Ageing Effect on Ethyl Cellulose Films

✍ Scribed by Khare, P. K.; Jain, Sandeep K.; Paliwal, Sunil K.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 303 KB
• Volume: 42
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(199702)42:2<138::aid-pi654>3.0.co;2-4

✦ Synopsis

The e †ect of physical ageing on the electrical properties, such as thermally stimulated discharge currents (TSDC) and conduction currents, of ethyl cellulose (EC) has been analysed. The TSDC thermograms of EC samples, poled with 100 kV cm~1 at di †erent poling temperatures (i.e. 50, 70 and 90¡C) consist of two peaks located at 70 ^5¡C and 110 ^5¡C, respectively. The conductivity measurements were made over a time period of 101È103 min in the temperature range 30È125¡C with a poling Ðeld of 100 kV cm~1. It has been observed that physical ageing considerably a †ects the magnitude of the thermally stimulated depolarization and conduction currents of EC Ðlms. This ageing e †ect, which has been attributed to continuous vitriÐcation of a polymer, is considered to enhance the life-time of a polymer electret.