Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer
Abstract Developing green insulation materials has become an important direction for future research. As a new environmental insulation liquid, natural ester can effectively delay cellulose insulation polymer ageing. Mastering the mechanism of natural ester delaying the cellulose ageing could promot...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2022-10-01
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| Series: | High Voltage |
| Online Access: | https://doi.org/10.1049/hve2.12151 |
| _version_ | 1811337511956381696 |
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| author | Jian Hao Wenyu Ye Chenyu Gao Mengzhao Zhu Lijun Yang Ruijin Liao |
| author_facet | Jian Hao Wenyu Ye Chenyu Gao Mengzhao Zhu Lijun Yang Ruijin Liao |
| author_sort | Jian Hao |
| collection | DOAJ |
| description | Abstract Developing green insulation materials has become an important direction for future research. As a new environmental insulation liquid, natural ester can effectively delay cellulose insulation polymer ageing. Mastering the mechanism of natural ester delaying the cellulose ageing could promote its application in power transformers. In this study, based on the accelerated thermal ageing of pressboard immersed in natural ester and 25# mineral oil at 120°C for 221 days, the thermal ageing rate and the levelling off degree of polymerisation (LODP) for two kinds of oil‐impregnated pressboards were compared. The molecular level mechanism of natural ester delaying cellulose degradation and keeping higher LODP value was proposed using molecular dynamics simulation. At the early stage of thermal ageing, cellulose with a higher degree of polymerisation (DP) can form many hydrogen bonds with hydronium ions, and their binding energy is stronger, which can accelerate the acid hydrolysis of cellulose, causing the DP of pressboard immersed in natural ester and mineral oil to decrease rapidly. With the breaking of the cellulose molecular chain, the number of hydrogen bonds and binding energy between cellulose and hydronium ions becomes smaller and the thermal ageing rate decreases gradually. At the end stage of ageing, it is difficult for the hydronium ions to enter the crystalline cellulose, acid hydrolysis of crystalline cellulose is hard to conduct, leading to the occurrence of the LODP phenomenon. The degradation rate of cellulose in natural ester is only 50% of that in mineral oil. The cellulose LODP value in natural ester is over 200 larger than that in mineral oil. Compared with the mineral oil‐cellulose system, natural ester can form hydrogen bonds with hydronium ions and lead to fewer hydronium ions in cellulose, fewer hydrogen bonds and smaller binding energy between cellulose and hydronium ions, which can reduce the acid hydrolysis reaction of cellulose. This study provides a theoretical explanation for natural esters to delay the ageing of insulation paper. |
| first_indexed | 2024-04-13T17:56:03Z |
| format | Article |
| id | doaj.art-3a2f531cd99846fa8048ff1bd17d13a6 |
| institution | Directory Open Access Journal |
| issn | 2397-7264 |
| language | English |
| last_indexed | 2024-04-13T17:56:03Z |
| publishDate | 2022-10-01 |
| publisher | Wiley |
| record_format | Article |
| series | High Voltage |
| spelling | doaj.art-3a2f531cd99846fa8048ff1bd17d13a62022-12-22T02:36:31ZengWileyHigh Voltage2397-72642022-10-01751001101510.1049/hve2.12151Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymerJian Hao0Wenyu Ye1Chenyu Gao2Mengzhao Zhu3Lijun Yang4Ruijin Liao5State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing ChinaState Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing ChinaState Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing ChinaState Grid Shandong Electric Power Co. Shandong Electric Power Research Institute Jinan ChinaState Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing ChinaState Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing ChinaAbstract Developing green insulation materials has become an important direction for future research. As a new environmental insulation liquid, natural ester can effectively delay cellulose insulation polymer ageing. Mastering the mechanism of natural ester delaying the cellulose ageing could promote its application in power transformers. In this study, based on the accelerated thermal ageing of pressboard immersed in natural ester and 25# mineral oil at 120°C for 221 days, the thermal ageing rate and the levelling off degree of polymerisation (LODP) for two kinds of oil‐impregnated pressboards were compared. The molecular level mechanism of natural ester delaying cellulose degradation and keeping higher LODP value was proposed using molecular dynamics simulation. At the early stage of thermal ageing, cellulose with a higher degree of polymerisation (DP) can form many hydrogen bonds with hydronium ions, and their binding energy is stronger, which can accelerate the acid hydrolysis of cellulose, causing the DP of pressboard immersed in natural ester and mineral oil to decrease rapidly. With the breaking of the cellulose molecular chain, the number of hydrogen bonds and binding energy between cellulose and hydronium ions becomes smaller and the thermal ageing rate decreases gradually. At the end stage of ageing, it is difficult for the hydronium ions to enter the crystalline cellulose, acid hydrolysis of crystalline cellulose is hard to conduct, leading to the occurrence of the LODP phenomenon. The degradation rate of cellulose in natural ester is only 50% of that in mineral oil. The cellulose LODP value in natural ester is over 200 larger than that in mineral oil. Compared with the mineral oil‐cellulose system, natural ester can form hydrogen bonds with hydronium ions and lead to fewer hydronium ions in cellulose, fewer hydrogen bonds and smaller binding energy between cellulose and hydronium ions, which can reduce the acid hydrolysis reaction of cellulose. This study provides a theoretical explanation for natural esters to delay the ageing of insulation paper.https://doi.org/10.1049/hve2.12151 |
| spellingShingle | Jian Hao Wenyu Ye Chenyu Gao Mengzhao Zhu Lijun Yang Ruijin Liao Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer High Voltage |
| title | Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer |
| title_full | Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer |
| title_fullStr | Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer |
| title_full_unstemmed | Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer |
| title_short | Experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer |
| title_sort | experimental and molecular level analysis of natural ester delaying degradation of cellulose insulation polymer |
| url | https://doi.org/10.1049/hve2.12151 |
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