党乐平，杨 娟，卫宏远
AuthorsHTML:党乐平，杨 娟，卫宏远
AuthorsListE:Dang Leping，Yang Juan，Wei Hongyuan
AuthorsHTMLE:Dang Leping，Yang Juan，Wei Hongyuan
Unit:天津大学化工学院，天津 300072
Unit_EngLish:School of Chemical Engineering and Technology，Tianjin University，Tianjin 300072，China
Abstract_Chinese:本文利用偏光显微镜(POM)、SAXS 小角散射和旋转流变仪研究了室温下季铵盐阳离子表面活性剂Rewoquat Cl-deedmac(二甲基二酯氯化铵)/PVA(聚乙烯醇)/Glycerin(甘油)/H2O 拟三元体系的相行为和流变性能．通过实验绘制出拟三元体系的部分相图，界定出六方相、片层状相和囊泡的相图区域．结果表明，在相图上溶致液晶囊泡相占最大的区域；流变性能研究证明了溶致液晶为非牛顿流体，具有应力屈服值和较高的黏弹性，在溶致液晶相区内，体系表现出剪切稀释的性质，属于假塑性流体，层状液晶体系在整个频率扫描范围内表现为类固体性质，囊泡具有明显的屈服应力值，其频率扫描曲线类似于层状液晶，即囊泡体系也具有很高的黏弹性．另外，NaCl的加入会诱导六方相转变为层状相．本研究为表面活性剂聚合物复配体系配方设计提供了理论依据．
Abstract_English:In this paper，we investigate the phase behavior and rheological properties of the quaternary ammonium salt cationic surfactant Rewoquat Cl-deedmac(dimethyl ammonium chloride)/PVA(polyvinyl alcohol)/Glycerin/H2O pseudo-ternary system at room temperature using a polarizing microscope，small angle X-ray scattering，and a rheometer. Based on the experimental data obtained，we constructed a phase diagram of the pseudo-ternary system. Three main liquid crystal phases were identified—hexagonal，lamellar，and vesicle. The results reveal that vesicles in the lyotropic liquid crystal region occupy the largest area of the phase diagram. The rheological analysis results indicate the lyotropic liquid crystal to be a non-Newtonian fluid with yield stress and high viscoelasticity. The phase region of the lyotropic liquid crystal shows shear thinning，which is characteristic of pseudoplastic fluids. The lamellar liquid-crystal system exhibits solid-like properties over the whole frequency scanning range. The vesicles have obvious yield stress value and their frequency scanning curve is similar to that of the lamellar liquid crystal，which means the vesicle system also has high viscoelasticity. The addition of NaCl was found to induce transformation from the hexagonal to lamellar phase. The findings presented in this work provide a theoretical basis for formulating a design for a surfactant-polymer composite system.
Keyword_Chinese:Rewoquat Cl-deedmac；PVA；溶致液晶；POM；小角度 X 射线散射；流变性
Keywords_English:Rewoquat Cl-deedmac；PVA；lyotropic liquid crystal；polarizing optical microscope；small angle X-ray scattering；rheology

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