自由基引发的高转化率甲基丙烯酸甲酯-苯乙烯共聚物的交叉分级

Cross Fractionation of Radical Initiated Methyl Methacrylate Styrene Copolymer with High Conversion

用自由基引发的高转化率甲基丙烯酸甲酯-苯乙烯共聚物在25.0±0.1℃的丙酮-乙腈、一氯代正丁烷-环己烷中进行交叉分级,测定了所得到的35个级分的化学组成和分子量。从实验结果可知,Stockmayer理论对低转化率共聚物及高转化率的MS共聚物的化学组成分布的计算都适用,计算所得分布与交叉分级实验结果基本相符。

Methyl methacrylatc-styrene copolymers with high conversion initiated by the radical were cross-fractionated in two solvent-nonsolvent,acetone-acelonitrile and n-butyl chloridc-cyclohcxane,35 fractions were obtained and their chemical compositions and molecular weights were determined.The results show that the application range of Stockmayer equation should include copolymer with high conversion,if a correction was made to offset the deviation due to the changs of reactivity ratios during the ccpolymerization,a chemical composition distribution curve which is basically in accord with the experimental datum was obtained.