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Polymers, Volume 10, Issue 10 (October 2018)

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Cover Story (view full-size image) The photosensitive sodium copper chlorophyllin (SCC) was incorporated into thermo-responsive [...] Read more.
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Open AccessArticle Hydrothermal Synthesis of Cellulose Nanocrystal-Grafted-Acrylic Acid Aerogels with Superabsorbent Properties
Polymers 2018, 10(10), 1168; https://doi.org/10.3390/polym10101168
Received: 12 September 2018 / Revised: 15 October 2018 / Accepted: 17 October 2018 / Published: 19 October 2018
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Abstract
In this work, we applied a fast and simple method to synthesize cellulose nanocrystal (CNC) aerogels, via a hydrothermal strategy followed by freeze drying. The characteristics and morphology of the obtained CNC-g-AA aerogels were affected by the hydrothermal treatment time, volume of added
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In this work, we applied a fast and simple method to synthesize cellulose nanocrystal (CNC) aerogels, via a hydrothermal strategy followed by freeze drying. The characteristics and morphology of the obtained CNC-g-AA aerogels were affected by the hydrothermal treatment time, volume of added AA (acrylic acid), and the mass fraction of the CNCs. The formation mechanism of the aerogels involved free radical graft copolymerization of AA and CNCs with the cross-linker N,N′-methylene bis(acrylamide) (MBA) during the hydrothermal process. The swelling ratio of the CNC-g-AA aerogels was as high as 495:1, which is considerably greater than that of other polysaccharide-g-AA aerogels systems. Moreover, the CNC-g-AA aerogels exhibited an excellent methyl blue (MB) adsorption capacity and the ability to undergo rapid desorption/regeneration. The maximum adsorption capacity of the CNC-g-AA aerogels for MB was greater than 400 mg/g. Excellent regeneration performance further indicates the promise of our CNC-g-AA aerogels as an adsorbent for applications in environmental remediation. Full article
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Open AccessArticle Mass-Production and Characterizations of Polyvinyl Alcohol/Sodium Alginate/Graphene Porous Nanofiber Membranes Using Needleless Dynamic Linear Electrospinning
Polymers 2018, 10(10), 1167; https://doi.org/10.3390/polym10101167
Received: 14 August 2018 / Revised: 11 October 2018 / Accepted: 13 October 2018 / Published: 19 October 2018
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Abstract
The aim of this study was to investigate the feasibility of large-scale preparation of porous polyvinyl alcohol/sodium alginate/graphene (Gr) (Gr-AP) nanofiber membranes using a copper wire needleless dynamic linear electrode electrospinning machine. Furthermore, the effects of Gr concentrations (0, 0.0375, 0.075, 0.25, 0.5,
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The aim of this study was to investigate the feasibility of large-scale preparation of porous polyvinyl alcohol/sodium alginate/graphene (Gr) (Gr-AP) nanofiber membranes using a copper wire needleless dynamic linear electrode electrospinning machine. Furthermore, the effects of Gr concentrations (0, 0.0375, 0.075, 0.25, 0.5, and 0.75 wt.%) on the morphology, electrical, hydrophilicity and thermal properties were evaluated. Results indicate that the dynamic linear electrospun Gr-AP membranes have a high yield of 1.25 g/h and are composed of porous finer nanofibers with a diameter of 141 ± 31 nm. Gr improved the morphology, homogeneity, hydrophobicity and thermal stability of Gr-AP nanofiber membranes. The critical conductive threshold is 0.075 wt.% for Gr, which provides the nanofiber membranes with an even distribution of diameter, an optimal conductivity, good hydrophilicity, appropriate specific surface area and optimal thermal stability. Therefore, needleless dynamic linear electrospinning is beneficial to produce high quality Gr-AP porous nanofiber membranes, and the optimal parameters can be used in artificial nerve conduits and serve as a valuable reference for mass production of nanofiber membranes. Full article
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Open AccessArticle Fire Phenomena of Rigid Polyurethane Foams
Polymers 2018, 10(10), 1166; https://doi.org/10.3390/polym10101166
Received: 28 September 2018 / Revised: 16 October 2018 / Accepted: 18 October 2018 / Published: 19 October 2018
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Abstract
Rigid polyurethane foams (RPUFs) typically exhibit low thermal inertia, resulting in short ignition times and rapid flame spread. In this study, the fire phenomena of RPUFs were investigated using a multi-methodological approach to gain detailed insight into the fire behaviour of pentane- and
[...] Read more.
Rigid polyurethane foams (RPUFs) typically exhibit low thermal inertia, resulting in short ignition times and rapid flame spread. In this study, the fire phenomena of RPUFs were investigated using a multi-methodological approach to gain detailed insight into the fire behaviour of pentane- and water-blown polyurethane (PUR) as well as pentane-blown polyisocyanurate polyurethane (PIR) foams with densities ranging from 30 to 100 kg/m3. Thermophysical properties were studied using thermogravimetry (TG); flammability and fire behaviour were investigated by means of the limiting oxygen index (LOI) and a cone calorimeter. Temperature development in burning cone calorimeter specimens was monitored with thermocouples inside the foam samples and visual investigation of quenched specimens’ cross sections gave insight into the morphological changes during burning. A comprehensive investigation is presented, illuminating the processes taking place during foam combustion. Cone calorimeter tests revealed that in-depth absorption of radiation is a significant factor in estimating the time to ignition. Cross sections examined with an electron scanning microscope (SEM) revealed a pyrolysis front with an intact foam structure underneath, and temperature measurement inside burning specimens indicated that, as foam density increased, their burning behaviour shifted towards that of solid materials. The superior fire performance of PIR foams was found to be based on the cellular structure, which is retained in the residue to some extent. Full article
