通过动态流变、幂律模型、动/静态激光光散射以及荧光光谱考察了丙烯酸十八酯（ODA）、丙烯酰胺（AM）、2-丙烯酰胺基-2-甲基丙磺酸（AMPS）经超声辅助（Ultrasonic assist）自由基共聚制得的疏水缔合聚丙烯酰胺（UHAPAM）的动态流变性及其与阴阳离子型表面活性剂（十二烷基硫酸钠（SDS）和十六烷基三甲基溴化铵（CTAB））之间相互作用关系。结果表明,这种假塑性流体的临界聚集浓度（CAC）为0.27%。当UHAPAM水溶液浓度高于CAC时,SDS影响分子间疏水缔合,使水溶液表观粘度下降;CTAB反而改善疏水缔合性,使表观粘度明显增加,但增粘效果越来越缓和。表面活性剂均使溶液触变性降低。同时,形状因子（〈Rg〉/〈Rh〉）在SDS-UHAPAM体系里随SDS浓度的增加而增加,聚合物分子线团变得相对舒展;而在CTAB-UHAPAM体系里则随CTAB浓度增加而出现最低值,聚合物分子链段历经一个卷缩然后舒展的过程。在SDS和CTAB胶束中加入UHA-PAM,SDS聚集数先减小后增大,而CTAB聚集数则持续增加。%Hydrophobically associating polyacrylamide(UHAPAM) was prepared by the reaction of octadecyl acrylate(ODA),acrylamide(AM) and 2-acrylamido-2-methyl propane sulfonic acid(AMPS) through ultrasonic assisted polymerization.The dynamic rheology property of UHAPAM and interactions between ionic surfactants(odium dodecyl sulfate(SDS) and hexadecyl trimethyl ammonium bromide(CTAB)) and UHAPAM were studied by dynamic rheology,power-law model,static/dynamic light scattering and fluorometry.The results showed that the critical association concentration(CAC) of UHAPAM aqueous solution was determined as approximately 0.27% and when the UHAPAM solution concentration was higher than CAC,SDS was adverse to inter-molecular association,which led to reduced apparent viscosity;CTAB improved the hydrophobically associating properties on the contrary,which significantly resulted in increased apparent viscosity,but as CTAB continued to increase,the thickening effect deteriorated.Both the surfactants reduced thixotropy of UHAPAM solution.At the same time,the shape factor(〈Rg〉/〈Rh〉) increased all the time in SDS-UHAPAM system as SDS concentration increased,which reflected the relative stretch of the polymer chains;but it appeared a minimum value in CTAB-UHAPAM system with CTAB concentration increasing,which reflected the polymer chain transformed from curl to stretch.Along with UHAPAM concentration increasing,aggregation number(N) of SDS micelles increased after first reducing,and that of CTAB micelles increased continuously.
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