{"id":16459,"date":"2024-07-22T18:36:54","date_gmt":"2024-07-22T16:36:54","guid":{"rendered":"https:\/\/navier-lab.fr\/?page_id=16459"},"modified":"2024-09-06T10:29:29","modified_gmt":"2024-09-06T08:29:29","slug":"colloidal-suspensions-and-pastes","status":"publish","type":"page","link":"https:\/\/navier-lab.fr\/en\/research\/rheophysics-porous-media\/colloidal-suspensions-and-pastes\/","title":{"rendered":"Colloidal Suspensions and Pastes"},"content":{"rendered":"<p><section class=\"kc-elm kc-css-722926 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-207852 kc_col-sm-12 kc_column kc_col-sm-12\"><div class=\"kc-col-container\"><div class=\"kc-elm kc-css-439137\" style=\"height: 40px; clear: both; width:100%;\"><\/div>\n\t<div class=\"kc-elm kc-css-755301 kc_shortcode kc_video_play kc_video_wrapper\">\n\t\t\t\t\t\t\t\t<video width=\"400\" height=\"225.98870056497\" controls autoplay>\n\t\t\t\t<source src=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/09\/particle_beam_optical_tweezers-2.mp4\" type=\"video\/mp4\">\n\t\t\t\tYour browser does not support the video tag.\t\t\t<\/video>\n\n\t\t\t<\/div>\n\n<div class=\"kc-elm kc-css-289814\" style=\"height: 40px; clear: both; width:100%;\"><\/div><div class=\"kc-elm kc-css-344357 kc_text_block\"><\/p>\n<p style=\"text-align: center;\">Our research group studies the mechanical and physical properties of colloidal suspensions and pastes at the<em> particle<\/em> scale, from the ideal case of hard spheres to more complex cases involving rod-like particles (two-dimensional analogues of clay particles) and the addition of surfactants and polymer interacting with the particles. We combine numerical simulation and experimental tools, e.g. the <a href=\"https:\/\/navier-lab.fr\/en\/equipment-and-resources\/optical-tweezers\/\">optical tweezers setup<\/a>. We also examine the extrudability and three-dimensional printing of these materials at the macroscopic scale.<\/p>\n<p>\n<\/div><div class=\"kc-elm kc-css-954340\" style=\"height: 20px; clear: both; width:100%;\"><\/div><\/div><\/div><\/div><\/div><\/section><section class=\"kc-elm kc-css-537052 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-80682 kc_col-sm-4 kc_column kc_col-sm-4\"><div class=\"kc-col-container\"> <article class=\"sabbi-thumlinepost-card solitude-bg__x kc-elm kc-css-381238\"><figure class=\"sabbi-thumlinepost-card-figure\">\n                           <img loading=\"lazy\" decoding=\"async\" width=\"593\" height=\"500\" src=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/silica-beads-antoine-meb-square.jpg\" class=\"img-responsive img-thumpost\" alt=\"1\u00b5m silica beads as seen by a SEM\" srcset=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/silica-beads-antoine-meb-square.jpg 593w, https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/silica-beads-antoine-meb-square-300x253.jpg 300w\" sizes=\"auto, (max-width: 593px) 100vw, 593px\" \/>\n                          <\/figure><div class=\"sabbi-thumlinepost-card-meta\">\n                        <h2 class=\"info-box-title ht-5\">Rheology and aging of colloidal suspensions<\/h2><a href=\"#rheology-aging-colloidal-suspensions\" title=\"\" target=\"_self\" class=\"btn btn-unsolemn btn-action read-more\">Read More<\/a><\/div>\n                <\/article><\/div><\/div><div class=\"kc-elm kc-css-225325 kc_col-sm-4 kc_column kc_col-sm-4\"><div class=\"kc-col-container\"> <article class=\"sabbi-thumlinepost-card solitude-bg__x kc-elm kc-css-659424\"><figure class=\"sabbi-thumlinepost-card-figure\">\n                           <img loading=\"lazy\" decoding=\"async\" width=\"295\" height=\"250\" src=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2023\/11\/Printing.png\" class=\"img-responsive img-thumpost\" alt=\"Patterns observed during 3d printing of a yield-stress fluid at increasing speeds.