MSE Ph.D. Defense – Weinan Xu

Date: Wednesday, October 21, 2015
Time: 9:00 am
Location: Room 3201A, Molecular Science and Engineering building.

Committee:

Prof. Vladimir Tsukruk (Advisor), MSE

Prof. Paul Russo, MSE

Prof. Zhiqun Lin, MSE

Prof. Valeria Milam, MSE

Prof. Alexander Alexeev, ME

Title: Responsive Micro- and Nano-Structures Through Interfacial Assembly of Star Polymers

Abstract:

Star polymers with stimuli-responsive arms constitute a unique class of responsive materials, their responsive properties are quite distinct from their linear counterparts due to the spatial confinement and complex intramolecular interactions of the arms.  In order to study the responsive properties of star polymers at the molecular level, and utilize them to fabricate functional microstructures, it is critical to confine them at interfaces and assemble them via various intermolecular non-covalent interactions.  This work will focus on the solution phase behavior of responsive star polymers (to pH, ionic strength, temperature), their 2D interfacial assembly by using Langmuir-Blodgett technique; as well as the 3D layer-by-layer assembly via electrostatic interaction or hydrogen bonding.  The assembled microstructures include thin films, polymersomes and microcapsules with the ability to reversibly change their structures and permeability, which can lead to applications in smart coating, drug delivery, self-healing materials and microreactors.