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Polyelectrolyte membrane (PEM) with improved proton conductivity and low methanol crossover are highly desirable for direct methanol fuel cells (DMFCs). Herein, the prime goal is to fabricate a ternary hybrid nanocomposite PEM by incorporating low-cost silane functionalized silica nanoparticles (AMPS) nanoparticles into the mixture of Nafion and PVDF-co-HFP, followed by sulfonation with chlorosulfonic acid which has not been reported by any earlier studies. Various physicochemical characterizations including FTIR, TGA, XRD, FESEM-EDS have been performed for the confirmation of formed sulfonated PVDF-co-HFP-AMPS-Nafion (SPAN) membranes. The initial studies including water/methanol uptake, swelling ratios, contact angle and improved ion exchange capacity (0.65 meq. g−1) confirms the hydrophilic and ion exchange properties of the SPAN membranes. The combination of highly hydrophobic partially fluorinated polymer along with hydrophilic AMPS and sulfonic acid moieties have resulted in significant improvement in proton conductivities (1.0 × 10–1 S.cm−1) and optimum methanol permeability values (8.79 × 10–7 cm2s−1) thereby exhibiting a better membrane selectivity value of 1.18 × 105 S.scm−3. Therefore, these unique SPAN membranes have the potentiality to be employed in methanol fuel cells. [ABSTRACT FROM AUTHOR]

The recycled polyolefin waste which included polypropylene (PP) and low‐density polyethylene (LDPE) were collected from hospital and subsequently sterilized by 1% sodium hypochlorite and followed by microwave disinfection. The sterilized BMW were analyzed for growth of pathogens if any. FTIR analysis was performed to analyze the composition of the waste as well as Carbonyl index to evaluate the extent of degradation post sterilization process. Recycled blends were prepared using melt extrusion technique and ethylene diene monomer was added to balance the interface between the varied polyolefin waste. Blends were studied for mechanical and morphological properties. Thermal analysis employed DSC revealed two different peaks of crystallization and melting revealing incompatibility in the blends. DMA showed reduction in the modulus with incorporation of LDPE and EPDM. SEM analysis confirmed the homogeneous distribution of RLD droplets with reduction in the interparticle distance indicates the partial miscibility. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

The study focuses on the synthesis of polyurethane (PU)‐based coating from modified castor oil (CO) via an in situ polymerization process. CO was modified by employing multiple process steps, that included epoxidation, followed by transesterification and acrylation to get the required polyol for PU synthesis. The structural properties were studied using Fourier transform infrared and 1H NMR spectra. Thermogravimetric analysis (TGA) and differential scanning calorimetry revealed an increase in the final degradation temperature and glass transition temperature from 358 and −46.58 °C to 368 and −37.43 °C respectively after transesterification followed by acrylation of epoxidized CO. Hydroxyl value, acid value, amine value and viscosity were observed to change from 208 mg/KOH, 1.75, 13.09 and 428 mPa s to 233 mg/KOH, 1.16, 19.53 and 318 mPa s after transesterification and acrylation of epoxidized CO. Paint formulations at variable OH:NCO ratios like 1:0.9, 1:1 and 1:1.1 were optimized by following the cross‐cut tape test, lap‐shear test, abrasion resistance test and pencil hardness test. Crosslinking density of the paint samples was calculated and the morphological properties of the optimized coating sample were studied using a scanning electron microscope. TGA was carried out to study the thermal properties of the coating. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Incorporation of graphene‐based fillers such as graphene oxide (GO) and reduced graphene oxide (rGO) into polyvinylidene fluoride (PVDF) followed by uniaxial stretching can significantly improve their electroactive phase content as well as the dielectric properties. In this study, the nonisothermal crystallization kinetics of unstretched and uniaxially stretched PVDF‐GO and PVDF‐rGO composite films are investigated through differential scanning calorimetry (DSC) at different cooling rates. Avrami‐modified Jeziorney's model is used to understand their crystallization behavior which leads to the nucleation of electroactive crystalline phases in PVDF. Avrami's exponent "n" values in the range of 2–4 are obtained for nonisothermal crystallization of PVDF in different samples which reveal both two‐ and three‐dimensional growth of spherulites in the crystalline region. Kissinger's method is used to calculate the activation energy of crystallization and the results reveal accelerated crystallization of PVDF after addition of GO and rGO fillers followed by uniaxial stretching. [ABSTRACT FROM AUTHOR]

Carbonaceous nanomaterials and their derivatives have been inspired tremendous enthusiasm in the scientific community. They have been excogitated as the encouraging attributes and the qualified dispersed phase to develop multi‐functional composites. Particularly, graphene and carbon nanotube (anisotropic fillers) have gained substantial research interest owing to their promising characteristics. This highlights an innovative technique to synthesize hybridized nanotube and nanosheet. Initially, parent materials have been synthesized: The pristine CNT has been modified by acid mixture solution, and reduced graphene oxide has been prepared by chemical reduction method. Henceforth, the self‐assembly in situ sol–gel technique has been endorsed here. The synthesized nanohybrids have been characterized by different spectroscopic techniques: FTIR, Raman, UV, and XPS to confirm the attachment of multifunctionalities; meanwhile, the composition and stability have been investigated from XRD and TGA plots. The magnitude of surface charge and particle size distribution have been evaluated for the parent and hybridized products; further, morphology of all the samples has been authenticated from FESEM and TEM. [ABSTRACT FROM AUTHOR]