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Title: Poly(alkyl methacrylate) Brush-Grafted Silica Nanoparticles as Oil Lubricant Additives: Effects of Alkyl Pendant Groups on Oil Dispersibility, Stability, and Lubrication Property

Abstract

This paper reports on the synthesis of a series of poly(alkyl methacrylate) brush-grafted, 23 nm silica nanoparticles (hairy NPs) and the study of the effect of alkyl pendant length on their use as oil lubricant additives for friction and wear reduction. The hairy NPs were prepared by surface-initiated reversible addition–fragmentation chain transfer polymerization from trithiocarbonate chain transfer agent (CTA)-functionalized silica NPs in the presence of a free CTA. We found that hairy NPs with sufficiently long alkyl pendant groups (containing >8 carbon atoms, such as 12, 13, 16, and 18 in this study) could be readily dispersed in poly(alphaolefin) (PAO), forming clear, homogeneous dispersions, and exhibited excellent stability at low and high temperatures as revealed by visual inspection and dynamic light scattering studies. Whereas poly(n-hexyl methacrylate) hairy NPs cannot be dispersed in PAO under ambient conditions or at 80 °C, interestingly, poly(2-ethylhexyl methacrylate) hairy NPs can be dispersed in PAO at 80 °C but not at room temperature, with a reversible clear-to-cloudy transition observed upon cooling. High-contact-stress ball-on-flat reciprocating sliding tribological tests at 100 °C showed significant reductions in both the coefficient of friction (up to 38%) and wear volume (up to 90% for iron flat) for transparent, homogeneous dispersionsmore » of hairy NPs in PAO at a concentration of 1.0 wt % compared with neat PAO. Finally, the formation of a load-bearing tribofilm at the rubbing interface was confirmed using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy.« less

Authors:
 [1];  [1];  [1];  [2];  [2]; ORCiD logo [3]; ORCiD logo [4]; ORCiD logo [1]
  1. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry
  2. Univ. of California, Merced, CA (United States). Dept. of Mechanical Engineering
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
  4. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Science Division
Publication Date:
Research Org.:
Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
Contributing Org.:
Univ. of California, Merced, CA (United States)
OSTI Identifier:
1376473
Alternate Identifier(s):
OSTI ID: 1430640
Grant/Contract Number:  
AC05-00OR22725; EE0006925
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ACS Applied Materials and Interfaces
Additional Journal Information:
Journal Volume: 9; Journal Issue: 29; Journal ID: ISSN 1944-8244
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; antiwear; colloidal stability; friction reduction; hairy nanoparticles; lubricant additives; oil solubility; surface-initiated RAFT polymerization

Citation Formats

Seymour, Bryan T., Wright, Roger A. E., Parrott, Alexander C., Gao, Hongyu, Martini, Ashlie, Qu, Jun, Dai, Sheng, and Zhao, Bin. Poly(alkyl methacrylate) Brush-Grafted Silica Nanoparticles as Oil Lubricant Additives: Effects of Alkyl Pendant Groups on Oil Dispersibility, Stability, and Lubrication Property. United States: N. p., 2017. Web. doi:10.1021/acsami.7b06714.
Seymour, Bryan T., Wright, Roger A. E., Parrott, Alexander C., Gao, Hongyu, Martini, Ashlie, Qu, Jun, Dai, Sheng, & Zhao, Bin. Poly(alkyl methacrylate) Brush-Grafted Silica Nanoparticles as Oil Lubricant Additives: Effects of Alkyl Pendant Groups on Oil Dispersibility, Stability, and Lubrication Property. United States. https://doi.org/10.1021/acsami.7b06714
Seymour, Bryan T., Wright, Roger A. E., Parrott, Alexander C., Gao, Hongyu, Martini, Ashlie, Qu, Jun, Dai, Sheng, and Zhao, Bin. 2017. "Poly(alkyl methacrylate) Brush-Grafted Silica Nanoparticles as Oil Lubricant Additives: Effects of Alkyl Pendant Groups on Oil Dispersibility, Stability, and Lubrication Property". United States. https://doi.org/10.1021/acsami.7b06714. https://www.osti.gov/servlets/purl/1376473.
@article{osti_1376473,
title = {Poly(alkyl methacrylate) Brush-Grafted Silica Nanoparticles as Oil Lubricant Additives: Effects of Alkyl Pendant Groups on Oil Dispersibility, Stability, and Lubrication Property},
author = {Seymour, Bryan T. and Wright, Roger A. E. and Parrott, Alexander C. and Gao, Hongyu and Martini, Ashlie and Qu, Jun and Dai, Sheng and Zhao, Bin},
abstractNote = {This paper reports on the synthesis of a series of poly(alkyl methacrylate) brush-grafted, 23 nm silica nanoparticles (hairy NPs) and the study of the effect of alkyl pendant length on their use as oil lubricant additives for friction and wear reduction. The hairy NPs were prepared by surface-initiated reversible addition–fragmentation chain transfer polymerization from trithiocarbonate chain transfer agent (CTA)-functionalized silica NPs in the presence of a free CTA. We found that hairy NPs with sufficiently long alkyl pendant groups (containing >8 carbon atoms, such as 12, 13, 16, and 18 in this study) could be readily dispersed in poly(alphaolefin) (PAO), forming clear, homogeneous dispersions, and exhibited excellent stability at low and high temperatures as revealed by visual inspection and dynamic light scattering studies. Whereas poly(n-hexyl methacrylate) hairy NPs cannot be dispersed in PAO under ambient conditions or at 80 °C, interestingly, poly(2-ethylhexyl methacrylate) hairy NPs can be dispersed in PAO at 80 °C but not at room temperature, with a reversible clear-to-cloudy transition observed upon cooling. High-contact-stress ball-on-flat reciprocating sliding tribological tests at 100 °C showed significant reductions in both the coefficient of friction (up to 38%) and wear volume (up to 90% for iron flat) for transparent, homogeneous dispersions of hairy NPs in PAO at a concentration of 1.0 wt % compared with neat PAO. Finally, the formation of a load-bearing tribofilm at the rubbing interface was confirmed using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy.},
doi = {10.1021/acsami.7b06714},
url = {https://www.osti.gov/biblio/1376473}, journal = {ACS Applied Materials and Interfaces},
issn = {1944-8244},
number = 29,
volume = 9,
place = {United States},
year = {2017},
month = {7}
}