(This article belongs to the Special Issue Flame Retardancy of Polymeric Materials)
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Open AccessArticle Anionic Polymer Brushes for Biomimetic Calcium Phosphate Mineralization—A Surface with Application Potential in Biomaterials
Polymers 2018, 10(10), 1165; https://doi.org/10.3390/polym10101165
Received: 28 August 2018 / Revised: 1 October 2018 / Accepted: 7 October 2018 / Published: 18 October 2018
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Abstract
This article describes the synthesis of anionic polymer brushes and their mineralization with calcium phosphate. The brushes are based on poly(3-sulfopropyl methacrylate potassium salt) providing a highly charged polymer brush surface. Homogeneous brushes with reproducible thicknesses are obtained via surface-initiated atom transfer radical
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This article describes the synthesis of anionic polymer brushes and their mineralization with calcium phosphate. The brushes are based on poly(3-sulfopropyl methacrylate potassium salt) providing a highly charged polymer brush surface. Homogeneous brushes with reproducible thicknesses are obtained via surface-initiated atom transfer radical polymerization. Mineralization with doubly concentrated simulated body fluid yields polymer/inorganic hybrid films containing AB-Type carbonated hydroxyapatite (CHAP), a material resembling the inorganic component of bone. Moreover, growth experiments using Dictyostelium discoideum amoebae demonstrate that the mineral-free and the mineral-containing polymer brushes have a good biocompatibility suggesting their use as biocompatible surfaces in implantology or related fields. Full article
(This article belongs to the Special Issue Hybrid Adhesive and Coatings for Medical Applications)
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Open AccessArticle Preparation of Microparticles Capable of Glucose-Induced Insulin Release under Physiological Conditions
Polymers 2018, 10(10), 1164; https://doi.org/10.3390/polym10101164
Received: 25 September 2018 / Revised: 17 October 2018 / Accepted: 17 October 2018 / Published: 18 October 2018
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Abstract
Hydrogen peroxide (H2O2)-sensitive layer-by-layer films were prepared based on combining phenyl boronic acid (PBA)-modified poly(allylamine) (PAH) with shikimic acid (SA)-modified-PAH through boronate ester bonds. These PBA-PAH/SA-PAH multilayer films could be prepared in aqueous solutions at pH 7.4 and 9.0
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Hydrogen peroxide (H2O2)-sensitive layer-by-layer films were prepared based on combining phenyl boronic acid (PBA)-modified poly(allylamine) (PAH) with shikimic acid (SA)-modified-PAH through boronate ester bonds. These PBA-PAH/SA-PAH multilayer films could be prepared in aqueous solutions at pH 7.4 and 9.0 in the presence of NaCl. It is believed that the electrostatic repulsion between the SA-PAH and PBA-PAH was diminished and the formation of ester bonds between the SA and PBA was promoted in the presence of NaCl. These films readily decomposed in the presence of H2O2 because the boronate ester bonds were cleaved by an oxidation reaction. In addition, SA-PAH/PBA-PAH multilayer films combined with glucose oxidase (GOx) were decomposed in the presence of glucose because GOx catalyzes the oxidation of D-glucose to generate H2O2. The surfaces of CaCO3 microparticles were coated with PAH/GOx/(SA-PAH/PBA-PAH)5 films that absorbed insulin. A 1 mg quantity of these particles released up to 10 μg insulin in the presence 10 mM glucose under physiological conditions. Full article
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Open AccessArticle Preparation and Characterization of Hot Melt Copolyester (PBTI) Ultrafine Particles and Their Effect on the Anti-Pilling Performance of Polyester/Cotton Fabrics
Polymers 2018, 10(10), 1163; https://doi.org/10.3390/polym10101163
Received: 7 September 2018 / Revised: 4 October 2018 / Accepted: 16 October 2018 / Published: 18 October 2018
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Abstract
An ultrafine particle aqueous-phase system of hot melt copolyester was prepared by an inverse emulsion–precipitation method. Laser particle size analysis showed that the diameter of the obtained copolyester particles was mostly distributed between 20 and 100 nm. The structure of the copolymer was
[...] Read more.
An ultrafine particle aqueous-phase system of hot melt copolyester was prepared by an inverse emulsion–precipitation method. Laser particle size analysis showed that the diameter of the obtained copolyester particles was mostly distributed between 20 and 100 nm. The structure of the copolymer was characterized by FT–IR and 1H-NMR, and the melting point of the particles was determined to be 125 °C, as measured by differential scanning calorimetry (DSC). Intrinsic viscosity analysis showed that the particle intrinsic viscosity decreased by 6.73% compared with that of the original copolyester. Polyester/cotton woven fabrics were padded with the ultrafine copolyester particles at different concentrations, and the corresponding SEM showed that the fibers were well bonded to each other. The pilling test results showed that these ultrafine copolyester granules improved the pilling performance of the polyester/cotton woven fabrics to a grade of 4.5–5. Full article
(This article belongs to the Special Issue Polymer Processing for Enhancing Textile Application)
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Open AccessArticle Lignin Phenol Formaldehyde Resoles Using Base-Catalysed Depolymerized Kraft Lignin
Polymers 2018, 10(10), 1162; https://doi.org/10.3390/polym10101162
Received: 28 September 2018 / Revised: 12 October 2018 / Accepted: 15 October 2018 / Published: 17 October 2018
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Abstract
Lignin phenol formaldehyde (LPF) resols were produced using depolymerized lignin fractions at various levels of phenol substitution (50 to 70 wt %). To produce monomeric-rich (BCD-oil) and oligomeric (BCD-oligomers) bio-based phenolic compounds, softwood kraft lignin was base-catalysed degraded. These base-catalysed depolymerized (BCD) building
[...] Read more.
