Temperature effect on mechanical strength and frictional properties of polytetrafluoroethylene-based core-shell nanocomposites

• Polytetrafluoroethylene (PTFE) has shown an outstanding lubricity as a solid lubricant, but its application is limited due to its low-mechanical strength and high-wear rate. In this study, core-shell nanoparticles were synthesized using PTFE as the core and polymethylmethacrylate (PMMA) as the shell. The formed core-shell nanocomposites by leveraging the core-shell nanoparticles as basic structural units exhibit remarkable enhancement on uniformity, tensile strength, and wear resistance, compared to mechanically mixed composites with the same composition. Our experiments demonstrated the following results: (1) Owing to the excellent uniformity, the maximum tensile strength of core-shell nanocomposites was 62 MPa, three times higher than that of mechanically mixed composites. (2) The composite matrix formed by PMMA shell had better reinforcement and protection effect on inner PTFE phase, resulting in a reduced wear rate of 0.3 × 10−5 mm3/(N m), one order of magnitude lower than that of mechanically mixed composites. (3) The friction coefficient and interfacial mechanical properties of the core-shell nanocomposites at different temperatures have been systematically studied to get insights into lubrication mechanisms. It is proved that the temperature can decrease the modulus and increase the interfacial adhesion as well as the loss tangent of the core-shell nanocomposites, thus affecting the lubrication properties in multiple ways. 

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Tribologi (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Tribology (hsv//eng)

Nyckelord

Core shell nanoparticles

Core-shell nanocomposites

Friction

Friction coefficients

Frictional properties

Interfacial adhesions

Interfacial mechanical properties

Lubrication mechanism

Lubrication property

Nanocomposites

Nanoparticles

Polytetrafluoroethylene (PTFE)

Polytetrafluoroethylenes

Shells (structures)

Solid lubricants

Synthesis (chemical)

Tensile strength

Wear of materials

Wear resistance

emulsion polymerization

friction

wear and lubrication

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)