乙烯基单体-N-苯基马来酰亚胺共聚物序列结构研究

Studies on the Sequence Structure of Vinyl Monomer N phenylmaleimide Copolymers

用ＮＭＲ谱研究了甲基丙烯酸甲酯（ＭＭＡ）－Ｎ－苯基马来酰亚胺（ＰＭＩ）、苯乙烯（Ｓｔ）－ＰＭＩ共聚物的序列结构．结果表明，ＭＭＡ－ＰＭＩ共聚物单元属无规序列分布，Ｓｔ－ＰＭＩ共聚物单元属交替序列分布．由１ＨＮＭＲ结果可得ＭＭＡ－ＰＭＩ共聚物空间立构部分信息，由１３ＣＮＭＲ三单元组实验结果算得的序列长度与末端基理论计算结果一致，且ＭＭＡ－ＰＭＩ共聚物链属一级Ｍａｒｋｏｖ链．

The sequence structure of methyl methacrylate (MMA) N phenylmaleimide (PMI) and styrene (St) PMI copolymers was studied in detail with NMR spectroscopy. MMA PMI copolymer was in random sequence distribution, and St PMI copolymer was alternating in structure. Some stereo information of MMA PMI copolymer could be obtained from 1H NMR result. The sequence length obtained from the triad of copolymer by 1 C NMR was in agreement with that calculated from the reactivity ratios. From the triad of copolymer by 13 C NMR, the copolymer chain of MMA PMI was proved being one order Markov chain. More suitable propagation reactions were proposed from the deviation of sequence distribution of St PMI copolymer.