Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites
Incorporating nanofillers into elastomers leads to composites with an enormous potential regarding their properties. Unfortunately, nanofillers tend to form agglomerates inhibiting adequate filler dispersion. Therefore, different carbon nanotube (CNT) pretreatment methods were analyzed in this study...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-04-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/13/9/1355 |
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| author | Astrid Diekmann Marvin C. V. Omelan Ulrich Giese |
| author_facet | Astrid Diekmann Marvin C. V. Omelan Ulrich Giese |
| author_sort | Astrid Diekmann |
| collection | DOAJ |
| description | Incorporating nanofillers into elastomers leads to composites with an enormous potential regarding their properties. Unfortunately, nanofillers tend to form agglomerates inhibiting adequate filler dispersion. Therefore, different carbon nanotube (CNT) pretreatment methods were analyzed in this study to enhance the filler dispersion in polydimethylsiloxane (PDMS)/CNT-composites. By pre-dispersing CNTs in solvents an increase in electrical conductivity could be observed within the sequence of tetrahydrofuran (THF) > acetone > chloroform. Optimization of the pre-dispersion step results in an AC conductivity of 3.2 × 10<sup>−4</sup> S/cm at 1 Hz and 0.5 wt.% of CNTs and the electrical percolation threshold is decreased to 0.1 wt.% of CNTs. Optimum parameters imply the use of an ultrasonic finger for 60 min in THF. However, solvent residues cause a softening effect deteriorating the mechanical performance of these composites. Concerning the pretreatment of CNTs by physical functionalization, the use of surfactants (sodium dodecylbenzenesulfonate (SDBS) and polyoxyethylene lauryl ether (“Brij35”)) leads to no improvement, neither in electrical conductivity nor in mechanical properties. Chemical functionalization enhances the compatibility of PDMS and CNT but damages the carbon nanotubes due to the oxidation process so that the improvement in conductivity and reinforcement is superimposed by the CNT damage even for mild oxidation conditions. |
| first_indexed | 2024-03-10T12:06:56Z |
| format | Article |
| id | doaj.art-a90b005e61374a09a21bdcf39f4136fb |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-03-10T12:06:56Z |
| publishDate | 2021-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-a90b005e61374a09a21bdcf39f4136fb2023-11-21T16:30:45ZengMDPI AGPolymers2073-43602021-04-01139135510.3390/polym13091355Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-NanocompositesAstrid Diekmann0Marvin C. V. Omelan1Ulrich Giese2Deutsches Institut für Kautschuktechnologie e. V., Eupener Straße 33, 30519 Hannover, GermanyDeutsches Institut für Kautschuktechnologie e. V., Eupener Straße 33, 30519 Hannover, GermanyDeutsches Institut für Kautschuktechnologie e. V., Eupener Straße 33, 30519 Hannover, GermanyIncorporating nanofillers into elastomers leads to composites with an enormous potential regarding their properties. Unfortunately, nanofillers tend to form agglomerates inhibiting adequate filler dispersion. Therefore, different carbon nanotube (CNT) pretreatment methods were analyzed in this study to enhance the filler dispersion in polydimethylsiloxane (PDMS)/CNT-composites. By pre-dispersing CNTs in solvents an increase in electrical conductivity could be observed within the sequence of tetrahydrofuran (THF) > acetone > chloroform. Optimization of the pre-dispersion step results in an AC conductivity of 3.2 × 10<sup>−4</sup> S/cm at 1 Hz and 0.5 wt.% of CNTs and the electrical percolation threshold is decreased to 0.1 wt.% of CNTs. Optimum parameters imply the use of an ultrasonic finger for 60 min in THF. However, solvent residues cause a softening effect deteriorating the mechanical performance of these composites. Concerning the pretreatment of CNTs by physical functionalization, the use of surfactants (sodium dodecylbenzenesulfonate (SDBS) and polyoxyethylene lauryl ether (“Brij35”)) leads to no improvement, neither in electrical conductivity nor in mechanical properties. Chemical functionalization enhances the compatibility of PDMS and CNT but damages the carbon nanotubes due to the oxidation process so that the improvement in conductivity and reinforcement is superimposed by the CNT damage even for mild oxidation conditions.https://www.mdpi.com/2073-4360/13/9/1355dispersionfiller–filler interactionsfunctionalizationpolydimethylsiloxanecarbon nanotubes |
| spellingShingle | Astrid Diekmann Marvin C. V. Omelan Ulrich Giese Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites Polymers dispersion filler–filler interactions functionalization polydimethylsiloxane carbon nanotubes |
| title | Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites |
| title_full | Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites |
| title_fullStr | Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites |
| title_full_unstemmed | Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites |
| title_short | Influence of Carbon Nanotube-Pretreatment on the Properties of Polydimethylsiloxane/Carbon Nanotube-Nanocomposites |
| title_sort | influence of carbon nanotube pretreatment on the properties of polydimethylsiloxane carbon nanotube nanocomposites |
| topic | dispersion filler–filler interactions functionalization polydimethylsiloxane carbon nanotubes |
| url | https://www.mdpi.com/2073-4360/13/9/1355 |
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