Nano-Clay-Stabilized Water-in-Oil Colloidal Pickering Emulsions as Thixotropic Lubricant

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Kumar, Arun, Yadav, Rahul, Joshi, Yogesh M., Singh, Manjesh K.
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911672108580864
author Kumar, Arun
Yadav, Rahul
Joshi, Yogesh M.
Singh, Manjesh K.
author_facet Kumar, Arun
Yadav, Rahul
Joshi, Yogesh M.
Singh, Manjesh K.
contents The limitations of conventional mineral oil-based lubricants motivate the development of environmentally benign emulsions capable of providing lubrication and heat dissipation in demanding applications. In this study, nano-organoclay (Garamite 1958)-stabilized thixotropic water-in-oil Pickering emulsions are developed using sunflower oil as the base. The rheological and tribological properties of the emulsion system are systematically examined. Rheological findings reveal a pronounced increase in yield stress, shear thinning and thixotropic behavior on increasing Garamite loading percentage in the emulsion. The tribological performance is assessed against dry, water, and oil-lubricated conditions for a steel-steel interface under high contact pressure. The findings indicate that the tribological performance is significantly influenced by the microstructure and thixotropic behavior of the emulsions. The emulsion with the optimal nano-clay concentration demonstrates approximately 41\% and 84\% lower friction and approximately 80\% and 96\% lower wear than oil and water, respectively. The emulsion exhibits sensitivity to the sliding direction and displays load-responsive friction behavior with a memory effect owing to the reversible structuring of the clay-droplet network. This superior performance is attributed to the combined effects of thixotropy, anisotropic nanoclay morphology, and stable droplet armoring, which form a robust and adaptive interfacial film. This study advances the understanding of Pickering emulsions in metallic tribosystems by correlating the microstructure and rheology with tribological performance, thereby facilitating the design of high-performance, smart, and eco-conscious lubricants for metallic systems.
format Preprint
id arxiv_https___arxiv_org_abs_2605_11004
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Nano-Clay-Stabilized Water-in-Oil Colloidal Pickering Emulsions as Thixotropic Lubricant
Kumar, Arun
Yadav, Rahul
Joshi, Yogesh M.
Singh, Manjesh K.
Soft Condensed Matter
The limitations of conventional mineral oil-based lubricants motivate the development of environmentally benign emulsions capable of providing lubrication and heat dissipation in demanding applications. In this study, nano-organoclay (Garamite 1958)-stabilized thixotropic water-in-oil Pickering emulsions are developed using sunflower oil as the base. The rheological and tribological properties of the emulsion system are systematically examined. Rheological findings reveal a pronounced increase in yield stress, shear thinning and thixotropic behavior on increasing Garamite loading percentage in the emulsion. The tribological performance is assessed against dry, water, and oil-lubricated conditions for a steel-steel interface under high contact pressure. The findings indicate that the tribological performance is significantly influenced by the microstructure and thixotropic behavior of the emulsions. The emulsion with the optimal nano-clay concentration demonstrates approximately 41\% and 84\% lower friction and approximately 80\% and 96\% lower wear than oil and water, respectively. The emulsion exhibits sensitivity to the sliding direction and displays load-responsive friction behavior with a memory effect owing to the reversible structuring of the clay-droplet network. This superior performance is attributed to the combined effects of thixotropy, anisotropic nanoclay morphology, and stable droplet armoring, which form a robust and adaptive interfacial film. This study advances the understanding of Pickering emulsions in metallic tribosystems by correlating the microstructure and rheology with tribological performance, thereby facilitating the design of high-performance, smart, and eco-conscious lubricants for metallic systems.
title Nano-Clay-Stabilized Water-in-Oil Colloidal Pickering Emulsions as Thixotropic Lubricant
topic Soft Condensed Matter
url https://arxiv.org/abs/2605.11004