胺基双酚钴在合成极性单体与苯乙烯嵌段共聚物中的应用

Sequential Synthesis of Well-defined Poly(vinylacetate)-block-polystyrene Using Cobalt Complexes by Dispersion Polymerization

采用低成本、高活性胺基-双酚钴配合物调控的自由基聚合(CMRP)和催化链转移反应(CCT)对乙酸乙烯酯或丙烯酸叔丁酯与苯乙烯单体进行了共聚反应。以钴配合物为催化剂、偶氮二异丁腈(AIBN)为引发剂、聚乙烯吡咯烷酮(PVP)为分散剂,通过溶液聚合方法得到的聚乙酸乙烯酯和聚丙烯酸叔丁酯作为大分子引发剂,引发苯乙烯的分散聚合,从而获得具有较低分子量分布(~1.93)的丙烯酸叔丁酯和苯乙烯的共聚物及乙酸乙烯酯和苯乙烯的共聚物(PVAc-b-PS和PtBA-b-PS),数均分子量随单体转化率线性增加。运用凝胶渗透色谱、核磁共振波谱、扫描电子显微镜等测试手段对合成的嵌段共聚物进行了表征。

The copolymerization of vinyl acetate or tert-butyl acrylate and styrene monomer was carried out by using low-cost,highly active amino-bis(phenolate)cobalt complex-controlled radical polymerization(CMRP)and catalytic chain transfer reaction(CCT).With cobalt complex as catalyst,azobisisobutyronitrile(AIBN)as initiator,polyvinylpyrrolidone(PVP)as dispersant,polyvinyl acetate and poly(tert-butyl acrylate)obtained by solution polymerization as macroinitiator,the dispersion polymerization of styrene was initiated to obtain copolymers of tert-butyl acrylate and styrene and copolymers of vinyl acetate and styrene(PVAc-b-PS and PtBA-b-PS)copolymers with lower molecular weight distribution(~1.93).The number average molecular weight increases linearly with monomer conversion.The synthesized block copolymer was characterized by gel permeation chromatography,nuclear magnetic resonance spectroscopy,scanning electron microscope and other test methods.