环己烷-水-十二烷基硫酸钠-添加剂O/W乳状液的分层速率和稳定性

The Creaming Rate and Stability of Cyclohexane/Water/SDS/Additives Oil/Water Emulsions

通过新制备的电导电极 ,测定了不同组成的环己烷 -水 -十二烷基硫酸钠 (SDS)乳状液在富水相不同时间的电导率。为了定量讨论乳状液的稳定性 ,提出了增比电导率的概念 ,根据富水相增比电导率时间曲线 ,求得了乳状液的初始分层速率常数。同时进一步讨论了不同添加剂 (正丁醇和聚乙二醇 )对乳状液初始分层速率的影响。结果表明 ,用初始分层速率常数的大小来衡量乳状液的稳定性 ,是简明直观。

The specific conductivity of emulsions composed of cyclohexane/water/SDS/additives in water-rich phase were measured at different time by a pair of electrodes.The incremental ratio of specific conductivity,κ r=(κ t-κ 0)/κ 0,was proposed to discuss the stability of emulsions.According to the relationship between the incremental ratio of specific conductivity and time in water-rich phase,the initial creaming rate constants of emulsions were obtained by employing the equation k e0 =( d κ r/d t ) t →0 ,and the effects of additives( n -butanol and polyethylene glycol)on the initial creaming rate constants of the emulsions were discussed in detail.It is evident from the results that the stability of emulsions can be analyzed simply and reliably by using the initial creaming rate constants of the emulsions. [