Enhancing friction in rubber treads under lubrication: A review

Rubber products used in shoe soles and tires require high friction, especially under lubrication, to ensure safety in daily life. The frictional behavior of rubber under lubrication is influenced by various parameters, including the properties of the rubber tread, the lubricant, the mating surface, and the sliding conditions. The effects of these parameters on friction have been investigated, but the mechanisms for enhancing friction under lubrication have not been studied systematically. This review provides a summary of the methods used to enhance rubber friction under lubrication, including optimizing the tread groove geometry to improve drainage, increasing the contact area, preventing liquid from flowing into the contact interface, increasing hysteresis friction, and controlling the surface free energy of rubber to promote dewetting. Additionally, suction-based attachment is emphasized as an effective mechanism for liquid-covered surfaces. Integrating these approaches may significantly advance the design of high-friction rubber treads, enabling the development of materials that maintain high friction regardless of lubrication conditions.