\" \/>\n                          <\/figure><div class=\"sabbi-thumlinepost-card-meta\">\n                        <h2 class=\"info-box-title ht-5\">Three-dimensional printing of yield-stress fluids<\/h2><a href=\"#3d-printing-yield-stress-fluids\" title=\"Bubbly Media and Foams\" target=\"_self\" class=\"btn btn-unsolemn btn-action read-more\">Read More<\/a><\/div>\n                <\/article><\/div><\/div><div class=\"kc-elm kc-css-627406 kc_col-sm-4 kc_column kc_col-sm-4\"><div class=\"kc-col-container\"> <article class=\"sabbi-thumlinepost-card solitude-bg__x kc-elm kc-css-510258\"><figure class=\"sabbi-thumlinepost-card-figure\">\n                           <img loading=\"lazy\" decoding=\"async\" width=\"1094\" height=\"710\" src=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/colloidal-suspension-aging.png\" class=\"img-responsive img-thumpost\" alt=\"Numerical Simulation of an Aging Colloidal Suspension (top : particle positions, bottom : particle contacts)\" srcset=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/colloidal-suspension-aging.png 1094w, https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/colloidal-suspension-aging-300x195.png 300w, https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/colloidal-suspension-aging-1024x665.png 1024w, https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/colloidal-suspension-aging-768x498.png 768w\" sizes=\"auto, (max-width: 1094px) 100vw, 1094px\" \/>\n                          <\/figure><div class=\"sabbi-thumlinepost-card-meta\">\n                        <h2 class=\"info-box-title ht-5\">Numerical approaches for colloidal suspensions<\/h2><a href=\"#yield-stress-fluid-foam-stability\" title=\"Bubbly Media and Foams\" target=\"_self\" class=\"btn btn-unsolemn btn-action read-more\">Read More<\/a><\/div>\n                <\/article><\/div><\/div><\/div><\/div><\/section><section class=\"kc-elm kc-css-746391 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-524733 kc_col-sm-12 kc_column kc_col-sm-12\"><div class=\"kc-col-container\"><div class=\"kc-elm kc-css-797070\" style=\"height: 0px; clear: both; width:100%;\"><\/div>\n<div class=\"kc-elm kc-css-708593 divider_line\">\n\t<div class=\"divider_inner divider_line1\">\n\t\t\t<\/div>\n<\/div>\n<\/div><\/div><\/div><\/div><\/section><section id=\"rheology-aging-colloidal-suspensions\" class=\"kc-elm kc-css-599686 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-340410 kc_col-sm-12 kc_column kc_col-sm-12\"><div class=\"kc-col-container\"><div class=\"kc-elm kc-css-504163 kc_text_block\"><\/p>\n<h3>Rheology and aging of colloidal suspensions<\/h3>\n<p>\n<\/div><div class=\"kc-elm kc-css-877330 kc_text_block\"><\/p>\n<h5>X. Chateau, J. Goyon-Trohay, A. Lema\u00eetre, A. Aubel (PhD), C. Veillon (PhD)<\/h5>\n<h5>Collaborations : E. Furst (U. Delaware)<\/h5>\n<p>\n<\/div><div class=\"kc-elm kc-css-526991\" style=\"height: 10px; clear: both; width:100%;\"><\/div><div class=\"kc-elm kc-css-282161 kc_text_block\"><\/p>\n<p>\nSuspensions of micron-sized particles have complex rheological characteristics which typically include a yield stress under which they do not flow, the origin of which being unclear. We have evidenced that thixotropy in these materials occurs without any microstructural changes in these materials. Using a three-point flexural test on particle rods built using optical tweezers, we have shown that contacts between particles resist sliding and rolling motion. This resistance increases with the age of the contact. We have successfully described the macroscopic rheological properties of these materials from the contact properties between particles only using scalar functions of the suspension microstructure.