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This work exploits the advantage of asymmetric configuration over symmetric supercapacitor in designing high energy density flexible devices from two active electrode materials–keratin‐based renewable‐resource hierarchically porous carbon and hydrous ruthenium oxide (RuO2). The asymmetric device exhibits significantly high capacitance. Conventional estimation of energy storage parameters, however, cannot be applied for devices with a Faradaic energy storage contribution via redox charge transfer mechanism. Therefore, this work applies a precise measurement of pseudocapacitance contribution at various scan rates to correct the device data that reveals effective capacitance of 120 F g−1 with the energy density of 37 W h kg−1 at 776 W kg−1. It also retains excellent rate capability, >74% at high current density 25 A g−1. The charge storage activity and device stability can be further enhanced by introducing redox‐active electrolytes that improve specific capacitance, but the rate capabilities deteriorate at high current densities. Further, the principle of asymmetric electrode design is applied to fabricate a bending‐tolerant, flexible device by depositing active electrode material on wire‐shaped current collector followed by coupling those separated with polyvinyl alcohol gel containing redox electrolyte; it yields 36.8 mF cm−1 specific capacitance at a 0.2 mA cm−1 current density. [ABSTRACT FROM AUTHOR]

In the present study, carbon nanotubes (CNTs) were grown up on nickel‐coated carbon textiles utilizing acetylene gas as a carbon precursor in an isothermal CVD reactor. The effects of CNT coating time (0 to 25 min) in the carbon textile‐phenolic composites (CPCs) prepared via conventional hand‐layup technique followed by compression molding were assessed using microstructures, static and dynamic mechanical thermal analysis, density and electrical properties. Significant improvement was observed in static as well as dynamic mechanical properties and electrical properties for all the CNT coated samples. Though, 15 min coating time gives the optimum results. The results showed ~71, 74, 62, 67, 38, and 45% increment in storage modulus, loss modulus, flexural strength, flexural modulus, tensile strength, Young's modulus, respectively. Furthermore, huge improvement (707%) in electrical conductivity and significant enrichment in thermal stability mark CNTs coated carbon textile as the efficient alternative reinforcement for high‐performance thermo‐structural applications such as aerospace and automotive fields. [ABSTRACT FROM AUTHOR]

It is our great honor to dedicate this special issue of the I Journal of Applied Polymer Science i to Professor Anil K. Bhowmick in celebration of his 65th birthday. THERMOPLASTICS ELASTOMERS, POLYMER BLENDS, AND POLYMER MODIFICATION Thermoplastic elastomers are a class of materials that can be processed at high temperatures such as plastics but show rubbery behavior, like elastomers, at room temperature. Professor Bhowmick's work on compatibilization of rubber-rubber and rubber-plastics blends by phase modification to achieve desired properties is of commercial importance. FAILURE AND DEGRADATION OF POLYMERS Professor Bhowmick's pioneering experimental investigations on understanding the tearing behavior of polymers when the viscoelastic dissipation is minimized provided valuables insights on the mechanisms of reinforcement and adhesion. [Extracted from the article]

Polymer matrix composites reinforced with carbonous fillers are of significant commercial importance thanks to their vast application base. As the performance of such composites largely depends on matrix–filler interaction, the present study is focused on the impact of surface chemical states of polymer matrix and carbonous filler on the viscoelastic performance of the composites. Here we report investigation of the filler–matrix interface through spectroscopic techniques such as X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Viscoelastic properties of various polymer matrix composites prepared by varying the filler volume fraction and/or the matrix/filler type have been studied through dynamic mechanical thermal analysis. Further, to understand the matrix–filler interaction, correlations between viscoelastic parameters and various structural parameters such as the surface area of filler and the surface chemical states of filler/matrix obtained through XPS have been studied. Strong correlations between the viscoelastic parameters and the matrix/filler surface chemical states have been observed, suggesting the XPS as an important tool to study the role of the surface functionalities present on the matrix/filler surface to define the matrix–filler interaction. The filler surface functionalities such as C bound O have been found more compatible with the polymers having aromatic ring in the repeat unit. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48660. [ABSTRACT FROM AUTHOR]

