| abstract |
Certain thermoplastic polymer blends have tensile strengths greater than that of any one polymer component. The blends comprise (1) at least one ethylene-propylene-diene (EPDM) polymer, (2) at least one ethylene-propylene (EP) polymer, and (3) optionally, at least one polyethylene. The EPDM and EP polymers each have ethylene content, unstretched crystallinity, and Mooney viscosity within a specific range. The blends are prepared by mixing physically the polymer components under heat and shear conditions. No curing or crosslinking agents are needed to obtain the superior tensile strengths of the thermoplastic blends. The blends are useful to prepare tubing, wire and cable insulation, molded items and the like. |