Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites
Our research focuses on the processing of a thermoplastic magnetorheological elastomer (MRE) by solvent-casting a thermoplastic polyurethane (PU) elastomer with magnetic particulate for fused filament fabrication (FFF) applications. MREs are typically prepared by curing a thermoset silicone with mag...
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AIMS Press
2019-05-01
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author | Thomas J. Lee Andrew H. Morgenstern Thomas A. Höft Brittany B. Nelson-Cheeseman |
author_facet | Thomas J. Lee Andrew H. Morgenstern Thomas A. Höft Brittany B. Nelson-Cheeseman |
author_sort | Thomas J. Lee |
collection | DOAJ |
description | Our research focuses on the processing of a thermoplastic magnetorheological elastomer (MRE) by solvent-casting a thermoplastic polyurethane (PU) elastomer with magnetic particulate for fused filament fabrication (FFF) applications. MREs are typically prepared by curing a thermoset silicone with magnetic particulate. Alternatively, thermoplastic MREs may be produced by the addition of magnetic particulate to a thermoplastic elastomer (TPE). FFF is a valuable manufacturing technique that allows for the creation of parts with inherent anisotropies. For the case of an MRE, FFF allows for the production of structures with tunable magnetic susceptibility along different axes. In these composites, the degree of particulate dispersion significantly affects the isotropy of material properties, which becomes increasingly important when small material volumes are used, such as in FFF. Incorporating solvent-casting as a method of producing polymer composites allows for greater control over the particulate addition method, leading to improved dispersion when compared to a polymer melt. For our purposes, composite films were produced in order to examine the effect of wet vs. dry addition of particulate on dispersion. The solvent used for casting was dimethylformamide (DMF). Preparation of polymer solutions included dissolution of PU in DMF to 20 w/v% followed by addition of the magnetic particulate. The particulates used were <150 µm iron powder and 2–4 µm magnetite powder. Composite solutions were made to concentrations of 20, 30, and 40 w/w% particulate to polymer by addition of either dry particulate or particulate pre-suspended in DMF. It was found that wet addition of particulate led to improvement in particulate agglomeration and magnetite particulate exhibited a significantly higher degree of agglomeration than iron. |
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spelling | doaj.art-6b323f8bad90405c824913f5e2cc91bc2022-12-22T01:12:22ZengAIMS PressAIMS Materials Science2372-04682372-04842019-05-016335436210.3934/matersci.2019.3.354Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer compositesThomas J. Lee0Andrew H. Morgenstern1Thomas A. Höft2Brittany B. Nelson-Cheeseman31 Department of Mechanical Engineering, University of St. Thomas, St. Paul, MN 55105, USA1 Department of Mechanical Engineering, University of St. Thomas, St. Paul, MN 55105, USA2 Department of Mathematics, University of St. Thomas, St. Paul, MN 55105, USA1 Department of Mechanical Engineering, University of St. Thomas, St. Paul, MN 55105, USAOur research focuses on the processing of a thermoplastic magnetorheological elastomer (MRE) by solvent-casting a thermoplastic polyurethane (PU) elastomer with magnetic particulate for fused filament fabrication (FFF) applications. MREs are typically prepared by curing a thermoset silicone with magnetic particulate. Alternatively, thermoplastic MREs may be produced by the addition of magnetic particulate to a thermoplastic elastomer (TPE). FFF is a valuable manufacturing technique that allows for the creation of parts with inherent anisotropies. For the case of an MRE, FFF allows for the production of structures with tunable magnetic susceptibility along different axes. In these composites, the degree of particulate dispersion significantly affects the isotropy of material properties, which becomes increasingly important when small material volumes are used, such as in FFF. Incorporating solvent-casting as a method of producing polymer composites allows for greater control over the particulate addition method, leading to improved dispersion when compared to a polymer melt. For our purposes, composite films were produced in order to examine the effect of wet vs. dry addition of particulate on dispersion. The solvent used for casting was dimethylformamide (DMF). Preparation of polymer solutions included dissolution of PU in DMF to 20 w/v% followed by addition of the magnetic particulate. The particulates used were <150 µm iron powder and 2–4 µm magnetite powder. Composite solutions were made to concentrations of 20, 30, and 40 w/w% particulate to polymer by addition of either dry particulate or particulate pre-suspended in DMF. It was found that wet addition of particulate led to improvement in particulate agglomeration and magnetite particulate exhibited a significantly higher degree of agglomeration than iron.https://www.aimspress.com/article/10.3934/matersci.2019.3.354/fulltext.htmlthermoplastic elastomermagnetorheological elastomermagnetic elastomersolvent castingparticulate dispersion |
spellingShingle | Thomas J. Lee Andrew H. Morgenstern Thomas A. Höft Brittany B. Nelson-Cheeseman Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites AIMS Materials Science thermoplastic elastomer magnetorheological elastomer magnetic elastomer solvent casting particulate dispersion |
title | Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites |
title_full | Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites |
title_fullStr | Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites |
title_full_unstemmed | Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites |
title_short | Dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites |
title_sort | dispersion of particulate in solvent cast magnetic thermoplastic polyurethane elastomer composites |
topic | thermoplastic elastomer magnetorheological elastomer magnetic elastomer solvent casting particulate dispersion |
url | https://www.aimspress.com/article/10.3934/matersci.2019.3.354/fulltext.html |
work_keys_str_mv | AT thomasjlee dispersionofparticulateinsolventcastmagneticthermoplasticpolyurethaneelastomercomposites AT andrewhmorgenstern dispersionofparticulateinsolventcastmagneticthermoplasticpolyurethaneelastomercomposites AT thomasahoft dispersionofparticulateinsolventcastmagneticthermoplasticpolyurethaneelastomercomposites AT brittanybnelsoncheeseman dispersionofparticulateinsolventcastmagneticthermoplasticpolyurethaneelastomercomposites |