Lignin phenol formaldehyde (LPF) resols were produced using depolymerized lignin fractions at various levels of phenol substitution (50 to 70 wt %). To produce monomeric-rich (BCD-oil) and oligomeric (BCD-oligomers) bio-based phenolic compounds, softwood kraft lignin was base-catalysed degraded. These base-catalysed depolymerized (BCD) building blocks were further used to substitute phenol in the synthesis of phenolic resins and were characterized in detail (such as viscosity, free formaldehyde and phenol content, chemical composition, curing and bonding behaviour). The adhesive properties were compared to a phenol formaldehyde (PF) reference resin and a LPF with untreated kraft lignin. The resins synthesized with the two depolymerized lignin types differ significantly from each other with increasing phenol substitution. While with LPF-BCD-oligomers the viscosity increases and the bonding strength is not effected by increasing lignin content in the resin, a reduction of these properties could be observed with LPF-BCD-oil. Furthermore, LPF-BCD-oil showed similar curing behaviour and ultimate strength as the reference LPF. Adhesive bonds made using LPF-BCD-oligomers exhibited similar strength to those made using PF. Compared to the reference resins, it has been demonstrated that modified renewable lignin based phenolic components can be an equally performing alternative to phenol even for high degrees of substitution of 70%. Full article
(This article belongs to the Special Issue Bio-Based Resins and Crosslinked Polymers from Renewable Resources)
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Open AccessCommunication Selective Polymer Distributed Bragg Reflector Vapor Sensors
Polymers 2018, 10(10), 1161; https://doi.org/10.3390/polym10101161
Received: 6 September 2018 / Revised: 10 October 2018 / Accepted: 14 October 2018 / Published: 17 October 2018
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Abstract
We report on Flory–Huggins photonic sensors for the selective detection of volatile organic compounds without the use of any chemical functionalization. For this purpose, we employed periodic multilayers made of inert cellulose acetate alternated to active polystyrene films whose free volume was modified
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We report on Flory–Huggins photonic sensors for the selective detection of volatile organic compounds without the use of any chemical functionalization. For this purpose, we employed periodic multilayers made of inert cellulose acetate alternated to active polystyrene films whose free volume was modified with silanized ZnO nanoparticles. The simple UV-visible (UV-vis) dynamic optical response of such polymer distributed Bragg reflectors during exposure to vapors of benzene, toluene, o-dichlorobenzene, and carbon tetrachloride allows their detection and recognition based on different chemico–physical affinity with the active polymer medium. Full article
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Open AccessArticle Effects of Nano-CaCO3 Content on the Crystallization, Mechanical Properties, and Cell Structure of PP Nanocomposites in Microcellular Injection Molding
Polymers 2018, 10(10), 1160; https://doi.org/10.3390/polym10101160
Received: 12 September 2018 / Revised: 7 October 2018 / Accepted: 15 October 2018 / Published: 17 October 2018
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Abstract
Using supercritical carbon dioxide as the physical foaming agent, microcellular polypropylene (PP) nanocomposites were prepared in microcellular injection molding. The main purpose of this work is to study effects of content of nano-CaCO3 on the crystallization, mechanical properties, and cell structure of
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Using supercritical carbon dioxide as the physical foaming agent, microcellular polypropylene (PP) nanocomposites were prepared in microcellular injection molding. The main purpose of this work is to study effects of content of nano-CaCO3 on the crystallization, mechanical properties, and cell structure of PP nanocomposites in microcellular injection molding. The results show that adding nano-CaCO3 to PP could improve its mechanical properties and cell structure. The thermal stability and crystallinity enhances with increase of nano-CaCO3. As a bubble nucleating agent, adding nano-CaCO3 to PP improves the cell structure in both the parallel sections and vertical sections. The mechanical properties increase first and then decrease with increase of nano-CaCO3. The mechanical properties are affected by the cell structure, as well. The mechanical properties and cell structure are optimum when the content of nano-CaCO3 is 6 wt %. Full article
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Open AccessArticle Soy Protein-Based Composite Hydrogels: Physico-Chemical Characterization and In Vitro Cytocompatibility
Polymers 2018, 10(10), 1159; https://doi.org/10.3390/polym10101159
Received: 24 July 2018 / Revised: 10 October 2018 / Accepted: 12 October 2018 / Published: 17 October 2018
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Abstract
Novel composite hydrogels based on the combination of alginate (Alg), soy protein isolate (SPI) and bioactive glass (BG) nanoparticles were developed for soft tissue engineering. Human umbilical vein endothelial cells (HUVEC) and normal human dermal fibroblasts were cultivated on hydrogels for 7, 14
[...] Read more.
Novel composite hydrogels based on the combination of alginate (Alg), soy protein isolate (SPI) and bioactive glass (BG) nanoparticles were developed for soft tissue engineering. Human umbilical vein endothelial cells (HUVEC) and normal human dermal fibroblasts were cultivated on hydrogels for 7, 14 and 21 days. Cell morphology was visualized using fluorescent staining at Days 7 and 14 for fibroblast cells and Days 14 and 21 for HUVEC. Metabolic activity of cells was analyzed using a colorimetric assay (water soluble tetrazolium (WST) assay). Compared to pure Alg, Alg/SPI and Alg/SPI/BG provided superior surfaces for both types of cells, supporting their attachment, growth, spreading and metabolic activity. Fibroblasts showed better colonization and growth on Alg/SPI/BG hydrogels compared to Alg/SPI hydrogels. The results indicate that such novel composite hydrogels might find applications in soft tissue regeneration. Full article
(This article belongs to the Special Issue Polymer Scaffolds for Biomedical Application)
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Open AccessArticle Influence of Ethylene Oxide Content in Nonionic Surfactant to the Hydrolysis of Reactive Dye in Silicone Non-Aqueous Dyeing System
Polymers 2018, 10(10), 1158; https://doi.org/10.3390/polym10101158
Received: 18 September 2018 / Revised: 8 October 2018 / Accepted: 14 October 2018 / Published: 17 October 2018
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Abstract
Silicone reverse dyeing technology provides an important means of saving water and salts-free in the textile dyeing industry. The interactions between dyes and surfactants may influence the hydrolysis of dye during dyeing. In this investigation, the effect of ethylene oxide content in nonionic
[...] Read more.
Silicone reverse dyeing technology provides an important means of saving water and salts-free in the textile dyeing industry. The interactions between dyes and surfactants may influence the hydrolysis of dye during dyeing. In this investigation, the effect of ethylene oxide content in nonionic surfactant on the hydrolytic reaction of reactive dye was firstly investigated in a siloxane reverse emulsion dyeing system. Compared with no surfactants, the hydrolytic reaction of vinyl sulfone reactive dye was a slowdown when some nonionic surfactants were used during dyeing. Usually, the hydrophobic groups in nonionic surfactants were dodecyl chains but their polar head groups were different. The hydrolytic reaction of vinyl sulfone dye showed that the longer of EO (ethylene oxide) chains, the faster the hydrolytic reaction of vinyl sulfone dye. From the absorption spectrum of dye, it could be concluded that more of dyes would be solubilized into the formed micelles, and dye-surfactant complexes were adhered to the surface of micelles if the molecular structure of surfactant had a shorter EO chains. Furthermore, the intramolecular or intermolecular hydrogen bond could be formed between dye and surfactant, which would further influence the hydrolytic reaction of vinyl sulfone dye. However, the solubility of surfactant in siloxane non-aqueous media would decrease with the increase of EO chains. Meanwhile, the dispersion of dye was enhanced as well as the hydrolytic reaction of dye. From this investigation, some surfactant can be used to improve the fixation of reactive dye during dyeing. Furthermore, washing times after dyeing and the ecological problems can be decreased. Full article
(This article belongs to the Special Issue Polymer Processing for Enhancing Textile Application)
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Open AccessArticle Effects of Hydrothermal Pretreatment on the Structural Characteristics of Organosolv Lignin from Triarrhena lutarioriparia
Polymers 2018, 10(10), 1157; https://doi.org/10.3390/polym10101157
Received: 28 August 2018 / Revised: 26 September 2018 / Accepted: 14 October 2018 / Published: 16 October 2018
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Abstract
The effects of hydrothermal pretreatment (170–180 °C, 30–60 min) on the structural characteristics of enzymatic and extracted lignin from Triarrhena lutarioriparia (TL) during the integrated delignification process have been comprehensively investigated. Ion chromatography and NMR characterization showed that liquid products after
[...] Read more.
