtained by natural volatilization
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Preparation and characterization of thermoresponsive poly(N-isopropylacrylamide) copolymers with enhanced hydrophilicity e-Polymers (IF 1.675) Pub Date : 2020-10-30 Xiaoguang Fan; Shiya Gu; Liyan Wu; Lei Yang
The poly(N-isopropylacrylamide) copolymers with the enhanced hydrophilicity were synthesized by free radical polymerization from a mixture of the monomers N-isopropylacrylamide (NIPAAm), N-vinyl pyrrolidone (NVP), hydroxypropyl methacrylate (HPM) and 3-trimethoxysilypropyl methacrylate (TMSPM) at different feeding ratios. The attenuated total reflectance-Fourier transform infrared spectrometry (ATR-FTIR)
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Additive manufacturing of PLA-based scaffolds intended for bone regeneration and strategies to improve their biological properties e-Polymers (IF 1.675) Pub Date : 2020-10-23 Ricardo Donate; Mario Monzón; María Elena Alemán-Domínguez
Polylactic acid (PLA) is one of the most commonly used materials in the biomedical sector because of its processability, mechanical properties and biocompatibility. Among the different techniques that are feasible to process this biomaterial, additive manufacturing (AM) has gained attention recently, as it provides the possibility of tuning the design of the structures. This flexibility in the design
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Fabrication of flexible SiO2 nanofibrous yarn via a conjugate electrospinning process e-Polymers (IF 1.675) Pub Date : 2020-10-27 Zhang Dai; Fangfang Yan; Mei Qin; Xu Yan
Nowadays, different kinds of polymers, including ceramics, are electrospun into fibrous materials with different structures by electrospinning. Generally, the as-spun ceramic fibers are randomly oriented membranes and brittle without flexibility. Here, we report the fabrication of flexible SiO2 electrospun yarns using poly(vinyl alcohol) (PVA) as a template through a conjugate electrospinning process
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Synthesis of a phosphoramidate flame retardant and its flame retardancy on cotton fabrics e-Polymers (IF 1.675) Pub Date : 2020-10-21 Huaifang Wang; Yingli Cai; Zhiming Jiang; Shengnan Guo; Ping Zhu
A phosphoramidate flame retardant (dimethyl N,N-bis(2-hydroxyletheyl)phosphoramidate, DMBHP) was synthesized and applied to cotton fabrics for enhancing the flame retardancy. The structure of DMBHP was characterized by FT-IR and NMR. The flame retardancy and combustion behavior of the treated cotton fabrics were evaluated using the vertical flammability test (VFT), limiting oxygen index (LOI), and
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Hydroxyapatite/polyetheretherketone nanocomposites for selective laser sintering: Thermal and mechanical performances e-Polymers (IF 1.675) Pub Date : 2020-09-30 Wenwen Lai; Yan Wang; Hua Fu; Junkun He
In this article, the thermal and mechanical properties of hydroxyapatite (HA)/polyetheretherketone (PEEK) nanocomposites were investigated. The surface of the HA particles was modified by stearic acid. Subsequently, the modified HA and PEEK were ultrasonically dispersed in ethanol and then subjected to drying and ball milling treatments. By controlling the concentration of modified HA, HA/PEEK nanocomposite
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Tribological and nanomechanical properties of a lignin-based biopolymer e-Polymers (IF 1.675) Pub Date : 2020-09-28 Esteban Broitman; Dumitru Nedelcu; Simona-Nicoleta Mazurchevici
A research is reported on the nanomechanics and tribology of the Arboblend V2 Nature biopolymer (a 100% bio-based material, biodegradable, or resistant depending of application), being a mixture of different biopolymers such as lignin, polylactic acid, cellulose, biopolyamides, and other natural additives. The specimens were made by an industrial-scale injection molding machine. The nanoindentation
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Synthesis of high-temperature thermally expandable microcapsules and their effects on foaming quality and surface quality of foamed ABS materials e-Polymers (IF 1.675) Pub Date : 2020-09-28 Wei Gong; Xianglin Pei; Xiaogang Yin; Daming Ban; Hai Fu; Li He
