tailieunhanh - Gelation of anisotropic colloids with short range attraction

Colloidal gels are space-spanning networks that form solids at dilute particle volume fractions. The kinetic process of gelation is central to understand the flow of complex fluids. Here, we report a simulation study of colloidal gelation of anisotropic colloids with attractive Lennard Jones potential. | VNU Journal of Science Mathematics Physics Vol. 36 No. 1 2020 30-37 Original Article Gelation of Anisotropic Colloids with Short-Range Attraction Dang Minh Triet1 Truong Quoc Tuan2 Tran Van Thien2 1 School of Education Can Tho University Vietnam 2 College of Natural Sciences Can Tho University Vietnam Received 10 January 2020 Revised 19 February 2020 Accepted 21 February 2020 Abstract Colloidal gels are space-spanning networks that form solids at dilute particle volume fractions. The kinetic process of gelation is central to understand the flow of complex fluids. Here we report a simulation study of colloidal gelation of anisotropic colloids with attractive Lennard- Jones potential. These forces quasi-model the critical Casimir effect far from the critical solvent fluctuations acting on colloidal patches. By tuning the depths of the patch-to-patch particle interactions and the selected colloidal patches we dynamically arrest the colloids to form gels. We find that thermal density fluctuation is the key factor to activate colloidal cluster space spanning the balance between clustering and break-up mechanism is important for the gelation process of anisotropic systems. These results open new opportunities for studying the structural modifications of colloidal gels formed by anisotropic particles and shed light on non-equilibrium behavior of anisotropic colloidal building blocks. Keywords Gelation anisotropic colloids short-range attraction. 1. Introduction Microscopically colloidal gels are dilute space-spanning networks that form solids at dilute particle volume fraction 1 which allows to control the rheological properties of complex materials. In colloidal science one can form these networks by aggregating attractive colloidal particles 2-4 measures the mechanics of these networks via the storage and loss moduli and shows a strong time evolution of colloidal gel formation due to the complex energy landscape 5 . This network elasticity is essential in food industry