乙丙抗冲共聚聚丙烯结构的研究

Study on Structure of Impact Ethylene-Propylene Copolymer

采用升温淋洗分级、核磁共振、示差扫描量热、凝胶渗透色谱和扫描电子显微镜等方法研究了乙丙抗冲共聚聚丙烯(PP1740共聚物)的组成、序列结构、相对分子质量、热转变、相态结构和宏观性能。研究结果表明,PP1740共聚物由均聚聚丙烯、乙丙橡胶和可结晶的乙丙共聚物组成,具有优良的机械性能;均聚聚丙烯为PP1740共聚物提供刚性,乙丙橡胶可提高PP1740共聚物的抗冲性能;PP1740共聚物的相对分子质量分布呈多分散性,相对分子质量分布较宽;乙丙橡胶的相对分子质量较大,以直径1～2μm球型微粒均匀分布在聚丙烯基体中,有利于提高PP1740共聚物的冲击强度;PP1740共聚物的熔点较高,耐热性好。

The composition, sequential structure, relative molecular mass, heat transformation, phase structure and properties of the impact ethylene - propylene copolymer （ PP1740 copolymer） were characterized by means of temperature - raise elution fractionation （ TREF）, NMR, DSC, GPC and SEM. PP1740 copolymer is a multi phase copolymer, composed of homo -polypropylene, ethylene - propylene rubber （ EPR）, and crystallizable propylene - ethylene copolymer. Homo - polypropylene part offers rigidity and EPR part offers impact strength. The relative molecular mass distribution of PP1740 copolymer is broad. EPR with large relative molecular mass distributes in polypropylene continuous base homogeneously in form of globular granules 1 - 2 μm in diameter and enhances impact strength of PP1740 copolymer. The melting point of PP1740 copolymer is quite high and heat resistance is promising.