论文部分内容阅读
本文将稀土络合物Ｎｄ（Ｐ２０４）３、Ｎｄ（Ｐ５０７）３、Ｎｄ（ｎａＰｈ）３、Ｎｄ（ａｃａｃ）３．３Ｈ２Ｏ与烷基铝组成的二元体系催化剂用于共聚马来酸酐（ＭＡｎ）与环氧丙烷（ＰＯ）获得成功．并采用１Ｈ—ＮＭＲ研究了共聚物三元组序列分布．结果表明，稀土络合催化剂为ＭＡｎ与ＰＯ共聚的优良催化刑，可得到高转化率、高交替度共聚物．共聚物数均分子量Ｍｎ和分子量分布分别为２０００—３０００、１．３—１．７，共聚物中ＭＡｎ的摩尔含量４０％以上．共聚物组成及序列分布与投料比、催化剂种类、溶剂性质等有关．理论计算表明，序列分布符合三级马尔可夫（Ｍａｒｋｏｆｆｉａｎ）过程．
In this paper, binary catalysts composed of rare earth complexes Nd (P204) 3, Nd (P507) 3, Nd (naPh) 3, Nd (acac) 3.3H2O and aluminum alkyls were used to copolymerize maleic anhydride (MAn) Success with propylene oxide (PO). The distribution of ternary copolymer was also studied by 1H-NMR. The results show that the rare earth complex catalyst is an excellent catalyst for the copolymerization of MAn and PO. Copolymers with high conversion and high degree of alternation can be obtained. The number average molecular weight Mn and molecular weight distribution of the copolymer were 2000-3000 and 1.3-1.7 respectively, and the molar content of MAn in the copolymer was more than 40%. Copolymer composition and sequence distribution and feed ratio, the type of catalyst, solvent properties and so on. Theoretical calculations show that the sequence distribution conforms to the third-order Markoffian process.