N-异丙基丙烯酰胺共聚物的温度敏感性研究

Temperatre-responsive Properties of Copolymers Having PNIPAAm Segment

通过自由基聚合合成了 N-异丙基丙烯酰胺和甲基丙烯酸甲酯及甲基丙烯酸的共聚物。研究了甲基丙烯酸甲酯和甲基丙烯酸的加入对聚 N-异丙烯酰胺温度敏感性的影响 ,并考察了溶液中盐浓度和 p

The copolymers,Poly(N-isopropylacrylamide-co-methyl methacrylate),Poly(N-isopropylacryamide-co-methacrylic acid) and poly(N-isopropylacrylanide-co-methylmethacrylate-co-methacrylic acid),were synthesized by free-radical copolymerization using AIBN as an initiator,The molecular Weights of the copolymers were measured by GPC.The lower critical solution temperature(LCST)of copolymers measured by UV/Vis spectrophotometer at 400nm were lower than LCST of Poly(N-Isopropylacrylamide)based on MMA and MAA segments which were lower hydrophilic than NIPAAm segment.The LCST of copolymers were lowered linearly when salt concentrations were increased in the solution.The LCST of Poly(NIPAAm-co-MAA) and Poly(NIPAAm-co-MMA-co-MAA)were dependent on pH of their solution at high pH range.It means that the two copolymers are Temperature-responsive and pH-responsive ones.