摘要
以钠基蒙脱土（Na—MMT）为原料，采用湿法球磨法制备双十二烷基二甲基溴化铵（DDAB）插层的改性蒙脱土（DDA—MMT），并在超声作用下乳化液体石蜡制得O／W型Picketing乳液。通过XRD、TEM、FT—IR、接触角测量仪和Zeta电位及激光粒度仪对DDA—MMT进行了表征。考察了DDA—MMT颗粒质量浓度、水相pH和离子强度对Picketing乳液稳定性的影响。实验结果表明，在球磨机械力作用下DDAB成功插入Na—MMT的片层间，使Na—MMT的平均粒径、Zeta电位和三相接触角分别由910．7nm，-26．8mV和121．7°变为603．8nm，38．3mV和86．9°。与Na—MMT颗粒相比，DDA—MMT颗粒更容易在油／水界面间聚集而具有更好的乳化稳定性。随着DDA—MMT颗粒质量浓度的增大，Picketing乳液液滴粒径减小，乳液体积分数增大，稳定性增强。当水相pH=6．26—8．36，C（NaCl）=20mmol／L时，由DDA—MMT颗粒乳化制备的Pickering乳液稳定性较佳。
Wet ball mill method was applied to prepare modified montmorillonite （DDA -MMT） by the intercalation of didodecyldimethylammonium bromide （DDAB） with Na - montmorillonite （ Na - MMT） as the basic material. Then the resultant DDA - MMT was applied to emulsify liquid paraffin to form O/W Picketing emulsions under the action of ultrasound. The resultant DDA - MMT was characterized by XRD, TEM, FT - IR,contact angle measurement,Zeta potential and laser particle size analyzer. The effects of DDA -MMT mass concentration, pH of aqueous phase and ionic strength on the stability of the Piekering emulsions were also investigated. Experimental results showed that DDAB has successfully intercalated into the interlayer of Na - MMT under the mechanical action of the ball mill, causing the size, Zeta potential and three phase contact angle change from 910. 7 nm, - 26. 8 mV and 121.7° to 603. 8 nm, 38. 3 mV and 86. 9° respectively. In comparison with Na - MMT particles, DDA - MMT particles are more easily to aggregate between the oil - water interfaces and displays better emulsification stability. With the increasing of DDA - MMT mass concentration, the particle size of the Pickering emulsions decreases, the volume fraction of the emulsion increases and the stability of the emulsion becomes better. When the pH of aqueous phase is in the range of 6.26 - 8.36, and the NaCl concentration is 20 mmol/L, the stability of the Picketing emulsion prepared by DDA - MMT is in the best condition.
出处
《日用化学工业》
CAS
CSCD
北大核心
2016年第12期697-702,708,共7页
China Surfactant Detergent & Cosmetics
基金
国家自然科学基金资助项目(21366010
21566009)
海南省重点科技计划资助项目(ZDYF2016095)
