通过活性自由基聚合制备结构精致的大分子单体

合成了一种新型单体引发转移终止剂，2-N,N-二乙基二硫代氨基甲酰氧基乙酸烯丙酯(ADCA)。在紫外光照射下，引发剂量的ADCA能分别引甲基丙烯酸甲酯(MMA)和苯乙烯(St)聚合，聚合过程具有活性聚合的特征，即所得聚合物的数均分子量随着单体转化率的增加而线性增加，经1^HNMR分析证明，所得聚合物为一大分子单体，具有α-烯丙氧基羰甲基和ω-N,N-二乙基二硫代氨基甲酰氧基(DC)基团的精致结构。大分子单体的分子量可通过控制聚合过程中的单体转化率和所用引发剂浓度来调节。运用ESR技术证明了聚合反应机理。

Syntheses of well-defined macro-monomers by living readical polymerization

A novel monomer-iniferter, allyl 2-N,N-diethyldithiocarbamylacetate (ADCA), has been successfully synthesized. It was used as a photoiniferter to initiate methyl methacrylate (MMA) and styrene (St) polymerization, respectively, under UV light irradiation at ambient temperature. The polymerizations exhibit the living radical polymrization characteristics, i. e., the molecular weight of the obtained polymers increases linearly with the increasing monomer conversion. In all cases, the number of the averatge end group of diethyldithiocarbamyl (DC) in polymers is about 1. 1^H NMR analyses show that the obtained polymers are macro-monomers functionalized with an α-allyloxycarbonylmethylene group and an ω-DC group. ESR studies reveal that polymerization mechanism is based on a reversible termination of propagating radical by DC group.