Carbon fibre surface modification facilitated by silver-catalysed radical decarboxylation

A silver catalysed radical decarboxylation process was used to graft a copolymer (4 : 1; methylacrylate/acrylic acid) onto short carbon fibres. Surface grafting was confirmed by XPS, SEM and TGA, suggesting that the polymer accounted for 10% of the modified materials mass. Incorporation of these surface enhanced carbon fibres into an epoxy resin gave composites demonstrating an increase in ductility and a clear change in failure mode from adhesive, at the fibre-matrix interface, to cohesive, within the matrix polymer itself.