Tribology Letters

, Volume 49, Issue 1, pp 169–178 | Cite as

Self-lubricating SU-8 Nanocomposites for Microelectromechanical Systems Applications

  • Prabakaran Saravanan
  • Nalam Satyanarayana
  • Sujeet K. Sinha
Original Paper


SU-8 is an industrially useful photoresist polymer for micro-fabrication because of its unique UV-sensitive curing property. It is also used as a structural material for micro-machines such as micro-electro mechanical systems (MEMS). However, it has poor tribological and mechanical properties which make SU-8 inferior to Si, the mainstay MEMS material today. In this paper, we report the fabrication of SU-8 nanocomposites which are self-lubricating and have better mechanical properties. The liquid lubricant i.e., perfluoropolyether (PFPE) and nanoparticles such as SiO2, CNTs, and graphite were added into SU-8 for this purpose. These self-lubricating SU-8 + PFPE and SU-8 + PFPE + nanoparticle composites have shown a reduction in the initial coefficient of friction by ~6–9 times and increased wear life by more than four orders of magnitude. The mechanical properties such as the elastic modulus and the hardness have increased by ~1.4 times. These SU-8 nanocomposites can be used as a self-lubricating structural material for MEMS applications requiring no external lubrication. As well, these nanocomposites can find applications in many tribological components of traditional machines.


Lubrication Polymer Self-lubrication MEMS 


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Prabakaran Saravanan
    • 1
  • Nalam Satyanarayana
    • 1
  • Sujeet K. Sinha
    • 1
  1. 1.Department of Mechanical EngineeringNational University of SingaporeSingaporeSingapore

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