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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.

Styrene–butadiene rubber and acrylonitrile–butadiene rubber as elastomer matrices were filled with barium ferrite in order to prepare rubber magnetic composites. For cross-linking of rubber compounds, peroxide curing systems consisting of dicumyl peroxide as curing agent and four types of low molecular weight organic compounds as co-agents were used. The work was focused on the investigation of different types of co-agents on the cross-linking, physical-mechanical and magnetic properties of the prepared composites. The results revealed that the type and amount of co-agent has no influence on magnetic characteristics of composites. On the other hand, cross-link density and physical-mechanical properties were significantly dependent on the composition of curing system. Co-agents contribute to the improvement of adhesion on the interphase filler-rubber. Considering the type of rubber matrix, higher values of tensile strength exhibited composites based on acrylonitrile–butadiene rubber. As magnetic filler and co-agents are polar materials, their compatibility with polar elastomers like acrylonitrile-butadiene rubber is much higher when compared to no-polar elastomers like styrene–butadiene rubber. © 2019, Pleiades Publishing, Ltd.

Barium ferrite in constant amount (50 phr) was incorporated into styrene-butadiene rubber to prepare rubber magnetic composites. Dicumyl peroxide was used as a curing agent for cross-linking of the prepared composites. Four different types of low-molecular-weight organic compounds were applied as coagents to enhance the efficiency of cross-linking process and to improve the compatibility between the rubber and the filler on the interphase. The main goal of this work was to investigate the influence of the composition of peroxide curing system on cross-link density, physical–mechanical and magnetic properties of the composites. The results revealed that the type and amount of coagents have no influence on magnetic properties of the rubber magnets. On the other hand, cross-link density and physical–mechanical properties were significantly dependent on the composition of curing system. The increase of tensile strength can be attributed to the improvement of adhesion on the interphase filler–rubber due to the presence of coagents. © The Author(s) 2019.