PAN-b-PHEA的合成与表征

Polymerization and Characterization of PAN-b-PHEA

首先以丙烯腈(AN)为单体、2-溴异丁酸乙酯(EBiB)为引发剂、溴化亚铜(CuBr)以及1,10-菲罗啉为催化体系,经原子转移自由基聚合(ATRP)反应合成聚丙烯腈(PAN),利用质量法测定了引发剂和催化剂用量对AN转换率的影响;然后以2-羟乙基丙烯酸乙酯(HEA)为单体、PAN-Br为大分子引发剂、CuBr和N,N,N′,N″,N″-五甲基二乙烯三胺(PMDETA)为催化体系,合成了PAN-b-PHEA嵌段共聚物。采用红外光谱(FT-IR)、核磁共振谱(1 H-NMR)、元素分析对聚合物的结构进行了表征,并经热重分析考察了PAN-b-PHEA嵌段共聚物的热分解行为。结果表明,当n(AN)/n(EBiB)=100以及n(CuBr)/n(AN)=1%时,AN的ATRP聚合反应呈现一级动力学特征(ln(c0/ct)与时间t的线性相关系数为0.988)。PAN-b-PHEA嵌段共聚物的热分解温度为250°C。

Polyacrylonitrile （PAN） can be polymerized via atom transfer radical polymerization （ATRP） in a controlled way using acrylonitrile（AN） as monomer, ethyl 2-bromoisobutyrate（EBiB） as initiator and CuBr/1,10-phenanthroline as catalytic system. The influence of the dosage of initiator and catalytic system on the conversion of AN was studied by mass method. Then, in the polymerization of PAN-b-PHEA block copolymer by ATRP reaction , 2 hydroxyethyl acrylate （HEA）, PAN-Br, CuBr, N, N, N′, N″, N＂ pentamethyl-diethylenetriamine （PMDETA） were used as the monomer, macroinitiator, catalyst, respectively. The structures of polymers were characterized by FT IR,^1H-NMR and element analysis. And the thermal decomposition behavior of PAN-b-PHEA block copolymer was studied by TG techniques. Results showed that the polymerization of AN by ATRP was first-order reaction when n（AN）/n（EBiB）= 100, n（CuBr）/ n（AN）=1%（the linearly dependent coefficient of ln（co/ct） vs t was 0. 988）. The thermal decomposition temperature of PAN b-PHEA block copolymer was 250 ℃.