The physics of polymer glasses in confined geometries and in the bulk

The formation and behaviour of glassy disordered solids is one of the deepest unsolved questions in physics, as demonstrated by the seminal contributions to the problem by the 2021 Nobel laureate in physics, Giorgio Parisi.

<h2 style="margin-bottom:16px">The physics of polymer glasses in confined geometries and in the bulk</h2> <h2>Supervisors: Johan Mattsson and Simon Connell (School of Physics &amp; Astronomy)</h2> <p>The formation and behaviour of glassy disordered non-equilibrium solids is one of the deepest unsolved questions in physics, as demonstrated by the seminal contributions to the problem by the 2021 Nobel laureate in physics, Giorgio Parisi. The fact that neither the microscopic mechanisms involved in glass formation, nor the behaviour of the glassy state, are well understood makes this a key problem both within the fundamental and applied sciences.</p> <p>For long-chain molecules &ndash; polymers &ndash; our present understanding of glass-formation is particularly poor due to the complexity provided both by chain connectivity and chain flexibility; this means that the molecular motions linked to glass-formation involves an intricate interplay between intra- and inter-molecular molecular cooperativity [1]. In turn, this leads to fascinating observations including polymer-specific memory behaviour observed in the slow evolution (aging) of the out-of-equilibrium glassy state, and polymer-specific transport of ions important for the construction of safe and flexible polymer-based battery materials. Generally, polymer glasses are common for instance in construction materials, in medical implants, in optical components and in membranes for controlled transport of ions or gases. Thus, understanding polymer glass-formation directly impacts our ability to design better or totally new polymer-based applications.</p> <p>Polymers in restricted geometries, such as in thin polymer films, often show dramatic changes in behaviour, which are not well understood. This include a remarkable reduction in the glass transition temperature of ~70 K for thin free standing polystyrene films [2]. The high surface-to-volume ratio of thin films means that interfacial interactions play a strong role and the change in molecular motions at the interfaces are transferred to the film interior; we do not presently understand how this transfer takes place. Thin film polymers are highly important for coatings, in microelectronics, and in a wide array of nanotechnology applications. For the development of better, and more sustainable, technologies of the future, it is thus essential to understand how geometric confinement changes the behaviour of polymers.&nbsp;</p> <p>To address these questions, detailed experimental studies of model polymers both in thin film geometries and in the bulk are needed. Advanced experimental techniques including broadband dielectric spectroscopy, ellipsometry, calorimetry, (light, neutron and x-ray) scattering, rheology, and atomic force microscopy will be used to investigate both thin polymer films and the corresponding bulk polymers. We have recently [1] proposed a new framework for understanding polymer glass-formation, whereby the `local&rsquo; molecular motions are coupled to longer-range structural relaxations through so-called `Dynamic Facilitation&rsquo;. These ideas, and their implications for the behaviour of both bulk polymers and thin polymer films will be investigated. In addition, we are interested in determining how the generated fundamental knowledge can be utilised in relevant important appllications.</p> <p>You will work in an international dynamic research environment characterized by close collaborations between experimentalists and theorists and an inspiring mix of fundamental and applied research.</p> <p>[1] Baker, D., Reynolds, M., Masurel, R., Olmsted, P.D., Mattsson, J., Phys. Rev. X <em><strong>12</strong></em>, 021047 (2022). [2] Mattsson, J., Forrest, J.A., B&ouml;rjesson, L., Phys. Rev. E <em><strong>62</strong></em>, 5187 (2000).</p> <p>&nbsp;</p>

