Effect of Accelerated Ageing on the Dielectric Behaviour of Some Varnish Dry Films  

作　　者：S.A.El-Henawii(Faculty of Science, Helwan University, Cairo, Egypt) 

出　　处：《Journal of Materials Science & Technology》1995年第5期323-328,共6页材料科学技术（英文版）

摘　　要：The variation of the dielectric constant e' and the dielectric loss e' of polyesteramide, alkyd polyesteramide and alkyd varnish dry films were measured within the frequency range from 105 to 107 Hz and the temperature range from 20 to 50℃. The varnish films were subjected to accelerated ageing by heating at 110℃ for diferent durations. The efect of the accelerated ageing on e' and e' were measured. The activation energy and the entropy change of dielectric relaxation for the dry films before and after ageing were also calculated. All the results obtained were recorded and discussed in correlation with the molecular structure of the investigated varnishes.The variation of the dielectric constant e' and the dielectric loss e' of polyesteramide, alkyd polyesteramide and alkyd varnish dry films were measured within the frequency range from 105 to 107 Hz and the temperature range from 20 to 50℃. The varnish films were subjected to accelerated ageing by heating at 110℃ for diferent durations. The efect of the accelerated ageing on e' and e' were measured. The activation energy and the entropy change of dielectric relaxation for the dry films before and after ageing were also calculated. All the results obtained were recorded and discussed in correlation with the molecular structure of the investigated varnishes.

关 键 词：Effect of Accelerated Ageing on the Dielectric Behaviour of Some Varnish Dry Films 

分 类 号：O631[理学—高分子化学]