f

Dr Michael Weir

Profile

Department: Physics and Astronomy

Group: Prof. Nigel Clarke (Soft Matter Research Group)

Status: Postdoctoral Research Associate

Email: m.weir@sheffield.ac.uk

Biography

I studied for an M.Sci. in Physics (2002-2006) at the University of Nottingham. I then came to Sheffield to study a Ph.D. with Professor Richard A. L. Jones FRS in the Polymer Physics group, graduating in 2010 with a thesis on voltage-induced swelling and de-swelling of weak polyelectrolyte brushes.

From 2010 to 2012 I worked as a post-doc at ANSTO just outside of Sydney, Australia. Here I learned small-angle X-ray and neutron scattering techniques, as applied to a diverse range of polymeric systems as part of the Australian CRC for Polymers (www.crcp.com.au). Upon my return to the UK I spent some time working in materials science publishing.

In 2013 I returned to Sheffield to start a post-doc with Professor Nigel Clarke in the Department of Physics and Astronomy. In this project I use small-angle-scattering of X-rays and neutrons to characterize polymer graphene-nanocomposites (see ‘Research Interests’).

Research Interests

My research interests are in polymer physics. I use scattering and reflectometry techniques to study the conformations of polymer chains under confinement, e.g. tethered to surfaces, in or near crystallites, or under the influence of nearby nanoparticles.

My current project studies graphene-polymer nanocomposites as part of the EPSRC project ‘GRAPOL’ (dur.ac.uk/grapol). Due to their superior properties and high interfacial area, graphene materials present an exciting step forward as filler materials for nanocomposites. Graphene materials offer reinforcement at very low levels of loading, typically 1% by volume or less, making them economical for improving properties such as permeability, thermal and electrical conductivity, and for lightweighting.

In this project I use mechanical and rheological testing to explore the strength of our composites, as well as using small-angle X-ray and neutron scattering techniques to study the shape, size and dispersion of the graphene materials. I use neutron scattering techniques to study the structure and dynamics of the polymer chains and monomers, seeking to understand the physical interactions between polymer and nanofiller. Our aim is to build an understanding of our nanocomposites that begins at a molecular level and extends up to the industrial scale.

Recent Publications

1. Yiapanis, G. et al. Molecular mechanism of stabilization of thin films for improved water evaporation protection. Langmuir 29, 14451–9 (2013)

2. Topham, P. D. et al. The relationship between charge density and polyelectrolyte brush profile using simultaneous neutron reflectivity and in situ attenuated total internal reflection FTIR. Langmuir 29, 6068–76 (2013)

3. Hsu, Y.-C. et al. A fundamental study on photo-oxidative degradation of linear low density polyethylene films at embrittlement. Polymer 53, 2385–2393 (2012)