<\/p>\n<p>\n<\/div><div class=\"kc-elm kc-css-260657\" style=\"height: 10px; clear: both; width:100%;\"><\/div><div class=\"kc-elm kc-css-294399 kc_text_block\"><\/p>\n<p>\nWe have then showed that adding a non-ionic surfactant to the suspension drastically modifies the rolling properties of the interparticle contacts <em>and<\/em> the bulk rheology of the suspension. The change in contact properties is attributed to surfactant adsorption at the particle surface, which transforms an adhesive contact resisting rolling motion into a non-adhesive contact. As in the case of the clean silica suspension, the excellent quantitative agreement between bulk tests and particle beam tests demonstrates that contact properties between grains control the global properties of the suspension. These results should lead us to reconsider our understanding of thixotropy in dense colloidal suspensions, paving the way to future advances in their formulation.<\/p>\n<p>\n<\/div><div class=\"kc-elm kc-css-27609\" style=\"height: 30px; clear: both; width:100%;\"><\/div>\n\t<div class=\"kc-elm kc-css-704184 kc_shortcode kc_video_play kc_video_wrapper\" data-video=\"https:\/\/vimeo.com\/811773976\" data-width=\"600\" data-height=\"338.98305084746\" data-fullwidth=\"\" data-autoplay=\"\" data-loop=\"yes\" data-control=\"yes\" data-related=\"\" data-showinfo=\"\" data-kc-video-mute=\"\">\n\t\t\t<\/div>\n\n<div class=\"kc-elm kc-css-233432 kc_text_block\"><\/p>\n<p style=\"text-align: center;\"><em>Credits : \u00c9cole Nationale des Ponts et Chauss\u00e9es &amp; Ingenius, the digital digest of the \u00c9cole.<br \/>\n<\/em><\/p>\n<p>\n<\/div><div class=\"kc-elm kc-css-170750\" style=\"height: 10px; clear: both; width:100%;\"><\/div>\n<div class=\"kc-elm kc-css-423448 divider_line\">\n\t<div class=\"divider_inner divider_line1\">\n\t\t\t<\/div>\n<\/div>\n<div class=\"kc-elm kc-css-384433 kc_text_block\"><\/p>\n<h4>References<\/h4>\n<div>\n<ul>\n<li><a href=\"https:\/\/doi.org\/10.1038\/s41563-020-0624-9\">Contact and macroscopic aging in colloidal suspensions<\/a>, F. Bonacci, X. Chateau, E. M. Furst, J. Goyon and A. Lemaitre<em>, Nature <\/em><em>Materials<\/em>, 19, 775-780 (2020).<\/li>\n<li><a href=\"https:\/\/doi.org\/10.1103\/PhysRevLett.128.018003\">Yield stress aging in attractive colloidal suspensions<\/a>, F. Bonacci, X. Chateau, E. M. Furst, J. Goyon and A. Lemaitre, <em>Physical <\/em><em>Review Letters<\/em> 128, 018003 (2022).<\/li>\n<li><a href=\"https:\/\/theses.fr\/2023UEFL2045\">Adjuvantation de suspensions mod\u00e8les : caract\u00e9risation multi-\u00e9chelle<\/a>, Antoine Aubel, PhD thesis (2023).<\/li>\n<\/ul>\n<\/div>\n<p>\n<\/div><\/div><\/div><\/div><\/div><\/section><section id=\"3d-printing-yield-stress-fluids\" class=\"kc-elm kc-css-538160 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-445089 kc_col-sm-12 kc_column kc_col-sm-12\"><div class=\"kc-col-container\">\n<div class=\"kc-elm kc-css-396228 divider_line\">\n\t<div class=\"divider_inner divider_line1\">\n\t\t\t<\/div>\n<\/div>\n<div class=\"kc-elm kc-css-442391 kc_text_block\"><\/p>\n<h3>3D Printing of Yield-Stress Fluids<\/h3>\n<p>\n<\/div><div class=\"kc-elm kc-css-362212 kc_text_block\"><\/p>\n<h5>P. Coussot, A. Geffrault (PhD)<\/h5>\n<h5>Collaboration : H. Bessaies-Bay, N. Roussel (CPDM)<\/h5>\n<p>\n<\/div><div class=\"kc-elm kc-css-602962 kc_text_block\"><\/p>\n<p>\nThree-dimensional printing of yield-stress fluids (which only flow <em>above<\/em> a critical applied shear stress) has unlocked new possibilities in the construction, food and healthcare sectors. Standard printing techniques consist in extruding then depositing a filament of yield-stress fluid atop the previous layer of fluid. One major difficulty is that instabilities may arise during deposition, with a catastrophic impact on the final three-dimensional structure.<\/p>\n<p>We have shown that these instabilities can be simply predicted as a function of the material properties and the printing parameters. To this end, we have studied the filament deposition of a model yield-stress fluid and examined the impact of the material yield stress, the distance between the extrusion head and the substrate, the extrusion speed, the head diameter and the printing speed. We have observed a broad range of patterns: drops, discontinuous lines, straight lines, meanders, alternated loops and single-sided loops. We have delineated the boundaries between these regimes and explained them using theoretical arguments, which led us to formulate stability regions based on the aforementioned system parameters.<\/p>\n<p>In a similar study, we have studied in detail the process leading to the formation of a fluidised region next to the &#8216;necking&#8217; between two yield-stress drops. Analysing our results, we have developed an original technique to measure the elongational rheological properties of yield-stress fluids and a simple technique to determine the yield stress of these materials from the mass of the detached drops.<\/p>\n<p>\n<\/div><div class=\"kc-elm kc-css-768490\" style=\"height: 20px; clear: both; width:100%;\"><\/div><div class=\"kc-elm kc-css-109834 kc_shortcode kc_single_image\">\n\n        <img decoding=\"async\" src=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/phase-diagram-anatole-3d-printing.jpg\" class=\"\" alt=\"\" \/>    <\/div>\n<div class=\"kc-elm kc-css-204480 kc_text_block\"><\/p>\n<p style=\"text-align: center;\"><em>Phase diagram of the various morphologies of a yield-stress filament printed from an extrusion head. We print a kaolin paste (yield stress\u00a0300 Pa) as a function of the extrusion speed V<sub>e<\/sub> and the vertical distance between the extrusion head and the substrate. The printing speed (translation of the extrusion head) is set to 1 cm\/s.<\/em><\/p>\n<p>\n<\/div>\n<div class=\"kc-elm kc-css-154388 divider_line\">\n\t<div class=\"divider_inner divider_line1\">\n\t\t\t<\/div>\n<\/div>\n<div class=\"kc-elm kc-css-843000 kc_text_block\"><\/p>\n<h4>References<\/h4>\n<ul>\n<li><a href=\"https:\/\/doi.org\/10.1016\/j.addma.2023.103752\">Printing by yield stress fluid shaping, A. Geffrault<\/a>, H. Bessaies-Bey, N. Roussel, P. Coussot, <em>Additive Manufacturing<\/em> <strong>75<\/strong>, 103725 (2023)<\/li>\n<li><a href=\"https:\/\/doi.org\/10.1122\/8.0000557\">Instant yield stress measurement from falling drop size: The \u201csyringe test\u201d<\/a>, A. Geffrault, H. Bessaies-Bey, N. Roussel, P. Coussot,\u00a0<em>Journal of Rheology<\/em> <strong>67<\/strong>, 305-314 (2023)<\/li>\n<\/ul>\n<p>\n<\/div><\/div><\/div><\/div><\/div><\/section><section id=\"numerical-methods-colloidal-suspensions\" class=\"kc-elm kc-css-679000 kc_row\"><div class=\"kc-row-container  kc-container\"><div class=\"kc-wrap-columns\"><div class=\"kc-elm