In this paper, acrylonitrile and hydroxypropyl acrylate are used as the binary polymerization monomers, and isooctane is used as the foaming agent to prepare high-temperature thermally expandable microcapsules. Analysis of the effect of blowing agent and crosslinking agent on the expansion properties of high-temperature thermally expandable microcapsules, the effects of foaming agent azodicarbonamide
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Highly thermally conductive boron nitride@UHMWPE composites with segregated structure e-Polymers (IF 1.675) Pub Date : 2020-09-21 Xian Wu; Wei Liu; Li Ren; Chun Zhang
Highly thermally conductive boron nitride (BN)@ultra-high molecular weight polyethylene (UHMWPE) composites with the segregated structure were fabricated by powder mixing and hot pressing. Scanning electron microscopy and polarizing optical microscopy were used to analyze the dispersion of BN particles in the UHMWPE matrix. The morphology observation shows that BN particles are selectively located
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Synthesis, characterization and properties of phthalonitrile-etherified resole resin e-Polymers (IF 1.675) Pub Date : 2020-09-21 Dayong Zhang; Xiaohui Liu; Xuefeng Bai; Yinyin Zhang; Gang Wang; Ying Zhao; Xin Li; Jinhua Zhu; Liping Rong; Changhong Mi
A new type of phthalonitrile-etherified resole resin (PNR) was synthesized from resole resin and 4-nitrophthalonitrile. The differential scanning calorimetry results showed that the curing temperature of PNR is lower than that of phthalonitrile resin. Excellent thermal stability and bonding properties were obtained after curing at 220°C. TGA showed that in air, the temperature of 5% weight loss (T5%)
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Rational synthesis of silicon into polyimide-derived hollow electrospun carbon nanofibers for enhanced lithium storage e-Polymers (IF 1.675) Pub Date : 2020-09-21 Fan Wang; Shouzhi Zhang; Jiawei Zhang; Manshu Han; Guoxiang Pan; Minghua Chen
Flexible energy devices with high energy density and long cycle life are considered to be promising applications in portable electronics. In this study, silicon/carbon nanofiber (Si@CNF) core–shell electrode has been prepared by the coaxial electrospinning method. The precursors of polyimide (PI) were for the first time used to form the core–shell structure of Si@CNF, which depicts outstanding flexibility
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Effect of diacylhydrazine as chain extender on microphase separation and performance of energetic polyurethane elastomer e-Polymers (IF 1.675) Pub Date : 2020-09-02 Yang Gao; Jie Lv; Licheng Liu; Yingfeng Yu
It is low cost and feasible to improve the mechanical properties of polyurethane by using the chain extender with hydrogen bonding function to improve the degree of microphase separation. In this article, hydrazine hydrate was used to react with ethylene carbonate and propylene carbonate, respectively, to synthesize diacylhydrazines as the polyurethane chain extender with amide bonds, which were characterized
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Improved high-temperature damping performance of nitrile-butadiene rubber/phenolic resin composites by introducing different hindered amine molecules e-Polymers (IF 1.675) Pub Date : 2020-09-04 Meng Song; Xiulin Yue; Xiujuan Wang; Mengjie Huang; Mingxing Ma; Wei Pan; Qi Qin
By introducing hindered amine GW-622 or GW-944 into nitrile-butadiene rubber/phenolic resin (NBR/PR, abbreviated as NBPR) matrix, we have prepared different hindered amine/NBR/PR ternary hybrid damping materials with high-temperature damping performance, respectively. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), differential scanning calorimetry (DSC), and dynamic
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Fmoc-diphenylalanine-based hydrogels as a potential carrier for drug delivery e-Polymers (IF 1.675) Pub Date : 2020-08-24 Ranjoo Choe; Seok Il Yun
Self-assembled hydrogels from 9-fluorenylmethoxycarbonyl-modified diphenylalanine (Fmoc-FF) peptides were evaluated as potential vehicles for drug delivery. During self-assembly of Fmoc-FF, high concentrations of indomethacin (IDM) drugs were shown to be incorporated into the hydrogels. The β-sheet arrangement of peptides was found to be predominant in Fmoc-FF–IDM hydrogels regardless of the IDM content
