丙烯/1-丁烯和丙烯/乙烯无规共聚物的表征及性能研究

采用摩尔含量接近的两个单体乙烯和1-丁烯分别无规共聚聚丙烯样品,用三氯苯进行室温可溶物和不溶物的分离,采用凝胶渗透色谱、13C核磁共振波谱及热分析等方法对两种共聚聚合物及其分离物进行表征,探讨了乙烯和1-丁烯作为共聚单体对聚丙烯树脂结构和性能的影响.结果表明,与乙烯相比,1-丁烯更趋向于共聚在较长的聚丙烯分子链上,其结果导致丙烯/1-丁烯无规共聚聚丙烯的可溶物含量更低.同时,对两种无规共聚物结晶性能的差异以及对光学性能和动态力学性能的影响研究表明,如果共聚单体含量接近,丙烯/1-丁烯无规共聚物结晶度更高;透明制品雾度相同时,丙烯/1-丁烯无规共聚物的刚性更高.

The characterization and performance study of propylene/1- butylene and propylene/ethylene random copolymers

Two random propylene-based copolymers with close mole content of ethylene and 1-butene as co-units were fractionated into solubles and insolubles in 1,2,4-trichlorobenzen at room temperature. The two copolymers and the fractions were characterized by using gel permeation chromatography, ^13C nuclear magnetic resonance（NMR）, thermal analysis, etc. The effect of ethylene and 1-butene on structure and properties of polypropylene resin was discussed. The results showed that 1-butene tended to copolymerize on longer molecular chains of polypropylene compared with ethylene, and that led to lower soluble content in propylene/1-butene copolymer. It was also showed that with close mole comonomer content the two samples had same clarity and the propylene/1-butene random copolymer had higher rigidity than ethylene/propylene random copolymer.