聚(酰胺-co-醚)大分子单体的一步法合成及其接枝共聚

One-pot synthesis of poly(amide-co-ether)macromonomer and its graft copolymerization

大分子单体法是制备接枝共聚物的重要方法,但是一步法合成结构丰富的杂链大分子单体极具挑战。为此,文章以N-羟乙基丙烯酰胺(HEAA)为单体,通过氧迈克尔加聚反应一步法制备了端双键聚(酰胺-co-醚)大分子单体(PHEAA),并将其与甲基丙烯酸甲酯(MMA)共聚得到接枝共聚物P(HEAA-g-MMA)。用核磁(NMR)、凝胶渗透色谱(GPC)和差示扫描量热仪(DSC)对大分子单体和聚合物的结构和性能进行了表征。结果表明,HEAA可在室温下通过氧迈克尔加聚反应一步生成主链含酰胺和醚键的大分子单体。单体HEAA的转化率接近100%,且不存在乙烯基加成等副反应。将制备的大分子单体与MMA进行自由基共聚,成功得到了接枝共聚物。接枝共聚物分子质量为26700 g/mol,分子质量分布为1.58,其玻璃化转变温度为66.3℃。

Graft copolymer can be synthesized by the copolymerization of macromonomer and co-monomer.However,the synthesis of vinyl-terminal macromonomer with hybrid backbone by a simple route was rather difficult.Here,N-hydroxyethyl acrylamide(HEAA)was employed as a monomer to prepare vinyl-terminal macromonomer through oxa-Michael polyaddition.The resulted macromonomer composed from amide and ether groups in the backbone was then copolymerized with methyl methacrylate(MMA)forming a graft copolymer.The structures and properties of macromonomers and corresponding graft copolymers were analyzed by nuclear magnetic resonance spectroscopy(NMR),gel permeation chromatography(GPC)and differential scanning calorimetry(DSC).The results showed that poly(amide-co-ether)macromonomers could be successfully prepared by the oxa-Michael polyaddition of HEAA.The conversion of HEAA was close to 100%.No vinyl addition reaction was observed during the polymerization.The molecular weight of the synthesized graft copolymer was 26700 g/mol with a polydispersity index of 1.58 and the glass transition temptation of 66.3℃.