Programme

O.15 -- Oral, VCTP-44

Date: Tuesday, 30 July 2019

Time: 17:10 - 17:30

Micro-mechanical properties of colloidal aggreates with critical Casimir forces

Minh Triet Dang (1), Truc Anh Nguyen (2), Hoang Xuan Trinh (3), Peter Schall (4)

(1) School of Education, Cantho University, Cantho, Vietnam (2) Faculty of Basic Science, Cantho University of Technology, Cantho Vietnam (3) Institute of Physics, Vietnam Academy of Science and Technology, Hanoi, Vietnam (4) Institute of Physics, University of Amsterdam, Amsterdam, the Netherlands

Microscopically, gel networks, formed by the aggregation of attractive colloidal particles, are widely used to control the rheological properties of complex materials. Network elasticity characterized via the storage and loss moduli, bending stiffness is highly sensitive to the connectivity, rearrangement of particle aggregates and shows a strong time evolution due to their complex energy landscape. This network elasticity is central in foods and in the cell cytoskeleton, where networks of biopolymers give the cell the mechanical properties. In this talk, we investigate the role of both spherical and anisotropic colloids with novel critical Casimir forces on the bonding morphology and micro-mechanical properties of these chain-like colloidal aggregates. Computer simulations using an effective critical Casimir pair potential with modern experimental confocal observations show the morphology changes and the increase of storage and loss moduli with aging time. These results highlight the impact of engineering building blocks on the way to design colloidal superstructures with tunable mechanical behavior. Acknowledgement: This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.01-2018.308.

Presenter: Dang Minh Triet