摘要：

A vivacious discussion about the possibilities of rubber recycling took place during the Nineties, followed by a period of reduced activity in this field. But the problem of rubber waste is still pressing. Recently, this topic attracted the special attention of the EEC, supporting all involved parties in finding an environmental-responsible solution for this problem. The rubber recycling history is dating back to the early years of the rubber technology itself; and during the former century different approaches have been followed in order to make this material re-usable. The cured rubber has been used as a granulate in simple rubber products such as mats or sheets, or in low-quality rubber compounds for similar purposes. The technology used for grinding the rubber and separation of contaminants has been improved as a reaction on the increasing quality requirements in terms of homogeneity and purity for rubber powders and granulates. The next step in upgrading this material is a breakdown of the vulcanization network, an attempt to convert this material into its original unvulcanized state, as far as possible. Different reclaiming processes have been developed, not all of them fulfilling the strict requirements in terms of quality, homogeneity and costs. Nowadays reclaim is widely used in rubber compounding including high-quality tire compounds, taking advantage of the positive influence on the processing behavior of the material. Another possibility for the modification of a particulate rubber in order to achieve a better bonding to a polymer matrix, is a surface activation. Several concepts of surface activation have been developed like a superfacial breakdown of the crosslinks -mechanically or chemically - or a coating with a curing system and/or a crosslinkable polymer. The application of this recycling product ranks between untreated rubber crumb or powder and reclaimed rubber. The article contains a comparative overview of the most interesting techniques for recycling of rubber waste and examples of applications of these products.

展开