Biodegradability of PP/PHBV (70/30) blend films

This study aimed to investigate the biodegradation of polypropylene/ poly(hydroxybutyrate-co-hydroxyvalerate) (PP/PHBV) blend (70/30, w/w) films in soil, monitoring the evolution of CO2 using the respirometric method. The polymeric films were incubated at 28°C ± 2°C for 180 days in biometer flasks, and the sequence of biodegradation percentage was PP/PHBV (70/30) > PP, that is, 15% and 0%, respectively. Fourier transform infrared spectroscopy and X-ray diffraction measurements showed that biodegradation occurs in the blend PP/PHBV interphases. Preferentially, the microbial action occurs in the fraction of the biodegradable polymer (PHBV), and it influences the PP fraction morphology, which showed some significant changes in the monomer unit sequences and the organization of the chains. © 2013 Wiley Periodicals, Inc.