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Author
Martin, J. W. | Waksman, D. | Bentz, D. P. | Lechner, J. A. | Dickens, B.
Title
Preliminary Stochastic Model for Service Life Prediction of a Photolytically and Thermally Degraded Polymeric Cover Plate Material.
Coporate
National Bureau of Standards, Gaithersburg, MD
Book or Conf
Durability of Building Materials and Components, 3rd International Conference. Proceedings. Volume 3. VTT Symposium 50. Technical Research Centre of Finland. August 12-15, 1984, Espoo, Finalnd, Sneck, T.; Kaarresalo, A., Editors, 549-568 p., 1984
Keywords
polymers | molecular weight | degradation | thermal degradation
Identifiers
photolytic degradation; polymer degradation; polymer photooxidation; stochastic model
Abstract
A preliminary stochastic model has been developed and partially validated for predicting the service life of a polymeric film, such as poly(methyl methacrylate) (PMMA), which is subjected to both thermal and photolytic degradation. The exposure conditions under which degradation is induced simulate those expected for a polymeric cover plate material in an active solar collector. Service life for a population of films is defined as that time beyond which an unacceptable portion of the population fails. The criterion used for failure of a film is that its number average molecular weight has fallen below a specified thershold value.