BENEŠOVÁ Pavla Brno University of Technology

Biodegradability Testing of Modified PHA-based Nanomaterials by Standard Test

Co-authors OBRUČA Stanislav, WURSTOVÁ Agáta, KUNDRÁT Vojtěch, MÁROVÁ Ivana

Polyhydroxyalkanoates (PHA) are produced from renewable carbon resources by some microorganisms belonging to the Bacteria and Archaea domains of life. Mechanical properties of PHAs make them suitable replacements for petrochemically produced bulk plastics (polyethylene, polypropylene etc.), but in contrast to these commodity plastics PHA are completely biodegradable to carbon dioxide and water without formation of any toxic byproduct. PHAs are environmentally compatible polymeric material and can be processed into films and fibres. PHAs are naturally degraded by intracellular and extracellular PHA depolymerases. The work was aimed at comparison of biodegradability of PHB nano-fibre material with different forms of PHA films. For biodegradability testing standard biodegradation test described in IS/ISO 20200 norm was chosen. Degradation test was performed in thermophilic conditions. Poly(3-hydroxybuytyrate), produced from waste frying oils by Cupriavidus necator H16, was tested in following forms: i. PHB nano-fibrous material formed by electro-spinning. ii. PHB processed into film by extrusion iii. PHB processed by extrusion and modified by commercially available plasticizer. In comparison with the PHB films nano-fibres exhibited the highest degree of degradation in the shortest time. Anyway, all of the samples were completely degraded during four weeks of standard biodegradation test.