RAFT聚合诱导自组装法合成聚丙烯酸-b-聚丙烯酸六氟丁酯

Polymerization-induced self-assembly of poly(acrylic acid)-b-poly(hexafluorobutyl acrylate)via RAFT emulsion polymerization

以聚丙烯酸为亲水性大分子RAFT试剂,采用 RAFT聚合诱导自组装法制备了聚丙烯酸-b-聚丙烯酸六氟丁酯.采用1 H-NMR、GPC、FT-IR 对聚合物的结构进行了表征.探讨了反应时间、引发剂与链转移剂的摩尔比以及丙烯酸单体与链转移剂的摩尔比对聚合的影响.研究结果表明,当反应时间为6 h,引发剂与链转移剂的摩尔比为0.20∶1时,丙烯酸单体与链转移剂摩尔比为40∶1,丙烯酸的转化率为90.53%,PAA-RAFT的分子量分布为1.12,聚合反应的可控性好.研究了引发剂用量对丙烯酸六氟丁酯的 RAFT 聚合的影响,结果表明当引发剂用量为1.5%时,聚丙烯酸-b-聚丙烯酸六氟丁酯聚合物乳胶粒的粒径分布最窄.TEM分析表明乳胶粒的粒径为300 nm,具有明显的核壳结构.

The well-defined poly （acrylic acid ）-b-poly （hexafluorobutyl acrylate ）（PAA-b-PHFBA）block copolymer was prepared by using PAA-RAFT as macromolecular RAFT a-gent via polymerization-induced self-assenbly technology.The structures of products were characterized by nuclear magnetic resonance （1 H-NMR）,Gel Permeation Chromatography （GPC）and Fourier transform infrared spectroscopy （FT-IR）.The effects of some synthetic parameters of PAA-RAFT were investigated,such as reaction time,the molar ratio of initia-tor and acrylic acid to the RAFT agent DDMAT.As a result,when the reaction time was 6 h,the molar ratio of initiator to chain transfer agent was 0.2∶1 and the molar ratio of acrylicacid to chain transfer agent was 40∶1 ,RAFT polymerization of acrylic acid monomer can be well controlled with high conversion （90.53%）and a narrow molecular weight distribution （PDI=1.12）.The effect of initiator concentration on the hexafluorobutyl acrylate polymeri-zation was studied.The results showed that the poly（acrylic acid）-poly（hexafluorobutyl ac-rylate）polymer latex particle size had a norrow distribution when the dosage of initiator was 1.5%.TEM analysis showed that the latex particle size had a diameter of about 300 nm and obvious core-shell structure.