Study the application of polydopamine preparation technology in the interface modification of phthalonitrile composite

Polydopamine (PDA), recognized for its exceptional adhesion and high-temperature resistance, serves as an effective sizing agent in demanding composite material production. This study explores the application of PDA as an interface adhesive for carbon fiber-reinforced high-temperature phthalonitrile (PN) composites (CFRPN), assessing the effects of two PDA synthesis methods—electrochemical and solution oxidation—on interfacial modification. The electrochemical method uniformly fills grooves on CF surfaces, creating an optimal interface layer , yet it encounters challenges in bulk, multi-layer fiber processing . Conversely, the solution oxidation method, despite less uniform PDA distribution, exhibits greater consistency in batch processing and significantly enhances the interlaminar shear strength of CFRPN, outperforming the electrochemical method in mechanical enhancements. Given its simplicity and reduced equipment requirements, the solution oxidation method offers considerable potential for broader engineering applications .