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本文从聚合机理和反应动力学两方面综述了近年来六甲基环三硅氧烷(D3)的阴离子开环聚合研究进展。早期Frye等提出在非极性的碳氢溶剂中会形成引发剂的三种加成物质,在不加入促进剂的情况下不会进行D3的开环聚合,这一开环聚合机理成为随后D3阴离子开环聚合机理研究的基础,研究者采用MALDI-TOF研究聚合机理得到的结论证实了这一机理的正确性,促进剂、溶剂、引发剂的类型和聚合步骤会改变活性链末端的缔合和解缔合的平衡能力,对D3开环过程中的反咬和再分布副反应有显著影响。D3开环聚合增长速率对单体浓度为一级,不同的促进剂和引发剂会显著改变活性链末端的缔合能力,从而显著影响聚合动力学。
This review summarizes recent progress in the anionic ring-opening polymerization of hexamethylcyclotrisiloxane (D3) from two aspects: polymerization mechanism and reaction kinetics. Early Frye et al proposed that three non-polar hydrocarbon solvents will form an initiator in the three adducts, without the addition of a promoter without the ring-opening polymerization of D3, and this ring-opening polymerization mechanism becomes D3 The mechanism of anionic ring-opening polymerization was studied. The results obtained by investigators using MALDI-TOF to study the polymerization mechanism confirm the correctness of this mechanism. The types of promoters, solvents, initiator types and polymerization steps will change the association of active-chain ends The balance ability of reconciliation has a significant effect on the anti-bite and redistribution side reactions during D3 ring opening. D3 ring-opening polymerization rate of monomer concentration for the first stage, different promoters and initiators will significantly change the activity of the chain end association, which significantly affect the polymerization kinetics.