文献类型：期刊文献

中文题名：SiO_2-PDMAEMA稳定的Pickering乳液及其响应性能

英文题名：SiO_2-PDMAEMA Stabilized Pickering Emulsion and Its Responsive Properties

作者：邱玉峰[1];曹琛[1];陈晓露[1];韩霞[1];刘洪来[1]

机构：[1]华东理工大学化学与分子工程学院,上海200237

年份：2018

卷号：44

期号：5

起止页码：675

中文期刊名：华东理工大学学报（自然科学版）

外文期刊名：Journal of East China University of Science and Technology

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD_E2017_2018】；

基金：国家自然科学基金(91534103);中国石油科技创新基金(2017D-5007-0204)

语种：中文

中文关键词：PDMAEMA;二氧化硅颗粒;Pickering乳液;响应性

外文关键词：PDMAEMA;silica particle;Pickering emulsion;responsive behavior

摘要：利用具有温度和pH响应性的聚甲基丙烯酸N,N-二甲基氨基乙酯(PDMAEMA)对二氧化硅颗粒进行表面改性,获得了具有响应性的颗粒乳化剂SiO_2-PDMAEMA,这种乳化剂可以增加正己烷-水双相体系的稳定性,使之形成具有温度和pH响应性的乳液。研究表明,乳液体系具有显著的pH敏感性:在酸性条件下,乳液破乳;通过调控水相pH可实现乳液破乳-乳化的循环。虽然SiO_2-PDMAEMA颗粒在水中表现出明显的低临界溶解温度(51℃),但温度对Pickering乳液稳定性的影响并不显著,升高温度,有利于乳液的稳定。
Pickering emulsions have been used in a variety of industries including petroleum,food,biomedicine,pharmaceuticals,and cosmetics due to their significant advantages such as stability,compatibility,toxicity-free and low cost over traditional surfactant stabilized emulsions.Recently,Pickering emulsions with stimuli-responsive properties have attracted increasing attention because of excellent and unique properties in controlled stabilization and destabilization.Stimuli-responsive Pickering emulsions can be prepared by stimuli-responsive particles possessing tunable surface properties and surface wettability,which in turn alter their position at the two-phase interfaces.In this work,poly(2-(dimethylamino)ethyl methacrylate)(PDMAEMA)was used to modify the silica particles to make the responsive emulsifier(SiO 2-PDMAEMA)as well as responsive Pickering emulsions.Because of the tertiary amino groups at the end of the polymer chain and the hydrophobic alkyl backbone,PDMAEMA has pH and thermal responsive properties.Under low pH condition and/or at low temperature,the polymer becomes more hydrophilic due to the protonation of the amino groups and the hydrogen bonding between the amino groups and water molecules.Due to such thermo/pH dual-responsive property of PDMAEMA,the hydrophilic-hydrophobic surface property of SiO 2-PDMAEMA emulsifier can be easily modified.As a result,SiO 2-PDMAEMA particles can stabilize the hexane-water biphasic system and form stable Pickering emulsions at room temperature.The obtained Pickering emulsion is sensitive to pH and de-emulsification occurred at lower pH and emulsification is recovered by increasing pH.Zeta potential of SiO 2-PDMAEMA particles in aqueous dispersions show an isoelectric point(pI)about 9,indicating the deprotonation of the amino group of PDMAEMA when pH>9.Although SiO 2-PDMAEMA particles exhibit an obvious thermo-responsive behavior in aqueous suspensions with a lower critical solution temperature(LCST,51℃),the Pickering emulsion system don’t show significant thermo-responsive behavior.High temperature will benefit to the stability of the Pickering emulsion due to the increased hydrophobic aggregation of the emulsifier particles.The new emulsification system with stimuli-responsive properties will show a great perspective in many applications e.g.drug delivery,multiphase catalysts and surface science,etc.