摘要
系统研究了阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)对生物质颗粒珍珠粉制备Pickering乳液的类型、微观结构的影响,同时解析了CTAB/珍珠粉稳定乳液从O/W型到W/O型再到O/W型的双重相转变现象。通过分散性观察、Zeta电位的测定、三相接触角和珍珠粉的荧光标记等手段深入剖析了CTAB与珍珠粉颗粒之间的相互影响。结果表明,在未添加CTAB和CTAB浓度较低时(0.01 mmol/L)时,珍珠粉能单独形成O/W型的Pickering乳液,乳化粒子为非球形且有一定聚结。当CTAB的浓度增加到0.05和0.20 mmol/L时,CTAB在珍珠粉表面吸附增强了颗粒的疏水性,润湿性的变化导致乳液类型从O/W型转变到W/O型,此时乳液的微观结构为球形,且尺寸分布较窄。随着CTAB浓度的进一步增加到0.90 mmol/L,CTAB在油水界面上取代吸附的珍珠粉颗粒,荧光显微镜观察验证了此时形成的O/W型乳液是由过量的CTAB来稳定。即通过简单地增加阳离子表面活性剂CTAB的浓度,就能实现乳液从O/W型到W/O型,再到O/W型的双重相转变。
The effect of cationic surfactant cetyltrimethyl ammonium bromide(CTAB) on the type and microstructure of Pickering emulsions prepared with biomass-based pearl powder were systematically studied. The double phase inversion from O/W type to W/O type and then to O/W type of emulsions stabilized by CTAB/pearl powder was analyzed. The interaction between CTAB and pearl powder particles was analyzed by dispersion observation, Zeta potential determination, the three-phase contact angles characterization and fluorescent labeling of pearl powder. The results show that pearl powder can stabilize O/W Pickering emulsions when CTAB is not added or the concentration of CTAB is low(0.01 mmol/L), and the emulsion droplets are not spherical and have coalescence. When the concentration of CTAB increases to 0.05 mmol/L and 0.20 mmol/L, the adsorption of CTAB on the surface of pearl powder enhances the hydrophobicity of the particles, and the change of wettability leads to the phase inversion of the emulsion from O/W type to W/O type. At the same time, the microstructure of the emulsions is spherical and the size distribution is narrow. As the concentration of CTAB increases to 0.90 mmol/L, CTAB replaces the pearl powder particles at the oil-water interface. Fluorescence microscope observation verifies that the O/W emulsion formed is stabilized by excessive CTAB. That is, by simply increasing the concentration of CTAB, the emulsion can realize the double phase inversion from O/W type to W/O type, and then to O/W type.
作者
张倩洁
沈兴亮
盛涛涛
张婉萍
许建营
Qianjie Zhang;Xingliang Shen;Taotao Sheng;Wanping Zhang;Jianying Xu(School of Perfume and Aroma Technology,Shanghai Institute of Technology,Shanghai 201418,China;Collaborative Innovation Center of Fragrance Flavour and Cosmetics,Shanghai 201418,China)
出处
《日用化学工业》
CAS
北大核心
2022年第5期468-475,共8页
China Surfactant Detergent & Cosmetics
基金
上海市科委地方能力建设项目(19090503600)。
