No abstract

In order to make bioplastics accessible for a wider spectrum of applications, ready-to-use plastic material formulations should be available with tailored properties. Ideally, these kinds of materials should also be “home-compostable” to simplify their organic recycling. Therefore, materials based on PLA (polylactid acid) and PHB (polyhydroxybutyrate) blends are presented which contain suitable additives, and some of them contain also thermoplastic starch as a filler, which decreases the price of the final compound. They are intended for various applications, as documented by products made out of them. The produced materials are fully biodegradable under industrial composting conditions. Surprisingly, some of the materials, even those which contain more PLA than PHB, are also fully biodegradable under home-composting conditions within a period of about six months. Experiments made under laboratory conditions were supported with data obtained from a kitchen waste pilot composter and from municipal composting plant experiments. Material properties, environmental conditions, and microbiology data were recorded during some of these experiments to document the biodegradation process and changes on the surface and inside the materials on a molecular level.

According to Directive (EU) 2019/904 of the European Parliament and of the Council of 5 June 2019, singleuse plastic cutlery, cotton buds, straws and stirrers will be banned in the member states of EU from summer 2021 onwards. Many of them are being replaced by compostable products. The aim of the research was to assess the biological disintegration of selected single-use products under real conditions of urban composting facility. All tested products are established for the Slovak market as 100% compostable by a composting facility. The eight selected products from five different producers were placed into a composting pile of the urban composting facility for 12 weeks. The samples were visually inspected on a regular basis. Temperature and humidity of the pile were continuously measured at the same time. Three samples from each kind of tested product were analyzed, 3 pieces of filter paper were used as the reference samples. The research showed that all tested products were completely or partially disintegrated during the considered period. The average degree of the disintegration of 90% was not reached for one producer only.

This study focused on material recycling of a biodegradable blend based on PLA and PHB for multiple applications of biodegradable polymeric material under real conditions. In this study, we investigated the effect of multiple processing of a biodegradable polymer blend under the trade name NONOILEN®, which was processed under laboratory as well as industrial conditions. In this article, we report on testing the effect of blending and multiple processing on thermomechanical stability, molecular characteristics, as well as thermophysical and mechanical properties of experimental- and industrial-type tested material suitable for FDM 3D technology. The results showed that the studied material degraded during blending and subsequently during multiple processing. Even after partial degradation, which was demonstrated by a decrease in average molecular weight and a decrease in complex viscosity in the process of multiple reprocessing, there was no significant change in the material’s thermophysical properties, either in laboratory or industrial conditions. There was also no negative impact on the strength characteristics of multiple processed samples. The results of this work show that a biodegradable polymer blend based on PLA and PHB is a suitable candidate for material recycling even in industrial processing conditions. In addition, the results suggest that the biodegradable polymeric material NONOILEN® 3D 3056-2 is suitable for multiple uses in FDM technology.