抗冲共聚聚丙烯的组成及其结晶行为

Chemical composition and crystallization of IPC

采用二甲苯可溶物分析仪和分析型升温淋洗分级仪表征了两种二甲苯可溶物含量相近、二甲苯可溶物中乙烯含量不同的抗冲共聚聚丙烯(IPC)。利用溶解沉淀法分离出两种IPC试样的室温可溶物,得到了两个室温不溶物。采用非等温结晶和等温结晶方法研究了两种IPC原样及室温不溶物的结晶行为。采用小角X射线散射方法研究了两种IPC原样及室温不溶物的片晶厚度和长周期。结果表明:在二甲苯可溶物含量相近的前提下,二甲苯可溶物对不溶物结晶行为的影响与二甲苯可溶物中的乙烯含量有关。在二甲苯可溶物中乙烯含量较低的试样中,不溶物的结晶受可溶物的影响更明显。

Two impact polypropylene copolymers(IPC)with similar xylene soluble(XS)content anddifferent ethylene content in XS(C2in XS)were characterized by XS analyzer and analytical temperature risingelusion fractionation(A-TREF).Two soluble and two insoluble fractions were removed at room temperaturefrom two IPCs by means of dissolution-precipitation method.The crystallization behavior of two IPCs and twoinsoluble fractions were observed by non-isothermal and isothermal crystallization respectively.The long periodand the lamella thickness of two IPCs and insoluble fractions were determined by small angle X-ray scattering(SAXS)respectively.The results show that C2in XS exerts impact on crystallization behavior of the insolublefractions when XS content are similar in samples;the soluble fractions contribute more on the crystallizationbehavior of the insoluble fractions in samples of low C2in XS.