The effects of hydrothermal pretreatment (170–180 °C, 30–60 min) on the structural characteristics of enzymatic and extracted lignin from Triarrhena lutarioriparia (TL) during the integrated delignification process have been comprehensively investigated. Ion chromatography and NMR characterization showed that liquid products after mild hydrothermal process (170 °C, 30 min) were mainly composed of xylooligosaccharide (XOS) with different degrees of polymerization (DP ≥ 2). In addition, the structural changes of lignin during hydrothermal pretreatment and organic acid delignification process have been demonstrated by quantitative 2D heteronuclear single quantum coherence (2D-HSQC) and 31P-NMR techniques. Results showed that the structural changes of lignin (e.g., cleavage of β-O-4 linkages) induced by the hydrothermal pretreatment will facilitate the subsequent organic acid delignification process, and acetylated lignin could be obtained with a considerable yield, which can be used in lignin-based composite and candidate feedstock for catalytic upgrading of lignin. In short, the proposed process facilitates the producing of XOS and acetylated lignin for lignin valorization. Full article
(This article belongs to the Special Issue Lignin Polymers: Structures, Reactions and Applications)
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Open AccessArticle Slip Spring-Based Mesoscopic Simulations of Polymer Networks: Methodology and the Corresponding Computational Code
Polymers 2018, 10(10), 1156; https://doi.org/10.3390/polym10101156
Received: 11 September 2018 / Revised: 10 October 2018 / Accepted: 12 October 2018 / Published: 16 October 2018
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Abstract
In previous work by the authors, a new methodology was developed for Brownian dynamics/kinetic Monte Carlo (BD/kMC) simulations of polymer melts. In this study, this methodology is extended for dynamical simulations of crosslinked polymer networks in a coarse-grained representation, wherein chains are modeled
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In previous work by the authors, a new methodology was developed for Brownian dynamics/kinetic Monte Carlo (BD/kMC) simulations of polymer melts. In this study, this methodology is extended for dynamical simulations of crosslinked polymer networks in a coarse-grained representation, wherein chains are modeled as sequences of beads, each bead encompassing a few Kuhn segments. In addition, the C++ code embodying these simulations, entitled Engine for Mesoscopic Simulations for Polymer Networks (EMSIPON) is described in detail. A crosslinked network of cis-1,4-polyisoprene is chosen as a test system. From the thermodynamic point of view, the system is fully described by a Helmholtz energy consisting of three explicit contributions: entropic springs, slip springs and non-bonded interactions. Entanglements between subchains in the network are represented by slip springs. The ends of the slip springs undergo thermally activated hops between adjacent beads along the chain backbones, which are tracked by kinetic Monte Carlo simulation. In addition, creation/destruction processes are included for the slip springs at dangling subchain ends. The Helmholtz energy of non-bonded interactions is derived from the Sanchez–Lacombe equation of state. The isothermal compressibility of the polymer network is predicted from equilibrium density fluctuations in very good agreement with the underlying equation of state and with experiment. Moreover, the methodology and the corresponding C++ code are applied to simulate elongational deformations of polymer rubbers. The shear stress relaxation modulus is predicted from equilibrium simulations of several microseconds of physical time in the undeformed state, as well as from stress-strain curves of the crosslinked polymer networks under deformation. Full article
(This article belongs to the Special Issue Theory and Simulations of Entangled Polymers)
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Open AccessArticle The Continuum Approach to the Description of Semi-Crystalline Polymers Deformation Regimes: The Role of Dynamic and Translational Defects
Polymers 2018, 10(10), 1155; https://doi.org/10.3390/polym10101155
Received: 24 August 2018 / Revised: 12 October 2018 / Accepted: 13 October 2018 / Published: 16 October 2018
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Abstract
This paper presents a new approach to describe the mechanical behavior of semi-crystalline polymers, the plastic deformation of which is determined by their two-phase structure. To describe the plastic behavior of semi-crystalline polymers, a two-phase model is used. In the framework of this
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This paper presents a new approach to describe the mechanical behavior of semi-crystalline polymers, the plastic deformation of which is determined by their two-phase structure. To describe the plastic behavior of semi-crystalline polymers, a two-phase model is used. In the framework of this model, one phase is in a hard (crystalline) state, and the other in a soft (amorphous) state. The two-phase material is modeled by a single-phase homogeneous continuum based on the approximation of the effective medium. It is assumed that two infinitely close material points of the continuum are connected in series by elastic and viscous bonds, which corresponds to the Maxwell model. It is shown that, in this case, the Maxwell continuum is a pseudo-Euclidean space. Generalizing the definition of defects from a three-dimensional space to a four-dimensional pseudo-Euclidean space, we obtained a dynamic system of nonlinear, interrelated equations to describe the behavior of translational-type defects in the solid phase and dynamic defects in the amorphous phase. As an example of an application for these equations, the phenomenon of creep under uniaxial loading is considered. It is shown that the formalism of the proposed two-phase model makes it possible to describe creep phenomenon regularities, which correspond to both the aging theory and the flow theory. Full article
(This article belongs to the Special Issue Mechanical Behavior of Polymers)
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Open AccessArticle Effects of Calcium Alginate Submicroparticles on Seed Germination and Seedling Growth of Wheat (Triticum aestivum L.)
