{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/20605"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/20605","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Flow properties of a colloidal gel","abstract":"ETDs are only available to UIUC Users without author permission","abstract_html":"ETDs are only available to UIUC Users without author permission","abstract_has_math":false,"creators":["Rueb, Christopher John"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemical Engineering","degree_department":null,"school":null,"contributors":["Zukoski, Charles F."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:44:02Z","date_published":"2011-05-07T12:44:02Z","updated_at":"2026-07-22T22:25:16Z","subjects":["Chemistry, Physical","Engineering, Chemical"],"languages":["eng"],"rights":["Copyright 1994 Rueb, Christopher John"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9503305","(UMI)AAI9503305"],"render_values":[{"text":"AAI9503305","href":null,"code":true},{"text":"(UMI)AAI9503305","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/20605","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Zukoski, Charles F."]},{"key":"dc:creator","label":"Author","values":["Rueb, Christopher John"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:44:02Z","10000-01-01","1994"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemical Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Chemistry, Physical","Engineering, Chemical"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1994 Rueb, Christopher John"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9503305","(UMI)AAI9503305","http://hdl.handle.net/2142/20605"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["ETDs are only available to UIUC Users without author permission","U of I Only","The flow properties of a colloidal suspension are influenced by attractive interactions. In this work we study the mechanical behavior of a weakly flocculated colloidal gel. A model system consisting of silica spheres ($\\sigma\\approx100$ nm) coated with steryl alcohol chains and suspended in decalin or tetradecane was used. At elevated temperatures these suspensions behave effectively as hard spheres. Lowering the temperature below a well defined gelation temperature, T$\\sb{\\rm G}$, causes this system to form a space filling gel. The strength of interparticle attractions ($\\epsilon$) are controlled by temperature. At T$\\sb{\\rm G}$ mechanical behavior suggests a percolation transition. The gel microstructure was probed using neutron scattering. The application of high shear causes the gel microstructure to densify. We have characterized the gel relaxation time, G$\\sp\\prime$, and limit of linearity, $\\gamma\\sb{\\rm M}$, as a function of $\\phi$ (constant $\\varepsilon$) and as a function of $\\varepsilon$ (constant $\\phi$). Increasing $\\varepsilon$ causes the gel relaxation time to decrease, G$\\sp\\prime$ to increase and $\\gamma\\sb{\\rm M}$ to decrease. The scaling variable $\\phi/\\phi\\sb{\\rm G}$, suggested in percolation theory to describe mechanical behavior near the percolation transition, acts to collapse G$\\sp\\prime$ and $\\gamma\\sb{\\rm M}$ data suggesting that along lines of constant $\\phi/\\phi\\sb{\\rm G}$ these gels are rheologically identical.","These gels show a time induced yielding phenomena where upon application of a constant stress the gel first responds as if a solid-like material. The gel creeps slowly with time and after an induction time begins to flow at a steady state rate of deformation. Wall slip was ruled out and instead we suggest that this behavior is related to a relaxation mechanism in the gel.","Made available in DSpace on 2011-05-07T12:44:02Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9503305.pdf: 8573803 bytes, checksum: 67afbb6e554912a247c63b3d1dd1f047 (MD5) Previous issue date: 1994","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:45:01Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:19:53-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission"]},{"key":"dc:title","label":"Title","values":["Flow properties of a colloidal gel"]}]}],"canonical_facts":{"dc:contributor":["Zukoski, Charles F."],"dc:creator":["Rueb, Christopher John"],"dc:date":["2011-05-07T12:44:02Z","10000-01-01","1994"],"dc:description":["ETDs are only available to UIUC Users without author permission","U of I Only","The flow properties of a colloidal suspension are influenced by attractive interactions. In this work we study the mechanical behavior of a weakly flocculated colloidal gel. A model system consisting of silica spheres ($\\sigma\\approx100$ nm) coated with steryl alcohol chains and suspended in decalin or tetradecane was used. At elevated temperatures these suspensions behave effectively as hard spheres. Lowering the temperature below a well defined gelation temperature, T$\\sb{\\rm G}$, causes this system to form a space filling gel. The strength of interparticle attractions ($\\epsilon$) are controlled by temperature. At T$\\sb{\\rm G}$ mechanical behavior suggests a percolation transition. The gel microstructure was probed using neutron scattering. The application of high shear causes the gel microstructure to densify. We have characterized the gel relaxation time, G$\\sp\\prime$, and limit of linearity, $\\gamma\\sb{\\rm M}$, as a function of $\\phi$ (constant $\\varepsilon$) and as a function of $\\varepsilon$ (constant $\\phi$). Increasing $\\varepsilon$ causes the gel relaxation time to decrease, G$\\sp\\prime$ to increase and $\\gamma\\sb{\\rm M}$ to decrease. The scaling variable $\\phi/\\phi\\sb{\\rm G}$, suggested in percolation theory to describe mechanical behavior near the percolation transition, acts to collapse G$\\sp\\prime$ and $\\gamma\\sb{\\rm M}$ data suggesting that along lines of constant $\\phi/\\phi\\sb{\\rm G}$ these gels are rheologically identical.","These gels show a time induced yielding phenomena where upon application of a constant stress the gel first responds as if a solid-like material. The gel creeps slowly with time and after an induction time begins to flow at a steady state rate of deformation. Wall slip was ruled out and instead we suggest that this behavior is related to a relaxation mechanism in the gel.","Made available in DSpace on 2011-05-07T12:44:02Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9503305.pdf: 8573803 bytes, checksum: 67afbb6e554912a247c63b3d1dd1f047 (MD5) Previous issue date: 1994","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:45:01Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:19:53-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission"],"dc:identifier":["AAI9503305","(UMI)AAI9503305","http://hdl.handle.net/2142/20605"],"dc:language":["eng"],"dc:rights":["Copyright 1994 Rueb, Christopher John"],"dc:subject":["Chemistry, Physical","Engineering, Chemical"],"dc:title":["Flow properties of a colloidal gel"],"dc:type":["text"],"thesis:degree_discipline":["Chemical Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:16Z"}