報告題目:Spherical Packing Phases of Block Copolymers
報 告 人:Prof. An-Chang Shi
報告時間:2018年11月13日(周二)上午10:00
報告地點:化學(xué)樓一號會議室
邀 請 人:朱錦濤教授
報告人簡介:
An-Chang Shi is a professor of physics at McMaster University. He received his B.Sc. in physics from Fudan University in 1982 and his Ph.D. in physics from University of Illinois at Urbana-Champaign in 1988. From 1988 to 1992 he was a Post-Doctoral Fellow and Research Associate at McMaster University. He joined Xerox Research Centre of Canada as a Member of Research Staff in 1992 and moved to McMaster University as an Associate Professor in 1999. He was promoted to Professor in 2004. Dr. Shi received a Premier’s Research Excellent Award in 2000 and was elected to Fellow of American Physical Society in 2010. In 2007, he was appointed as a Changjiang Visiting Professor at Fudan University. Dr. Shi has worked on a wide range of topics in theoretical condensed matter physics, including crystal shapes, superconductivity and soft matter theory. His current research focuses on the development of theory for inhomogeneous polymeric system, the investigation of phase diagrams of block copolymers, and the study of kinetic pathways of transitions between stable and metastable phases.
報告簡介:
Spherical packing is an interesting problem in mathematics and physics with a long history dated back to the work of Kepler and Lord Kelvin. In particular, spherical packing is intimately related to the structure of ordered phases. The observation of ordered phases in hard-condensed matter systems such as metallic alloys has a long history in materials physics. In recent years, intricate periodic and aperiodic spherical packing phases have emerged in a host of soft matter systems including supramolecular assemblies, surfactants and block copolymers, underscoring the universality of emergent order in condensed matter. The richness of the phase behavior in soft matter is exemplified by block copolymers, providing an ideal system to study the origins and stability of periodic and aperiodic order in condensed matter physics. Our recent study of block copolymer systems using the self-consistent field theory reveals that one key mechanism of forming complex spherical phases is the conformational asymmetry of the blocks. Furthermore, we have predicted that the segregation of different polymeric species in block copolymer blends provides another mechanism to stabilize spherical packing phases with very different sized-spherical domains. I will summarize recent progresses on this fascinating topic and discuss possible future research directions.