| Popis: |
The photodegradation of poly(tert-butyl methacrylate) films under 100 ppm sulfur dioxide in air or 100 ppm nitrogen dioxide in air and in mixtures of the gases in air, at constant temperature (30°C) and humidity (30%), was studied. In the presence of sulfur dioxide and nitrogen dioxide under irradiation the polymer shows a rapid degradation, while the thermal degradation is very small, as well as the photodegradation in air. The measured effect of photodegradation of thin films was stronger than that of thicker films. An equation was derived to characterize the degradation by an autoacceleration and a linear part. FTIR spectroscopy shows the formation of carboxylic acids. |
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