In-mould Gel Coating for Resin Transfer Moulding

Fibre-reinforced polymer matrix composites find use in most transport applications, chemical plant, renewable energy systems, pipelines and a variety of other industries. Many of these applications require a separate surface finish for cosmetic and/or durability reasons. This coating, known as the gel-coat, is normally applied onto the mould tool before the structural laminate is moulded against the coating. The majority of the volatile organic components (VOC) in the coating will react during the polymer curing process, but the application process is such that some VOC will be emitted into the workplace and the environment. A consortium funded by the Technology Strategy Board call Meeting the Challenge of the Zero Emission Enterprise is developing a proprietary system for In-Mould Gel Coating in the context of Resin Transfer Moulding and related processes. Gel-coated laminates have been manufactured using several process variations. The surface finish has been measured using both fractal dimension determined from digital images and Wavescan DOI. Z-direction tensile strength tests have been undertaken to establish the interfacial bond strengths. The new in-mould gel-coating process has potential to improve workplace safety and reduce environmental impact during the manufacture of composite components.