A Novel Manufacturing Process for the Extrusion of Helical Auxetic Yarns

An auxetic material is one which exhibits a negative Poisson's ratio: this is a counter-intuitive physical property whereby the material becomes thicker when stretched.

An exciting new invention in the field of auxetics is the helical auxetic yarn. This is a yarn composed of two conventional fibres, one helically wrapped around the other. By appropriate choice of materials and geometry this yarn can be made such that it effectively gets wider when stretched. This opens a panorama of interesting possibilities for high-performance or 'smart' textiles. Uses include pore-opening fabrics in healthcare or security and defence sectors, filtration, colour-change fabrics for healthcare, safety harnesses or fashion, and disaster mitigation - tornado, hurricane or earthquake protection.

It is easy to make small quantities of auxetic yarn for laboratory trials. These trials have provided, and continue to provide, exciting evidence of benefits to society. To exploit these opportunities we need to develop a method of manufacturing the yarn in industrial scale quantities and at a quality with which commercial enterprises can work and earn profit.

This research project is developing new extrusion manufacturing techniques to produce helical auxetic yarns and, in particular, developing a new version of the yarn which will truly unleash the commercial potential of the technology.

We propose here a research project into novel manufacturing methods for the production of novel textiles with wide-ranging applications including healthcare, security, safety and filtration. We are already exploring these with our proposed partners and extended network. The outputs of the project are fundamental to the commercial and economic development of a new field and range of technical textiles which offer a global leadership opportunity to UK industry. By ensuring a complete supply chain in the project partnership we are ideally placed to disseminate and exploit in all major directions, from new extrusion technology and equipment, through new forms of fibre (auxetic and nonauxetic) - polymeric or otherwise - to new forms of textile (technical, smart materials, fashion).

Our Impact Plan embraces a thorough approach to dissemination, communication and interaction with both the wider academic community and the public. We shall run at least one national workshop event with a half-day session focused on the academic community and potential developments for research outcomes of the project, and a half-day session aimed at the technical textiles industry aiming to apprise them of the commercial opportunities presented by successful outcomes of the finished coextrusion/pultrusion processes. Our already strong relationships with the likes of NIHR and Materials KTN will be extended and used to engage wider participation and awareness through seminars and workshops such as the NIHR's Regional Research conferences and the KTN events such as the recent Materials for a Safer World. Through our established partnership with the Centre for the Protection of National Infrastructure we are able to communicate progress and opportunities in blast mitigation, personal protection and security. Working with the University's press office, the Investigators have an excellent track record in PR activities, with recent press releases on auxetic textiles gaining national (BBC Radio 4) and local radio airtime involving interviews with our research staff, BBC website exposure and widespread national newspaper coverage, including The Daily Mail and The Sun.

The majority of dissemination and communication activity to date has been at minimal cost and we expect this work to continue to be highly cost-effective. There remains however, the imperative to engage on a global basis and this will incur some levels of cost, in the form of presentations at international academic conferences including Polmyer Fibres, International Conference on Composite Materials, Advances in Materials and Processing Technologies. Attendance at Techtextil - the biennial global premier technical textiles event (next taking place in Frankfurt in 2011) is a prerequisite for commercial engagement and we shall send a delegation to this event and submit presentations to the symposium element of this event. Appropriate travel and subsistence costings are detailed in the Justification for Resources. We expect to produce at least 6 journal papers of international standing.