Structure and Properties of Peroxide Dynamicaliy Vulcanized Polypropylene/Ethylene-Propylene-Diene/ Zinc Dimethacrylate Composites

摘要

Peroxide dynamically vulcanized thermoplastic olefin (TPO) based on polypropylene (PP)/ethylene-propylene-diene (EPDM) loaded with zinc dimethacrylate (ZDMA) was prepared. The addition of ZDMA improved the complex viscosity of the resulting materials in the melt state significantly, as determined from oscillatory rheology analyses. Dynamic mechanical analysis (DMA) and transmission electron microscopy (TEM) examinations were performed to evaluate the structure of the PP/ EPDM/ZDMA composite. Atomic force microscope (AFM) and scanning electron microscopy (SEM) were used to study the morphology. The degree of crystallinity was evaluated using X-ray diffraction method (XRD). The results revealed that incorporation of ZDMA resulted in a size reduction of the rubber droplets and improved the compatibility between rubber and PP phases. The nano-particles of the polymerized ZDMA (PZDMA) served as an effective nucleating agent for the crystallization of PP. The rheoiogical properties and mechanical properties were improved by ZDMA. Particularly, the izod impact strength of the PP/EPDM/ZDMA (80/20/6, w/w) composite is nearly 2 times higher than the PP/EPDM (80/20, w/w) and 12 times higher than the PP; besides, the elongation at break of the PP/EPDM/ZDMA (80/20/6, w/w) is 3 times higher than that of the PP/EPDM (80/20, w/w) and 6 times higher than the PP.