What is rubber recycling?
Rubber recycling describes various processes for the recycling of rubber products and rubber waste. vulcanised Elastomers in general. The aim of recycling is to use the material as a raw material or filler in new products. The process helps to conserve resources and reduce waste, but it is not a viable option for the majority of elastomers. Elastomers technically demanding. One exception is Thermoplastic elastomers.
Why is rubber recycling challenging?
In contrast to thermoplastics, rubber cannot simply be melted down, as it is characterised by the Vulcanisation becomes a permanently elastic material. This makes recycling both mechanically and chemically more complex.
Common recycling processes for rubber
- Mechanical recycling: In mechanical recycling, the vulcanised rubber is shredded and processed into rubber powder or granulate (e.g. from used tyres). The granulate obtained is then used as a filler, pressed into soft floor coverings or anti-slip mats or utilised as a bitumen admixture.
- Devulcanisation: During the Devulcanisation the sulphur bridges in vulcanised rubber are specifically broken up in order to return the material to a partially processable state. The resulting recyclate can then be used as a component of new rubber compounds, but usually only in limited proportions, as the mechanical properties are reduced compared to virgin material. Devulcanisation can be carried out thermally, mechanically, thermo-mechanically or chemically.
- Depolymerisation: In the Depolymerisation the polymers are broken down via a chemical reaction using catalysts and/or heat. Depolymerisation has hardly been used on an industrial scale to date, as the costs are not in proportion to the benefits.