RAFT分散聚合诱导自组装制备PDMA_(s)-PS_(x)嵌段共聚物纳米颗粒

Preparation of PDMA_(s)-PS_(x) block copolymer nanoparticles by RAFT dispersion PISA

可逆加成-断裂-链转移(reversible addition-fragmentation-chain transfer,RAFT)聚合诱导自组装(polymerization-induced self-assembly,PISA)是制备具有特定形貌嵌段共聚物纳米颗粒的高效手段.以苯乙烯(styrene,St)为分散聚合的单体,PDMA_(23)和PDMA_(38)为大分子链转移剂(chain transfer agent,CTA),乙醇为溶剂,在70℃下探究了纳米颗粒的形貌随不同聚合度(degree of ploymerizations,DPs)的转变情况.由实验结果可知:以PDMA_(23)为链转移剂,可调控苯乙烯的聚合度,得到球、虫、囊泡、复合囊泡等形貌;以PDMA_(38)为链转移剂,可在较宽的聚合度范围内得到均匀的球形纳米颗粒.

Reversible addition-fragmentation-chain transfer(RAFT)polymerizationinduced self-assembly(PISA)is a versatile and powerful strategy for preparing block copolymer nanoparticles with specific morphologies.Ethanol was used for the RAFT dispersion polymerisation of styrene(St)at 70℃.PDMA_(23)and PDMA_(38)were chosen as macromolecular chain transfer agents(CTAs).The transformation of the morphologies was altered by varying the degree of polymerizations(DPs).The experimental results showed that spheres,worms,vesicles,and compound vesicles were obtained using PDMA_(23)as the CTA.However,only well-distributed spherical nanoparticles were obtained when PDMA_(38)was employed as the CTA.