Scrap tyre rubber

Economic advantages of using ultra-fine scrap tyre rubber in virgin and recycled rubber and plastic compounds a comprehensive LCA [4]... 

A group at Jiangsu Polytechnic University [17,18] have used a twin-screw extruder to continuously devulcanise scrap tyre rubber and have studied the influence that screw speed and process temperature have on the degree of devulcanisation and the physical properties of the material once it had been revulcanised. A scanning electron microscope (SEM) was also used to study the morphology of the DR... 

Surface-modified rubber particles are commercially available [2]. At the time of writing, the rubber is derived from scrap automotive tyres. Rubber particles consisting of other types of rubber, scrap or virgin in origin, can also be surface-modified. Currently, grades of rubber particles are available in sizes ranging from diameters of 1.5 x 10 m (10 mesh) down to less than 7.5 x 10 m (200 mesh). 

A standard production thermo-mechanical reclaiming machine , designated MRR-031, has been developed by Elast-Tekhologii LLC in Russia [20,21]. This machine is capable of reclaiming rubber from scrap tyres and GRG based on SBR, polyisoprene, EPDM and butyl rubber. The reclaimed rubber has been incorporated back into new rubber compounds at a replacement level of up to 90% of virgin rubber polymer. The physical properties that are reported for various... 

Ondrey G. and T. Kamiya. 2002. Pyrolysis gets aU fired up. Chem. Eng. 109 27-31. Sept. 2001. New pyrolysis technique adds value to tyre scrap. British Plastics Rubber. September. 86. 

Strenuous efforts are being made to market various waste materials as fillers for plastics, with varying degrees of success. They include fly ash from power stations, newsprint and various agrowaste products. In the past five years Asian organisations have promoted empty fruit bunch fibres, oil palm mesocarb fibres, rice husk ash and various nutshells. Scrap rubber crumb from used tyres has also been evaluated by Composite Particles, Inc. for use in mouldings, foams and pipes. 

A study has been carried out to discover where the scrap rubber on the roads comes from. It is claimed that a good portion of the rubber comes from new tyres and not retreads, and that practically all the rubber comes from truck tyres. The main reasons for this are overloading, incorrect tyre pressure and mismatching of dual tyres. USA... 

In another study [5], scrap rubber was pyrolysed to a limited degree and the product used as a filler in new compounds. In this case, tyres were pyrolysed by a low-temperature cracking process under slightly elevated pressures to generate a solid, powdery product. This powder was then incorporated at two levels (50 and 75 phr) into SBR and natural rubber (NR) compounds that were vulcanised and then tested to obtain properties such as heat ageing characteristics, mechanical strength and viscosity. In addition to the solid powder, this process also generated an oil product that had the potential to replace conventional hydrocarbon oils as a softener and extender in rubber compounds. 

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