THERMOMECHANICAL PROPERTIES OF COMPOSITES AND THEIR VULCANIZATES BASED ON HIGH DENSITY POLYETHYLENE AND COPPER

The results of a study of the effect of the concentration of finely dispersed copper and crosslinking agents on the thermomechanical properties of composite materials based on high density polyethylene are presented. It is shown that the loading of copper increases the softening temperature of composite materials. At the same time, depending on the test temperature, two physical conditions were recorded: solid and viscous. To improve the compatibility of the mixed components, maleized polyethylene was used as a compatibilizer. Dicumyl peroxide and sulfur were used as crosslinking agents. It was found that at a concentration of dicumyl peroxide of 1.0 - 2.0 wt. %, composites from a highly elastic state pass into an irreversible glassy state and lose their ability to viscous melt flow. During sulfuric vulcanization, composites filled with copper powder are characterized by three physical states: solid, highly elastic, and viscous. The optimal concentrations of reacting components are shown, and the temperature ranges of the corresponding physical states for various composite materials are predetermined. Comparative data of derivatographic analysis and thermomechanical tests are presented.