In situ synthesis of fluorinated diblock copolymer nanoparticles via RAFT dispersion polymerization in supercritical carbon dioxide

摘要

Synthesis of the fluorinated diblock copolymer nanoparticles of poly(dodecafiuoroheptyl methacrylate)-b-poly(methyl methacrylate) (PDFMA-b-PMMA) by RAFT dispersion polymerization is performed in supercritical carbon dioxide. Fluorinated macro-RAFT agents were first prepared via RAFT solution polymerization and characterized by NMR and GPC. The RAFT-terminated poly(dodecafluoroheptyl methacrylate) (PDFMA) homopolymers actually act as in situ stabilizer for the subsequent synthesis of the PDFMA-b-PMMA block copolymer nanoparticles by RAFT dispersion polymerization while exhibiting good control on the well defined spherical particles formation. SEM images show that the average size of these synthesized diblock copolymer nanoparticles was 425 nm with a narrow size distribution (1.13), which are close to the literature data for conventional MMA dispersion polymerization with a fluorinated CCVphilic stabilizer in ScCO2.