<p>Formal applications for research degree study should be made online through the&nbsp;<a href="https://www.leeds.ac.uk/research-applying/doc/applying-research-degrees">University&#39;s website</a>. Please state clearly in the Planned Course of Study section that you are applying for <em><strong>PHD Physics &amp; Astronony FT</strong></em> and in the research information section&nbsp;that the research degree you wish to be considered for is <em><strong>The physics of polymer glasses in confined geometries and in the bulk</strong></em> as well as&nbsp;<a href="https://eps.leeds.ac.uk/physics/staff/4117/dr-johan-mattsson">Dr Johan Mattsson</a> as your proposed supervisor.</p> <p>If English is not your first language, you must provide evidence that you meet the University&#39;s minimum English language requirements (below).</p> <p><em>As an international research-intensive university, we welcome students from all walks of life and from across the world. We foster an inclusive environment where all can flourish and prosper, and we are proud of our strong commitment to student education. Across all Faculties we are dedicated to diversifying our community and we welcome the unique contributions that individuals can bring, and particularly encourage applications from, but not limited to Black, Asian, people who belong to a minority ethnic community, people who identify as LGBT+ and people with disabilities. Applicants will always be selected based on merit and ability.</em></p> <p class="MsoNoSpacing">Applications will be considered on an ongoing basis. &nbsp;Potential applicants are strongly encouraged to contact the supervisors for an informal discussion before making a formal application. &nbsp;We also advise that you apply at the earliest opportunity as the application and selection process may close early, should we receive a sufficient number of applications or that a suitable candidate is appointed.</p> <p>Please note that you must provide the following documents at the point you submit your application:</p> <ul> <li>Full Transcripts of all degree study or if in final year of study, full transcripts to date</li> <li>Personal Statement outlining your interest in the project</li> <li>CV</li> <li>Funding information</li> </ul>

Applicants to research degree programmes should normally have at least a first class or an upper second class British Bachelors Honours degree (or equivalent) in an appropriate discipline. The criteria for entry for some research degrees may be higher, for example, several faculties, also require a Masters degree. Applicants are advised to check with the relevant School prior to making an application. Applicants who are uncertain about the requirements for a particular research degree are advised to contact the School or Graduate School prior to making an application.

The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid. Some schools and faculties have a higher requirement.

<p><strong>Priority Project</strong></p> <p class="MsoNoSpacing">A highly competitive EPSRC Doctoral Training Partnership Studentship consisting of the award of fees with a maintenance grant (currently &pound;17,668 for session 2022/23) for 3.5 years.</p> <p>This opportunity is open to all applicants, with a number of awards for Non-UK nationals limited by UKRI.&nbsp; All candidates will be placed into the EPSRC Doctoral Training Partnership Studentship Competition and selection is based on academic merit.</p> <p><strong>Self-Funded or externally sponsored students are welcome to apply.</strong></p> <p><strong>UK</strong>&nbsp;&ndash;&nbsp;The&nbsp;<a href="https://phd.leeds.ac.uk/funding/209-leeds-doctoral-scholarships-2022">Leeds Doctoral Scholarships</a> and <a href="https://phd.leeds.ac.uk/funding/234-leeds-opportunity-research-scholarship-2022">Leeds Opportunity Research Scholarship</a> are available to UK applicants. The&nbsp;<a href="https://phd.leeds.ac.uk/funding/102-bell-burnell-scholarship-award-awarded-by-the-iop">Bell Burnell Scholarship Award</a>&nbsp;is available to support applicants who are from groups that are currently under-represented in physics (awarded by the IOP).&nbsp; <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p><strong>Non-UK</strong> &ndash; The&nbsp;<a href="https://phd.leeds.ac.uk/funding/102-bell-burnell-scholarship-award-awarded-by-the-iop">Bell Burnell Scholarship Award</a>&nbsp;is available to support applicants who are from groups that are currently under-represented in physics (awarded by the IOP).&nbsp; &nbsp;The&nbsp;<a href="https://phd.leeds.ac.uk/funding/48-china-scholarship-council-university-of-leeds-scholarships-2021">China Scholarship Council - University of Leeds Scholarship</a>&nbsp;is available to nationals of China. The&nbsp;<a href="https://phd.leeds.ac.uk/funding/73-leeds-marshall-scholarship">Leeds Marshall Scholarship</a>&nbsp;is available to support US citizens. <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p><strong>Important:</strong>&nbsp; Any costs associated with your arrival at the University of Leeds to start your PhD including flights, immigration health surcharge/medical insurance and Visa costs are <strong>not</strong> covered under this studentship.</p> <p>Please refer to the <a href="https://www.ukcisa.org.uk/">UKCISA</a> website for information regarding Fee Status for Non-UK Nationals.</p>

<p>For further information about this project, please contact Dr Johan Mattsson: e:&nbsp;&nbsp;<a href="mailto:K.J.L.Mattsson@leeds.ac.uk">K.J.L.Mattsson@leeds.ac.uk</a></p> <p>For further information about your application, please contact Doctoral College Admissions: e:&nbsp;<a href="mailto:maps.pgr.admissions@leeds.ac.uk">maps.pgr.admissions@leeds.ac.uk</a></p>