A preliminary study on the new thermoplastic vulcanizates

Thermoplastic elastomers (TPEs) are new type of elastomer materials with comparable and sometimes better mechanical properties than conventional elastomers, while having processing characteristics of thermoplastic materials. Thermoplastic vulcanizates (TPE-V) are elastomer/thermoplastic polymer microheterogenic blends in which elastomer phase is crosslinked and dispersed in a continuous thermoplastic matrix. The subject of this study was evaluation of the phase structure and mechanical properties of the TPE-Vs obtained by reactive processing in the molten state of PP and ethylene-octene elastomer (EOE) blend using silane/moisture as crosslinking system. Morphology was studied by scanning electron microscopy (SEM) and thermal behavior of the blends was studied by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and differential thermal analysis (DTA). It was observed that both thermal behavior and mechanical properties of the compositions were very dependent on blend composition when specimens are subjected to heat or mechanical loads. Glass transition temperature (Tg) decreases with increase in concentration of elastomer in TPE-V.