N-咔唑基RAFT试剂在RAFT聚合中的阻滞效应

采用膨胀计法研究了N-咔唑二硫代甲酸苄基酯（BCBD）、N-咔唑二硫代α-甲基苄基酯（PCBD）、N-咔唑二硫代甲酸异丙苯酯（CCBD）和N-咔唑二硫代异丁腈酯（CYCBD）4种RAFt试剂在苯乙烯、丙烯酸乙酯和甲基丙烯酸甲酯的RAFt聚合中的阻滞效应，并考察了RAFt试剂用量、单体种类和聚合温度对阻滞效应的影响，结果表明，上述4种以咔唑为z基团的RAFt试剂在RAFt聚合中表现出明显的阻滞作用，且阻滞效应与RAFt试剂的结构密切相关，在相同情况下，阻滞效应由大到小依次为CCBD〉PCBD〉BCBD〉CYCBD，

Retardation Ability of N-Carbazyl RAFT Agents in RAFT Polymerization

The retardation ability of four kinds of carbazyl reversible addition-fragmentation chain transfer （RAFT） agents which were benzyl N-carbazolecarbodithioate （BCBD） , 1-phenylethyl N-carbazolecarbodithioate （PCBD） ,cumyl N-carbazolylcarbodithioate （CCBD） and 2-cyanoprop-2-yl N-carbazolecarbodithioate （CYCBD） was compared in the RAFT polymerization of styrene, ethyl acrylate and methyl methacrylate by dilatometry polymerizing. The effect of the quantity of RAFT agents, different monomers and the polymerization temperature on retardation ability was investigated. The results show that the carbazyl RAFT agents present evident retardation ability in RAFT polymerization and the retardation abilty of RAFT agents depends strongly on their chemical structures. Furthermore, under the same condition, the retardation ability of above four RAFT agents decreases in the order： CCBD〉 PCBD〉 BCBD〉CYCBD.