Amino functionalization of graphene/graphene-like MoSe₂ hybrids as lubricant additives for bismaleimide composites: Preparation, mechanical and tribological properties

Amine functionalization of graphene/graphene-like MoSe₂ (NH₂-rGO/MoSe₂) hybrid nanosheets were synthesized by a facile hydrothermal method. Then, as lubricant additives, the hybrids were doped into bismaleimide (BMI) matrix to reinforce the mechanical and tribological properties of BMI composites. Graphene-like MoSe₂ was introduced into rGO to prevent re-stacking of the layers. The microstructure of NH₂-rGO/MoSe₂ was also characterized. When the content of NH₂-rGO/MoSe₂ was 0.6 wt.%, the composite could achieve the highest impact and flexural strengths of 19.3 kJ/m² and 167.2 MPa, respectively. For the 0.4 wt.% NH₂-rGO/MoSe₂/BMI composite, it reached the minimum values for coefficient of friction and volume wear rate of 0.22 and 2.03 × 10⁻⁶ mm³/(N·m), decreased by 47.6% and 87.6% in comparison with those of pure BMI, respectively. The NH₂-rGO/MoSe₂ hybrids, acting as solid lubricants, played a key role in the enhanced toughness of the composites and interfacial strength between BMI matrix and filler. Thus, the improved tribological properties of the NH₂-rGO/MoSe₂/BMI composites were obtained.