- 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.