Abstract: A process for activating vulcanized waster rubber particles by treating the waste rubber particles with a rubber latex and a curing system and drying the treated waste rubber particles. The waste rubber particles are preferably treated with 1 to 4% by weight of rubber latex (calculated as dry substance) and 0.5 to 3% by weight of sulfur as vulcanizing agent, both being calculated on the waster rubber particles. The treatment is carried out conveniently by mixing the waste rubber particles with the vulcanizing agent, adding the latex at a temperature of from 70.degree. to 90.degree. C. and stirring the obtained mixture for 5 to 10 min. so as to evaporate the water. Also disclosed are processes for producing a rubber-like article by molding the activated waste rubber particles, whether or not mixed with a non-vulcanized rubber compound, while applying heat and pressure.
Abstract: Thermoplastic elastomeric compositions are prepared by mixing comminuted vulcanized rubber having a mean particle size of below 1.5 mm with a thermoplastic olefin or diolefin polymer, particular polyethylene, at a weight ratio of from 1:3 to 3:1, and with a non-ionic surfactant in an amount of 0.1 to 5 wt. % referring to the total amount of polymers. The addition of a non-ionic surfactant greatly improves the bonding between the two main components, thus yielding compositions of a very low level of porosity and improved mechanical properties, particularly superior thoughness.The compositions can be moulded or extruded to a variety of products, such as profiles, roofings, fencing posts, pallets, and also shoe sales, saddle covers, solid tires, sprinkling funnels, etc.