Thermoelastoplastics Based on a Mixture of Thermoplastic Polyolefins and Butyl Rubber

Resumo

This paper presents the results of a study of the effect of the butyl rubber and dicumyl peroxide concentrations on the strength and thermophysical properties of polymer mixtures based on thermoplastic polyolefins. The principal possibility of synthesizing thermoplastic elastomers with predetermined physical and mechanical characteristics is shown. The butyl rubber concentration is varied from 0 to 50 wt %, and the dicumyl peroxide concentration is varied from 0.5 to 2.0 wt %. It is experimentally established that, in the process of studying the deformation–strength properties for thermoplastic polyolefins, the appearance of tensile yield stress and ultimate tensile stress is typical. However, as the concentration of butyl rubber in the thermoplastic composition increases, the difference between tensile yield stress and ultimate tensile stress is sharply reduced. And, when the difference between these strength parameters disappears completely, the polymer composition starts exhibiting the properties of a thermoplastic elastomer. The additional introduction of a crosslinking agent, namely, dicumyl peroxide, into the composition of polymer mixtures promotes the appearance of a high elasticity plateau on the thermomechanical curves, which, as is well known, is characteristic of vulcanized rubbers. The most optimal concentrations of dicumyl peroxide and butyl rubber are determined, as a result of which the highest physicomechanical properties are achieved in the polymer compositions. An interpretation for the observed regularities of the change in the physicomechanical and physicochemical properties of polymer composite materials is given.