Soft/Hard-Coupled Amphiphilic Polymer Nanospheres for Water Lubrication
Zhaoxia Li1,2, Shuanhong Ma1, Ga Zhang1
1State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics , Chinese Academy of Sciences , Lanzhou 730000 , China.
ACS Applied Materials & Interfaces
|February 23, 2018
Summary
Amphiphilic polymer nanospheres enhance water lubrication for Ti6Al4V alloy. These P(SPMA-co-St) nanospheres improve anti-wear properties by combining a rigid core with a soft, hydrating shell.
Area of Science:
- Materials Science
- Tribology
- Polymer Chemistry
Background:
- Titanium alloys like Ti6Al4V are crucial in various applications but require effective lubrication to prevent wear.
- Water lubrication presents challenges due to its limited inherent lubricating properties.
- Developing novel additives is essential to enhance the tribological performance of water-based lubricants.
Purpose of the Study:
- To synthesize amphiphilic polymer nanospheres of poly(3-sulfopropyl methacrylate potassium salt-co-styrene) [P(SPMA-co-St)].
- To evaluate their efficacy as water lubrication additives for improving the anti-wear behavior of Ti6Al4V alloy.
- To investigate the influence of nanosphere composition and concentration on tribological properties and propose an anti-wear mechanism.
Main Methods:
- Soap-free emulsion polymerization was employed to synthesize monodisperse P(SPMA-co-St) nanospheres.
- Tribological tests were conducted to assess friction coefficient and wear volume under varying conditions (monomer concentration, additive content, load, frequency).
- The structure-property relationship was analyzed, correlating the soft/hard coupling of nanospheres with lubrication performance.
Main Results:
- P(SPMA-co-St) nanospheres demonstrated superior anti-wear properties compared to pure polystyrene (PSt) in water lubrication.
- Optimal SPMA content reduced friction coefficient and wear volume, attributed to the hydrophilic hydration layer of PSPMA.
- A saturation concentration of 1 wt% polymer nanosphere additive achieved stable and low friction and wear.
Conclusions:
- The synthesized amphiphilic P(SPMA-co-St) nanospheres effectively reduce friction and wear in water lubrication.
- The combination of a rigid PSt core and a hydrophilic PSPMA shell is key to their lubricating performance.
- These nanospheres show significant potential for applications in water lubrication and biological lubrication systems.
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