Influence of the Molecular Structure on Slow Crack Growth Resistance and Impact Fracture Toughness in Cr-Catalyzed Ethylene-Hexene Copolymers for Pipe Applications

摘要

In this study we correlate parameters describing molecular structure(molar mass distribution,short chain branching content,intermolecular heterogeneity )of different ethylene-hexene Cr-catalyzed copolymers,with slow crack growth and rapid crack propagation resistances respectively measured with Bent Strip and Charpy tests.The PTREF technique,coupled with classical techniques ,was used.Two new indices were proposed to correlate mechanical properties and molecular structure.