IZOD IMPACT TESTS OF UV-EXPOSED PVC PLATES
In addition to the tup tests and the projectile impact tests, a series of Izod impact tests was
also performed on a batch of notched samples made from the PVC sheet piles of one of the
manufacturers. As before, one group of samples was not exposed to any UV radiation, a second
group was exposed for 20 hours, and the third was exposed for 200 hours. Figure 38 shows these
samples individually, and Figure 39 shows all the samples. Note that the colors changed with the
duration of exposure, with the maximum discoloration for the 200-hour exposure samples.
Because the samples were made from a relatively thin (0.25-in.) sheet, the sample geometry was
different from the standard ASTM Izod test samples. Thus, the test method was similar but not
the same as the ASTM D256 test method. However, the testing allowed us to compare the
influence of UV exposure on the impact resistance of the sheet pile PVC.
Figure 38. Izod test samples: unexposed (left), 20-hour
exposure (center), 200-hour exposure (right).
Figure 39. All Izod test samples.