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Mechanical properties and application analysis of spider silk bionic material e-Polymers (IF 1.675) Pub Date : 2020-08-24 Yunqing Gu; Lingzhi Yu; Jiegang Mou; Denghao Wu; Peijian Zhou; Maosen Xu
Spider silk is a kind of natural biomaterial with superior performance. Its mechanical properties and biocompatibility are incomparable with those of other natural and artificial materials. This article first summarizes the structure and the characteristics of natural spider silk. It shows the great research value of spider silk and spider silk bionic materials. Then, the development status of spider
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Sulfonated poly(arylene ether sulfone) functionalized polysilsesquioxane hybrid membranes with enhanced proton conductivity e-Polymers (IF 1.675) Pub Date : 2020-08-13 Rajdeep Mukherjee; Arun Kumar Mandal; Susanta Banerjee
Sulfopropylated polysilsesquioxane and –COOH containing fluorinated sulfonated poly(arylene ether sulfone) composite membranes (SPAES-SS-X) have been prepared via an in situ sol–gel reaction through the solution casting technique. The composite membranes showed excellent thermal and chemical stability, compared to the pristine SPAES membrane. The uniform dispersion of the sulfonated SiOPS nanoparticles
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Synthesis of flexible poly(l-lactide)-b-polyethylene glycol-b-poly(l-lactide) bioplastics by ring-opening polymerization in the presence of chain extender e-Polymers (IF 1.675) Pub Date : 2020-08-03 Yodthong Baimark; Wuttipong Rungseesantivanon; Natcha Prakymoramas
Poly(l-lactide)-b-polyethylene glycol-b-poly(l-lactide) (PLLA-PEG-PLLA) is found to be more flexible than PLLA due to the flexibility of PEG middle blocks. Melt flow and mechanical properties of PLLA-PEG-PLLA were improved through post melt blending with a chain extender (CE). In this work, in situ chain-extended PLLA-PEG-PLLAs were synthesized by ring-opening polymerization in the presence of Joncryl®
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Plugging mechanisms of polymer gel used for hydraulic fracture water shutoff e-Polymers (IF 1.675) Pub Date : 2020-07-27 Song Zhang; Falin Wei; Pingde Liu; Liming Shao; Weitao Li
The performance of polymer gel to plug a hydraulic fracture is greatly affected by its distribution patterns and gelling effect. In this study, the migration of a gel plugging agent in a fracture and its plugging after gelling were investigated by physical simulation experiments. In addition, the distribution patterns of the gel plugging agent and its plugging mechanism after gelling were investigated
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Wetting behaviors of fluoroterpolymer fiber films e-Polymers (IF 1.675) Pub Date : 2020-07-29 Salim Ok; Julia Sheets; Susan Welch; Tingting Liu; Savas Kaya; David R. Cole
Various aspects of electrospun fibers prepared from terpolymer of tetrafluoroethylene (TFE), hexafluoropropylene (HFP), and vinylidene fluoride (VDF) (THV)/acetone solutions at two applied voltages, THV/acetone solutions having Texas montmorillonite with two ratios, and THV/ethyl acetate solutions using two needle sizes are described. Fibers from THV/acetone and THV/ethyl acetate solutions showed shallow
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Synthesis, electropolymerization, and electrochromic performances of two novel tetrathiafulvalene–thiophene assemblies e-Polymers (IF 1.675) Pub Date : 2020-07-20 Yuhao Li; Shixiong Deng; Pengfei Cai; Chenyun Wang; Han Wang; Yongjia Shen
6,7-Bis(hexylthio)-2-[(2-hydroxyethyl)thio]-3-methylthio-tetrathiafulvalene (TTF-2) is coupled with thiophene-3-carboxylic acid and thiophene-3,4-dicarboxylic acid by Steglich esterification, respectively, to afford 2-((4′,5′-bis(hexylthio)-5-(methylthio)-[2,2′-bi(1,3-dithiolylidene)]-4-yl)thio)ethyl thiophene-3-carboxylate (TTF-Th) and bis(2-((4′,5′-bis(hexylthio)-5-(methylthio)-[2,2′-bi(1,3-dith
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Determination of the carbonyl index of polyethylene and polypropylene using specified area under band methodology with ATR-FTIR spectroscopy e-Polymers (IF 1.675) Pub Date : 2020-07-09 Jasmine Almond; Piriya Sugumaar; Margot N. Wenzel; Gavin Hill; Christopher Wallis