BACKGROUND: Decontamination of water by means of photocatalysis is seen as a sustainable solution. However, catalysts with low recovery from liquid suspension remain the main predicament that obstructs their industrial applications. To overcome this shortcoming, a methodology is reported here for the functionalization of nanospinel nickel zinc ferrite by cystamine ligand to develop Ni0.5Zn0.5Fe2O4@cystamine magnetic recyclable catalyst for water decontamination applications. RESULTS: The diffraction patterns of bare and functionalized nanoferrites indicated that the cubic inverse spinel structure of the particles was not changed after cystamine functionalization. X‐ray photoelectron spectroscopy (XPS) and Raman spectroscopy analyses confirmed the chemical bonding between cystamine and spinel ferrites. The spherical morphology and elemental composition were studied through high‐resolution transmission electron spectroscopy (HRTEM) images and energy‐dispersive X‐ray (EDX) analysis respectively. Deeper understanding of the catalyst's optical behavior and calculation of the energy band gap were achieved by means of photoluminescence spectroscopy. Magnetic saturation values were calculated from vibrating sample magnetometer (VSM) analysis, and almost negligible change was found. A possible photocatalytic mechanism for the removal of organic dye is proposed. CONCLUSION: The present findings imply that the presence of amine groups on the catalyst surface, good dispersibility stability and outstanding catalytic activity make functionalized nanoferrite a suitable candidate for industrial wastewater treatment. Easy synthesis, easy work‐up and short reaction times are some of the advantages of the methodology. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The effects of human hair‐derived porous carbon (HHC) as an eco‐friendly reinforcing filler in the carbon fabric‐reinforced phenolic matrix composites (CPCs) are evaluated through micro‐structural characterization studies, tensile, and flexural tests, dynamic mechanical analysis, density and electrical conductivity measurements. Various interfacial interaction parameters like reinforcement efficiency, C‐factor, adhesion factor, and so on are also calculated and compared for understanding the effects of HHC in composites. Conventional hand‐layup technique is used for impregnation of slurry made of phenolic resin and 0–50 wt% HHC on carbon fabric followed by stacking and curing through hot pressing to get laminates of CPCs. Significant improvement in mechanical, viscoelastic and electrical properties are observed over unfilled composite for all investigated HHC loadings. However, 30–40 wt% filler loading gives the optimum balance of properties. The results show ∼15, 93, 50, 85, and 132% increase in tensile strength, Young's modulus, flexural strength, flexural modulus, and storage modulus, respectively. Moreover drastic gain (1,500%) in electrical conductivity and substantial enhancement in thermal stability of CPCs make HHC as a cheap alternative reinforcing filler for structural composite applications working under thermo‐mechanical loads. POLYM. COMPOS., 40:E1573–E1587, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The presented studies concern the effects of graphite flake (GF) on the properties of a specific and challenging type of composite, that is, phenolic‐carbon fabric (PC) composites. This type of materials are commonly used in large scale, but the studies in this manuscript try to explain in detail the effects of graphite on the characteristics of composites. The results show that Young's modulus exhibits increasing trend however tensile strength and interlaminar shear strength show decrement on increasing the GF content in the PC‐GF composites. Dynamic mechanical thermal analysis (DMTA) reveals that storage modulus (E′) increases by ∼42% and 139% upon addition of 10 and 40 wt% GF in the PC‐GF composites, respectively. Loss modulus (E″) of the composites shows a drastic improvement (∼145%) upon addition of only 10 wt% GF. Moreover, various interfacial interaction parameters such as entanglement density (N), reinforcement efficiency factor (r), C factor (the effectiveness of fillers on the modulus of the composites), interphase adhesion factor (A), and 'b' factor (fiber volume correction factor) of the composites are also evaluated using the data obtained from DMTA and correlated with mechanical properties of the composites. POLYM. ENG. SCI., 58:1987–1998, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The (AgBr) x(LiPO3)(1− x) ( x=0.4 and 0.5) and [(AgI) x(AgBr)0.4− x](Li PO3)0.6 ( x=0.1, 0.2, and 0.3) superionic electrolytes have been prepared by conventional melt quenching using a twin roller. These electrolytes are characterized by X-ray diffraction, SEM, and energy dispersive X-ray analysis (EDAX) for structural investigation. Electrical characterizations have been carried out by the AC impedance analysis. The conductivity of Li PO3 glassy system at room temperature is improved by doping with the silver bromide (AgBr) x(Li PO3)(1− x) and the mixture of silver iodide, silver bromide (AgI-AgBr-Li PO3 system) up to 10−5 and 10−3 Ω−1 cm−1, respectively (improvements by four or five orders of magnitude). The frequency response of ionic conductivity has been analyzed by universal dynamic response model (Jonscher's law) and AC conductivity data are fitted using the Jonscher's power law. The conductivity values obtained by the power law and impedance plots are comparable. The frequency exponent (n) has a value between 0 and 1. The AgI-AgBr-Li PO3 system shows the mixed alkali effect. Summerfield scaling master curve is temperature dependent, which may be due to the contribution of the both lithium and silver ions to ionic conduction. [ABSTRACT FROM AUTHOR]

