ABSTRACT Polyurethane as a high‐performance polymer material characterized by high toughness, corrosion resistance, and good wear resistance can be widely used in bearing applications. However, under water‐lubricated conditions, the inherently weak hydrophilicity of polyurethane surfaces limits the formation of a stable hydrated lubrication layer, thereby restricting their tribological performance. To overcome this limitation, sulfonate groups‐containing polyurethane ionomers were synthesized via condensation polymerization, endowing the material surface with a negative charge. Specifically, the sulfonic acid group can adsorb hydrated cations through electrostatic action to form a hydrated lubrication film on the surface, which can effectively improve the material's tribological performance. The friction coefficients of polyurethane ionomer with TBAB‐BES molar ratio of 3% (PUI‐3) were significantly reduced when a 3 wt% NaCl solution was used as the lubricant. When the sliding speed was 0.01 m/s, the coefficient of friction for PUI‐3 was 0.053, achieving a 60% reduction in friction coefficient. Furthermore, the PUI‐3 with SO 3 − exhibited both excellent mechanical properties and water resistance. This work provides a new approach to improving the tribological properties of polyurethane materials in marine environments.
Ma et al. (Fri,) studied this question.