接枝聚合物PVA-g-PNIPA的合成

Synthesis of Graft Copolymer PVA-g-PNIPA

采用自由基溶液聚合制备了具有温敏性的 N-异丙基丙烯酸胺的线性均聚物 (PNIPA) .利用活性酰胺与聚乙烯醇 (PVA)中羟基的交换反应将 PNIPA接枝在 PVA链上得到接枝聚合物PVA- g- PNIPA.用化学交联法在 W/ O体系中将 PVA- g- PNIPA制成微球 .结果表明 ,接枝聚合物仍具有温敏性 .接枝聚合物中 PNIPA的含量随 PNIPA/ PVA(投料比 )的增加而增加 。

Linear homopolymer of N isopropylacrylamide has been made with AIBN as initiator and DMF as solvent, and it was thermosensitive.Graft copolymer PVA g PNIPA could be prepared through the reaction of the terminal active amide of PNIPA and the hydroxy group of PVA.Microspheres could be made of graft copolymer PVA g PNIPA with glutaraldehyde as cross link agent in water/oil system.It was found that graft copolymer PVA g PNIPA still had thermosensitivity,and the content of PNIPA in PVA g PNIPA could be controlled by the feed proportion of PNIPA and PVA, and microsphere was made readily but it could be affected by the content of PNIPA.