Home – Home – Jornals – Chemistry for Sustainable Development 2017 number 4

The paper studied the effect of conditions of oxidative treatment of comminuted rubber with nitrogen (I) oxide (the so-called ketonization) obtained by mechanical grinding of truck and passenger tires on the main characteristics of the resulting regenerate samples. As established, treatment of comminuted rubber with the initial amount of nitrogen (I) oxide of 2 mol for 1 h or 1 mol for 6 h at the process temperature of 230 °С ensured obtaining the regenerate with the optimum ratio of oligo- and macromolecules containing statistically distributed С=О groups. The reactive oligomeric component formed in the technical synthesis process provides the regenerate with the level of rheological properties required for the use in the content of elastomeric compositions. The presence of functional groups in the oligomer and polymer components of pilot regenerate samples leads to a decrease in the induction period of vulcanisation, which is driven by the acceleration of the formation process of a benzthiazolyl radical arising during decomposition of a vulcanisation accelerator and by the involvement of free sulphur that enters into regenerate composition into the vulcanisation process. The found character of the influence of pilot regenerates on structurisation processes of carbon-chain polymers allows carrying out the optimisation of the content of compositions in which it is planned to use the regenerate, and also adjusting technological modes for vulcanisation of rubber mixtures. As demonstrated in the carried out comparative study of strength-elastic properties of the pilot and industrial regenerate samples, vulcanisates based on trial regenerate samples had high conditional tensile strengths at 200 % elongation. The resulting effect of an increase in strength is reached due to a more homogeneous distribution of the applied load and realisation of orientational phenomena in a low-modulus elastomeric matrix.