Interfacial enhancement of carbon fiber composites by growing TiO2 nanowires onto amine-based functionalized carbon fiber surface in supercritical water

A novel amine-based functionalization method was developed to improve the interfacial adhesion between TiO 2 NWs and CFs in supercritical water. The microstructure, morphology and mechanical properties of CFs were investigated. It was found that introducing hexamethylenetetramine (HMTA) dendrimers and branched polyethyleneimine (PEI) on CF could increase significantly the adhesion strength between CF and TiO 2 NWs and their interfacial shear strength with epoxy resin, and the order is CF-PEI-TiO 2 NWs   >   CF-HMTA-TiO 2 NWs   >   CF-COOH-TiO 2 NWs   >   CF-TiO 2 NW. Meanwhile, the reinforcing mechanisms and interfacial failure modes have also been discussed. We believe that these effective methods may provide theoretical foundation for the preparation of high performance composite materials.