聚丙烯/笼型聚硅倍半氧烷的非等温结晶及其动力学研究

采用熔融挤出共混的方法制备了均聚聚丙烯(iPP)/笼型八聚(异丁基)硅倍半氧烷(OIBS)复合材料,并用DSC法研究了此种复合材料的非等温结晶行为,当OIBS质量分数为1%和30%的样品结晶峰温T_p高于iPP的T_p,而OIBS质量含量为5%和10%样品的T_p低于iPP的T_p值,OIBS含量对结晶起始温度T₀和结晶峰半高宽W_1/2·h的影响与T_p相似.说明适量的OIBS对iPP具有异相成核作用。采用修正Avrami方程的Jeziorny法及莫志深法对数据进行处理并计算出结晶动力学参数。结果表明适量OIBS的加入可提高iPP的结晶速率。

Non-isothermal crystallization kinetics of iPP/POSS composites

The non-isothermal crystallization kinetics of the iPP/OIBS (octa-(iso-butyl) silsesquioxane) composites prepared by a twin extruder was studied by a differential scanning calorimetry (DSC). The crystallization parameters such as the peak temperature (T_p), starting crystallization temperature (T₀) and the width of half-height (W_1/2·h ) were influenced by the concentration of OIBS. The changes of these parameters demonstrated that with a certain concentration of OIBS, the crystallization temperature of the samples might increase and the uniformity of crystal might improve,which show OIBS has a heterogeneous nucleation during non-isothermal crystallization process of iPP.The kinetics parameters were calculated by the modified Avrami theories of Jeziorny and Mozhishen,respectivity.The Z_c and F(T) also indicated the crystallization rate could improved by a proper concentration of OIBS.