Tunable Friction Through Stimuli Responsive Hybrid Carbon Microspheres


Oak S., Pashazanusi L., Sengel S. B. , Omarova M., Hemstock J. L. , He W., ...Daha Fazla

LANGMUIR, cilt.35, ss.15849-15854, 2019 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 35 Konu: 48
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1021/acs.langmuir.9b01820
  • Dergi Adı: LANGMUIR
  • Sayfa Sayıları: ss.15849-15854

Özet

We explore the use of poly(N-isopropylacrylamide) (PNIPAm)-grafted carbon microspheres (CM) dispersed in water as a stimulus-responsive lubricant. A critical concentration between 3 and 5 mg/mL of PNIPAm-grafted CM is needed to achieve low friction (coefficient of friction similar to 0.04) at room temperature between borosilicate and silicon surfaces. An increase in the temperature of the system above the lower critical solution temperature (LCST) causes the aggregation of PNIPAm-grafted CM which leads to an increase in friction forces. The process is not immediately reversible unless the lubricant is sonicated so as to redisperse the aggregates. This work provides insight into the rolling friction mechanism and demonstrates the importance of particle singlets in achieving effective lubrication through a rolling mechanism.