Harmonization and Optimization of Weathering Test Methods for Building and Construction Sealants and Adhesives

Sealants and adhesives play a vital role in building engineering and are expected to perform well for at least 20 years. However, many fail prematurely, partly because of inadequate information on their long-term resistance to the effects of solar radiation, heat/cold, moisture, atmospheric pollutants and mechanical strain. The laboratory accelerated weathering tests, a necessity for determining in a short time whether products are suitable for the intended use, often fail to identify products with poor in-use performance. The validity of the test results depends on optimization of the test parameters so that aging effects of field conditions on sealants can be closely simulated. Simulation of the spectrum of solar radiation by the artificial light source is a critical factor. Simulation of the temperature, amount and type of moisture and mechanical strain that sealants experience under use conditions is also significant.