活性阴离子聚合定量“开-关”聚合机理研究

Quantitatively “Locked-Unlocked” Mechanism in Living Anionic Polymerization

在链增长聚合过程中,有效控制聚合活性中心的"开"、"关"能够对特定结构和功能的聚合物合成实现"定制裁剪"。当活性中心能够进行"锁闭(Locked)"和"解锁(Unlocked)"状态便捷可控的转换,即可在特定位置实现特定单元的插入。近期,大连理工大学马红卫等在活性阴离子聚合领域开展了活性中心定量"开-关"聚合机理研究。基于烷氧硅基DPE(DPE-Si(O-iPr)_3,DPE:1,1-二苯基乙烯)以及醇钠(NaODP)来实现活性阴离子聚合体系活性中心的定量"开-关",在活性阴离子聚合机理方面取得的这一进展能够为阴离子聚合理论研究带来新的发展,同时也为高分子链结构的精密调控提供了更广阔的前景。

The control of locked and unlocked states in chain-growth polymerization has wonderful potential for the precisely synthetic polymers with specific structures or functions.Because a large number of living centers exist during chain propagation,if all or portion of them can be controllably switched between the locked and unlocked states,the chain propagation can either insert specific monomer units or block structures at specific sites.Ma’s group at Dalian University of Technology reported an intriguing advance in living anionic polymerization(LAP)by a“locked-unlocked”mechanism in which the living anionic species can be quantitatively locked by end-capping with 1-(tri-isopropoxymethylsilylphenyl)-1-phenylethylene(DPE-Si(O-iPr)3)and can be unlocked by adding the key,sodium 2,3-dimethylpentan-3-olate(NaODP).This intriguing mechanistic finding of LAP reactions is expected to supplement the existing knowledge and facilitate the tailoring of specific structures for these polymerizations.