ABSTRACT This study explores the synergistic effect of aluminium phosphate (ALP) nanoparticles and tungstophosphoric acid (TPA) on the physicochemical properties of sulfonated poly ether ether ketone (SPEEK) nanocomposite membranes. SPEEK/TPA/ALP nanocomposite containing optimum TPA (10 wt %) and varying ALP content (3-10 wt %) are fabricated to investigate the effect of ALP nanoparticles on membrane properties. Experimental results reveal that nanocomposite membrane containing 3 wt % ALP nanoparticles and 10 wt % TPA exhibits 3.3 and 18.8 times higher proton conductivity compared to 10 wt % TPA filled SPEEK composite membrane and reference SPEEK membrane. ALP nanoparticles help in retaining water within the membranes and thus 59.4% reduction in water desorption rate is achieved compared to SPEEK/TPA membrane. The leaching of TPA is reduced by 34.5% which helps in retaining membrane properties. Membranes are thermally stable up to 200°C. Microstructure of the composite films is investigated by scanning electron microscope. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42952. [ABSTRACT FROM AUTHOR]

Exfoliated graphite (EG) was synthesized from natural flake graphite by acid treatment followed by microwave irradiation. A maximum expanded volume of 560 mL/g was achieved for this exfoliation of graphite. EG/phenolic resin composite bipolar plates for polymer electrolyte membrane fuel cell were fabricated with a high loading of EG by compression molding. The composites possess low density, high electrical conductivity, high thermal stability, and high compressive strength. The composite bipolar plates were also characterized by X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and so on. The composite prepared with 50 wt% of EG has shown the desired properties for bipolar plate as per the US Department of Energy (DOE-2015) targets. As a result, the EG-resin composites can be used as bipolar plates for polymer electrolyte membrane fuel cell applications. [ABSTRACT FROM AUTHOR]

The mechanical properties of functionally graded polymeric composites (FGPCs) with varying carbon black loading and the effect of stacking sequence in styrene butadiene rubber (SBR) matrix were studied. For a given average amount of nanofiller, the modulus of FGPCs for any given stacking sequence of layers is higher when compared with its uniformly dispersed polymeric composites (UDPCs) counterpart. Tensile strength, elongation at break, and tear strength either increase or decrease depending on the stacking sequence and average loading of the filler in FGPCs. In addition, the smoother gradation (i.e., lesser difference in the amounts of CB content in adjacent layers) and a wide gap of difference in CB content in a stack has a profound effect on the modulus and tensile strength of FGPCs. Dynamic mechanical analysis shows lesser damping in FGPCs than UDPCs. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Poly(ether ether ketone), PEEK, was functionalized by addition of pendant functional groups, that is, acetyl, carboxylic, acyl chloride, amide, and amine groups in the benzene ring of polymer backbone without substituting the parent (ether or ketonic) functional groups of polymer to improve the mechanical and surface adhesivity with acellular inorganic biomaterials. The functional groups of virgin PEEK and functionalized PEEK were identified by Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance. The crystallinity was studied by X-ray diffraction and further supported by differential scanning calorimetry (DSC) analysis. Similarly, the change in glass transition temperature was confirmed by the DSC and dynamic mechanical analysis (DMA). The improved mechanical property was also evaluated by DMA. The excellent surface adhesivity and bioactivity were revealed by acellular in vitro test using simulated body fluid. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

The article discusses the preparation of functionally graded polymer composites (FGPCs) at various stacking sequences of layers with natural rubber as matrix and carbon black (CB) in graded form where the FGPCs are characterized by hysteresis measurements. The ingredients such as natural rubber, polymerized TQ and zinc oxide were poured along the nip and tensile dumbbell-shaped samples were cut to find out the hysteresis in the specimen. It concludes that for a given average of CB, FPGCs with sequential stacking show higher values of storage modulus.

Deals with a study that determined the effect of holding time on high strain hysteresis loss of carbon black filled rubber vulcanizates. Background information on the study; Experimental procedures; Results and discussion; Conclusions.

Focuses on mathematical technology pertaining to nonlinear large elastic deformation of rubber on the basis of the strain energy density. Name of this theory; Specification of this theory; Methods used in the experiment; Results from the experiment.