Biodegradation of poly(vinyl alcohol) in soil environment: influence of natural organic fillers and structural parameters

The biodegradation of PVA blends with natural polymers, such as gelatin, ligocellulosic by-products (sugar cane bagasse), as well as poly(vinyl acetate), was investigated in respirometric tests aimed at reproducing soil burial,conditions. The observed behavior is discussed in terms of the influence of each blend component on the overall extent of mineralization, by assuming a simple additive behavior. The collected data evidenced that the biodegradation of PVA and PVA-based materials is rather limited under soil burial conditions. Additionally, PVA depresses the biodegradation of some of the investigated blends, particularly when mixed,with gelatin. On the contrary, the hydrophobic character of the natural polymer component as well as the residual content of acetyl groups of the used PVA samples seem to have a positive effect on the biodegradation propensity of the blend.