UV and soil burial degradation of irrigation tubes based on biodegradable polymer blends

Biodegradable plastic systems can potentially replace the commonly used PE ones in agriculture. Biodegradable items must ensure the same performances of the traditional ones, with the advantage to be left in soil or disposed in industrial composting plants as common organic waste. Several studies have been carried out on commercial biodegradable polymer to verify their applicability in mulching or irrigation pipes (1,2). However, the effect of UV on their performances and degradation rate in soil has not been investigated in depth. In our study, irrigation tubes based on biodegradable polymer blends were prepared by IRRITEC by a proprietary process. Commercial polylactide (PLA)/poly(butyleneadipate-co-butyleneterephtalate) (PBAT) (Bioflex) and Mater-Bi® blends were used. The polymers were characterized by rheological and mechanical point of view. Irrigation pipes were subjected to photo-aging and their degradability in soil was studied. The influence of temperature and UV irradiation on soil burial degradation was investigated.