RAFT 分散聚合诱导自组装制备 PDMAs-PSx 嵌段共聚物纳米颗粒

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.

Preparation of PDMAs-PSx block copolymer nanoparticles by RAFT dispersion PISA

Reversible addition-fragmentation-chain transfer (RAFT) polymerization-induced 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 $^\circ$C. 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.