Photodegradability testing of cellulose acetate filters – outdoor weathering vs. accelerated weathering
Degradation testing in the laboratory is based on understanding a material’s exposure to specific environmental forces, which can play a key role in the mechanisms of degradation. Cellulose acetate filters can be degraded by various environmental forces, which include physical forces, biological processes, heat, light, and water. These various forces can lead to degradation mechanisms, such as photodegradation, biodegradation, chemical degradation, dispersion, and disintegration.
For this study, the testing was focused on the photodegradation mechanism of cellulose acetate filters by two different tests. An accelerated test method, based on the 1995 CORESTA Task Force utilising bench top weatherometers and a roof top weathering test method was used. A comparison of the results for accelerated bench top testing and roof top testing showed that one week of accelerated testing is equal to one month of roof top testing. Also, the impact of paper on the filter versus removed from the filter was studied. It was determined that the impact of paper on the rate of photodegradation was larger for samples which had photodegradation enhancing additives incorporated into the cigarette filters. These findings indicate that care should be taken in understanding the test method for the specific degradation mechanism being investigated.