Polymers 2018, 10(10), 1154; https://doi.org/10.3390/polym10101154
Received: 20 September 2018 / Revised: 5 October 2018 / Accepted: 6 October 2018 / Published: 16 October 2018
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Abstract
Calcium alginate (CaAlg) submicroparticles have a potential application in agricultural delivery systems. This study investigated the effects of CaAlg submicroparticles on seed germination and seedling growth of wheat. CaAlg submicroparticles with a Z-average diameter of around 250.4 nm and a measured zeta potential
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Calcium alginate (CaAlg) submicroparticles have a potential application in agricultural delivery systems. This study investigated the effects of CaAlg submicroparticles on seed germination and seedling growth of wheat. CaAlg submicroparticles with a Z-average diameter of around 250.4 nm and a measured zeta potential value of about −25.4 mV were prepared and characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDS). After this, the effects of the concentration of CaAlg submicroparticles (10–500 μg/mL) on germination percentage, seedling length, the number of adventitious roots, chlorophyll content and soluble protein content were evaluated. The results demonstrated a significant increase in the level of germination percentage (9.0%), seedling index (50.3%), adventitious roots (27.5%), seedling length (17.0%), chlorophyll (8.7%) and soluble protein contents (4.5%) at a concentration of 100 μg/mL. However, an inhibitory effect was observed at a concentration of 500 μg/mL. The SEM examination showed that CaAlg submicroparticles could be successfully adsorbed onto the surface of the wheat seed. Further studies proved that CaAlg submicroparticles at a concentration of 100 μg/mL promoted the expression of indole-3-acetic acid (IAA)-related genes (YUCCA9, AUX1, ARF and UGT) in wheat, which resulted in an increase of 69% and 21% in IAA concentration in wheat roots and shoots, respectively. Full article
(This article belongs to the Special Issue Polysaccharides)
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Open AccessArticle Mechanisms of the Complex Thermo-Mechanical Behavior of Polymer Glass Across a Wide Range of Temperature Variations
Polymers 2018, 10(10), 1153; https://doi.org/10.3390/polym10101153
Received: 26 September 2018 / Revised: 13 October 2018 / Accepted: 15 October 2018 / Published: 16 October 2018
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Abstract
This paper aims to explore the mechanisms of the complex thermo-mechanical behavior of polymer glass across a wide range of temperature variations. To this end, the free vibration frequency spectrum of simply supported poly(methyl methacrylate) (PMMA) beams was thoroughly investigated with the aid
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This paper aims to explore the mechanisms of the complex thermo-mechanical behavior of polymer glass across a wide range of temperature variations. To this end, the free vibration frequency spectrum of simply supported poly(methyl methacrylate) (PMMA) beams was thoroughly investigated with the aid of the impulse excitation technique. It was found that the amplitude ratio of the multiple peaks in the frequency spectrum is a strongly dependent on temperature, and that the peaks correspond to the multiple vibrational modes of the molecular network of PMMA. At a low temperature, the vibration is dominated by the overall microstructure of PMMA. With increasing the temperature, however, the contribution of the sub-microstructures is retarded by β relaxation. Above 80 °C, the vibration is fully dominated by the microstructure after relaxation. The relaxation time at the transition temperature is of the same order of the vibration period, confirming the contribution of β relaxation. These findings provide a precise method for establishing reliable physical-based constitutive models of polymer glass. Full article
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Open AccessArticle Recycled Carbon Fiber-Supported Polyaniline/Manganese Dioxide Prepared via One-Step Electrodeposition for Flexible Supercapacitor Integrated Electrodes
Polymers 2018, 10(10), 1152; https://doi.org/10.3390/polym10101152
Received: 12 September 2018 / Revised: 11 October 2018 / Accepted: 12 October 2018 / Published: 16 October 2018
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Abstract
The exploration of multifunctional electrode materials has been a hotspot for the development of high-performance supercapacitors. We have used carbon fiber plates recovered from construction waste to prepare high-quality flexible carbon fiber materials by pyrolysis of epoxy resin. The as-prepared recycled carbon fiber
[...] Read more.
The exploration of multifunctional electrode materials has been a hotspot for the development of high-performance supercapacitors. We have used carbon fiber plates recovered from construction waste to prepare high-quality flexible carbon fiber materials by pyrolysis of epoxy resin. The as-prepared recycled carbon fiber has a diameter of 8 μm and is the perfect substrate material for flexible electrode materials. Furthermore, polyaniline and manganese dioxide are uniformly deposited on the recycled carbon fiber by one-step electrodeposition to form an active film. The recycled carbon fiber/polyaniline/MnO2 composite shows an excellent specific capacitance of 475.1 F·g−1 and capacitance retention of 86.1% after 5000 GCD cycles at 1 A·g−1 in 1 M Na2SO4 electrolyte. The composites optimized for electrodeposition time have more electroactive sites, faster ions and electron transfer, structural stability and higher conductivity, endowing the composites promising application prospect. Full article
(This article belongs to the Special Issue Polymers for Energy Applications)
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Open AccessArticle Facile Route for Bio-Phenol Siloxane Synthesis via Heterogeneous Catalytic Method and its Autonomic Antibacterial Property
Polymers 2018, 10(10), 1151; https://doi.org/10.3390/polym10101151
Received: 12 September 2018 / Revised: 9 October 2018 / Accepted: 11 October 2018 / Published: 16 October 2018
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Abstract
Eugenol, used as bio-phenol, was designed to replace the hydrogen atom of hydrogenterminated siloxane by hydrosilylation reaction under the presence of alumina-supported platinum catalyst (Pt-Al2O3), silica-supported platinum catalyst (Pt-SiO2) and carbon nanotube-supported platinum catalyst (Pt-CNT), respectively. The
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Eugenol, used as bio-phenol, was designed to replace the hydrogen atom of hydrogenterminated siloxane by hydrosilylation reaction under the presence of alumina-supported platinum catalyst (Pt-Al2O3), silica-supported platinum catalyst (Pt-SiO2) and carbon nanotube-supported platinum catalyst (Pt-CNT), respectively. The catalytic activities of these three platinum catalysts were measured by nuclear magnetic resonance hydrogen spectrometer (1H NMR). The properties of bio-phenol siloxane were characterized by Fourier transform infrared spectrometer (FT–IR), UV-visible spectrophotometer (UV) and thermogravimeter (TGA), and its antibacterial property against Escherichia coli was also studied. The results showed that the catalytic activity of the catalyst Pt-CNT was preferable. When the catalyst concentration was 100 ppm, the reaction temperature was 80 °C and reaction time was 6 h, the reactant conversion rate reached 97%. After modification with bio-phenol, the thermal stability of the obtained bio-phenol siloxane was improved. For bio-phenol siloxane, when the ratio of weight loss reached 98%, the pyrolysis temperature was raised to 663 °C which was 60 °C higher than hydrogenterminated siloxane. Meanwhile, its autonomic antibacterial property against Escherichia coli was improved significantly. Full article
