Title: Contribution to Reducing the Test Time for Determining the Long Term Stability of Sealants
Author(s): Till Boettger and Hartmut Bolte
Publication: Symposium Paper
Appears on pages(s): 937-954
Keywords: Chemical properties; polyurethane resins; sealers; silicone resins; tensile strength; tests.
At present, in our research group at the University of Leipzig the following tests are being carried out on selected elastomeric sealants (polysulphide. polyurethane. silicone. and for comparing EPDM and polychloroprene): alternate aging with fluorenscent UV lamps alternate aging with xenon arc lamps thermal aging open air weathering room storage We characterise the change in materials properties through mechanical test methods (tensile strength and elongation at break). thermoanalysis (DSC) and chemical spectroscopy (FT-IR. PAS). The intermediate evaluation of the results shows, that the similarity of the curves of artificial aging and the open air weathering is clearly visible. Additional series of tests have been started with the following goals: prolonging the stress period for artificial aging, so as to better evaluate the long-term curve raising the stress temperature so as to reduce the test time combination of artificial weathering with acid rain combination of artificial weathering with extension and compression verification trials on joint models The tests should be continued until a rapid aging method is found, which produces virtual agreement with that of natural aging.