Amphiphilic block copolymers capable of self-assembly into various nanoscale structures are attractive candidates for applications in sensing, controlled delivery and as nanoreactors. We report on synthesis of temperature-responsive copolymers of water-soluble poly(vinylcaprolactam) (PVCL) and poly(vinylpyrrolidone) (PVPON) blocks and their assembly into temperature-sensitive nanostructures in aqueous solutions. The PVCL-block-PVON copolymers were synthesized by RAFT polymerization. The copolymers became amphiphilic upon increase in solution temperature due to the reversible coil-to-globule transition of PVCL blocks. The LCST of the diblock copolymers ranged from 35 to 43�C depending on PVCL molecular weight and the ratio of PVCL to PVPON lengths. Remarkably, the PVCL-block-PVPON copolymers underwent temperature-induced self-assembly into nanostructures of 70 nm to 200 nm in size with hydrophobic PVCL blocks shielded by hydrophilic PVPON. The effects of the block lengths ratio, PVCL molecular weight, and the copolymer concentration on the temperature-triggered formation and disassembly of the nanostructures were examined by NMR, light scattering, and TEM. 

Synthesis and self-assembly of thermosensitive poly (N-vinylcaprolactam)-b-poly (N-vinyl-2-pyrrolidone) diblock copolymers

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.