超临界CO_2中马来酸酐和乙酸乙烯酯的共聚合

Copolymerization of maleic anhydride and vinyl acetate in supercritical carbon dioxide

以超临界CO2为反应介质进行了马来酸酐(MA)和乙酸乙烯酯(VAc)的共聚合,制备了不同结构的MA和VAc共聚物[P(MA-co-VAc)],研究了该聚合及产物的性能。结果表明:单体配比和反应压力对产物的形态影响较大,当n(VAc)/n(MA)为1∶1,反应压力大于或等于15 MPa时,可制得P(MA-co-VAc)白色固体粉末,VAc的转化率达99.10%。该聚合体系压力变化与反应进程是同步的,聚合体系压力恒定时,表明该聚合已经结束。

The authors carried out copolymerization of maleic anhydride（MA） and vinyl acetate（VAc） in supercritical carbon dioxide, and prepared copolymers of MA and VAc [P（MA-co-VAc）] with different structures. The polymerization and properties of the resultant copolymers were studied. The results show that the molar ratio of monomers and polymerization pressure has great impact on the morphology of the copolyrners. The P（MA-co-VAc） in the form of white solid powder can be obtained when the molar ratio of MA to VAc is 1：1 and the reaction pressure is no less than 15 MPa. The conversion of VAc reaches 99.10% under the above conditions. The variation in pressure of the polymerization system is synchronized with the reaction progress; the polymerization reaction is over once the pressure of the polymerization system no longer varies.