Rheology of colloidal particles in lyotropic hexagonal liquid crystals: the role of particle loading, shape, and phase transition kinetics

被引：0
作者：
Siddharth Kulkarni
Prachi Thareja
机构：
[1] Indian Institute of Technology,Department of Chemical Engineering
来源：
Rheologica Acta | 2016年 / 55卷
关键词：
Hexagonal phase; Liquid crystals; Rheology; Colloidal particles;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
The rheology of self-assembled elongated iron oxyhydroxide (FeOOH) and spherical silica (SiO2) particles in hexagonal (H1) liquid crystal (LC) phase of water and non-ionic surfactant C12E9 is investigated by varying particle concentration and cooling rate. The rheology data shows that both SiO2/H1 and FeOOH/ H1 LC composites exhibit a higher G′ when compared to the particle-free H1 phase, with increasing particle loading and cooling rate. FeOOH particles improve G′ of the H1 phase more significantly than SiO2 particles due to the formation of an interconnected network at H1 domain boundaries at cooling rates of 1 and 2 ∘C/min. We hypothesize that self-assembly of particles at domain boundaries leads to a decreased mobility of defects causing an increase in elasticity of particle-laden H1 phase. Dynamic strain sweep and creep experiments show a non-linear stress–strain relationship attributed to the alignment of micellar cylindrical rods under shear.
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页码：23 / 36
页数：13
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