Researchers tested how adding different sizes of graphene nanoplatelets to a composite material affects its ability to withstand impacts. They used two sizes of graphene particles and different resin viscosities in making composite plates of varying thicknesses. Results showed that using 30 μm graphene particles increased the energy absorbed by the composite, especially in thicker plates. However, using 5 μm particles had a negative impact on both peak forces and absorbed energy. The size of the graphene particles significantly influenced the impact response of the composite laminates.