Biodegradable plastic designed to improve the soil quality and microbiological activity

Publication date: Available online 28 October 2018Source: Polymer Degradation and StabilityAuthor(s): Amanda Aleixo Moreira, Suzana Mali, Fabio Yamashita, Ana Paula Bilck, Maria Tereza de Paula, Aline Merci, André Luiz Martinez de OliveiraAbstractBiodegradable plastic composites were produced from mixtures of polyvinyl alcohol (PVA) and starch, which were mixed with different natural fillers [sugarcane bagasse (SB), oat hulls (OH) or silkworm exuvia (SE)] and nutrients to stimulate the biodegrading microbiota. The physicochemical and biodegradability characteristics of the produced materials were studied, in addition to their influence over the microbiota involved in biodegradation. The SB-composite showed reduced solubility in water, a lower water absorption capacity and a slower mineralization rate when buried in a commercial substrate for seedlings production, as compared with those of the OH- and SE-composites. Scanning electron micrographs demonstrated the increased colonization of materials by the biodegrading microbiota over time, which were predominated by filamentous fungi in OH- and SE-composites, while the SB-composite was predominantly colonized by bacteria. A Fourier transform-infrared spectroscopy (FT-IR) analysis of the biodegraded materials highlighted the chemical differences in the protein and carbohydrate content between formulations, corroborating the activity of different microbial groups on their mineralization. Regardless of its composition, the minera...
Source: Polymer Degradation and Stability - Category: Chemistry Source Type: research