kc-css-199762 kc_col-sm-12 kc_column kc_col-sm-12\"><div class=\"kc-col-container\">\n<div class=\"kc-elm kc-css-524821 divider_line\">\n\t<div class=\"divider_inner divider_line1\">\n\t\t\t<\/div>\n<\/div>\n<div class=\"kc-elm kc-css-926788 kc_text_block\"><\/p>\n<h3>Numerical Methods for Colloidal Suspensions<\/h3>\n<p>\n<\/div><div class=\"kc-elm kc-css-781835 kc_text_block\"><\/p>\n<h5>A. Lema\u00eetre, F. Puosi, D. Richard (Postdoc), P. Sanchez-Moreno Royer (PhD)<\/h5>\n<p>\n<\/div><div class=\"kc-elm kc-css-293960\" style=\"height: 10px; clear: both; width:100%;\"><\/div><div class=\"kc-elm kc-css-246381 kc_text_block\"><\/p>\n<p>\nMany materials from civil engineering and the environmental sector are dense colloidal pastes of varied shapes and sizes, from tens of nanometers to a few microns. Despite the enormous research efforts undertaken to master their formulation and their placement and shaping, we only have a very limited understanding of the physical mechanisms governing the inter-particle interactions. Discrete numerical simulations are indispensable to identify the relevant physical mechanisms in these systems and guide the interpretation of experiments.<\/p>\n<p>We have started developing numerical models (since <a href=\"https:\/\/navier-lab.fr\/en\/equipe\/puosi-francesco\/\">Francesco Puosi<\/a> joined us in December 2022) able to take into account the richness and the complexity of inter-particle interactions. We wish to understand the elementary physical mechanisms &#8212; at the particle scale &#8212; that determine the macroscopic behaviour of these systems. We are particularly interested in suspensions of adhesive spheres and an explicit model of clays taking into account the geometry (rod-like or platelet-like) of these particles to compute their exact interaction.<\/p>\n<p>\n<\/div><div class=\"kc-elm kc-css-734732\" style=\"height: 10px; clear: both; width:100%;\"><\/div><div class=\"kc-elm kc-css-11282 kc_shortcode kc_single_image\">\n\n        <img decoding=\"async\" src=\"https:\/\/navier-lab.fr\/wp-content\/uploads\/2024\/07\/colloidal-suspension-aging-1024x665.png\" class=\"\" alt=\"\" \/>    <\/div>\n<div class=\"kc-elm kc-css-146319 kc_text_block\"><\/p>\n<p style=\"text-align: center;\"><em>Numerical simulation of the aging of an adhesive colloidal suspension.<br \/>\n<\/em><\/p>\n<p>\n<\/div><div class=\"kc-elm kc-css-493175\" style=\"height: 20px; clear: both; width:100%;\"><\/div>\n<div class=\"kc-elm kc-css-735127 divider_line\">\n\t<div class=\"divider_inner divider_line1\">\n\t\t\t<\/div>\n<\/div>\n<div class=\"kc-elm kc-css-361402 kc_text_block\"><\/p>\n<h4>References<\/h4>\n<ul>\n<li><\/li>\n<\/ul>\n<p>\n<\/div><\/div><\/div><\/div><\/div><\/section><\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":162,"featured_media":0,"parent":12398,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-16459","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/pages\/16459","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/users\/162"}],"replies":[{"embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/comments?post=16459"}],"version-history":[{"count":24,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/pages\/16459\/revisions"}],"predecessor-version":[{"id":17257,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/pages\/16459\/revisions\/17257"}],"up":[{"embeddable":true,"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/pages\/12398"}],"wp:attachment":[{"href":"https:\/\/navier-lab.fr\/en\/wp-json\/wp\/v2\/media?parent=16459"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}