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Works referenced in this record:

The History and Mechanisms of ZDDP
journal, October 2004


A review of zinc dialkyldithiophosphates (ZDDPS): characterisation and role in the lubricating oil
journal, June 2001


On the Mechanism of ZDDP Antiwear Film Formation
journal, June 2016


Antiwear Performance and Mechanism of an Oil-Miscible Ionic Liquid as a Lubricant Additive
journal, February 2012


Tribological performance of nanoparticles as lubricating oil additives
journal, August 2016


Preparation of Ni Nanoparticles and Evaluation of Their Tribological Performance as Potential Additives in Oils
journal, October 1999


Study of friction reduction by nanocopper additives to motor oil
journal, January 2002


Tribological properties of lubricant additives of Fe, Cu and Co nanoparticles
journal, April 2013


Ultralow-friction and wear properties of IF-WS2 under boundary lubrication
journal, April 2005


The tribological behaviour of ZnO nanoparticles as an additive to PAO6
journal, August 2006


Nanoscale Organic−Inorganic Hybrid Lubricants
journal, March 2011


Friction Modifier Additives
journal, September 2015


Synthesis of Nanocomposite Organic/Inorganic Hybrid Materials Using Controlled/“Living” Radical Polymerization
journal, October 2001


Polymer Brushes via Surface-Initiated Controlled Radical Polymerization: Synthesis, Characterization, Properties, and Applications
journal, November 2009


Stimuli-triggered phase transfer of polymer-inorganic hybrid hairy particles between two immiscible liquid phases
journal, July 2014


Preparation of Structurally Well-Defined Polymer−Nanoparticle Hybrids with Controlled/Living Radical Polymerizations
journal, August 1999


Fabrication of Ordered Arrays of Gold Nanoparticles Coated with High-Density Polymer Brushes
journal, June 2003


Controlled Synthesis of Polymer Brushes by “Living” Free Radical Polymerization Techniques
journal, March 1999


Oil-Soluble Polymer Brush Grafted Nanoparticles as Effective Lubricant Additives for Friction and Wear Reduction
journal, June 2016


Reversible Addition Fragmentation Chain Transfer (RAFT) Polymerization from Unprotected Cadmium Selenide Nanoparticles
journal, October 2004


A Versatile Method To Prepare RAFT Agent Anchored Substrates and the Preparation of PMMA Grafted Nanoparticles
journal, May 2006


Living Free-Radical Polymerization by Reversible Addition−Fragmentation Chain Transfer:  The RAFT Process
journal, August 1998


Advances in RAFT polymerization: the synthesis of polymers with defined end-groups
journal, September 2005


Thermally Reversible Physically Cross-Linked Hybrid Network Hydrogels Formed by Thermosensitive Hairy Nanoparticles
journal, August 2016


End group removal and modification of RAFT polymers
journal, January 2010


Thermolysis of RAFT-Synthesized Polymers. A Convenient Method for Trithiocarbonate Group Elimination
journal, June 2005


Lubrication with Oil-Compatible Polymer Brushes
journal, January 2012


Works referencing / citing this record:

Dispersion of Nanoparticles in Lubricating Oil: A Critical Review
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Statistical copolymerization of N-vinyl-pyrrolidone and alkyl methacrylates via RAFT: reactivity ratios and thermal analysis
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Frictional performance evaluation of sliding surfaces lubricated by zinc - oxide nano-additives
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Practical use of polymer brushes in sustainable energy applications: interfacial nanoarchitectonics for high-efficiency devices
journal, January 2019