Construction of dendritic polymers on carbon fiber surfaces to improve the interfacial bonding of carbon fiber/silicone rubber composites

Carbon fiber (CF) reinforced composite materials are highly sought after for their exceptional mechanical properties and functional capabilities, making them promising materials for applications in aerospace and other industries. In this study, we aimed to construct a medium modulus interfacial layer using the layer-by-layer construction (LBL) method. This was achieved by grafting rigid dendritic polymers onto the surface of the carbon fiber, with the branch density being adjustable based on the reaction time. The rigid branched structure of the dendritic polymer and the numerous functional groups provide physical entanglement and stronger mechanical bonding at the interface, great chemical bonding. This distinctive structure improves the interfacial compatibility of the composite and enhances its mechanical properties. Following treatment, the tensile properties of the fibres are increased by approximately 20 %, suggesting that the treatment process effectively repairs surface defects on the fiber. Compared to untreated carbon fiber composites, the tensile properties of CF-M-P3 have improved by approximately 11 %. Furthermore, the thermal weight loss of the composite material is significantly reduced due to the branching of its rigid dendritic structure. The weight loss percentage decreased from 16.84 % to 7.89 % after being held at a temperature of 350 °C for a duration of 4 h.