无规共聚聚丙烯的结构与性能研究

通过核磁共振(13CNMR),红外光谱(IR)和差示扫描量热法(DSC)等表征分析手段对无规共聚聚丙烯(PPR)的物理结构与机械性能进行研究。结果表明:PPR具有典型的无规共聚物的结构,乙烯基团较均匀的无规分散于丙烯分子长链中;在分子序列结构中,EE和EEE联排的结构并不多;乙烯含量低的EP接点的含量偏低,相应的抗冲击强度偏低,乙烯含量高的EP接点的含量偏高,相应的抗冲击强度较高。乙烯在丙烯分子长链中的无规插入也适当的降低了共聚物的熔点。

Investigation on the Property and Structure of the Random Polypropylene Copolymer

The physical structures and mechanical properties of the random polypropylene copolymer PPR were investigated by using 13C NMR,IR and DSC methods.The results obtained from IR indicates that PPR is the typical random copolymer with Ethylene randomly distributed in the polypropylene chains;13C NMR results indicates that the content of EE and EEE structure is lower in the molecular sequence structure;the content of EP structure is lower in the copolymer with lower Ethylene content and the relative impact toughness is lower,while the content of EP structure is higher in the copolymer with higher Ethylene content and the relative impact toughness is higher.The random distribution of Ethylene in the polypropylene molecular chains properly decreases the melting point of the copolymer.