支链化延展型阴离子表面活性剂在聚甲基丙烯酸甲酯表面的吸附行为  

Adsorption behavior of branched extended anionic surfactants on polymethylmethacrylate surface

作　　者：赵濉[1] 江琴 杜悦春 张磊[1] 王明霞[3] 张路[1] ZHAO Sui;JIANG Qin;DU Yue-chun;ZHANG Lei;WANG Ming-xia;ZHANG Lu(Key Laboratory of Photochemical Conversion and Optoelectronic Materials,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;School of Chemical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;School of Material Science and Engineering,Tiangong University,Tianjin 300387,China)

机构地区：[1]中国科学院理化技术研究所光化学转换与功能材料重点实验室,北京100190 [2]中国科学院大学化学科学学院,北京100049 [3]天津工业大学材料科学与工程学院,天津300387

出　　处：《天津工业大学学报》2022年第1期39-46,共8页Journal of Tiangong University

基　　金：国家重点研发计划项目(2019YFA0708700)。

摘　　要：为研究不同结构的表面活性剂在固体表面的吸附性能,利用座滴法研究支链化延展型阴离子表面活性剂十二烷基(聚氧异丙烯)8硫酸盐(G-C_(12)PO_(8)S)和十六烷基(聚氧异丙烯)8硫酸盐(G-C_(16)PO_(8)S)在聚甲基丙烯酸甲酯(PMMA)表面的润湿性,考察延展型表面活性剂的支链化程度对吸附行为的影响,并讨论粘附张力、固液界面张力及粘附功的变化规律。结果表明:当浓度低于临界胶束浓度(cmc)时,PO基团的特殊性质增强了表面活性剂分子与PMMA表面的极性相互作用,表面活性剂通过极性基团吸附在PMMA表面,疏水尾链指向溶液,导致PMMA表面被疏水化;当浓度高于cmc时,表面活性剂分子倾向于在PMMA-溶液界面形成聚集体,亲水头指向溶液,导致固体表面被亲水改性;在疏水改性时,表面活性剂分子的支链化程度起主导作用;而在亲水改性时,空间阻碍起主导作用。In order to study the adsorption mechanisms of surfactants with different structures,the wettability of branched extended anionic surfactants sodium dodecyl(polyoxyisopropene)8 sulfate(G-C_(12)PO_(8)S)and sodium hexadecyl(polyoxyisopropene)8 sulfate(G-C_(16)PO_(8)S)on the surface of polymethylmethacrylate(PMMA)was investigated by sessile drop analysis.The effect of the branched chains for the extended surfactants on the adsorption behavior was explored.Meanwhile,the variation of the adhesional tension,solid-liquid interfacial tension,and adhesion work were discussed.The results indicate that the special properties of the PO group enhances the polar interaction between the surfactant molecules and the PMMA surface before critical micelle concentration(cmc).The surfactants adsorb at the PMMA surface via polar groups with hydrophobic chains towards water,thus the PMMA surface is hydrophobized.After cmc,the surfactants tend to form aggregations at the PMMA-liquid interface.At this stage,the hydrophilic heads of the surfactant molecules point to water,so the solid surface is modified to be hydrophilic.In the stage of hydrophobic modification,the branched degree of surfactant molecules plays a dominant role.However,steric hindrance plays a dominant role in the stage of hydrophilic modification.

关 键 词：支链化 延展型阴离子表面活性剂 聚甲基丙烯酸甲酯 接触角 吸附 

分 类 号：O647.311[理学—物理化学]