Enhancing the mechanical and electrical conductivity of copper matrix composites through grafting carbonized polymer dots (CPD) onto carbon nanotube surfaces

Tailoring the structural design of reinforcement is an effective strategy to attain the homogeneous dispersion and robust interface bonding in carbon nanotubes reinforced copper (CNTs/Cu) composites. Herein, a novel zero-dimensional carbonized polymer dots (CPD) was synthesized and grafted onto the CNTs surfaces via a typical one-step hydrothermal method. The resultant reinforcement, CPD@CNTs, exhibited good dispersibility due to the abundant polar functional groups on CPD. Furthermore, the interface adhesion was also ameliorated by means of the in-situ formed Cu2O transient phase. The CPD@CNTs/Cu composite shows outstanding mechanical performances, the yield strength and tensile strength had increased to 269 MPa and 308 MPa, while maintained excellent ductility (43 %). Moreover, the electrical conductivity of the composite remains at a high level of 95.3 %IACS. Our findings suggest that adjusting the structural configuration of reinforcement is a feasible approach to optimize dispersion and interfacial structure.