Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone Composites
The effect of ionic surfactants and manufacturing methods on the separation and distribution of multi-wall carbon nanotubes (CNTs) in a silicone matrix are investigated. The CNTs are dispersed in an aqueous solution of the anionic surfactant dodecylbenzene sulfonic acid (DBSA), the cationic surfacta...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2012-11-01
|
| Series: | Molecules |
| Subjects: | |
| Online Access: | http://www.mdpi.com/1420-3049/17/11/13157 |
| _version_ | 1819264162305409024 |
|---|---|
| author | Martina Hřibová Matej Mičušík Natalia Kazantseva Markéta Ilčíková Petr Svoboda Robert Moučka Jarmila Vilčáková Mária Omastová |
| author_facet | Martina Hřibová Matej Mičušík Natalia Kazantseva Markéta Ilčíková Petr Svoboda Robert Moučka Jarmila Vilčáková Mária Omastová |
| author_sort | Martina Hřibová |
| collection | DOAJ |
| description | The effect of ionic surfactants and manufacturing methods on the separation and distribution of multi-wall carbon nanotubes (CNTs) in a silicone matrix are investigated. The CNTs are dispersed in an aqueous solution of the anionic surfactant dodecylbenzene sulfonic acid (DBSA), the cationic surfactant cetyltrimethylammonium bromide (CTAB), and in a DBSA/CTAB surfactant mixture. Four types of CNT-based composites of various concentrations from 0 to 6 vol.% are prepared by simple mechanical mixing and sonication. The morphology, electrical and thermal conductivity of the CNT-based composites are analyzed. The incorporation of both neat and modified CNTs leads to an increase in electrical and thermal conductivity. The dependence of DC conductivity versus CNT concentration shows percolation behaviour with a percolation threshold of about 2 vol.% in composites with neat CNT. The modification of CNTs by DBSA increases the percolation threshold to 4 vol.% due to the isolation/separation of individual CNTs. This, in turn, results in a significant decrease in the complex permittivity of CNT–DBSA-based composites. In contrast to the percolation behaviour of DC conductivity, the concentration dependence of thermal conductivity exhibits a linear dependence, the thermal conductivity of composites with modified CNTs being lower than that of composites with neat CNTs. All these results provide evidence that the modification of CNTs by DBSA followed by sonication allows one to produce composites with high homogeneity. |
| first_indexed | 2024-12-23T20:25:06Z |
| format | Article |
| id | doaj.art-0cc294b3b9c34facb5719be0cb43adb5 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-12-23T20:25:06Z |
| publishDate | 2012-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-0cc294b3b9c34facb5719be0cb43adb52022-12-21T17:32:24ZengMDPI AGMolecules1420-30492012-11-011711131571317410.3390/molecules171113157Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone CompositesMartina HřibováMatej MičušíkNatalia KazantsevaMarkéta IlčíkováPetr SvobodaRobert MoučkaJarmila VilčákováMária OmastováThe effect of ionic surfactants and manufacturing methods on the separation and distribution of multi-wall carbon nanotubes (CNTs) in a silicone matrix are investigated. The CNTs are dispersed in an aqueous solution of the anionic surfactant dodecylbenzene sulfonic acid (DBSA), the cationic surfactant cetyltrimethylammonium bromide (CTAB), and in a DBSA/CTAB surfactant mixture. Four types of CNT-based composites of various concentrations from 0 to 6 vol.% are prepared by simple mechanical mixing and sonication. The morphology, electrical and thermal conductivity of the CNT-based composites are analyzed. The incorporation of both neat and modified CNTs leads to an increase in electrical and thermal conductivity. The dependence of DC conductivity versus CNT concentration shows percolation behaviour with a percolation threshold of about 2 vol.% in composites with neat CNT. The modification of CNTs by DBSA increases the percolation threshold to 4 vol.% due to the isolation/separation of individual CNTs. This, in turn, results in a significant decrease in the complex permittivity of CNT–DBSA-based composites. In contrast to the percolation behaviour of DC conductivity, the concentration dependence of thermal conductivity exhibits a linear dependence, the thermal conductivity of composites with modified CNTs being lower than that of composites with neat CNTs. All these results provide evidence that the modification of CNTs by DBSA followed by sonication allows one to produce composites with high homogeneity.http://www.mdpi.com/1420-3049/17/11/13157multi-wall carbon nanotubesmodification of carbon nanotubes by ionic surfactantssilicone based compositeselectrical conductivitythermal conductivitypercolation thresholdcomplex permittivity |
| spellingShingle | Martina Hřibová Matej Mičušík Natalia Kazantseva Markéta Ilčíková Petr Svoboda Robert Moučka Jarmila Vilčáková Mária Omastová Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone Composites Molecules multi-wall carbon nanotubes modification of carbon nanotubes by ionic surfactants silicone based composites electrical conductivity thermal conductivity percolation threshold complex permittivity |
| title | Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone Composites |
| title_full | Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone Composites |
| title_fullStr | Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone Composites |
| title_full_unstemmed | Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone Composites |
| title_short | Effect of Surfactants and Manufacturing Methods on the Electrical and Thermal Conductivity of Carbon Nanotube/Silicone Composites |
| title_sort | effect of surfactants and manufacturing methods on the electrical and thermal conductivity of carbon nanotube silicone composites |
| topic | multi-wall carbon nanotubes modification of carbon nanotubes by ionic surfactants silicone based composites electrical conductivity thermal conductivity percolation threshold complex permittivity |
| url | http://www.mdpi.com/1420-3049/17/11/13157 |
| work_keys_str_mv | AT martinahribova effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites AT matejmicusik effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites AT nataliakazantseva effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites AT marketailcikova effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites AT petrsvoboda effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites AT robertmoucka effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites AT jarmilavilcakova effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites AT mariaomastova effectofsurfactantsandmanufacturingmethodsontheelectricalandthermalconductivityofcarbonnanotubesiliconecomposites |