抗冲击共聚聚丙烯SP179及其级分的结构

Structure of impact propylene copolymer SP179 and its fractions

利用升温淋洗分级、差示扫描量热法、凝胶渗透色谱等分析了抗冲击共聚聚丙烯SP179及其级分的组成、相对分子质量、相结构。结果表明:SP179由丙烯均聚物、乙丙橡胶和可结晶的乙丙嵌段共聚物组成。其中,可结晶的乙丙嵌段共聚物含有少量橡胶相,通过偏光显微镜观察发现可结晶的乙丙嵌段共聚物为不完整的球晶;可结晶的乙丙嵌段共聚物与乙丙橡胶相、丙烯均聚物相具有较好的相容性;乙丙橡胶相降低了SP179球晶的结晶完整性。

The composition, relative molecular mass and crystallization behavior of the impact ethylene-propylene copolymer, SP179, were analyzed by means of temperature rising elution fractionation（TREF）, scan-ning electron microscopy（SEM）, gel permeation chromatograph（GPC）, etc. The results confirm that the im-pact copolymer consists of homopolypropylene, ethylene-propylene rubber（EPR） and crystallizable ethylene-propylene block copolymer. Crystallizable ethylene-propylene block copolymer contains small amounts of EPR, its spherical crystals are imperfective and ethylene-propylene block copolymer has better compatibility with EPR and homopolypropylene by polarized light microscope（PLM）. EPR decreases crystalline perfection of SP179 spherical crystals.