聚丙烯接枝马来酸酐及其离聚物的非等温结晶动力学

用 Ｄ Ｓ Ｃ 测定了固相接枝法制备的聚丙烯接枝马来酸酐（ Ｐ Ｐ ｇ Ｍ Ａ Ｈ） 及其３ 种５ 个离聚物在不同冷却速率的非等温结晶动力学．分析了结晶峰温（ Ｔｍａｘ） 、结晶起始温度（ Ｔ０） 、结晶峰的初始斜率（ Ｓｉ） 及结晶峰的半高宽（ Δｗ ） 等结晶峰参数；用 Ａｖｒａｍｉ 方程和综合了 Ａｖｒａｍｉ Ｏｚａｗａ 方程的方法处理非等温结晶动力学．对于全部样品在所有的冷却速率下， Ａｖｒａｍｉ 指数ｎ 值均在２５ ～２８ 之间，说明聚丙烯结晶行为没有改变；但同时发现接枝及离子化后，成核速率加快，晶粒分布变窄，结晶总速率增大，与等温结晶动力学得到的结论一致．

NON-ISOTHERMAL CRYSTALLIZATION BEHAVIOR OF MALEIC ANHYDRIDE GRAFT POLYPROPYLENE AND ITS IONOMERS

The non isothermal behaviors for maleic anhydride graft polypropylene and its Na+ , Mn2 + , Ca2 + ionomers under different cooling rates have been studied by D S C. Theanalysis of exothermic peaks has been done in terms of peak temperature ( Tmax) ,startingcrystallization temperature( T0) ,initialslope ( Si) and width of half height (Δw) . Avramiequation and a combination of Avrami Ozawa method were used to analyzee the non isothermalcrystallization kinetics. Allionomers had higher rate of nucleation ,characterizedby the higher values of Si ,overallrate of crystallization ,characterized by the higher valuesof ( Tmax - T0) ,and narrower crystallite size distribution ,characterized by thelower valuesof Δw ,than those of pure P Pand P P g M A H. The plots of Si versus.temperature ( T0 or Tmax) are more accurate and valuable than the plots vs. cooling rate at evaluating thecrystallization characteristic of samples. The factthat allsamples had Avramiexponentsin arange of 2 .5 ～2 .8 implied the mode of P Pcrystallization was not changed by varied coolingrates by the solid graft modification .