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通过AB2型聚合单体4-(2-羟基乙氧基)苯甲醛二甲缩醛与B2型核分子苯甲醛二甲缩醛的缩醛转移聚合反应,反应过程中不断排出低沸点的醇,合成了具核、骨架可水解的超支化聚缩醛(HBPAs).实验表明,HBPAs的分子量,多分散性和聚合度随着核比例的改变发生明显的变化.增加核比例,聚合物的分子量,多分散性和聚合度均降低.HBPAs在弱酸性条件下,骨架发生水解,生成4-(2-羟基乙氧基)-苯甲醛.研究发现,核比例对于聚合物降解速率有明显的影响,增加核比例,聚合物的降解速率加快.这表明,通过加入核分子,可以在一定程度上调控超支化聚缩醛的结构与性能.
Through the acetal transfer polymerization of AB2-type polymeric monomer 4- (2-hydroxyethoxy) benzaldehyde dimethyl acetal and B2 nuclear molecule benzaldehyde dimethyl acetal, low boiling point alcohol is continuously discharged during the reaction process, The results showed that the molecular weight, polydispersity and degree of polymerization of HBPAs changed obviously with the increase of nuclear ratio.With the increase of nuclear ratio, the molecular weight of the polymer , Polydispersity and degree of polymerization were all decreased.HBPAs hydrolyzed to form 4- (2-hydroxyethoxy) -benzaldehyde under mildly acidic conditions.It was found that the ratio of nuclei had a significant effect on the degradation rate of polymer , Increasing the nuclear ratio and accelerating the degradation rate of the polymer showed that the structure and properties of the hyperbranched polyacetal can be controlled to a certain degree by adding the nuclear molecule.