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Tribology Letters

, 62:24 | Cite as

Effect of Alkyl Chain Length on the Orientational Behavior of Liquid Crystals Nano-Film

  • Ming Gao
  • Liran MaEmail author
  • Jianbin Luo
Original Paper

Abstract

Different homologues of cyanobiphenyl liquid crystals (CB LC) (nCB with n = 5, 6, 7) present an interesting and novel material system. So far, their orientational behavior at nanoscale has not been extensively investigated yet. Here, we utilized a self-established in situ ball-on-disk testing platform equipped with polarized Raman spectroscopy, to study the ordering performance of nCB LCs confined as a nano-thin lubricating film. The results demonstrated that both external condition as shear velocity and internal molecular alkyl length dramatically affect the ordering process of nCB LC nano-lubricating film, consequently the degree of anisotropy. A simple model, along with detailed physical analysis, has been proposed to explain the observed phenomena. Our findings may provide new insights into controlling the alignment of LCs during lubricating.

Keywords

Nanotribology Liquid crystal Nano-lubricating film Raman spectroscopy 

Notes

Acknowledgments

The work was financially supported by the National Natural Science Foundation of China (51305225), the National Key Basic Research Program of China (2013CB934200), Research Fund of the Tsinghua University (20131089320).

Supplementary material

11249_2016_663_MOESM1_ESM.docx (178 kb)
Supplementary material 1 (DOCX 177 kb)

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.State Key Laboratory of TribologyTsinghua UniversityBeijingChina

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