摘要
本文以二甲苯（ＤＭＢ）为溶剂，过氧化二苯甲酰（ＢＰＯ）为引发剂，采用溶液聚合的方法，在一定条件下使甲基丙烯酸（ＭＡＡ）与等规聚丙烯（ＩＰＰ）发生接枝共聚制得接枝物。红外光谱证实了接枝物ＩＰＰ－ｇ－ＭＡＡ的存在。实验表明：反应温度、反应时间和单体浓度对接枝共聚反应影响很大。当反应温度在１００℃以下时，随反应温度的增加，接枝率显著增大；而反应温度高于１００℃以后，提高温度接枝率呈下降趋势。延长反应时间可以提高接枝率，反应２ｈ后则接枝率增加缓慢趋于稳定。ＭＡＡ单体浓度较低时，接枝率随单体浓度增大而增加；当其浓度大到某一数值时（本实验为０．４９ｍｏｌ／Ｌ），接枝率达到一极值，随后下降。从偏光显微镜观察，接枝共聚后的ＩＰＰ－ｇ－ＭＡＡ仍呈晶体形貌，当接枝率低于一定数值时（本实验为１９．６％），晶体细而规整，有球晶特征，随着接枝率的增加，晶体有增大趋势，规整程度降低。
An IPP g MAA graft polymer was synthesized from the graft polymerization of methacrylic acid(MAA) onto isotactic polypropylene (IPP), in which Xylene (DMB) was used as solvent, and benzoyl peroxide (BPO) as initiator. The graft reactant IPP g MAA was identified by means of IR spectra. It was shown by experiment that the reaction temperature and time, as well as the monomer concentration, had great effect on the reaction. When the reaction temperature was lower than 100℃, the grafting rate increased obviously with the increase of the tempearature; when the temperarure was higher than 100℃, the grafting rate decreased with the increase of the temperature. The grafting rate could be increased by prolonging the reaction time,but the increase of the grafting rate would tend to be slow and stable when the reaction went on for 2h. The grafting rate increased with the increase of the monomer concentration when the MAA monomer concentration was low, and when the concentration was up to a certain level (0.49 mol/L in this experiment), the grafting rate increased to a limiting value first, and then began to decrease. It was shown by polarizing microscope that the grafting rate was lower than a certain level(19.6% in this experiment),the crystal was thin and tidy, characterized by spherulite, and the crystal tend to be bigger when the grafting rate increased, with a decrease of the regularity of the crystal. The velocity ratio of the crystallization increased with the increase of the grafting rate.
出处
《塑料工业》
CAS
CSCD
北大核心
1996年第4期69-71,共3页
China Plastics Industry
关键词
聚丙烯
甲基丙烯酸
接枝共聚
结晶
PP MMA Graft Copolymerization Grafting Rate Crystallizability
