羧酸盐型表面活性剂对功能化Gemini表面活性剂流变性质的影响

Effect of Carboxylate surfactants on the Rheological Properties of A Functional Gemini Surfactant

摘要:

利用稳态和动态剪切实验考察了功能化Gemini表面活性剂1,3双-（二羟乙基十二烷基溴化铵）-丙烷（简写为12(2OH)-3-12(2OH)2Br）与传统阴离子表面活性剂（十二酸钠、十四酸钠和十六酸钠）混合体系在25 ℃下的流变性质。12(2OH)-3-12(2OH)2Br的浓度为50 mmol/L时，十二酸钠、十四酸钠和十六酸钠均可以增强溶液的黏弹性。十二酸钠与12(2OH)-3-12(2OH)2Br的混合摩尔比β为0.3时，溶液的零剪切黏度η0出现最大值，为12.35 Pas，平台模量G΄∞为31.88 Pa；β=0.4时，G΄∞值为14.67 Pa.。混合体系的黏弹性顺序为：十二酸钠/12(2OH)-3-12(2OH)2Br >十四酸钠/12(2OH)-3-12(2OH)2Br >十六酸钠/12(2OH)-3-12(2OH)2Br。改变12(2OH)-3-12(2OH)2Br的浓度到60 mmol/L且十二酸钠/12(2OH)-3-12(2OH)2Br的混合摩尔比β为0.3时，零剪切黏度η0和平台模量G΄∞均增大，分别为33.92 Pas 和46.41 Pa。

Abstract:

The rheological properties of functional Gemini surfactant propanediyl-1,3-bis(dihydroxylethyldodecylammonium bromide) (12(2OH)-3-12(2OH)2Br) in the presence of small amount of traditional carboxylate surfactant, Sodium Laurate (SL), Sodium Myristate (SM) and Sodium Palmitate (SP), respectively, were investigated by steady state and dynamic rheological measurements at 25 oC. It was found that the addition of small amount of anionic surfactants has an obvious effect on the viscoelasticity of 12(2OH)-3-12(2OH)2Br solutions. The molar ratio (β) of anionic surfactant to cationic surfactant in mixed solution was 0.3, the zero shear viscosity got a maximum, 12.35 Pas and the G΄∞ was 31.88 Pa. When β=0.4, G΄∞ was 14.67 Pa. The sequence of solution viscoelasticity was SL/12(2OH)-3-12(2OH)2Br >SM/12(2OH)-3-12(2OH)2Br >SP/12(2OH)-3-12(2OH)2Br. When the concentration of 12(2OH)-3-12(2OH)2Br was 60 mmol/L, the zero shear viscosity was 33.92 Pas and G΄∞ was 46.41 Pa in the mixtures of SL/12(2OH)-3-12(2OH)2Br where β was 0.3, respectively.