Polymer composite based on NBR rubber compounded with rubber waste functionalized with potassium oleate

Waste is a material that occurs as a result of a biological or technological process that can no longer be used as such. Recycling and reusing waste make it possible to contribute to environmental protection and, of course, to the protection of human health by eliminating toxins during waste incineration. The purpose of this paper is to process and characterize polymer composites based on NBR rubber (butadiene-co-acrylonitrile rubber) and rubber waste functionalized with potassium oleate in terms of rheological characteristics (to determine the optimal vulcanization time), Brabender diagrams and physico-mechanical properties in normal state and after accelerated ageing at 70°C, for 168 h (using elastomer-specific equipment). Functionalized rubber waste (with potassium oleate up to 20% at 60°C) is introduced into the mixture in proportions of 10; 20; 30; 50%. The polymeric composites based on butadiene-co-acrylonitrile elastomer and rubber waste (ground with a cryogenic mill at 10,000 rpm, at the size of 0.35 mm) were compounded on a mixer with a capacity of 350 cm3 according to the working recipes. The mixtures were supplemented with vulcanization activators and accelerators on an electric roller, resulting in formulations in the form of 4 mm thick sheets, which are then subjected to the relevant characterizations according to the standards in force for the footwear industry.