Morphology of Polypropylene/Ethylene-Propylene Copolymer Blends

• Published in: KOBUNSHI RONBUNSHU Vol. 51; no. 9; pp. 569 - 576
• Main Authors: NOMURA, Takao, NISHIO, Takeyoshi, MORIYA, Satoru, HASHIMOTO, Mikio
• Format: Journal Article
• Language: Japanese
• Published: Tokyo The Society of Polymer Science, Japan 01.01.1994; Tsukiji daisan nagaoka
• Subjects: Amorphous Phase; Annealing; Impact Resistance; Micro-Craze; Morphology; PP and Elastomer Blends; Rubber Matrix Structure
• ISSN: 0386-2186; 1881-5685
• DOI: 10.1295/koron.51.569

The Super Olefine Polymer (SOP) used in automobile bumpers and for some other applications is a polypropylene (PP) -based composite which consists of impact-resistant poly (propylene-ethylene) copolymers and ethylene-propylene copolymers (EPR). Its excellent properties can not be explained by using the conventional PP matrix structure. In this report, we chose the PP/EPR blend as the simplest model of SOP and we examined the structures of the blends by small angle X-ray scattering (SAXS), dynamic visco-elastic measurements and transmission electron microscopy (TEM). The results obtained by SAXS analysis and dynamic measurement method showed that EPR dissolved into the PP amorphous phase and that the length of amorphous PP increased. The observation of the fracture portion of PP/EPR blends by using TEM showed that a blend where EPR was dissolved into PP amorphous phase had micro-crazes which were different from the conventional craze formation. The morphology of the PP/EPR blend is concluded to be “rubbermatrix. ” The “rubber matrix” blends will be impact-improved materials.