论文部分内容阅读
耦合先臂法(“arm first”)和可逆加成-断裂链转移(RAFT)自由基聚合制备以温度响应性聚(聚乙二醇甲醚丙烯酸酯-co-2-(2-乙氧基乙氧基)乙基丙烯酸酯)(POD)和p H响应性聚丙烯酸二甲氨基乙酯(PDMAEA)为臂,含二硫键的N,N’-双丙烯酰胱胺(BAC)为核的杂臂星型聚合物(MAS).采用傅里叶红外光谱(FTIR)、核磁共振氢谱(1H-NMR)和凝胶渗透色谱(GPC)对聚合物的结构、相对分子质量及分子量分布进行了表征.结果表明,该法能有效控制星型聚合物的合成(分子量分布指数PDI<1.3).采用紫外可见吸收光谱法(UV-Vis)、动态光散射(DLS)考察了MAS在水中的相变行为.结果表明,随着臂PDMAEA含量的增加,星型聚合物的LCST增大.当臂POD与PDMAEA的摩尔投料比为5∶5时,聚合物浓度为1 mg/m L时其在纯水中的LCST为38.2℃.
(PEG-methyl-acrylate-co-2- (2-ethyl-2-methylethyl) acrylate) was prepared by radical polymerization using the “arm first” method and reversible addition-fragmentation chain transfer (RAFT) (POD) and p H-responsive dimethylaminoethyl polyacrylate (PDMAEA) as arms, disulfide-bonded N, N’-bisacrylamido cystamine (BAC) (MAS) .FTIR, 1H-NMR and gel permeation chromatography (GPC) were used to characterize the structure, relative molecular mass, (Molecular weight distribution index PDI <1.3) by UV-visible spectroscopy and dynamic light scattering (DLS) Phase transition behavior in water.The results showed that the LCST of the star polymer increased with increasing arm PDMAEA content.When the molar ratio of POD to PDMAEA was 5: 5, the polymer concentration was 1 mg / m Its LCST in pure water is 38.2 ℃.