Investigating the frictional behavior of polydimethylsiloxane (PDMS) with well-controlled roughness in complex fluids is important for biological and chemical applications. In this paper, we adopt an aqueous solution of a charged, hydrophobic acrylate copolymer as a lubricant. The scaling laws between the coefficient of friction (CoF) and the roughness of PDMS, as well as the concentration of the polymer solution in different lubrication regimes, are obtained. In the boundary lubrication regime, surface roughness and lubricant rheological behavior both remarkably influence the CoF. Moreover, the product of the CoF in the boundary regime and the velocity of the boundary-mixed transition is independent of roughness. A full lubricant film forms and shear thinning behavior dominates in the hydrodynamic lubrication regime. Frictional behavior in this tribological system has been successfully regulated. We hope to establish the optimal match of surface roughness and the rheological behavior of lubricant and unveil the mechanism behind the friction phenomenon.

研究在复杂流体中具有良好控制粗糙度的聚二甲基硅氧烷 (PDMS) 的摩擦行为对于生物和化学应用非常重要。在本文中，我们采用带电荷的疏水性丙烯酸酯共聚物的水溶液作为润滑剂。获得了摩擦系数 ( CoF ) 与 PDMS 粗糙度之间的缩放规律，以及不同润滑状态下聚合物溶液的浓度。在边界润滑状态下，表面粗糙度和润滑剂流变行为都显着影响CoF。此外，CoF的产物在边界状态中，边界混合过渡的速度与粗糙度无关。完整的润滑油膜形成，剪切变稀行为在流体动力润滑状态中占主导地位。该摩擦学系统中的摩擦行为已被成功调节。我们希望建立表面粗糙度和润滑剂流变行为的最佳匹配，并揭示摩擦现象背后的机制。