Exploring PTFE-free solutions as sustainable wear-resistant eco-polymers

Polytetrafluoroethylene (PTFE) is a widely utilised polymer in tribological applications (e.g., seals, sliding bearings, and gears), prized for its exceptionally low friction, self-lubricating properties, and high chemical and thermal stability. However, as a per- and polyfluoroalkyl substance (PFAS), its use is a major source of environmental pollution from industrial and consumer products. Certain PFAS compounds are also associated with carcinogenic and toxic effects, which necessitate a critical and urgent search for sustainable and safer alternatives. Still, the challenge lies in identifying materials that can replicate PTFE's unique combination of favourable properties, since no direct substitute polymer material currently exists. This research project, known as SWEEP (Exploring PTFE-free solutions as sustainable wear-resistant eco-polymers), directly addresses this issue by comprehensively investigating the tribological performance of a series of potential PTFE-free substitute materials, including high-performance thermoplastics and specifically engineered composites. The study employs a multi-faceted experimental approach, combining both lab-scale and component-level testing, to analyse the friction, wear, thermal response, and surface degradation of these alternative materials under a broad range of pressure-velocity (P × V) conditions. The investigation includes a detailed analysis of wear mechanisms, changes in surface topography, and the characteristics of wear particle generation and transfer film formation. As a result, this research provides crucial and fundamental insights into the tribological behaviour and characterisation of these PTFE-free alternatives, while establishing a robust framework for material ranking and evaluation. The eventual findings will be invaluable for the effective selection of polymer sliding elements and tribotechnical components, supporting the development of sustainable, high-performance solutions for various industrial sectors. The project represents a significant step towards reducing the reliance on PFAS-based materials, thereby contributing to both environmental protection and human health.