The current measurement techniques described in the literature for the determination of the carbonyl index (CI) for polyolefins such as polyethylene and polypropylene were compared and contrasted. These were all found to be inconsistent or inaccurate and were not capable of differentiating significant changes in carbonyl peak evolution throughout accelerated ageing. As a consequence of these findings
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Fabrication of LDPE/PS interpolymer resin particles through a swelling suspension polymerization approach e-Polymers (IF 1.675) Pub Date : 2020-07-06 Nianqing Zhu; Hailong Chen; Xinxing Gao; Rongjie Hou; Zhongbing Ni; Mingqing Chen
A facile method to prepare low-density polyethylene (LDPE)/polystyrene (PS) interpolymer resin particles by swelling suspension polymerization without addition of extra swelling agent was developed. The polymerization temperature, polymerization time, and initiator concentration were investigated. Fourier transform infrared spectroscopy analysis confirmed that the LDPE/PS interpolymer resin particles
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All-optical non-conjugated multi-functionalized photorefractive polymers via ring-opening metathesis polymerization e-Polymers (IF 1.675) Pub Date : 2020-06-26 Haiyan Pei; Yingliang Liu; Dongfang Wang; Jin Wang; Chunjiang Wang; Yanzhao Wu; Wei Pan; Chaohua Su; Meng Song; Shaokui Cao
Non-conjugated multi-functionalized all-optical photorefractive (PR) polymers were designed and synthesized via ring-opening metathesis polymerization (ROMP) of two monomers using Grubbs II catalyst as an initiator. The polymers were characterized by infrared (IR) spectrum, gel permeation chromatography (GPC), UV-visible spectrum (UV-Vis), differential scanning calorimetry (DSC), thermogravimetry (TG)
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Crystal transition and thermal behavior of Nylon 12 e-Polymers (IF 1.675) Pub Date : 2020-06-22 Ning Ma; Wentao Liu; Lili Ma; Suqin He; Hao Liu; Zhenya Zhang; Aihua Sun; Miaoming Huang; Chengshen Zhu
The polyamide 12 (PA12) with different crystal forms is prepared with three crystallization paths. The crystal structures and corresponding thermal properties are systematically investigated. The results reveal that an α-form and a mixed (α + γ)-form of PA12 can be obtained by casting at 30°C and (40–80°C), respectively. Meanwhile, the γ-form of PA12 can be obtained by both casting at 90°C and slow
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The synthesis and characterisation of porous and monodisperse, chemically modified hypercrosslinked poly(acrylonitrile)-based terpolymer as a sorbent for the adsorption of acidic pharmaceuticals e-Polymers (IF 1.675) Pub Date : 2020-06-22 Nur Nida Syamimi Subri; Siti Nurul Ain Md. Jamil; Peter A. G. Cormack; Luqman Chuah Abdullah; Sazlinda Kamaruzaman; Abel A. Adeyi
The synthesis and characterization of porous poly(acrylonitrile(AN)-co-divinylbenzene-80 (DVB-80)-co-vinylbenzylchloride (VBC)) polymers with high specific surface areas and weak anion-exchange character have been successfully researched. The hypercrosslinked (HXL) microspheres were chemically modified with 1,2-ethylenediamine (EDA) to enhance the adsorption selectivity of the HXL materials. The zeta
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Synthesis of aminated polystyrene and its self-assembly with nanoparticles at oil/water interface e-Polymers (IF 1.675) Pub Date : 2020-06-17 Chenliang Shi; Ling Lin; Yukun Yang; Wenjia Luo; Maoqing Deng; Yujie Wu
The influence of density of amino groups, nanoparticles dimension and pH on the interaction between end-functionalized polymers and nanoparticles was extensively investigated in this study. PS–NH2 and H2N–PS–NH2 were prepared using reversible addition–fragmentation chain transfer polymerization and atom transfer radical polymerization. Zero-dimensional carbon dots with sulfonate groups, one-dimensional
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Synthesis of a novel modified chitosan as an intumescent flame retardant for epoxy resin e-Polymers (IF 1.675) Pub Date : 2020-06-16 Haihua Yu; Xiuhang Xu; Yunfei Xia; Mingzhen Pan; Nighat Zarshad; Bo Pang; Anis Ur Rahman; Min Wu; Henmei Ni
