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Aging phenomena in polystyrene thin films

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 نشر من قبل Koji Fukao
 تاريخ النشر 2008
  مجال البحث فيزياء
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The aging behavior is investigated for thin films of atactic polystyrene through measurements of complex electric capacitance. During isothermal aging process the real part of the electric capacitance increases with aging time, while the imaginary part decreases with aging time. This result suggests that the aging time dependence of the real and imaginary parts are mainly associated with change in thickness and dielectric permittivity, respectively. In thin films, the thickness depends on thermal history of aging even above the glass transition. Memory and `rejuvenation effects are also observed in the thin films.



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