Fiber composites based on fluoropolymer matrices
Carbon-fluoroplastic composites of fibrous structure based on carbon fabric and fluoropolymer matrices have been developed. Such composites can be used as gas diffusion layers for hydrogen fuel cells. The properties of carbon-fluoroplastic composites are compared with the characteristics of analogues, including carbon-carbon composites. It is shown that the method of obtaining fibrous composites with fluoropolymer matrices is more technologically advanced, due to fewer stages and the absence of high-temperature heat treatment stages. According to the set of characteristics required for gas diffusion layers, the developed carbon-fluoroplastic composites are not inferior to commercially available analogues. The morphology of composites was studied by scanning electron microscopy. It is shown that the chosen method of application and the conditions of heat treatment of fluoropolymers make it possible to obtain a homogeneous matrix distribution in the composite and a uniform hydrophobic surface with an edge wetting angle of more than 130°. The effect of increasing the porosity of composites with the introduction of fluoroplastic matrices in the amount of up to 10 wt. % is described.