EPSRC logo

Details of Grant 

EPSRC Reference: GR/S73037/01
Title: The Structure of Flow-Aligned Synthetic and Bio-Polymers in Solution Probed by Small Angle X-ray and Light Scattering
Principal Investigator: Hamley, Professor IW
Other Investigators:
Researcher Co-Investigators:
Project Partners:
Department: Sch of Chemistry
Organisation: University of Leeds
Scheme: Standard Research (Pre-FEC)
Starts: 04 May 2004 Ends: 31 August 2005 Value (£): 178,869
EPSRC Research Topic Classifications:
Bioprocess Engineering Materials Characterisation
Rheology
EPSRC Industrial Sector Classifications:
Pharmaceuticals and Biotechnology
Related Grants:
Panel History:  
Summary on Grant Application Form
Polymer solutions are often processed by flow through tubes, nozzles and filters, and it is thus of considerable technological relevance to consider the behaviour of polymer chains under flow. It is also of great fundamental interest to understand the extension of polymer chains under flow, and the orientation of self-organizing anisotropic polymer structures (peptide fibrils, DNA fragements, wormlike micelles) when subject to an aligning flow field. Many samples of novel polymers, in particular biopolymers, are available in small quantities, which make the use of conventional methods to align samples for structure determination difficult or impossible. The present proposal is to develop a flow cell for small sample volumes based around a capillary geometry. This will also enable shear rates up to -one million 1/s to be accessed, enabling the exciting possibility of investigating new phenomena under extreme flow conditions. The change in orientation of the self-organizing polymers will be examined by small-angle x-ray scattering at the SRS, Daresbury lab and by small-angle light scattering in our lab at Leeds. In both cases, area detectors will be used to obtain scattering patterns from the oriented samples. Furthermore, in both cases, time-resolved measurements are possible, permitting the investigation of kinetic processes at an unprecedented level of detail. The combination of both techniques is particularly powerful because it will be possible to probe changes in orientation of polymer chains and self-organized structures through SAXS, and changes in texture (eg. in a two-phase region) through small-angle light scattering. We propose to investigate flow-induced alignment in a tightly focussed range of problems of major interest in biophysics and physical chemistry of soft condensed matter. In particular, we will investigate (i) The orientation of peptide fibrils in the vicinity of the isotropic - nematic fluid phase transition boundary, (ii) The overstretching transition in DNA fragments under extreme flow conditions to determine whether a helix - coil transition occurs, (iii) Phase separation into possible nematic and isotropic phases in solutions of wormlike surfactant micelles, (iv) Shear-induced disordering of rod-like block copolymer micelles and (v) Concentration fluctuations in a homopolymer solution close to the binodal, wehere a coupling of concentration fluctuations to the flow field is anticipated. The device, although conceptually simple, is expected to lead to significant breakthroughs in these exciting topics in complex fluid research. The facility will also be made available to other users. The work addresses important issues in contemporary complex fluid research, and will have broad impact.
Key Findings
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Potential use in non-academic contexts
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Impacts
Description This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Summary
Date Materialised
Sectors submitted by the Researcher
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Project URL:  
Further Information:  
Organisation Website: http://www.leeds.ac.uk