According to the concept of fire life cycle assessment (LCA), a new type of intumescent flame retardant was designed and synthesized by chemically bonding chitosan, phosphorus pentoxide and melamine. The resultant compound, chitosan ethoxyl melamine phosphate (CEMP), was characterized by FTIR, 1H NMR, 31P NMR, XRD and SEM. The performance of CEMP and organic montmorillonite (OMMT) was evaluated in
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Tailoring the morphology of poly(high internal phase emulsions) synthesized by using deep eutectic solvents e-Polymers (IF 1.675) Pub Date : 2020-06-16 Silvia T. Huerta-Marcial; Josué D. Mota-Morales
High internal phase emulsions (HIPEs) are among complex biphasic fluids that expand on the traditional emulsion compositions, for instance, for the preparation of macroporous polymers by emulsion templating. The use of deep eutectic solvents (DESs) as the nonaqueous internal phase of HIPEs allows expanding the conditions at which polymerizations are typically carried out in aqueous HIPEs. Herein, the
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Reaction characteristics of polymer expansive jet impact on explosive reactive armour e-Polymers (IF 1.675) Pub Date : 2020-06-09 Jianya Yi; Zhijun Wang; Jianping Yin; Zhimin Zhang
In this study, a new damage mode for the explosive reactive armour (ERA) of a shaped charge jet was proposed. The response characteristics of polytetrafluoroethylene (PTFE) and polyamide (PA) polymer jet impact on the ERA were analysed. The expansion degree and the diameter of the PTFE jet are larger than those of the PA jet, but the compactness of the PTFE jet head is lower than that of the PA jet
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Multilayer-structured fibrous membrane with directional moisture transportability and thermal radiation for high-performance air filtration e-Polymers (IF 1.675) Pub Date : 2020-06-06 Yuyan Yang; Ruidong He; Yixin Cheng; Na Wang
The demand of high-performance filter media for the face masks is urgent nowadays due to the severe air pollution. Herein, a highly breathable and thermal comfort membrane that combines the asymmetrically superwettable skin layer with the nanofibrous membrane has been fabricated via successive electrospinning and electrospraying technologies. Thanks to high porosity, interconnected pore structure,
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Design and preparation of 3D printing intelligent poly N,N-dimethylacrylamide hydrogel actuators e-Polymers (IF 1.675) Pub Date : 2020-06-05 Shengzhu Zhou; Qiang Zhou; Chang Lu; Zhihui Zhang; Luquan Ren
The intelligent poly N,N-dimethylacrylamide hydrogel material system with high mechanical strength and the 3D printable property was prepared via in situ free radical polymerization under vacuum successfully. With the increase in nanofibrillated cellulose (NFC) content, stress and strain of hydrogels increased gradually. As the effective reinforcement, NFC enhanced the crosslinking density, which realized
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Dielectric, mechanical and thermal properties of all-organic PI/PSF composite films by in situ polymerization e-Polymers (IF 1.675) Pub Date : 2020-06-05 Peng Li; Jiajun Yu; Shaohua Jiang; Hong Fang; Kunming Liu; Haoqing Hou
All-organic high dielectric materials are highly required in the field of modern electronic industry and energy storage. In this work, all-organic polyimide/polysulfone composite films with different amounts of PSF (PI/PSF-X) were prepared by in situ polymerization followed by film casting and thermal treatment. The dielectric, mechanical and thermal properties of these PI/PSF-X composite films are
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Preparation and characterization of corn starch/PVA/glycerol composite films incorporated with ε-polylysine as a novel antimicrobial packaging material e-Polymers (IF 1.675) Pub Date : 2020-06-03 Gao Yurong; Li Dapeng
Corn starch/polyvinyl alcohol (PVA)/glycerol composite films incorporated with ε-polylysine were prepared, and their properties were investigated. The Fourier-transform infrared (FTIR) spectroscopy indicated that the interactions happened between the amino group of ε-polylysine and hydroxyl group starch/PVA composite films. X-ray diffraction (XRD) analysis showed that the addition of ε-polylysine decreased
