{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/71014"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/71014","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Molecular weight and concentration dependence of the thermal conductivity of polystyrene in benzene","abstract":"The thermal conductivities of polystyrene in benzene solutions at concentrations of 0.l to 15 weight percent were measured at 25° C and atmospheric pressure. Osmotic pressure measurements and information supplied by the manufacturer indicated number average molecular weights (M̅<sub>N</sub>) of 21,000, 264,000, and 660,000 for the three polystyrene polymers studied. The following equation was obtained by regression analysis of the results and predicts the measured thermal conductivity within ± 2 percent in the range of variables studied. K = 0.1088 - 0.1311 C + 0.57629 C² - 6.40 x 10⁻⁵ (M̅<sub>N</sub> x 10⁻⁵)² - 4.2 x 10⁻³ C(M̅<sub>N</sub> x 10⁻⁵) where: K = thermal conductivity of solution, Btu/hr-ft-°F C = weight fraction polymer M̅<sub>N</sub> = number average molecular weight The conductivities were measured in a steady-state concentric cylinder apparatus developed for measuring the thermal conductivity of viscous liquids. The annular gap was 0.052 inches and guard heaters were employed to minimize end losses and distortion of the steady-state temperature distribution at the ends. The apparatus was calibrated with three liquids of known thermal conductivity, water, cyclohexanol and ethylene glycol. The calibration factor was found to be constant to within experimental error (± 3 percent) over the range of measurements.","abstract_html":"The thermal conductivities of polystyrene in benzene solutions at concentrations of 0.l to 15 weight percent were measured at 25° C and atmospheric pressure. Osmotic pressure measurements and information supplied by the manufacturer indicated number average molecular weights (M̅&lt;sub&gt;N&lt;/sub&gt;) of 21,000, 264,000, and 660,000 for the three polystyrene polymers studied. The following equation was obtained by regression analysis of the results and predicts the measured thermal conductivity within ± 2 percent in the range of variables studied. K = 0.1088 - 0.1311 C + 0.57629 C² - 6.40 x 10⁻⁵ (M̅&lt;sub&gt;N&lt;/sub&gt; x 10⁻⁵)² - 4.2 x 10⁻³ C(M̅&lt;sub&gt;N&lt;/sub&gt; x 10⁻⁵) where: K = thermal conductivity of solution, Btu/hr-ft-°F C = weight fraction polymer M̅&lt;sub&gt;N&lt;/sub&gt; = number average molecular weight The conductivities were measured in a steady-state concentric cylinder apparatus developed for measuring the thermal conductivity of viscous liquids. The annular gap was 0.052 inches and guard heaters were employed to minimize end losses and distortion of the steady-state temperature distribution at the ends. The apparatus was calibrated with three liquids of known thermal conductivity, water, cyclohexanol and ethylene glycol. The calibration factor was found to be constant to within experimental error (± 3 percent) over the range of measurements.","abstract_has_math":false,"creators":["Epps, Lionel Bailey"],"institution":"Virginia Polytechnic Institute","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Chemical Engineering","degree_department":"Chemical Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1968,"date_issued":"1968","date_published":"1968","updated_at":"2026-07-22T22:20:23Z","subjects":[],"languages":["en_US"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10919/71014","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Chemical Engineering"]},{"key":"dc:creator","label":"Author","values":["Epps, Lionel Bailey"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2016-05-23T14:57:09Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2016-05-23T14:57:09Z"]},{"key":"dc:date.issued","label":"Date","values":["1968"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Polytechnic Institute"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemical Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/71014"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The thermal conductivities of polystyrene in benzene solutions at concentrations of 0.l to 15 weight percent were measured at 25° C and atmospheric pressure. Osmotic pressure measurements and information supplied by the manufacturer indicated number average molecular weights (M̅<sub>N</sub>) of 21,000, 264,000, and 660,000 for the three polystyrene polymers studied. The following equation was obtained by regression analysis of the results and predicts the measured thermal conductivity within ± 2 percent in the range of variables studied. K = 0.1088 - 0.1311 C + 0.57629 C² - 6.40 x 10⁻⁵ (M̅<sub>N</sub> x 10⁻⁵)² - 4.2 x 10⁻³ C(M̅<sub>N</sub> x 10⁻⁵) where: K = thermal conductivity of solution, Btu/hr-ft-°F C = weight fraction polymer M̅<sub>N</sub> = number average molecular weight The conductivities were measured in a steady-state concentric cylinder apparatus developed for measuring the thermal conductivity of viscous liquids. The annular gap was 0.052 inches and guard heaters were employed to minimize end losses and distortion of the steady-state temperature distribution at the ends. The apparatus was calibrated with three liquids of known thermal conductivity, water, cyclohexanol and ethylene glycol. The calibration factor was found to be constant to within experimental error (± 3 percent) over the range of measurements."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Molecular weight and concentration dependence of the thermal conductivity of polystyrene in benzene"]}]}],"canonical_facts":{"dc:contributor.department":["Chemical Engineering"],"dc:creator":["Epps, Lionel Bailey"],"dc:date.accessioned":["2016-05-23T14:57:09Z"],"dc:date.available":["2016-05-23T14:57:09Z"],"dc:date.issued":["1968"],"dc:description.abstract":["The thermal conductivities of polystyrene in benzene solutions at concentrations of 0.l to 15 weight percent were measured at 25° C and atmospheric pressure. Osmotic pressure measurements and information supplied by the manufacturer indicated number average molecular weights (M̅<sub>N</sub>) of 21,000, 264,000, and 660,000 for the three polystyrene polymers studied. The following equation was obtained by regression analysis of the results and predicts the measured thermal conductivity within ± 2 percent in the range of variables studied. K = 0.1088 - 0.1311 C + 0.57629 C² - 6.40 x 10⁻⁵ (M̅<sub>N</sub> x 10⁻⁵)² - 4.2 x 10⁻³ C(M̅<sub>N</sub> x 10⁻⁵) where: K = thermal conductivity of solution, Btu/hr-ft-°F C = weight fraction polymer M̅<sub>N</sub> = number average molecular weight The conductivities were measured in a steady-state concentric cylinder apparatus developed for measuring the thermal conductivity of viscous liquids. The annular gap was 0.052 inches and guard heaters were employed to minimize end losses and distortion of the steady-state temperature distribution at the ends. The apparatus was calibrated with three liquids of known thermal conductivity, water, cyclohexanol and ethylene glycol. The calibration factor was found to be constant to within experimental error (± 3 percent) over the range of measurements."],"dc:description.degree":["Master of Science"],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/71014"],"dc:language.iso":["en_US"],"dc:publisher":["Virginia Polytechnic Institute"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Molecular weight and concentration dependence of the thermal conductivity of polystyrene in benzene"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Chemical Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute"]},"updated_at":"2026-07-22T22:20:23Z"}