Topic: Interaction and dynamics of soft matter near the surface

Speaker: Wei Tao (To NGAI)

Report time: 10:00 AM, July 9, 2019

Location: Room 2217, Mechanical Hall

Introduction:

To NGAI now is Professor in the Department of chemistry, Assistant Dean (Research) of the Faculty at the Chinese University of Hong Kong (CUHK), and Fellow of the Royal Society of Chemistry (FRSC). He received his B.Sc. in chemistry at CUHK in 1999. In 2003, he obtained the Ph D at the same university, where he worked on light scattering and polymer interaction in solution. He moved to BASF (Ludwigshafen, Germany) in 2003 as the postdoctoral fellow for two years, working on colloids and surface chemistry. After a short postdoctoral training the Chemistry Department at the University of Minnesota in 2005, he joined the Chemistry Department at CUHK in 2006 as a research assistant professor He has been appointed as an assistant professor in 2008, and early promoted to associate professor in 2012. In 2017, he was promoted to Professor. His current research interests center around the colloids, surface chemistry, polymers and soft matter.

Introduction to the report:

Understanding the complex dynamics and interactions near a surface is important for the comprehensive characterization of soft matter. Ubiquitous phenomena, such as the adsorption of polymers chains at the interface or the sticking of a colloid to a rigid substrate, are highly related with near-surface dynamics, involving time-dependent surface interactions and structures. In this talk, I will discuss recent advances in the using of the non-intrusive optical technique of Total Internal Reflection Microscopy (TIRM)for measuring particle-surface interactions after the particle and surface are physically adsorbed or grafted with neutral or charge polymers. I will also describe the approach that includes coupling magnetic tweezers (MD) to TIRM for the detachment of a colloid to a solid surface and studying soft microgels and polymers near the surface as a function of frequency, time and separation distance.

Host: School of Mechanical Engineering, Key Laboratory of Advanced Materials Technology

Contact: Professor Cui Shuxun