摘要
本文研究的微乳液，以十六烷基三甲基溴化铵（ＣＴＡＢ）为表面活性剂，正戊醇（ｎ－Ｃ５Ｈ１１ＯＨ）为助表面活性剂，八甲基环四硅氧烷（Ｄ４）为油相及水四组分组成。从微乳液拟三组分相图出发，确定微乳液区域，然后从接近相图油顶点的某一组成微乳液出发，滴加Ｄ４至微乳液破坏，再滴加醇恢复微乳液。如此连续八次，得到一系列微乳液形成的ｎａ／ｎｓ，ｎｏ／ｎｓ，（ｎａ、ｎｓ、ｎｏ分别为相应微乳体液体系中醇，表面活性剂和油的摩尔数），用计算机关联得到相应直线的斜率Ｋ和截距Ｉ，从ΔＧ０→ｉ＝－ＲＴｌｎＩ（Ｋ＋１）Ｋ（Ｉ＋１）公式，计算上述体系中醇从油相到微乳液液滴界面的标准自由能ΔＧ０→ｉ。另外，从ΔＧ０→ｉ随温度的变化，可得到该过程的ΔＨ０→ｉ和ΔＳ０→ｉ。本文对其结果进行理论分析和讨论，这些结果在制备有机硅微乳液、有机硅微乳聚合和化妆品生产中具有指导意义。
The microemulsions studied in this paper consist of surfactant cetyltrimethylammonium bromide(CTAB),axiliary surfactant n-pentanol,oil phase octamethyl-cyclotetrasiloxane (D 4) and water. From the pseudo-tricomponent phase diagram of the microemulsion the region of the microemulsion was determined. The microemulsion was broken by dropping in D 4 and restored by dropping in alcohol,and this process was repeated for 8 times,resulting in plots of n a/n s vs n o/n s of the microemulsion,and then K and I of the related straight line were calculateed by the use of computer.The standard free energy ΔG 0→i of the transfer from the continuous oil phase to the interfacial region of the microemulsion was calculated by ΔG 0→i =-RTlnI(K+1)K(I+1) and the ΔH 0→i ,and ΔS 0→i ,during the process were also obtained based on the relation of ΔG 0→i ,with the temperature.The result of the studies was analyzed and discussed theoretically,and it is of guiding significance to the preparation of silicone microemulsion,to the polymerization of silicone emulsion and to the production of cosmetics.
