M. Lança, C. Dias, D. D. Das Gupta, J. Marat-Mendes
{"title":"电老化与热老化低密度聚乙烯介电弛豫谱的比较研究","authors":"M. Lança, C. Dias, D. D. Das Gupta, J. Marat-Mendes","doi":"10.1109/CEIDP.2003.1254819","DOIUrl":null,"url":null,"abstract":"Low-density polyethylene (LDPE) films were thermally aged in a sodium chloride aqueous solution at constant temperature (thermal aging). Some of the samples were simultaneously immersed in solution and subjected to an electric AC field (electrical aging). The dielectric relaxation spectra at 30/spl deg/C in the range of 10/sup -5/ Hz to 10/sup 5/ Hz were obtained for unaged and aged samples. For the low frequency (LF) region (10/sup -5/ Hz to 10/sup -1/ Hz) the time domain technique was used. A lock-in amplifier was used for the 10/sup -1/ Hz to 10/sup 1/ Hz medium frequency (MF) region. While for the high frequency (HF), 10/sup -1/ Hz to 10/sup 5/ Hz, RLC bridge measurements were performed. The main differences can be seen between electrically, thermally aged and unaged LDPE in the HF and LF regions. The LF peak is a broad peak related to localized space charge injection driven by the electric field. For electrically aged samples this peak increases in an earlier stage of electrical aging, decreasing afterwards. While in thermally aged samples the peak amplitude always increases with aging time. Finally the HF shows the beginning of a peak due to the /spl gamma/ and /spl beta/ transitions. This peak decreases with aging disappearing for the most aged samples.","PeriodicalId":306575,"journal":{"name":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2003-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":"{\"title\":\"Comparative study of dielectric relaxation spectra of electrically and thermally aged low density polyethylene\",\"authors\":\"M. Lança, C. Dias, D. D. Das Gupta, J. Marat-Mendes\",\"doi\":\"10.1109/CEIDP.2003.1254819\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Low-density polyethylene (LDPE) films were thermally aged in a sodium chloride aqueous solution at constant temperature (thermal aging). Some of the samples were simultaneously immersed in solution and subjected to an electric AC field (electrical aging). The dielectric relaxation spectra at 30/spl deg/C in the range of 10/sup -5/ Hz to 10/sup 5/ Hz were obtained for unaged and aged samples. For the low frequency (LF) region (10/sup -5/ Hz to 10/sup -1/ Hz) the time domain technique was used. A lock-in amplifier was used for the 10/sup -1/ Hz to 10/sup 1/ Hz medium frequency (MF) region. While for the high frequency (HF), 10/sup -1/ Hz to 10/sup 5/ Hz, RLC bridge measurements were performed. The main differences can be seen between electrically, thermally aged and unaged LDPE in the HF and LF regions. The LF peak is a broad peak related to localized space charge injection driven by the electric field. For electrically aged samples this peak increases in an earlier stage of electrical aging, decreasing afterwards. While in thermally aged samples the peak amplitude always increases with aging time. Finally the HF shows the beginning of a peak due to the /spl gamma/ and /spl beta/ transitions. This peak decreases with aging disappearing for the most aged samples.\",\"PeriodicalId\":306575,\"journal\":{\"name\":\"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2003-10-19\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"2\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1109/CEIDP.2003.1254819\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/CEIDP.2003.1254819","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Comparative study of dielectric relaxation spectra of electrically and thermally aged low density polyethylene
Low-density polyethylene (LDPE) films were thermally aged in a sodium chloride aqueous solution at constant temperature (thermal aging). Some of the samples were simultaneously immersed in solution and subjected to an electric AC field (electrical aging). The dielectric relaxation spectra at 30/spl deg/C in the range of 10/sup -5/ Hz to 10/sup 5/ Hz were obtained for unaged and aged samples. For the low frequency (LF) region (10/sup -5/ Hz to 10/sup -1/ Hz) the time domain technique was used. A lock-in amplifier was used for the 10/sup -1/ Hz to 10/sup 1/ Hz medium frequency (MF) region. While for the high frequency (HF), 10/sup -1/ Hz to 10/sup 5/ Hz, RLC bridge measurements were performed. The main differences can be seen between electrically, thermally aged and unaged LDPE in the HF and LF regions. The LF peak is a broad peak related to localized space charge injection driven by the electric field. For electrically aged samples this peak increases in an earlier stage of electrical aging, decreasing afterwards. While in thermally aged samples the peak amplitude always increases with aging time. Finally the HF shows the beginning of a peak due to the /spl gamma/ and /spl beta/ transitions. This peak decreases with aging disappearing for the most aged samples.