统计结构含氟丙烯酸酯共聚物的合成与表征

本文对含氟丙烯酸酯(FMA)与甲基丙烯酸丁酯(BMA)的RAFT细乳液共聚合及动力学进行了研究, 计算得到了FMA与BMA的竞聚率并制备出具有统计结构的含氟共聚物乳液.

Synthesis and Characterization of Statistical Fluorinated Copolymers via RAFT Miniemulsion Polymerization

Reversible addition fragmentation chain transfer(RAFT) mediated miniemulsion copolymerizations of butyl methacrylate with fluoroacrylate were carried out at 70 ℃ with potassium persulphate as initiator, and the kinetics of copolymerizations were investigated. Copolymer compositions at low conversion levels were determined by 1H NMR spectra techniques. In the presence of RAFT agent 2-cyanoprop-2-yl dithiobenzoate(CPDB), the copolymerization of BMA with FMA in miniemulsion exhibited typical features of a controlled mole-cular weights and narrow polydispersities. The reactivity ratios were evaluated by Kellen-Tudos(K-T) method, which yields the apparent reactivity ratios, rBMA=0.63 and rFMA=0.79. The results show that the monomer FMA with a fluorinated side chain is more reactive than BMA, and the copolymerizations have a tendency to alternate and to produce a higher FMA content in the copolymers. The spontaneous statistical copolymers with soft gradient shapes were obtained using variable initial ratios of BMA and FMA.