High-grip and hard-wearing graphene reinforced polyurethane coatings

Liquid polyurethane (PU) resins are used to form anti-slip surface coatings. In this work, we reinforce PU resin films with few-layer graphene (FLG) nanoparticles incorporated by high-shear mixing. This process gives excellent dispersion as evidenced by optical and X-ray tomography. The FLG does not appreciably change the tensile strength or Shore hardness of the PU, but we report modest increase of 10% in tear strength and Young's modulus, accompanied by a similar decrease in elongation to failure. However, significant improvement of over 100% is observed in the abrasion resistance. At the same time, we report a 25% increase in the coefficient of static friction and 200% increase in the coefficient of dynamic friction. These results, taken together, suggests that graphene can significantly improve the grip and durability of PU anti-slip coatings, without significantly affecting the other mechanical properties of the coating.