Influence of Spherulitic Microstructure on Deformation Mechanism in Isotactic Polypropylene

摘要

Thermoplastic polymers dissipate mechanical energy via either crazing or shear yielding.While semi-crystalline thermoplastics often show shear yielding behavior,researchers have reported signs of crazing in polypropylene.The aim of this investigation is to explore the correlation between microstructure and deformation mechanism in isotactic polypropylene.Uniaxial tensile test is incorporated.Thin films are studied via transmission optical microscopy(TOM).The results reveal formation of shear bands at spherulite boundaries at the point of yielding.