Influence of Maleation of Ground Rubber Tyre (GRT) on the Thermorheological behaviour of Thermoplastic Elastomers Based on Ethylene Propylene Diene Rubber,GRT and Ethylene-co-acrylic acid

The thermorheological behaviour of thermoplastic elastomeric blends based on both ground rubber tyre (GRT) and maleic anhydride grafted GRT (m-GRT) has been studied. The blend composition based on m-GRT exhibits a higher melt viscosity than the corresponding control blend based on GRT. The former exhibits lower die swell and less melt fracture at low shear rates than the latter, when extruded at 180°C through a capillary rheometer. At high shear rates, however, both the blends exhibit melt fracture. There is apparently some interaction between m-GRT and the matrix, which is evident from dynamic mechanical analysis. The m-GRT causes a significant lowering in tanδ at temperatures higher than the T_g of the blend.