Dynamic Mechanical and Morphological Behavior ofBlends of Polystyrene and Polyacrylonitrile-g-(ethylene-co-propylene-co-diene)-g-styrene Prepared by in SituPolymerization of Styrene

摘要

PS/AES blends were prepared by in situpolymerization of styrene in the presence of AES elasto-mer, a grafting copolymer of poly(styrene-co-acrylonitrile)– SAN and poly(ethylene-co-propylene-co-diene)–EPDMchains. These blends are immiscible and present complexphase behavior. Selective extraction of the blends compo- degree between PS and AES was not high enough toensure the morphological stability against changes duringprocessing in the melting state. The drastic change ofEPDM morphology from continuous to disperse phase hasas consequence a decrease in the intensity of the loss mod-ulus peaks corresponding to the EPDM glass transition.However, the storage modulus at temperatures betweenthe glass transition of EPDM and PS/SAN phases doesnot change significantly. This effect was attributed to thepresence of the SAN rigid chains in the AES.