Morphology and Properties of PP In-reactor Alloys Prepared with a MgCl2/TiCl4/Diisobutyl Phthalate/Phosphate Tris-methylphenyl Ester Catalyst System  

作　　者：ZHANG Chunyu DONG Bo ZHANG Hexin HU Yanming ZHANG Xuequan 

机构地区：[1]Key Laboratory of Synthetic Rubber of Chinese Academy of Sciences, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China

出　　处：《Chemical Research in Chinese Universities》2018年第1期145-150,共6页高等学校化学研究（英文版）

基　　金：Supported by the National Natural Science Foundation of China（No.U1462124）.

摘　　要：A series of polypropylene（PP）/poly（ethylene-co-propylene） in-reactor alloys with different ethylene contents was prepared through a two-stage polymerization process using a MgCl2/TiCl4/diisobutyl phthalate/phosphate tris-methylphenyl ester catalyst system. The ethylene content, particle shape, fractured surface, and glass-transition temperature（Tg） of the obtained PP in-reactor alloys were characterized by means of nuclear magnetic resonance, scanning electron microscopy（SEM）, and dynamic mechamcal analysis（DMA）. The ethylene content of the PP alloys increased from 2.34% to 26.69% when the propylene/ethylene feed ratio was increased from 66/34 to 54/46（molar ratio）. Morevoer, the increment in ethylene content increased the notched Izod impact strength of the resulting PP alloys. The impact strength of the PP alloy with an ethylene content of 26.69% was 55.8 kJ/m^2, which is 12.7 times that of isotactic polypropylene. The results of DMA and SEM analysis reveal that ethylene-propylene random copolymer（EPR） in the PP alloy has a low Tg of ca. -50℃ and a high interface compatibility with the PP matrix. The excellent impact performance of the PP alloy can be attributed to the uniform dispersal of EPR in the alloy particles and PP matrix.A series of polypropylene（PP）/poly（ethylene-co-propylene） in-reactor alloys with different ethylene contents was prepared through a two-stage polymerization process using a MgCl2/TiCl4/diisobutyl phthalate/phosphate tris-methylphenyl ester catalyst system. The ethylene content, particle shape, fractured surface, and glass-transition temperature（Tg） of the obtained PP in-reactor alloys were characterized by means of nuclear magnetic resonance, scanning electron microscopy（SEM）, and dynamic mechamcal analysis（DMA）. The ethylene content of the PP alloys increased from 2.34% to 26.69% when the propylene/ethylene feed ratio was increased from 66/34 to 54/46（molar ratio）. Morevoer, the increment in ethylene content increased the notched Izod impact strength of the resulting PP alloys. The impact strength of the PP alloy with an ethylene content of 26.69% was 55.8 kJ/m^2, which is 12.7 times that of isotactic polypropylene. The results of DMA and SEM analysis reveal that ethylene-propylene random copolymer（EPR） in the PP alloy has a low Tg of ca. -50℃ and a high interface compatibility with the PP matrix. The excellent impact performance of the PP alloy can be attributed to the uniform dispersal of EPR in the alloy particles and PP matrix.

关 键 词：Polypropylene m-reactor alloy PHOSPHATE Ziegler-Natta catalyst Ethylene-propylene random copolymer Toughening mechanism 

分 类 号：TQ225.122[化学工程—有机化工] TL351.6[核科学技术—核技术及应用]