Reinforced thermoplastics recycling

Recycling more effective solutions are sought. The development of the mono-material concept is favourable to thermoplastics and self-reinforcing thermoplastic composites such as self-reinforced polypropylene (Curv from BP). 

Sheets of recycled fibre-reinforced thermoplastics (Haller Formholz). 

For a high-performance glass fibre reinforced thermoplastic such as PEEK, the retention of modulus and strength after two and four recycling cycles are in the ranges of 79-87% and 76-84%, respectively. 

Fibre-reinforced thermoplastics, such as glass fibre-reinforced nylon, are increasingly used as substitute for wood, metallic or ceramic materials in applications for which high strength and temperature are not decisive parameters. They are being incorporated into components in the automotive, naval, sport and leisure industries due to the potential of reduced production costs of lighter parts and recycling possibilities. 

An important aspect of the composite world is the issue of recycling [4]. Kemmochi et al [5,6] examined the possibility of closed loop material recycling for fiber reinforced thermoplastic composites and Allred et al [7] have developed a tertiary recycling process. 

Kemmochi K, Takayanagi H, Nagasawa C, Takahashi J, Hayashi R, Manifestation models for closed-loop material recycling in carbon fiber reinforced thermoplastics (CFRTP), High Technology Composites in Modem Applications, Paipetis SA, Youtsos AG eds., 203-213, Sep 1995. 

The use of natural fiber reinforcements in recycled thermoplastic polymers has generated considerable research interest due to the increasing environmental threat created by the high consumption rate of petroleum-based plastics. Therefore, there is a growing interest in the development of green, environmentally-friendly composites for agro-based structural materials. Apart from this, the renewed interests in recyclability and environmental sustainability have also arisen in the last few years. The best possible way to develop such composites are to incorporate natural fibers into recycled... 

An exceptional advantage of self-reinforced thermoplastic composites is that they can be thermally recycled, but also reprocessed due to their polymer purity. This can be done by either returning the composite to a melted state or by simply re-granulating it. Thus, this process does without the complicated and expensive separation of the components, because an actual single-material system is on hand. Such a simple and useful recycling concept (in regard to material reuse) for the quantities currently in circulation has yet to be developed for the established foreign fiber reinforced thermoplastics. 

In the USA, the use of filled thermosets and thermoplastics in panels is expected to increase significantly over the next few years. In Europe, the use of thermosets in vehicles is expected to be flat or decline, primarily because of competition from reinforced thermoplastics, which are considered to be easier to recycle. 

Recycling of glass fibre-reinforced plastics is reviewed, with special emphasis on remelting of thermoplastic composites, mechanical recycling of thermoset composites, depolymerisation and dissolution of thermosets and thermoplastics, closed loop recycling of glass, and the use of glass as a mechanical compatibiliser. 32 refs. 

Journal of Thermoplastic Composite Materials 7, No.l, Jan.l994,p.64-74 NEW DEVELOPMENTS IN CHEMICAL RECYCLING AS A SINK FOR PROBLEMATIC WASTE FROM FIBRE-REINFORCED PLASTICS Menges G... 

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