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Open AccessArticle A Phenolphthalein-Dummy Template Molecularly Imprinted Polymer for Highly Selective Extraction and Clean-Up of Bisphenol A in Complex Biological, Environmental and Food Samples
Polymers 2018, 10(10), 1150; https://doi.org/10.3390/polym10101150
Received: 13 September 2018 / Revised: 5 October 2018 / Accepted: 12 October 2018 / Published: 15 October 2018
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Abstract
A molecularly imprinted polymer (MIP) for highly selective solid-phase extraction (SPE) of bisphenol A (BPA) was prepared using phenolphthalein (PP) as the novel dummy template by bulk polymerization. A particle diameter distribution of 40–60 μm, a specific surface area of 359.8 m2
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A molecularly imprinted polymer (MIP) for highly selective solid-phase extraction (SPE) of bisphenol A (BPA) was prepared using phenolphthalein (PP) as the novel dummy template by bulk polymerization. A particle diameter distribution of 40–60 μm, a specific surface area of 359.8 m2·g−1, and a total pore volume of 0.730 cm3·g−1 for the prepared PP-imprinted polymer (PPMIP) were obtained. Good selectivity and specific adsorption capacity for BPA of the prepared PPMIP were also demonstrated by the chromatographic evaluation and sorption experiments. The PPMIP as a SPE sorbent was evaluated for the selective extraction and clean-up of BPA from complex biological, environmental, and food samples. Meanwhile, an accurate and sensitive analytical method based on the PPMIP-SPE purification procedure coupled with high performance liquid chromatography-diode array detector (HPLC-DAD) detection has been successfully developed for the rapid determination of BPA from these samples, with detection limits of 1.3 ng·mL−1 for bovine serum and milk, 2.6 ng·mL−1 for human urine and edible oil, 5.2 ng·mL−1 for soybean sauce, and 1.3 ng·g−1 for sediment. The BPA recoveries at two different spiking levels were in the range of 82.1–106.9%, with relative standard deviation (RSD) values below 7.7%. Full article
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Open AccessArticle Novel Kinetic Models of Xylan Dissolution and Degradation during Ethanol Based Auto-Catalyzed Organosolv Pretreatment of Bamboo
Polymers 2018, 10(10), 1149; https://doi.org/10.3390/polym10101149
Received: 25 September 2018 / Revised: 8 October 2018 / Accepted: 12 October 2018 / Published: 15 October 2018
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Abstract
Due to the invalidity of traditional models, pretreatment conditions dependent parameter of susceptible dissolution degree of xylan (dX) was introduced into the kinetic models. After the introduction of dX, the dissolution of xylan, and the formation of xylo-oligosaccharides and
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Due to the invalidity of traditional models, pretreatment conditions dependent parameter of susceptible dissolution degree of xylan (dX) was introduced into the kinetic models. After the introduction of dX, the dissolution of xylan, and the formation of xylo-oligosaccharides and xylose during ethanol based auto-catalyzed organosolv (EACO) pretreatments of bamboo were well predicted by the pseudo first-order kinetic models (R2 > 97%). The parameter of dX was verified to be a variable dependent of EACO pretreatment conditions (such as solvent content in pretreatment liquor and pretreatment temperature). Based on the established kinetic models of xylan dissolution, the dissolution of glucan and the formation of degradation products (furfural and acetic acid) could also be empirically modeled (R2 > 97%). In addition, the relationship between xylan and lignin removal can provide guidance for alleviating the depositions of lignin or pseudo-lignin. The parameter of dX derived novel kinetic models can not only be used to reveal the multi-step reaction mechanisms of xylan, but also control the final removal of main components in bamboo during EACO pretreatments, indicating scientific and practical significance for governing the biorefinery of woody biomass. Full article
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Open AccessArticle Influence of Biopolymer Carrageenan and Glycerine on the Properties of Extrusion Printed Inks of Carbon Nanotubes
Polymers 2018, 10(10), 1148; https://doi.org/10.3390/polym10101148
Received: 10 September 2018 / Revised: 10 October 2018 / Accepted: 11 October 2018 / Published: 15 October 2018
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Abstract
This article focuses on the preparation of extrusion printing composite inks of multiwall carbon nanotube (MWNT) dispersed separately in iota-carrageenan (IC) and glycerine (G) solution. Both composites (IC-MWNT and G-MWNT) showed shear-thinning behavior when their flow characteristics were tested. Conductive solid tracks/patterns of
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This article focuses on the preparation of extrusion printing composite inks of multiwall carbon nanotube (MWNT) dispersed separately in iota-carrageenan (IC) and glycerine (G) solution. Both composites (IC-MWNT and G-MWNT) showed shear-thinning behavior when their flow characteristics were tested. Conductive solid tracks/patterns of both printed composite inks were deposited on glass slide, PET (polyethylene terephthalate) sheet, and IC gel films substrates. The conductive patterns were characterized with microscopy, scanning electron microscopy (SEM), and profilometer. Moreover, their contact angle and electrical conductivity were measured. Profilometry showed that increased number of extruded layers gave increased cross-sectional area. SEM study showed that printing ink is embedded into the surface of IC film, discontinuous on glass slide and smoother on PET sheet. Conductivity of IC-MWNT track was 9 ± 1 S/m and that of G-MWNT was 2942 ± 84 S/m on glass substrate of one layer thick. This is because fewer carbon nanotubes (CNT) are present in G-MWNT track as confirmed by SEM study. The nature of substrate also affects the conductivity of printed patterns. The impressive result of conductivity of printed patterns of composite inks can make them useful for bioelectronic application. Full article
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Open AccessArticle The Influence of Fiber Cross-Section on Fabric Far-Infrared Properties
Polymers 2018, 10(10), 1147; https://doi.org/10.3390/polym10101147
Received: 13 August 2018 / Revised: 27 September 2018 / Accepted: 12 October 2018 / Published: 14 October 2018
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Abstract
Far-infrared radiation (FIR) possesses various promising properties that are beneficial to an individuals’ health. Exploring the interaction between fiber shapes and FIR performance is thought to be a significant means to develop highly-efficient FIR textile products. In this study, a non-additive triangular polyamide
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Far-infrared radiation (FIR) possesses various promising properties that are beneficial to an individuals’ health. Exploring the interaction between fiber shapes and FIR performance is thought to be a significant means to develop highly-efficient FIR textile products. In this study, a non-additive triangular polyamide (PA) fiber showed excellent FIR properties in both theoretical simulation and experimental verification aspects. The triangular PA fiber affords a higher probability to facilitate large optical path difference, improving both FIR absorption and emission. Textiles woven with the specific triangular PA fiber achieved a remarkable emissivity of 91.85% and temperature difference of 2.11 Celsius, which is obviously superior to the reference circular fiber (86.72%, 1.52 Celsius). Considering the low cost, environmental stability, facile fabrication, as well as being environmentally friendly, this non-additive triangular PA fiber has great potential for high-performance and cost-effective FIR textiles in the future. Full article
