丙烯腈-N-异丙基丙烯酰胺接枝共聚物的合成及其对聚丙烯腈分离膜的改性  

SYNTHESIS OF ACRYLONITRILE-N-ISOPROPYLACRYLAMIDE GRAFT COPOLYMERS FOR THE PREPARATION OF THERMAL RESPONSIVE POLYACRYLONITRILE MEMBRANAES

作　　者：费正东[1,2] 万灵书[1] 钟明强[2] 徐志康[1] 

机构地区：[1]浙江大学高分子科学与工程学系高分子合成与功能构造教育部重点实验,杭州310027 [2]浙江工业大学化材学院,杭州310014

出　　处：《高分子学报》2012年第4期404-409,共6页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21174124)资助项目

摘　　要：以巯基乙胺盐酸盐(AESH)为链转移剂、2,2'-偶氮二异丁腈为引发剂,合成了具有端氨基的聚(N-异丙基丙烯酰胺)(PNIPAAm);与甲基丙烯酰氯反应,得到可聚合的PNIPAAm大分子单体;进而与丙烯腈共聚,合成了丙烯腈-N-异丙基丙烯酰胺接枝共聚物(P(AN-g-NIPAAm)).基于浸没沉淀相转化法制备了聚丙烯腈/P(AN-g-NIPAAm)共混膜.红外及核磁分析表明,通过调控AESH的浓度可制备得到不同链长的PNIPAAm大分子单体;用激光光散射进一步测定了共聚物的重均分子量;采用鼓泡接触角及浊度测定考察了共聚物的温敏特性;XPS结果证实PNIPAAm链在膜表面发生富集;纯水压滤实验发现所制备的分离膜40℃(高于PNIPAAm的LCST)时的水通量是25℃(低于PNIPAAm的LCST)时的近2倍,具有较明显的温敏性.PNIPAAm with terminal amino groups was synthesized using 2-aminoethanethiol hydrochloride （AESH） as a chain transfer agent. It was then reacted with methacryloyl chloride to result in macromer,vinly PNIPAAm. A graft copolymer, P（AN-g-NIPAAm） was synthesized through the copolymerization of acrylonitrile （AN） and vinyl PNIPAAm. Using this graft eopolymer as an additive, thermal responsive PAN-based membranes were prepared by the immersion precipitation phase inversion method （IPPI）. Results from FTIR and NMR indicate that the molecular weight of PNIPAAm can be effectively modulated by changing the concentration of AESH. Then,the weight average molecular weight （Mw ） was measured by laser scattering. Results of captive bubble contact angle measurements and turbidity analysis show that the graft copolymers are still thermally responsive,which is more remarkable with higher PNIPAAm content. XPS analysis proves that the PNIPAAm graft chains are enriched at the membrane surface and pore surface during the course of IPPI because of the hydrophilicity of PNIPAAm. Pure water flux at 40~C （above the LCST of PNIPAAm） is almost twice as that at 25℃ （below the LCST of PNIPAAm） ,which is due to the conformation change of PNIPAAm chains. All these results demonstrate the synthesized graft copolymers are effective additives for the preparation of thermal responsive PAN membranes.

关 键 词：聚丙烯腈 聚(N-异丙基丙烯酰胺) 大分子单体 共混改性 温敏性分离膜 

分 类 号：O631.3[理学—高分子化学]