Materials/MRL Joint Colloquium: Peter F. Green

DOW LECTURER
MATERIALS DEPARTMENT/MRL JOINT COLLOQUIUM

Professor Peter F. Green
Chair, Department of Materials Science and Engineering
Director, Center for Solar and Thermal Energy Conversion in Complex Materials:
A DOE Energy Frontier Research Center, University of Michigan

Phase Behavior and Properties of Thin Film Brush-Coated Nanoparticles/Homopolymer Mixtures

February 26, 2010 | 4:00pm | MRL 2053

Abstract
The incorporation of nanoparticles of varying chemistries into polymer hosts has a profound effect on the properties of the polymers, even with very small nanoparticle concentrations. Depending on the functionality of the polymer and of the nanoparticles a diverse range of properties, from mechanical and thermal to optical and electronic, may change significantly. A primary challenge in polymer nanocomposites (PNCs) is that they possess non-equilibrium morphologies (particle aggregation, particle bridging interactions and phase separation at various length scales) due to the complex interplay between enthalpic and entropic interactions. The properties of PNCs cannot be predicted based on knowledge of the composition alone, and vary significantly, in very unusual ways, with the structural organization of the constituents. One effective strategy to control the morphology of PNCs is to graft polymer chains of varying chemistries, grafting densities, s and degrees of polymerization, N, onto nanoparticles of diameters, D. We show how D, N, P, and senable control of the phase behavior and the properties (optical and dynamics). Specifically, we examined the phase behavior and properties of thin film mixtures of polystyrene (PS)-grafted gold nanoparticles with different polymer hosts: PS, polymethyl methacrylate (PMMA); tetramethyl bisphenol polycarbonate (TMPC) and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV).

Hosted by Graduate Students for Diversity in Science

LIGHT REFRESHMENTS WILL BE SERVED PRIOR TO THE SEMINAR AT 3:45PM