Thermal degradation and swelling of thermoplastic vulcanizates from NBR/SAN and NBR/Scrap computer plastics blends

Abstract

Thermoplastic elastomeric blends of nitrile rubber (NBR)/poly(styrene- coacrylonitrile) (SAN) and NBR/scrap computer plastics (SCP) based on acrylonitrile-butadiene-styrene terpolymer (ABS) were prepared. Thermoplastic elastomeric blends of NBR/SAN containing various amounts of a model waste nitrile rubber powder (w-NBR) were also prepared. Thermogravimetric analysis of the above blends was performed in a nitrogen atmosphere. Both Friedman and Flynn-Wall-Ozawa methods were used for the evaluation of activation energies of thermal degradation of these blends. The dynamically vulcanised blends exhibit higher amount of activation energies for thermal degradation than the unvulcanised ones. Swelling studies were performed in various solvents having different solubility parameter values and maximum swelling was found to occur in a solvent having a solubility parameter that was closer to that of the blend components, i.e., around 20MPa1/2. Dynamically vulcan-ised blends show excellent resistance to IRM #903 oil as well as four chosen solvents possessing different solubility parameters (E).