Efficiency of high energy electrons to produce polypropylene/natural rubber-based thermoplastic elastomer

High energy electrons have been used to induce chemical crosslinking in 50/50 blend of polypropylene and natural rubber. The blend morphology was generated during melt mixing and not changed by high energy electron treatment in the solid state at room temperature. The variation of absorbed dose (150-350 kGy) at fixed electron energy (1.5 MeV) brings a dramatic change in the properties of the polymer blend. In addition, the effect of a polyfunctional monomer (PFM) and the absorbed dose on the tensile properties of the polymer blend was investigated. The presence of a PFM led to blends having an elongation at break of about 350% and a tensile strength of nearly 14 MPa after the treatment with a comparatively low dose of 150 kGy. The morphology of the blends was found to be co-continuous. A plausible mechanistic pathway for the phenomenon leading to enhancement of property has been suggested for better understanding of structure-property-relationship. POLYM. ENG. SCI., 2013. (c) 2012 Society of Plastics Engineers.