Conductive rubber with the effect of positive temperature resistance from the tire regenerate

Abstract

The possibility of developing conductive rubber based on tire regenerate and conductive carbon black OMCARB CH85 is shown. The vulcanizing characteristics of the regenerates obtained by thermomechanical devulcanization using a curing group and conductive carbon black were studied. It is shown that after thermomechanical devulcanization, preservation of sulfide bonds, re-vulcanization occurs only in the presence of sulfur and vulcanization accelerators. A flocculation effect was detected upon the introduction of OMCARB CH85 into the regenerate.It is shown that tensile strength and Shore A hardness are increase with an increase in the content of conductive carbon black in the regenerate. However, there is insufficient dispersion of carbon black, a decrease in elongation at break and resistance to abrasion is observed. The study of volume resistivity showed that the resulting rubbers belong to semiconductor materials. The dependence of resistivity on temperature in the range from 10 to 80 °C is constructed. It is shown that the effect of a positive thermal coefficient is observed in all samples. The values of the positive temperature coefficient of resistance in the temperature range of 10 – 80 °C are 0.054 – 0.285 deg–1.