A detailed study of thermal stability of Poly (Methyl methacrylate)/layered silicate nanocomposites has been carried out in this work. Commercially modified nanoclays such as cloisite 30B (30B), cloisite 93A (C93A) and Na‐MMT and in‐house modified Na‐MMT were used as nanofiller in this study. All the systems were characterized by X‐ray diffraction, thermogravimetric analysis, differential scanning calorimetry, thermal conductivity. Investigations revealed the improved thermal properties of PMMA nanocomposites and the validity of Ozawa and Kissinger for the PMMA nanocomposites were also confirmed. Detailed study on thermal degradation kinetics using Ozawa and Kissinger model was carried out. The flammability of the materials has been investigated by cone calorimeter experiment, which showed reduced flammability of the nanocomposites. Formation of protective char layers during burning of nanocomposites was also observed through SEM analysis.POLYM. COMPOS., 33:2058–2071, 2012. © 2012 Society of Plastics Engineers

Postconsumer Polypropylene and High Impact Polystyrene were obtained from E-waste by mechanical recycling. Recycled PP/HIPS at various blend ratios of 30/70, 50/50 and 70/30 were blended in a batch mixer and was optimized at a blend composition of 70/30 wt ratio of PP/HIPS based on mechanical performance. Mechanical, morphological and thermal properties of optimized recycled blend were studied using triblock copolymer SEBS, as well as SEBS with C20A. Mechanical tests revealed that the blends prepared using 3 wt% of C20A and 5 wt% SEBS with 3% C20A exhibited an increase of 45.13% and 60.73% in impact strength respectively thus indicating interaction of SEBS and C20A with HIPS and PP. Scanning Electron Microscopy (SEM) showed that incorporation of SEBS and C20A reduced average particle size from 5.078 to 2.082 and 1.724 μm respectively. X ray diffraction patterns in the recycled blend nanocomposites showed an increase in the basal spacing indicating the formation of an intercalated structure. Thermal properties of the blend and blend nanocomposites were investigated employing DSC and TGA. Further, DMA analysis showed existence of two distinct T g s corresponding to PP and HIPS thus indicating the formation of a biphase morphology.

The structure of polysodium acrylate (PSA) hydrogel was modified using N,Nmethylenebisacrylamide and cellulose microfibrils (CMFs) as a cross-linker and filler, respectively. CMF was obtained from banana fiber by acid hydrolysis process. The resulting structure and morphology of CMF and PSA/CMF hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD) analysis and scanning electron microscopy. From the FTIR and XRD spectra, the formation of CMF from banana fiber is confirmed. Differential scanning calorimetric study was carried out on the swollen PSA/CMF hydrogels to determine the state and quantification of water present inside the hydrogels. The mechanical characterization of PSA/CMF hydrogels was studied in brief by dynamic mechanical analysis technique.

Hydrogel posses a degree of exibility very similar to natural tissues, due to their signicant water content. Thus they nd potential biomedical applications owing to their excellent bio-compatibility, bio degradability and non toxicity. The main highlight of the work is that it is taking naturally occurring polymers such as agar and Chitosan for the synthesis of hydrogel. Different compositions of Chitosan/Agar hydrogels were formulated and optimised with respect to pH sensing, Urea absorption and dye adsorption. Chitosan/Agar hydrogels are found to be suitable and a potential candidate for several agricultural and bio medical applications.