Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric Field
In this work, we study the effect of strong electric fields on a polymer/graphene composite and the resulting morphology upon its dielectric breakdown. Our model system was produced by compounding up to 0.25 wt % graphene nanoplatelets (GNP) into poly(ethylene-<i>co</i>-vinyl acetate) (E...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-05-01
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| Series: | Journal of Composites Science |
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| Online Access: | https://www.mdpi.com/2504-477X/6/5/139 |
| _version_ | 1797498802655985664 |
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| author | Yangming Kou Xiang Cheng Christopher W. Macosko |
| author_facet | Yangming Kou Xiang Cheng Christopher W. Macosko |
| author_sort | Yangming Kou |
| collection | DOAJ |
| description | In this work, we study the effect of strong electric fields on a polymer/graphene composite and the resulting morphology upon its dielectric breakdown. Our model system was produced by compounding up to 0.25 wt % graphene nanoplatelets (GNP) into poly(ethylene-<i>co</i>-vinyl acetate) (EVA), which is a soft polymer with low melt viscosity. A strong electric field of up to 400 V<sub>rms</sub>/mm was applied to the EVA/GNP composite in the melt. The sample’s resistance over the electric field application was simultaneously measured. Despite the low GNP loading, which was below the theoretical percolation threshold, the electric conductivity of the composite during electric field application dramatically increased to >10<sup>−6</sup> S/cm over 5 min of electric field application before reaching the current limit of the experimental apparatus. Conductivity growth follows the same scaling relationship of the theoretical model that predicts the rotation and translation time of GNPs in a polymer melt as a function of electric field strength. Since no significant GNP alignment in the composite was observed under transmission electron microscopy (TEM), we hypothesized that the increase in electrical conductivity was due to local electrical treeing of the polymer matrix, which eventually leads to dielectric breakdown of the composite. Electrical treeing is likely initiated by local GNP agglomerates and propagated through conductive channels formed during progressive dielectric breakdown. |
| first_indexed | 2024-03-10T03:38:36Z |
| format | Article |
| id | doaj.art-5d58f07af4c04f9889983ee9e6bc2aef |
| institution | Directory Open Access Journal |
| issn | 2504-477X |
| language | English |
| last_indexed | 2024-03-10T03:38:36Z |
| publishDate | 2022-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Composites Science |
| spelling | doaj.art-5d58f07af4c04f9889983ee9e6bc2aef2023-11-23T11:37:41ZengMDPI AGJournal of Composites Science2504-477X2022-05-016513910.3390/jcs6050139Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric FieldYangming Kou0Xiang Cheng1Christopher W. Macosko2Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, MN 55455, USA Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, MN 55455, USA Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, MN 55455, USA In this work, we study the effect of strong electric fields on a polymer/graphene composite and the resulting morphology upon its dielectric breakdown. Our model system was produced by compounding up to 0.25 wt % graphene nanoplatelets (GNP) into poly(ethylene-<i>co</i>-vinyl acetate) (EVA), which is a soft polymer with low melt viscosity. A strong electric field of up to 400 V<sub>rms</sub>/mm was applied to the EVA/GNP composite in the melt. The sample’s resistance over the electric field application was simultaneously measured. Despite the low GNP loading, which was below the theoretical percolation threshold, the electric conductivity of the composite during electric field application dramatically increased to >10<sup>−6</sup> S/cm over 5 min of electric field application before reaching the current limit of the experimental apparatus. Conductivity growth follows the same scaling relationship of the theoretical model that predicts the rotation and translation time of GNPs in a polymer melt as a function of electric field strength. Since no significant GNP alignment in the composite was observed under transmission electron microscopy (TEM), we hypothesized that the increase in electrical conductivity was due to local electrical treeing of the polymer matrix, which eventually leads to dielectric breakdown of the composite. Electrical treeing is likely initiated by local GNP agglomerates and propagated through conductive channels formed during progressive dielectric breakdown.https://www.mdpi.com/2504-477X/6/5/139grapheneelectric fieldpolymer compositedegradation |
| spellingShingle | Yangming Kou Xiang Cheng Christopher W. Macosko Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric Field Journal of Composites Science graphene electric field polymer composite degradation |
| title | Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric Field |
| title_full | Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric Field |
| title_fullStr | Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric Field |
| title_full_unstemmed | Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric Field |
| title_short | Degradation and Breakdown of Polymer/Graphene Composites under Strong Electric Field |
| title_sort | degradation and breakdown of polymer graphene composites under strong electric field |
| topic | graphene electric field polymer composite degradation |
| url | https://www.mdpi.com/2504-477X/6/5/139 |
| work_keys_str_mv | AT yangmingkou degradationandbreakdownofpolymergraphenecompositesunderstrongelectricfield AT xiangcheng degradationandbreakdownofpolymergraphenecompositesunderstrongelectricfield AT christopherwmacosko degradationandbreakdownofpolymergraphenecompositesunderstrongelectricfield |