化工学报2013，Vol.64Issue(8)：2947-2955,9.DOI:10.3969/j.issn.0438-1157.2013.08.035
结合吸附模型预测油水液滴的界面流变性质
Interfacial rheological properties of oil/water droplet with dynamic adsorption models
摘要
Abstract
The adsorption of interfacial active molecules on oil-water interface will directly affect its interfacial properties,such as interfacial tension,interfacial dilatational rheology,which influences the stability of oil/water emulsions.The interfacial properties could be quantitatively analyzed by introducing a proper adsorption model.In this work,Span 80 was selected as the surface active component and added in a mineral oil-deionized water system.The interfacial tension and dilatational rheology were measured below and above the critical micelle concentration (CMC,0.45 mmol · L-1 in this work).It was found that the interfacial dilatational modulus increased first and then decreased as the concentration of Span 80 continued to increase.Since the pure diffusion controlled model was insufficient to accurately describe the relaxation behavior,the relaxation model from Lucassen-van den Tempel was combined with dynamic adsorption models,such as Langmuir,Frumkin,reorientation,and rigorous reorientation model.The results showed that a combination with rigorous reorientation model accurately predicted the oil/water interfacial tension and indicated the influence of surfactant,frequency on interfacial dilatational modulus properly.Interfacial tension and dilatational modulus were measured with the spinning drop method.During the measurement,an oil drop of 2.5μl was injected into the capillary filled with deionized water.The capillary was rotated at 10000 r · min-1,and the temperature was maintained with an air bath circulation system.The image profile of the droplet was recorded with a video camera at 4 fps.Interfacial tension was calculated from the geometric contour of the drop with the Young-Laplace equation,while interfacial dilatational modulus was determined from the difference of interfacial tension and interfacial area.Interfacial dilatational modulus was determined after equilibrium adsorption of Span 80 molecules.关键词
油水乳状液/界面张力/界面扩张流变/吸附模型/严格重排模型Key words
oil/water emulsion/ interfacial tension/ interfacial dilatational rheology/ dynamic adsorption model/ rigorous reorientation model分类
化学化工引用本文复制引用
王玮,李楷,郝帅,宫敬..结合吸附模型预测油水液滴的界面流变性质[J].化工学报,2013,64(8):2947-2955,9.基金项目
国家自然科学基金项目(51104167) （51104167）
优博论文作者资助项目(201254) （201254）
国家重大科技专项(2011ZX05026-004-03) （2011ZX05026-004-03）
教育部新世纪人才基金项目(NCET-12-0969) （NCET-12-0969）
中国石油大学(北京)科研基金联合资助项目(BJ-2011-02).supported by the National Natural Science Foundation of China (51104167),the Foundation for the Author of National Excellent Doctoral Dissertation of China (201254),the National Science & Technology Specific Program of China (2011ZX05026-004-03),the Program for New Century Excellent Talents in University (NCET-12-0969) and the Science Foundation of China University of Petroleum-Beijing (BJ-2011-02). （北京）
