Imperial College London
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Dr James P. Ewen

Faculty of Engineering, Department of Mechanical Engineering

RAEng Research Fellow
 
 
 
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Contact

 

j.ewen Website

 
 
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Location

 

462City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Ayestaran:2021:10.1038/s42004-021-00615-x,
author = {Ayestaran, Latorre C and Moore, J and Remias, J and Spikes, H and Dini, D and Ewen, J},
doi = {10.1038/s42004-021-00615-x},
journal = {Communications Chemistry},
pages = {1--11},
title = {Mechanochemistry of phosphate esters confined between sliding iron surfaces},
url = {http://dx.doi.org/10.1038/s42004-021-00615-x},
volume = {4},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The molecular structure of lubricant additives controls not only their adsorption and dissociation behaviour at the nanoscale, but also their ability to reduce friction and wear at the macroscale.  Here,  we  show  using  nonequilibrium  molecular  dynamics  simulations  with  a reactive force field that tri(s-butyl)phosphate dissociates much faster than tri(n-butyl)phosphate  when  heated  and  compressed  between  sliding  iron  surfaces.  For  both molecules, dissociative chemisorption proceeds through cleavage of carbon−oxygen bonds. The dissociation rate increases exponentially with temperature and stress. When the rate−temperature−stress  data  are  fitted  with  the  Bell  model,  both  molecules  have  similar activation energies and activation volumes and the higher reactivity of tri(s-butyl)phosphate is due  to  a  larger  pre-exponential  factor.  These  observations  are  consistent  with  experiments using the antiwear additive zinc dialkyldithiophosphate. This study represents a crucial step towards  the  virtual  screening  of  lubricant  additives  with  different  substituents  to  optimise tribological performance.
AU  - Ayestaran,Latorre C
AU  - Moore,J
AU  - Remias,J
AU  - Spikes,H
AU  - Dini,D
AU  - Ewen,J
DO  - 10.1038/s42004-021-00615-x
EP  - 11
PY  - 2021///
SN  - 2399-3669
SP  - 1
TI  - Mechanochemistry of phosphate esters confined between sliding iron surfaces
T2  - Communications Chemistry
UR  - http://dx.doi.org/10.1038/s42004-021-00615-x
UR  - https://www.nature.com/articles/s42004-021-00615-x
UR  - http://hdl.handle.net/10044/1/92997
VL  - 4
ER  -
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