Integrating Sphere-Based Ultraviolet Exposure Chamber Design for Photodegradation of Polymeric Materials.
Integrating Sphere-Based Ultraviolet Exposure Chamber
Design for Photodegradation of Polymeric Materials.
Martin, J. W.; Chin, J. W.; Byrd, W. E.; Embree, E. J.;
Kraft, K. M.
Polymer Degradation and Stability, Vol. 63, 297-304,
building construction; construction materials;
ultraviolet radiation; ultraviolet chambers; weather
The primary method for obtaining laboratory weathering
data for a wide range of commercial polymer products
including coatings, textiles, elastomers, plastics and
polymeric composites is through the use of ultraviolet
radiation exposure chambers (UV-chambers). Although
numerous improvements have been made in the design of
UV-chambers over the last 80 years, the repeatability
and reproducibility of the exposure results from these
chambers have remained elusive. This lack of
reproducibility and repeatability is attributed to
systematic errors in their design, operation, and
control which, in turn, has prevented comparisons of the
performance of competing construction materials exposed
in the same environment, comparisons of the performance
of the same material exposed in different laboratories,
and the comparison of field and laboratory results. The
paper re-examines current UV-chamber designs, discusses
possible sources of systematic error associated with
these chambers, and describes an innovative UV-chamber
design having a basis in integrating sphere technology
which greatly reduces the magnitude of these errors.