(This article belongs to the Special Issue Polymer Processing for Enhancing Textile Application)
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Open AccessReview Intra- and Interpolyelectrolyte Complexes of Polyampholytes
Polymers 2018, 10(10), 1146; https://doi.org/10.3390/polym10101146
Received: 4 September 2018 / Revised: 8 October 2018 / Accepted: 9 October 2018 / Published: 14 October 2018
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Abstract
At present, a large amount of research from experimental and theoretical points of view has been done on interpolyelectrolyte complexes formed by electrostatic attractive forces and/or interpolymer complexes stabilized by hydrogen bonds. By contrast, relatively less attention has been given to polymer–polymer complex
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At present, a large amount of research from experimental and theoretical points of view has been done on interpolyelectrolyte complexes formed by electrostatic attractive forces and/or interpolymer complexes stabilized by hydrogen bonds. By contrast, relatively less attention has been given to polymer–polymer complex formation with synthetic polyampholytes (PA). In this review the complexation of polyampholytes with polyelectrolytes (PE) is considered from theoretical and application points of view. Formation of intra- and interpolyelectrolyte complexes of random, regular, block, dendritic polyampholytes are outlined. A separate subsection is devoted to amphoteric behavior of interpolyelectrolyte complexes. The realization of the so-called “isoelectric effect” for interpolyelectrolyte complexes of water-soluble polyampholytes, amphoteric hydrogels and cryogels with respect to surfactants, dye molecules, polyelectrolytes and proteins is demonstrated. Full article
(This article belongs to the Special Issue Interpolymer Complexes)
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Open AccessArticle Isolation and Characterization of Cellulose Nanocrystals from Rejected Fibers Originated in the Kraft Pulping Process
Polymers 2018, 10(10), 1145; https://doi.org/10.3390/polym10101145
Received: 22 September 2018 / Revised: 9 October 2018 / Accepted: 10 October 2018 / Published: 14 October 2018
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Abstract
In the final process of the bleached kraft pulp there are some cellulose fibers that are separated from the main fibers stream; these fibers are rejected and considered as a low quality fibers, these fibers are known as rejected fiber (RF). In the
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In the final process of the bleached kraft pulp there are some cellulose fibers that are separated from the main fibers stream; these fibers are rejected and considered as a low quality fibers, these fibers are known as rejected fiber (RF). In the present work the potential use of these fibers for Cellulose Nanocrystals (CNCs) synthesis was studied. The physical and chemical properties of synthesized CNCs were characterized through different techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), and Thermogravimetric Analysis (TGA). Results demonstrate the feasibility of CNCs synthesis with a yield of 28.1% and 36.9%, and crystallinity of 73.5% and 82.7%. Finally, the morphology and synthesis conditions suggest that this industrial reject fiber (RF) could be used as a source for the CNCs production, thus adding value to the kraft process and opening new possibilities for innovation in the pulp industry. Full article
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Open AccessArticle Use of Orange Oil Loaded Pectin Films as Antibacterial Material for Food Packaging
Polymers 2018, 10(10), 1144; https://doi.org/10.3390/polym10101144
Received: 24 September 2018 / Revised: 11 October 2018 / Accepted: 11 October 2018 / Published: 14 October 2018
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Abstract
This study aims to develop orange oil loaded in thin mango peel pectin films and evaluate their antibacterial activity against Staphylococcus aureus. The mango peel pectin was obtained from the extraction of ripe Nam Dokmai mango peel by the microwave-assisted method. The thin
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This study aims to develop orange oil loaded in thin mango peel pectin films and evaluate their antibacterial activity against Staphylococcus aureus. The mango peel pectin was obtained from the extraction of ripe Nam Dokmai mango peel by the microwave-assisted method. The thin films were formulated using commercial low methoxy pectin (P) and mango pectin (M) at a ratio of 1:2 with and without glycerol as a plasticizer. Orange oil was loaded into the films at 3% w/w. The orange oil film containing P and M at ratio of 1:2 with 40% w/w of glycerol (P1M2GO) showed the highest percent elongation (12.93 ± 0.89%) and the lowest Young’s modulus values (35.24 ± 3.43 MPa). For limonene loading content, it was found that the amount of limonene after the film drying step was directly related to the final physical structure of the film. Among the various tested films, P1M2GO film had the lowest limonene loading content (59.25 ± 2.09%), which may be because of the presence of numerous micropores in the P1M2GO film’s matrix. The inhibitory effect against the growth of S. aureus was compared in normalized value of clear zone diameter using the normalization value of limonene content in each film. The P1M2GO film showed the highest inhibitory effect against S. aureus with the normalized clear zone of 11.75 mm but no statistically significant difference. This study indicated that the orange oil loaded in mango peel pectin film can be a valuable candidate as antibacterial material for food packaging. Full article
(This article belongs to the Special Issue Antimicrobial Polymer-Based Materials for Food Packaging Applications)
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Open AccessArticle Morphologies Tuning of Polypyrrole and Thermoelectric Properties of Polypyrrole Nanowire/Graphene Composites
Polymers 2018, 10(10), 1143; https://doi.org/10.3390/polym10101143
Received: 11 August 2018 / Revised: 28 September 2018 / Accepted: 29 September 2018 / Published: 13 October 2018
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Abstract
Polypyrrole (PPy) with different morphologies (e.g., particles, nanotubes, and nanowires) were successfully prepared by adding or without adding different kinds of surfactants through a chemical oxidative polymerization method, respectively. The results show that the morphologies of PPy can be effectively controlled and have
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Polypyrrole (PPy) with different morphologies (e.g., particles, nanotubes, and nanowires) were successfully prepared by adding or without adding different kinds of surfactants through a chemical oxidative polymerization method, respectively. The results show that the morphologies of PPy can be effectively controlled and have a significantly effects on their thermoelectric properties. The PPy nanowires exhibit the highest electrical conductivity and Seebeck coefficient among the various PPy morphologies, such as particles, nanotubes, and nanowires, so PPy nanowires were chosen to prepare PPy nanowire/graphene thermoelectric composites via a soft template polymerization method using cetyltrimethyl ammonium bromide as the template. Both electrical conductivity and Seebeck coefficient of the PPy nanowire/graphene composites increased as the content of graphene increases from 0 to 20 wt %, and as the measured temperature increases from 300 K to 380 K, which leds to the same trend for the power factor. A highest power factor of 1.01 μWm−1K−2 at ~380 K was obtained for the PPy nanowire/graphene composites with 20 wt % PPy nanowire, which is about 3.3 times higher than that of the pure PPy nanowire. Full article
