Saved in:
Bibliographic Details
Main Authors: da Rocha, Jose Henrique Rodrigues, Manuel, Julio Gabriel de Falco, Bombard, Antonio Jose Faria
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2403.19774
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929295150022656
author da Rocha, Jose Henrique Rodrigues
Manuel, Julio Gabriel de Falco
Bombard, Antonio Jose Faria
author_facet da Rocha, Jose Henrique Rodrigues
Manuel, Julio Gabriel de Falco
Bombard, Antonio Jose Faria
contents Magnetorheological fluids (MRF) are smart composite materials that, under an external magnetic field, show a reversible solid-liquid transition in less than 10 ms. This study aimed to evaluate which organoclays would jellify a synthetic oil for the formulation of MRF. Three dispersant additives for carbonyl iron powder were evaluated. Fifteen different gelling additives from four clay families, bentonites, hectorites, montmorillonites, and mixed mineral thixotropes (MMT), were dispersed in oil only, keeping the same concentration, without iron particles. The gels were then tested through amplitude and frequency sweeps in oscillatory rheometry to evaluate their viscoelastic behavior. All the MRFs were prepared using carbonyl iron powder HS in oil gels with the same organoclay. All three dispersant additives showed a thixotropic recovery above 100% in the three-interval test. Regarding the dispersibility after one year, the MRF formulations with octan-1-amine and lecithin were reproved, as they reached normal force peaks of 19 and 24 N, while the work was 28 and 415 mJ, respectively. The best MRF was formulated with octan-1-ol, and resulted in a normal force of 0.33 N and 3.4 mJ at 35 mm of vane penetration. Therefore, we conclude that the MRF with octan-1-ol and montmorillonite #6 showed a better balance between thixotropy, MR effect, and, above all, good redispersibility.
format Preprint
id arxiv_https___arxiv_org_abs_2403_19774
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Synthetic Oil Gels With Organoclays In The Formulation Of Magnetorheological Fluids
da Rocha, Jose Henrique Rodrigues
Manuel, Julio Gabriel de Falco
Bombard, Antonio Jose Faria
Soft Condensed Matter
Magnetorheological fluids (MRF) are smart composite materials that, under an external magnetic field, show a reversible solid-liquid transition in less than 10 ms. This study aimed to evaluate which organoclays would jellify a synthetic oil for the formulation of MRF. Three dispersant additives for carbonyl iron powder were evaluated. Fifteen different gelling additives from four clay families, bentonites, hectorites, montmorillonites, and mixed mineral thixotropes (MMT), were dispersed in oil only, keeping the same concentration, without iron particles. The gels were then tested through amplitude and frequency sweeps in oscillatory rheometry to evaluate their viscoelastic behavior. All the MRFs were prepared using carbonyl iron powder HS in oil gels with the same organoclay. All three dispersant additives showed a thixotropic recovery above 100% in the three-interval test. Regarding the dispersibility after one year, the MRF formulations with octan-1-amine and lecithin were reproved, as they reached normal force peaks of 19 and 24 N, while the work was 28 and 415 mJ, respectively. The best MRF was formulated with octan-1-ol, and resulted in a normal force of 0.33 N and 3.4 mJ at 35 mm of vane penetration. Therefore, we conclude that the MRF with octan-1-ol and montmorillonite #6 showed a better balance between thixotropy, MR effect, and, above all, good redispersibility.
title Synthetic Oil Gels With Organoclays In The Formulation Of Magnetorheological Fluids
topic Soft Condensed Matter
url https://arxiv.org/abs/2403.19774