Maximilian Lackner
Vulcanized Rubber, as elastomer, is difficult to recycle. Today, the main end of life routes of tyres and other rubber products are landfilling, incineration in e.g. cement plants, and grinding to a fine powder, with huge quantities lacking sustainable recycling of this valuable material. Devulcanization, i.e. the breaking up of sulfur bonds by chemical, thermo-physical or biological means, is a promising route that has been investigated for more than 50 years. The rubber material thereby suffers mechanical degradation and a loss in mechanical properties.A novel process of thermo-mechanical devulcanization in a twinscrew extruder is presented, which includes long-chain branching to “repair” the polymer. Process control can be done via melt pressure measurement or an online rheometer. The novel process has the potential to save up to 2kg of CO2 per kg of rubber.
