Quality of reclaimed fibres

Seen with the user s eyes, unproved quality of reclaimed fibres means... 

As can be seen in Table 9.3, both the aerodynamic and mechanical processes of web formation raise different questions with regard to the quality of reclaimed fibres. When producing the fibres, quality parameters can be set to some degree. 

Needle-punched warp-knitted nonwoven material serves us as a further example of how important the quality of reclaimed fibres is. This material is used to substitute for the components of polyurethane foam in laminated composites. The purely textile composite resulting allows one to recycle both the production waste generated and the composite structure itself at the end of its life (see Chapter 3). To make sure a nonwoven containing 40% of reclaimed fibres can be well processed on a warp-knitting machine and shows full functionality when used as a laminated composite for a motor vehicle seat, the reclaimed fibre used needs to meet the following requirements ... 

At the point of the producer of reclaimed fibres handing the materials over to the user, it is helpful to have a syslan of quality assessment available that allows the documentation of the technological parameters of the material. It will oeate the base on which contracts can be negotiated and questions of warranty clarified between the producer and the user. Such a system should help to define the parameters below within a short time and at low-cost ... 

Geotextiles may be looked upon as an ideal field for the application of reclaimed fibres. To make them, it is important to use well-selected textile waste and to exactly tune the process parameters when breaking it up. In this way the quality requirements below can be met ... 

A comparatively new group of materials— thermoplastic elastomers or thermoplastic rubbers —combines the ease of processing of thermoplastics with qualities of traditional vulcanized rubbers, especially elasticity. Because of convenience in processing there is much interest too in blends of plastics with elastomers, which may be modified by the inclusion of filler or glass fibre. As an example, a rubber-like material that can be processed as a thermoplastic can be made by blending and melt-mixing an ethylene-propylene rubber with polypropylene. The use of such blends may be helpful when there are needs to reclaim and re-process material, and in order to obtain products with qualities intermediate between those of the main components of the blends. 

Reclaimed fibres can be manufactured from a variety of textile waste. Both quality and processability of such fibres depend on the kind of waste. Well-known are the pure sorted fibres of high-quality which are achieved from spinning-fibre waste. In contrast, reclaimed fibres made from end-of-life textiles are of much poorer quality. They will rarely be found of homogeneons fibre type. 

It is most important to have reclaimed fibres available which are of the right quality with regard to the purpose and which are cheaper than primary fibres. Quality is expected, throughout the whole production period, to constantly remain within the parameters defined. Such parameters can, and should, be documented. 

After-treatment should focus on the further enhancement of the quality parameters reached in the breaking-down process, so that the reclaimed fibres become more competitive. The steps to be taken include... 

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