Estudo da degradação do canudo de refrigerante (PP) com aditivos degradantes em solo compostado

Abstract

The present work aims to study the degradation of three types of polypropylene (PP) straws composted in a favorable environment. The study materials have specific additives that help in the degradation originated by microorganisms, and one of them has no degrading additives (normal PP). One of these additives known as an oxybiodegradant, and the other is an organic additive that has the function of forming a biofilm on the polymer surface. The degradation properties of the three study materials are compare. At first, the straws were composted in a composting chamber and, at scheduled times, samples were taken to verify their properties. Extracted samples were weighed and tested in the tensile test, which showed results of mass losses and reductions in mechanical properties. In DSC analysis, the samples containing degrading additives showed their behavior in polymer degradation. The pro oxidant additive played an important component in reducing chain sizes while the organic additive facilitated the infiltration of microorganisms into the material. In TGA, the samples with the pro oxidant additive showed evidence of residues at 500 oC, which indicates the presence of metals in the material. In the optical micrographs, several voids were looked on the surface of the samples, which it are note that these defects increased in quantities and in sizes over the composting period. However, the tests performed proved that the studied straws containing degradation additives showed higher degradations than straws without degradation additives in composted soil environments.