TESTING AND EVALUATING COMMERCIAL APPLICATIONS OF NEW SURFACE-TREATEDRUBBER TECHNOLOGY UTILIZING WASTE TIRES

Standard, untreated, crumb rubber typically commands a low selling pri ce, usually $0.33-0.66/kg. This low value has limited the full recover y of the rubber from waste rubber products, An emerging technology inv olving the surface treatment of rubber particles with chlorine gas may improve the characteristics of waste rubber so that it can be used in high-value products, which could support a higher price for treated r ubber. This research identifies the two most significant end-use marke ts for treated rubber particles: footwear (shoe soles and components) and urethane-foam carpet underlay markets. In these major markets, res earch has clearly demonstrated that two categories of surface-treated rubber particles can be used easily in existing manufacturing plants a nd processes and has shown that the material meets or exceeds existing standards for performance, quality, and cost-effectiveness. The combi ned market potential of the surface modified rubber particles is estim ated to be 10(8) kg/yr. The current price of the surface-treated mater ial is estimated to be $1.10-1.43/kg, which could be economically sust ained in these high-value applications. Modifying the surface of scrap tire rubber may also yield substantial energy savings, The modified s crap rubber may also contribute greatly to the use of postconsumer scr ap-tire waste as a higher value material in polymer compounding. One b arrier is moisture in the surface-treated rubber material (0.8-1%), wh ich is curtailing the commercial success of surface-treated rubber par ticles in urethane-molded products. Further development is under way t o correct that problem.