Solar Energy, Vol.84, No.5, 755-762, 2010
Aging behavior and lifetime modeling for polycarbonate
In this paper, polycarbonate (PC) as a material candidate for solar absorber applications is investigated as to the aging behavior at different temperatures in air and water. The aging conditioning was performed in air in the temperature range from 120 to 140 degrees C and in water between 70 and 95 degrees C. Tensile tests were performed on unaged and aged PC film specimens at ambient temperature using strain-to-break values as a performance indicator for the degree of aging. For PC the effect of aging was found to strongly depend on the aging conditions. Activation energy based lifetime prediction models according to various methods described in the literature were applied. The activation energies and corresponding lifetime predictions for the temperature range from 40 to 60 degrees C in water and from 90 to 110 degrees C in air derived from these models are compared and interpreted as to their practical relevance. (C) 2010 Elsevier Ltd. All rights reserved.