(This article belongs to the Special Issue Polymers for Thermoelectric Application)
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Open AccessArticle Enhancement of Plasticizing Effect on Bio-Based Polyurethane Acrylate Solid Polymer Electrolyte and Its Properties
Polymers 2018, 10(10), 1142; https://doi.org/10.3390/polym10101142
Received: 6 September 2018 / Revised: 8 October 2018 / Accepted: 9 October 2018 / Published: 12 October 2018
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Abstract
Polyurethane acrylate (PUA) from vegetable oil has been synthesized and prepared for solid polymer electrolyte. Polyol has been end-capped with Toluene 2,4-Diisocyanate (TDI) followed by hydroxylethylmethylacrylate (HEMA) in a urethanation process to produce PUA. The mixtures were cured to make thin polymeric films
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Polyurethane acrylate (PUA) from vegetable oil has been synthesized and prepared for solid polymer electrolyte. Polyol has been end-capped with Toluene 2,4-Diisocyanate (TDI) followed by hydroxylethylmethylacrylate (HEMA) in a urethanation process to produce PUA. The mixtures were cured to make thin polymeric films under UV radiation to produce excellent cured films which exhibit good thermal stability and obtain high ionic conductivity value. 3 to 15 wt. % of ethylene carbonate (EC) mixed with 25 wt. % LiClO4 was added to PUA to obtain PUA electrolyte systems. PUA modified with plasticizer EC 9 wt. % achieved the highest conductivity of 7.86 × 10−4 S/cm, and relatively improved the linear sweep voltammetry, transference number and dielectric properties. Fourier Transform Infrared Spectroscopy (FTIR) and dielectric analysis were presented. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), followed by X-ray Diffraction (XRD) and morphology have been studied. The addition of plasticizer to the polyurethane acrylate shows significant improvement in terms of the conductivity and performance of the polymer electrolyte. Full article
(This article belongs to the Special Issue Ionic Polymers)
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Open AccessArticle Polymers from Bamboo Extracts Produced by Laccase
Polymers 2018, 10(10), 1141; https://doi.org/10.3390/polym10101141
Received: 13 September 2018 / Revised: 27 September 2018 / Accepted: 9 October 2018 / Published: 12 October 2018
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Abstract
A green methodology for the production of polymers from bamboo powder was investigated. The optimal conditions for the extraction of components from bamboo were defined by incubating the powder in an acetate buffer (pH 5) under boiling for 2 h. Native laccase from
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A green methodology for the production of polymers from bamboo powder was investigated. The optimal conditions for the extraction of components from bamboo were defined by incubating the powder in an acetate buffer (pH 5) under boiling for 2 h. Native laccase from Myceliophthora thermophila was used afterwards to oxidize the extracts from the final resulting extraction liquid. The reduction of the free OH content after enzymatic oxidation, as well as the 1H NMR data, confirmed the efficient polymerization of the extracts. The bamboo powder samples were also subjected to high compression and curing, in the absence and in the presence of laccase, to evaluate the hardness of the tablets formed by enzymatic bonding events. The results revealed a higher hardness when the tablets were produced in the presence of laccase, confirming the role of the catalyst on the precipitation of colloidal lignin and phenolic extractives. Herein we produce new oligomers/polymers by laccase oxidation of the extracts resulting from a clean method boiling. At the same time, the data open up new routes for the exploitation of new lignocellulosic materials by the direct application of the enzyme on the bamboo powder material. Full article
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Open AccessCommunication π-Stacked Polymer Consisting of a Pseudo–meta–[2.2]Paracyclophane Skeleton
Polymers 2018, 10(10), 1140; https://doi.org/10.3390/polym10101140
Received: 27 August 2018 / Revised: 26 September 2018 / Accepted: 2 October 2018 / Published: 12 October 2018
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Abstract
A novel π-stacked polymer based on a pseudo–meta–linked [2.2]paracyclophane moieties was synthesized by Sonogashira-Hagihara coupling. The UV-vis absorption spectra of the synthesized polymer and model compounds revealed an extension of the conjugation length owing to the through-space conjugation. The optical properties
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A novel π-stacked polymer based on a pseudo–meta–linked [2.2]paracyclophane moieties was synthesized by Sonogashira-Hagihara coupling. The UV-vis absorption spectra of the synthesized polymer and model compounds revealed an extension of the conjugation length owing to the through-space conjugation. The optical properties of the π-stacked dimer with the pseudo–meta–linked [2.2]paracyclophane unit were compared with those of the corresponding dimers with the pseudo–ortho– and pseudo–para–linked [2.2]paracyclophane units. Full article
(This article belongs to the Special Issue π-Stacked Polymers)
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Open AccessArticle Thermo-Mechanical Characterisations of Flax Fibre and Thermoplastic Resin Composites during Manufacturing
Polymers 2018, 10(10), 1139; https://doi.org/10.3390/polym10101139
Received: 23 September 2018 / Revised: 4 October 2018 / Accepted: 10 October 2018 / Published: 12 October 2018
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Abstract
The flax fibre reinforced composites with advanced structure, which can be regarded as recyclable parts, are potential and promising materials in the automobile industry. During their manufacturing, the reinforcements or prepregs should be performed to the desired shape beforehand. Mechanical behaviours accordingly play
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The flax fibre reinforced composites with advanced structure, which can be regarded as recyclable parts, are potential and promising materials in the automobile industry. During their manufacturing, the reinforcements or prepregs should be performed to the desired shape beforehand. Mechanical behaviours accordingly play an important role during this process. However, this preforming process is usually under high temperatures, thus, the mechanical behaviours could be modified under this state. Especially for reinforcements produced by flax yarns, has barely been studied. To fill this gap, in this paper the thermos-mechanical characterization of Flax/Polyamide12 (PA12) commingled yarn and prepreg woven fabric is analysed using tensile and in-plane shearing tests under different temperatures and tensile speeds. The results conclusively show that strength can be improved by increasing the temperature below the PA12 melting value on woven fabrics, which is inverse tendency for single yarn. Moreover, increasing tensile speed could increase the strength of the single yarn and fabric. This reveals that the PA12 fluidity has great influence on tensile behaviour. The characterisation results would be employed as prescriptive recommendations in the process of manufacturing flax fibre-reinforced composite parts. Full article
(This article belongs to the Special Issue Polymer Processing for Enhancing Textile Application)
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