水溶性RAFT链转移剂的制备及应用进展

可逆加成-断裂链转移(reversible addition-fragmentation chain transfer,RAFT)聚合是一种有效的可控/活性自由基聚合方法,在功能型高分子的制备中有广泛的应用,RAFT聚合的关键就在于选择合适的RAFT链转移剂。基于环保无害的要求,水溶性RAFT链转移剂的制备就至关重要。本文介绍了RAFT聚合的机理,综述了水溶性RAFT链转移剂的制备及应用进展,探讨出RAFT链转移剂水溶性的作用机理,一方面是极性基团的作用,另一方面是离子键氢键等的作用,这对水溶性RAFT链转移剂的制备有一定的启发。大分子RAFT链转移剂分子中常含有亲水基团和疏水基团,具有一定的分散作用,在水相条件下不仅可以通过扩链反应制备窄分子量分布的嵌段共聚物,还可以制备出微纳米凝胶。

Progress in Preparation and Application of Water-soluble RAFT Agents

Reversible addition-fragmentation chain transfer polymerization(RAFT)is an effective controlled/living free radical polymerization method.It is widely used in the preparation of functional polymers.The key to RAFT polymerization is to select the appropriate RAFT agent.The preparation of water-soluble RAFT agents is critical based on environmentally sound and non-hazardous requirements.The paper introduces the mechanism of RAFT polymerization and summarizes the preparation and application of water-soluble RAFT agents.The mechanism of water solubility of RAFT chain transfer agent was discussed.On the one hand,the role of polar group,on the other hand,the role of ionic bond hydrogen bond etc.that has certain enlightenment for the preparation of water-soluble RAFT agent.The macro-RAFT agent often contains hydrophilic groups and hydrophobic groups with dispersion effect.Under the aqueous phase condition,not only a narrow molecular weight distribution block copolymer can be prepared by chain extension reaction,but also micro/nano-gel can be prepared.