阳离子型共聚物AM/DMBAC疏水微嵌段结构的分析  

STUDIES ON MICROBLOCK STRUCTURE OF AM/DMBAC CATIONIC COPOLYMERS

作　　者：王桂霞[1,2] 李万刚[1,2] 张玉玺[1] 李振泉[3] 宋新旺[3] 曹绪龙[3] 吴飞鹏[1] 

机构地区：[1]中国科学院理化技术研究所新型功能聚合物材料研究组,北京100190 [2]中国科学院研究生院,北京100049 [3]中石化胜利油田分公司地质科学研究院,东营257015

出　　处：《高分子学报》2010年第4期435-441,共7页Acta Polymerica Sinica

摘　　要：利用表面张力法对甲基丙烯酰氧乙基二甲基苄基氯化铵(简称DMBAC)在水溶液中的表面活性进行了测试并确定了其CMC值.研究了丙烯酰胺(AM)和DMBAC在水溶液中的共聚合反应行为,测定了AM与DMBAC共聚反应的竞聚率;IR,1H-NMR对共聚物的结构进行了表征;13C-NMR和DSC分析了单体DMBAC浓度对共聚产物微结构的影响;芘作为荧光探针测定了共聚物水溶液的疏水缔合性质.实验结果表明当共聚单体DMBAC浓度大于CMC时DMBAC倾向于均聚,DMBAC在共聚产物主链上呈微嵌段的形式分布.当共聚单体DMBAC浓度小于CMC时,DMBAC与AM倾向于无规共聚.The surface activity of cationic DMBAC （ dimethyl methacryloyloxyethyl benzyl ammonium chloride） was revealed by measuring surface tension and estimating of critical micelle concentration （ CMC）. The copolymerization of acrylamide （ AM） and DMBAC was studied in aqueous solution at above and below CMC of DMBAC,respectively. The reactivity ratios r1 and r2 were determined by the Fineman-Ross method. IR and 1H-NMR spectra afford information about polymer structure. The compositions of copolymers were calculated by UV spectrophotometer. The intrinsic viscosity values of the copolymers were measured by the Ubbelohde-type Viscometer. Molecular weight （ Mw ） and polydispersity index （ PDI） of the copolymers were measured by gel permeation chromatography （GPC）. The effect of DMBAC concentration on the microstructure of the copolymers was analyzed by 13C-NMR and DSC spectra. The property of hydrophobic association of the copolymers was characterized by using pyrene fluorescence probe technique. The experimental results of copolymerization showed that the reactivity ratios of monomers were different at above and below CMC of DMBAC,r1（AM） = 0. 65,r2（DMBAC） = 1. 41 and r1（AM） = 0. 74,r2 （ DMBAC） = 0. 91,respectively. These results suggested that DMBAC monomers may distribute in a microblock sequence in the copolymer chain at above CMC of DMBAC,and in a random sequence at below CMC of DMBAC. The structures of copolymers were proved again by 13 C-NMR and DSC spectra. The copolymer CP-1 with microblock sequences showed stronger hydrophobically associating than the copolymer CP-2 with random sequences.

关 键 词：阳离子型共聚物 竞聚率 疏水缔合作用 微嵌段 序列结构 

分 类 号：O631.3[理学—高分子化学]