UK Polymer Showcase 7 th / 8 th September 2004 Cedar Court Hotel

S OF LECTURES UK POLYMER SHOWCASE 7/8 SEPTEMBER 2004 CEDAR COURT, WAKEFIELD LIST OF ORAL PRESENTATIONS Professor Tom McLeish, Director Searching Through Polymer Dynamics with the IRC in Polymer Science & Technology Finest-toothed Comb.... Dr. Martin Buzza Rheology of Hyperbranched Polymers IRC, Leeds Dr. Lian Hutchings HyperMacs and DendriMacs. The next generation of IRC, Durham well-defined, highly branched polymers. Professor Ruth Duncan Polymer Therapeutics: Biological Rationale for Cardiff University Design and Clinical Experience with the First Nanomedicines Dr. Neil Cameron IRC Research at the Polymers-Bioscience Interface IRC, Durham Professor Sheila MacNeil Development of a Plasma Polymer Surface for University of Sheffield Wound Healing Directors' Introduction: Professor Tom McLeish 15 Years of the IRC and the rest...... Professor Phil Coates Polymer Centre of Industrial Collaboration Richard Simpson The Faraday Plastics and Polymer Partnership Sebastian Conran Designer Plastics: The Guile, Art and Practicality of Conran & Partners Successfully Designing with Polymers. Professor David Bott Department Stores, Chain Stores and Boutiques The Future of the UK Chemical Industry Dr. Wilhelm T. S. Huck Nanostructured Polymers in Optoelectronic Devices University of Cambridge Professor Tony Ryan How Does Flow Effect Polymer Crystallisation? Associate Director, IRC Sheffield Professor Han Meijer Modelling and Validation of Viscoelastic Stress University of Eindhoven Induced Crystallization Dr. Peter Hine Hot Compacted Polymer Composites: New Science IRC, Leeds and Technology Bill MacDonald, Flexible Electronics: Structural Materials DuPont Teijin Films Underpinning Functional Materials Professor Richard Jones Polymers at Interfaces: From Plastic Electronics to University of Sheffield Soft Nanotechnology Professor Phil Coates The Dream Machine Process and Product Associate Director, Measurements for Enhanced Process Understanding, IRC Bradford Modeling and Control Searching through polymer dynamics with the finest-toothed comb.... Tom McLeish Director, IRC in Polymer Science & Technology A B S T R A C T From plastics processing to molecular biology, polymer chain architecture plays a vital role in design for purpose at the molecular level. Addressing the science of polymer architecture similarly requires the careful synthesis of model macromolecules in which not only molecular weight, but also architecture, is carefully controlled. Here we look, from several angles, at the remarkable properties of comb-like architectures as one model case of branched polymers. Monodisperse combs of polybutadiene and their hydrogenated variants have been a vital test material in the cross-IRC collaboration in “Microscale Polymer Processing”. Recently extended by a 4-year grant from EPSRC, this large project followed several model classes of polymer melt from synthesis, through rheology to final process flows and products. Christine Fernyhough (Sheffield) manufactured sufficient comb material to process in neat form in the fully flowvisualised “Multipass Rheometer” in Malcolm Mackley’s laboratory (Cambridge), and to be measured in pure extensional flow by David Groves (Leeds). The rheological and flowfield results were compared with tube-model theories of how molecules control rheology by Nat Inkson (Leeds). Results show how using monodisperse materials in this way is akin to high-resolution microscopy: all the features are brought into sharper focus and can be treated in a more quantitative way. Pure comb melt stress-field in flow (left half) compared with predicted stresses from a molecular model (right) (Nat Inkson) The comb and the pure tree (dendrimer) together for the boundaries of the topological world in which all branched polymers exist. Industrial materials lie in the land between. The world of long-chain branching in rheological terms, showing how pure combs and pure trees create the boundaries of the possible (Daniel Read). The naturally occurring comb polyelectrolyte system aggrecan, found as the viscoelastic matrix in cartilage composites In a very different world, charged comb polymers in aqueous solution create important rheological properties in impact-resistant and lubricated areas of the body, such as load-bearing joints. Lubricating flow requires high “normal stresses” under shear – another property in which molecular combs in solution excel. Now entanglement physics is exchanged for electrostatics in solution, but the same underlying requirement is present: tailor molecular stretch to the shear rates of the fluid! Rheology of Hyperbranched Polymers Martin Buzza I.R.C. in Polymer Science & Technology, School of Physics & Astronomy, University of Leeds, Leeds LS2 9JT