ELECTROCOATING OF CARBON-FIBERS WITH POLYMERS .3. ELECTROCOPOLYMERIZATION OF POLYFUNCTIONAL MONOMERS

The electrocopolymerization of glycidyl methacrylate and methyl methacrylate is described. The compositions of the monomer-electrolyte solution and the parameters of the polymerization coating process that provide formation of thin, even coatings on carbon fibres were determined. The mole fraction of glycidyl methacrylate in the synthesized copolymers was calculated from glass transition temperature, Fourier-transform infra-red and nuclear magnetic resonance determinations. The mechanism of the electrochemical reaction, which leads to grafting of the copolymer onto the carbon fibre surface, is discussed. Composites from carbon fibres coated with the mentioned copolymers showed improved fracture energy during delamination (60-100%) and improved interlaminar shear strength (approximately 20%) in comparison with specimens from uncoated fibres.