Counits Content and Stretching Temperature-Dependent Critical Stress for Destruction of γ Crystals in Propylene-Ethylene Random Copolymers.

ABSTRACT: Tensile deformation behavior of three random propylene-ethylene copolymers with the same molecular weight and different contents of counit was investigated at different temperatures from room temperature to close to melting point via tensile tests, step-cycle tests, and in situ wide-angle X-ray diffraction techniques. Upon stretching, the original crystalline lamellae must be destroyed, generating new highly oriented ones. A critical stress has been suggested, under which the original crystallites can be destructed. The propylene-ethylene copolymer samples in pure γ-form transformed gradually into α-form during tensile stretching. This crystalline transition proceeded via a destruction (melting) of the original γ-form crystals followed by recrystallization of the freed polymeric chain segm

SUBMITTER: Zhao J 

PROVIDER: S-EPMC6645210 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature