Organic-inorganic nanocomposites consisting of co-poly(vinyl chloride-vinyl acetate-vinyl alcohol) and silica were prepared via sol-gel process. Two types of hybrids were prepared, one in which interactions between hydroxyl group present in the copolymer chain and silanol groups of silica network were developed. In the second set, extensive chemical bonding between the phases was achieved through the reaction of hydroxyl groups on the copolymer chains with 3-isocyanatopropyltriethoxysilane (ICTS). Hydrolysis and condensation of tetraethoxysilane and pendant ethoxy groups on the chain yielded inorganic network structure. Mechanical and thermal behaviors of the hybrid films were studied. Increase in Young's modulus, tensile strength, and toughness was observed up to 2.5 wt % silica content relative to the neat copolymer. The system in which ICTS was employed as binding agent, the tensile strength and toughness of hybrid films increased significantly as compared to the pure copolymer. Thermogravimetric analysis showed that these nanocomposite materials were stable up to 250 C. The glass transition temperature increases up to 2.5 wt % addition of silica in both the systems. Field emission scanning electron microscope results revealed uniform distribution of silica in the copolymer matrix.

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This technical study deals with the experimental evaluation of four different safety gloves, used in Pakistan for protection of hands. The samples were prepared and tested according to their standard test methods EN-388. The samples for EN388 were subjected to three physical tests; puncture resistance (N), abrasion resistance (cycles), tear-resistance (N). The results revealed that the performance levels of synthetic leather/ PVC gloves were found higher than other gloves.

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