双金属氢氧化物与改性海藻酸钠协同稳定液体石蜡/水乳液  

Liquid paraffin/water emulsion stabilized by synergistic action of bi- metal hydroxide and modified sodium alginate

作　　者：刘若林[1] 李嘉诚[1] 颜慧琼[1] 李晓璇[1] 程春风[1] 林强[2] 

机构地区：[1]海南大学材料与化工学院,海南海口570228 [2]海南师范大学化学化工学院,海南海口571158

出　　处：《日用化学工业》2014年第7期361-365,共5页China Surfactant Detergent & Cosmetics

基　　金：国家自然科学基金资助项目(21366010);"十二五"国家科技支撑计划资助项目(2011BAE06A06-7)

摘　　要：采用非稳态共沉淀法合成了Mg/Al双金属氢氧化物(LDH)。通过偶联酯化反应将疏水性的胆固醇(Chol)基接枝到海藻酸钠(Alg)上,制备了两亲性的改性海藻酸钠(Alg-Chol)。以Alg-Chol和LDH作为复合乳化剂,两者协同作用稳定液体石蜡/水乳液。采用傅里叶红外光谱(FTIR)、核磁共振氢谱(1HNMR)、透射电镜(TEM)、激光粒度仪(DLS)、接触角测量仪和光学显微镜等,分别对LDH,Alg-Chol和LDH/Alg-Chol水分散体系以及液体石蜡/水乳液的性能进行了表征。TEM和DLS结果显示LDH的平均粒径为159 nm,分散系数(PDI)为0.267。FTIR和1HNMR结果表明疏水性Chol基成功地接枝到Alg的侧链上。不同NaCl浓度下,LDH/Alg-Chol水分散体系在石蜡板上的接触角接近90°,说明LDH/Alg-Chol的润湿性较好,有利于增加乳液的稳定性。随着NaCl浓度的提高,乳液的粒径先由101.7μm增大到121.8μm,后来逐渐减小到58.1μm。这是由于LDH/Alg-Chol在乳液液滴的表面自组装成为一层界面膜,并且LDH/Alg-Chol在油/水界面吸附量的变化影响乳液的粒径大小。Mg/Al bi -metal hydroxide （LDH） was prepared via unsteady co -precipitation method. Hydrophobic cholesterol （Chol） was grafted onto sodium alginate （Alg） via coupling esterification to form an amphiphilie modified sodium alginate （Alg - Chol ）. Then the Alg - Chol and LDH was blended to be an emulsifier for synergistic stabilization of liquid paraffin/water emulsion. The LDH, Alg - Chol, LDH/Alg - Chol water dispersion, as well as liquid paraffin/water emulsion were characterized by FFIR, 1HNMR, TEM, DLS, contact angle measurement and optical microscope et al. Results from TEM and DLS showed that the average size of LDH is 159 nm, and the dispersion coefficient is 0.267. Results from FTIR and 1HNMR showed that the hydrophobic Chol group has been successfully grafted onto the side chain of Alg. With different NaCl concentration ,the contact angle of LDH,/Alg -Chol water dispersion system on paraffin plate is near to 90~, which denotes that the wetting power of LDH/Alg - Chol is quite high and is beneficial to upgrade the stability of the emulsion. As the concentration of NaCl increases, the particle size increases from 101. 7 μm to 121.8 μm,then gradually drops to 58.1 μm. This is due to the LDH/Alg - Chol self - assembles to form an interface film on the surface of the liquid particles of the emulsion and the particle size of the emulsion is affected by the change of amount of LDH/Alg - Chol adsorbed on the oil/water interface.

关 键 词：改性海藻酸钠 胆固醇 Mg Al双金属氢氧化物 Pickering乳液 

分 类 号：O648.23[理学—物理化学]