Exploration of sub-diffusive motion in high-value polymers

Complex and potentially high-value polymers have been found to possess anomalous sub-diffusive motion, which has not yet been fully explained. Understanding this motion will provide fundamental breakthroughs in our ability to predict the properties of synthetic high-value polymers and drive their adoption in new products and processes, such as sensors, coatings and hydrogels.

This PhD project will leverage our previous experience of working with peptide, phophodiester and ether-based polymer chemistries, together with analytical (e.g., NMR and laser photolysis) and recent computational developments to provide new and unprecedented exploration of sub-diffusive motion in high-value polymers. Equilibrium measurements, are typically consistent with fully disordered polymers behaving as slightly expanded random coils, taking into account excluded volume, torsional angle preferences and chain stiffness. If the energy surface describing the accessible conformational space were smooth, then sampling over this energy surface would be largely diffusive, and transitions between states would follow exponential kinetics. However, we recently established that peptide-linked polymers move in a clearly sub-diffusive manner over many time scales. This sub-diffusion results from the sampling of a rugged energy surface, where the barrier heights define local traps with a wide distribution of trapping times. The range of traps results from different interactions between two or more components of the polymer chain, with deeper traps representing clusters with stronger interactions. The question of whether sub-diffusive motion is a feature of many high-value polymers has not been addressed (they are normally assumed to have diffusive motion), and yet their motional properties are absolutely central to how they behave. The overall PhD aim is to determine the extent to which sub-diffusive behaviour occurs in specific important high-value polymers and to understand whether it is a universal feature of these polymers.

Contact for further Information;

Dr. Andrew Almond
Email: [Email Address Removed]
Web: https://www.research.manchester.ac.uk/portal/andrew.almond.html

Prof. Jon Waltho
[Email Address Removed]
https://www.sheffield.ac.uk/mbb/staff/jonwaltho

Applicants are expected to hold, or about to obtain, a minimum upper second class undergraduate degree (or equivalent) in Chemistry, Biochemistry, Physical Chemistry or Biophysics. A Masters degree in a relevant subject and/or further experience in Chemistry, Biochemistry, Physical Chemistry, Biophysics or Molecular modelling is desirable.