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以钴Ⅱ肟氟化硼络合物(CoBF)为催化剂,2,2′-偶氮二异丁腈(AIBN)为引发剂,实现了甲基丙烯酸甲酯(MMA)与γ-甲基丙烯酰氧基丙基三甲氧基硅烷(MPS)在60℃甲苯体系中的催化链转移聚合(catalytic chaintransfer polymerization,CCTP),制备出末端含有双键的共聚物.利用核磁共振证明了其末端双键的存在,并通过热重分析证明CCTP产物与自由基聚合产物的结构区别.用凝胶渗透色谱(GPC)对7种单体组成下不同催化剂CoBF用量的聚合产物进行分子量表征,结果表明以催化链转移聚合合成的共聚物具有分子量低及分子量分布较窄,且聚合物的分子量随着催化剂CoBF的增加呈明显下降趋势.又分别采用了基于DPn(数均聚合度)、DPw(重均聚合度)的Mayo方程和基于ΛP、ΛH的链长分布方程计算出催化剂的表观链转移常数,发现基于DPw的Mayo方程和基于ΛP的链长分布方程的计算结果最为接近.并通过对共聚体系中不同单体组成的研究发现,催化剂表观链转移常数随着单体组成中MPS的增加而增加.
Using cobalt Ⅱ oxime boron fluoride complex (CoBF) as catalyst and 2,2’-azobisisobutyronitrile (AIBN) as initiator, the reaction of methyl methacrylate (MMA) with γ-methyl propylene Acyloxypropyltrimethoxysilane (MPS) was prepared by catalytic chaintransfer polymerization (CCTP) in a toluene system at 60 ° C to prepare a copolymer containing a double bond at the end.It was proved by nuclear magnetic resonance that its terminal double bond And the difference of structure between CCTP product and free radical polymerization product was proved by TG.The molecular weight characterization of the polymerization products of different catalyst CoBF with gel permeation chromatography (GPC) The copolymers synthesized by chain transfer polymerization have low molecular weight and narrow molecular weight distribution, and the molecular weight of the polymer tends to decrease with the increase of the catalyst CoBF. The copolymers based on DPn (number average degree of polymerization), DPw Degree) and the chain length distribution equation based on ΛP, ΛH calculated the apparent chain transfer constant of the catalyst and found that the calculation results of the Mayo equation based on DPw and the chain length distribution equation based on ΛP closest to. And through the copolymer Study of different monomer composition found that the apparent chain transfer constant of the catalyst with the increase of MPS monomer composition increases.