Modeling of the destruction process of butyl rubber

The article is devoted to the study of the radiation destruction process of polymers using the methods of mathematical modeling. Rubbers based on butyl rubber with resin and sulfur vulcanization, which were irradiated at the 60Co source with doses of 20–100 kGy, were used as the objects of the study. The plasto-elastic properties of the reclaimed materials were evaluated by the viscosity index, which was determined on a Mooney viscometer at a temperature of 100 °C. An intensive decrease in the viscosity of all the investigated samples was observed with an increase in the absorbed dose, while the nonlinear character of the change in the viscosity index was ascertained. In order to determine the irradiation conditions which are necessary to reach the required viscosity values, a calculation method for estimating changes in the properties of rubbers has been developed. The approach that allows to evaluate the dynamics of the change in the initial moments of the molecular mass distribution function of the polymer as a function of the dose of radiation was the basis for developing a mathematical model for the destruction of rubbers based on butyl rubber under the action of gamma rays. A functional dependence was obtained that relates the Mooney viscosity to the radiation dose. The estimation of the model parameters is carried out using the genetic algorithm. The adequacy of the developed mathematical description has been confirmed. •Intensive decrease in the viscosity of rubbers occurs with increasing radiation dose.•The change in the viscosity of rubbers during irradiation is nonlinear.•The mathematical model of destruction is based on a description of the initial moments of the distribution function.