Ambient storage prepreg for composites with reduced cost and environmental impact (Ambipreg)

The objective of this project is to develop a composite prepreg that has an exceptionally long shelf-life at room temperature while retaining the ability to cure at low temperature. This will leverage major competitive and environmental advantages over incumbent materials which require frozen storage, expensive transport and careful production management.

Prepreg materials typically consist of fibres (either textile or unidirectional) pre-impregnated with a resin. The resin system contains a hardener that, upon heating, crosslinks and forms a solid cured composite. However, most prepregs cure slowly at ambient temperature - typical 'outlife' 3-30 days depending on the specific formulation - so must be stored in freezers. This creates significant costs, production challenges and inefficiencies for manufacturers. Materials stored or used improperly inevitably become scrap or, worse, non-conforming/unsafe products.

The ambitious aim of this project is to break the link between outlife and cure temperature, specifically to produce tacky, reactive prepregs that cure at low temperatures without necessitating frozen storage. This will be achieved through key innovations in formulation chemistry and prepreg processing to produce novel materials with completely different behaviour.

The novel prepregs would represent a significant breakthrough in composite manufacturing, and provide major cost savings and productivity improvements for moulding companies. This technology will also reduce the amount of waste prepreg going to landfill and eliminate the need for frozen storage, which have significant economic and environmental consequences. In addition, the materials will be able to be shipped further afield, opening up opportunities for UK exports, creating new revenue and jobs.