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Pilot-scale production of polylactic acid nanofibers by melt electrospinning e-Polymers (IF 1.675) Pub Date : 2020-06-02 Kylie Koenig; Fabian Langensiepen; Gunnar Seide
Melt electrospinning has been used to manufacture fibers with diameters in the low micrometer range, but the production of submicrometer fibers has proven more challenging. In this study, we investigated the feasibility of fabricating polylactic acid nanofibers using polymer grades with the increasing melt flow rates (15–85 g/10 min at 210°C) by melt electrospinning with a 600-nozzle pilot-scale device
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Silica/polymer core–shell particles prepared via soap-free emulsion polymerization e-Polymers (IF 1.675) Pub Date : 2020-06-02 Mina Ishihara; Tomofumi Kaeda; Takashi Sasaki
In this study, core–shell particles were prepared as a hybrid material, in which a thin polymer shell was formed on the surface of the SiO2 sphere particles. The core–shell structure was successfully achieved without adding a surfactant via simple free-radical polymerization (soap-free emulsion polymerization) for various monomers of styrene, methyl methacrylate (MMA), and their derivatives. MMA formed
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Lipase-catalyzed synthesis and post-polymerization modification of new fully bio-based poly(hexamethylene γ-ketopimelate) and poly(hexamethylene γ-ketopimelate-co-hexamethylene adipate) copolyesters e-Polymers (IF 1.675) Pub Date : 2020-05-29 Wan-Xia Wu
A novel full bio-based ketone-containing aliphatic polyester was prepared by enzyme-catalyzed polycondensation of diethyl γ-ketopimelate (DEK) with 1,6-hexanediol (HDO) using immobilized lipase B from Candida antarctica (CALB). The influences of polymerization conditions such as temperature, time, enzyme amount, and solvent amount on the molecular weight of poly(hexamethylene γ-ketopimelate) (PHK)
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Antibacterial epoxy composites with addition of natural Artemisia annua waste e-Polymers (IF 1.675) Pub Date : 2020-05-27 Chun Wu; Yongsi Yan; Yucheng Wang; Ping Sun; Rongrong Qi
Antibacterial epoxy resins (EP) have great potential in medical and electronic fields. During the process of extracting artemisinin from Artemisia annua, artemisia naphtha (AN) is generated as waste. The components of AN show antibacterial activity, and hence, it is introduced as a novel antibacterial agent in the epoxy matrix. In this study, the properties of epoxy resins with various AN loading were
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Erratum to: Synthesis and characterization of new macromolecule systems for colon-specific drug delivery e-Polymers (IF 1.675) Pub Date : 2020-05-27 M. Galehassadi; M. Mahkam; F. Hosseinzadeh
Journal Name: e-Polymers Volume: 20 Issue: 1 Pages: 272-272
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Morphological transition of amphiphilic block copolymer/PEGylated phospholipid complexes induced by the dynamic subtle balance interactions in the self-assembled aggregates e-Polymers (IF 1.675) Pub Date : 2020-05-27 Susu Tao; Yanyan Chu; Zihao Wang; Xiaoyan Xu; Qinggang Tan
Recently, there has been an increasing interest in the control of morphological transition of block copolymer aggregates. Here, we report how to control the morphological transition of methoxy polyethylene glycol–poly(d,l-lactic acid) (PDLLA–MPEG) by adding 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)] (DSPE–PEG). In the aggregates formed by dialyzing DSPE–PEG/PDLLA–MPEG
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Insight on the effect of a piperonylic acid derivative on the crystallization process, melting behavior, thermal stability, optical and mechanical properties of poly(l-lactic acid) e-Polymers (IF 1.675) Pub Date : 2020-05-03 Li-Sha Zhao; Yan-Hua Cai
A new piperonylic acid derivative (BPASD) was synthesized and evaluated as an organic nucleating agent for poly(l-lactic acid) (PLLA) via melt-crystallization; the other behaviors including cold-crystallization, melting process after crystallization, thermal stability in air atmosphere, and optical and mechanical properties of PLLA/BPASD samples were also investigated. The results of the melt-crystallization
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