Tuning selective gas transport in polymers by manipulation of molecular orientation


Contact Dr Johan Mattsson or Dr Peter Hine to discuss this project further informally.

Project description

Polymer films are used extensively for packaging due to their processability, lightweight and transparency. The barrier properties of such films is, as would be expected, also a crucial property, particularly when used for food packaging. In some cases it is crucial to keep gases within the barrier, in other instances keeping gases from penetrating to the contents within.

Occasionally it is also advantageous to have a specially designed barrier, which would allow selective transport of particular gases in either direction. One key aspect of the polymer film that can potentially be modified during melt processing, or a subsequent solid state processing stage, is the level of preferred molecular orientation within the film. If the rate of deformation used to manufacture the film is faster than the relaxation time of the polymer chain (often controlled by the entanglement time), then the polymer chains can be trapped in a preferred orientation.

These effects might be used to custom design polymer films for important physical properties such as preferential gas transfer. The aim of this project is to assess whether preferred molecular orientation can be used to affect gas transport, and for what particular single gas (oxygen, nitrogen, water vapour etc) or gas mixtures. Careful annealing of oriented films can produce different levels of molecular orientation at different length scales, and the interest is to see if this can be used to tailor gas transport.

The project will use small scale, but relevant, processing facilities at Leeds to manufacture films with controlled levels of orientation. The trapped orientation, and its dynamics, will be assessed by a range of experimental techniques all available at Leeds including dielectric spectroscopy, birefringence, differential scanning calorimetry and rheology, as well as the important underpinning gas diffusion measurements.

Entry requirements

Applications are invited from candidates with, or expecting, a minimum of a UK upper second class honours degree (2:1) in a relevant discipline, a Master's degree in a relevant discipline, or both.

If English is not your first language, you must provide evidence that you meet the University’s minimum English Language requirements.

Additional staff contact

Daniel Read

How to apply

Formal applications for research degree study should be made online through the university's website. Please state clearly in the research information section that the PhD you wish to be considered for is 'Tuning selective gas transport in polymers by manipulation of molecular orientation' as well as Dr Johan Mattsson and Dr Peter Hine as your proposed supervisors.

We welcome scholarship applications from all suitably-qualified candidates, but UK black and minority ethnic (BME) researchers are currently under-represented in our Postgraduate Research community, and we would therefore particularly encourage applications from UK BME candidates. All scholarships will be awarded on the basis of merit.

If you require any further information please contact the Graduate School Office, e: maps.pgr.admissions@leeds.ac.uk