The effects of pH and biodegradation on polymer-based granules

Abstract: The use of biopolymers instead of traditional fossil fuel based and non-biodegradable polymers is seen as a positive step forward towards a more environmentally friendly future. This project investigates a granule product that is used in a dishwashing system with the aim of gaining knowledge about how it is affected by the storage in between uses and its biodegradability. The product is based on a known biodegradable polymer which is partially biobased. Experimental tests were performed to explore the effect of different pH values, in the pH range of foods, to give insight into how the granules could optimally be stored in between uses. Furthermore, biodegradation screenings were performed to investigate disposal options for the granules after they have been used. The results showed that a neutral pH value, 7, is preferred over a low pH, 3, during storage to minimize negative effects on the granules. Results from the biodegradation tests showed that the product is more degradable under aerobic conditions (in aerated soil and compost) than under anaerobic conditions (in anaerobic sludge). This could be further explored when looking into disposal options for the granules, but the relatively slow rate of degradation may be an obstacle.