13C NMR方法研究聚甲基丙烯酸羟乙酯的立构序列分布

用C_o^oγ-射线辐照聚合方法,在20%(V/V)的乙醇溶液中成功地制备出了线性聚甲基丙烯酸羟乙酯。从在20MHz和35℃条件下获得的¹³CNMR光谱中,观察到该聚合物的二单元组、三单元组和五单元组单体序列分布。将所观察到的各类型碳的强度分布与通过柏努利统计模型所计算出的值进行比较,对各峰进行归了属。其结果表明,该聚合过程符合柏努利过程。用这种方法制备的聚甲基丙烯酸羟乙酯的三单元组规整度分别为:间规立构70.2%;杂规立构27.2%等规立构2.6%。

CONFIGURATION SEQUENCE DISTRIBUTION OF POLY (HYDROXYETHYL METHACRYLATE) BY 13C NMR

Linear poly(hydroxyethyl methacrylate) has been prepared by γ-radiation irradiation polymerization in 20%(v/v) alcohol solution.Dyad, triad and pentad comonomer distributions for the polymer were observed in ¹³C NMR spectrum obtained at 20 MHz and 35℃ condition. Assignments were made by comparing observed intensity distribution for each carbon type with those calculated assuming Bernoullian statistical model. The results show that the polymerization process conform with that of Bernoullian.The poly (hydroxyethyl metharylate) prepared by this method has a tactic triad content of 70.2% syndic., 27.2% hetero., and 2.6% iso..