物理化学学报 >> 2009, Vol. 25 >> Issue (05): 911-914.doi: 10.3866/PKU.WHXB20090510

研究论文 上一篇    下一篇

DMA/AOT摩尔比对非水微乳体系临界现象的影响

蔡红兰 安学勤 朱银燕 吕辉鸿 沈伟国   

  1. 鲁东大学化学与材料科学学院, 烟台 264025; 华东理工大学化学与分子工程学院, 上海 200237; 江苏省生物功能材料重点实验室, 南京 210097
  • 收稿日期:2008-12-10 修回日期:2009-01-19 发布日期:2009-05-04
  • 通讯作者: 安学勤 E-mail:anxueqin@163.com

Effects of DMA/AOT Molar Ratio on Critical Behavior of Nonaqueous Microemulsion

CAI Hong-Lan, AN Xue-Qin, ZHU Yin-Yan, LV Hui-Hong, SHEN Wei-Guo   

  1. School of Chemistry and Materials Science, Ludong University, Yantai 264025, Shandong Province, P. R. China; School of Chemistry and Molecular Engineering, East China University of Science &Technology, Shanghai 200237, P. R. China; Jiangsu Key Laboratory of Biofunctional Materials, Nanjing 210097, P. R. China
  • Received:2008-12-10 Revised:2009-01-19 Published:2009-05-04
  • Contact: AN Xue-Qin E-mail:anxueqin@163.com

摘要:

采用折射率法测定了非水微乳体系{N,N-二甲基乙酰胺(DMA)/二(2-乙基己基)琥珀酸酯磺酸钠(AOT)/正辛烷}在不同DMA与AOT摩尔比ωs时的温度-折射率(T-n)共存曲线, 并根据曲线推导出临界指数β和指前因子B. 结果表明, 临界组成φc(即DMA和AOT的体积之和在总体积中所占的分数)随ωs的增加而降低, 而临界温度Tc随ωs增加而增大; 临界指数β与ωs无关, 其数值趋近于Fisher重整化理论值(0.365); 与体系有关的指前因子B随ωs的增加而增大.

关键词: 微乳液, 临界现象, 共存曲线, AOT

Abstract:

Coexistence curves of (T-n) (T and n are temperature and refractive index, respectively) for {N,N-dimethylaccetamide(DMA)/sodiumbis(2-ethylhexyl)sulfosuccinate(AOT)/n-octane} nonaqueousmicroemulsion systems with various molar ratios ωs of DMA to AOT have been determined by the measurement of refractive index. Critical exponents (β) and critical amplitudes (B) were deduced fromcoexistence curves of (T-n). Results show that the critical volume fraction φc {i.e. φ=(VAOT+VDMA)/(VAOT+VDMA+Vn-octane)} increases as ωs decreases, but the critical temperature Tc increases with the increase in ωs. Value of the critical exponent βis independent of ωs and approaches 0.365, which is consistentwith the Fisher-renormalization group theory. System-dependence amplitudes (B) increase almost linearly with the increase in ωs.

Key words: Microemulsion, Critical phenomena, Coexistence curve, AOT

MSC2000: 

  • O648