Fibres mixing with plastics

Other uses of core kenaf fibre include also soil-less potting mixes, animal bedding, oil absorbents, packing material, organic filler for plastics, drilling mud binder, grass and flower mats, decorative fibres and insulation as well as animal feed and human food [41]. Bast fibre is also blended with cotton and used in textiles [41]. The bast fibre of kenaf can also be mixed with plastic for injection moulding. 

Optical fibres composed of plastics are also transparent in the visible spectral region but optical losses reach 102 - 103 dB/km13. Their refractive index varies from 1.35 to 1.6 depending on the kind of polymer used (e.g. polymethymethacrylate PMMA -1.49). The chemical resistance is much worse than that of silica fibres and thermal stability is incomparable. On the other hand, low temperature processes of plastic fibre preparation allow us mix the starting polymer with organic dyes which enables the production of luminescent fibres suitable e.g. for fluorescence-based sensing13. 

Silica powder, glass beads and fibres are commonly used for the reinforcement of plastics. The produced composite materials have an increased thermal and mechanical stability, compared to the pure polymeric material. In order to bind the inorganic filler to the organic matrix, silane molecules, with both an inorganic and organic side, are used. The silane may be mixed with the matrix and filler material in the composite preparation, or be coated onto the filler prior to mixing. The application... 

Maleic anhydride is used as a chemical intermediate in the synthesis of fumaric and tartaric acids, certain agricultural chemicals, resins in numerous products, dye intermediates and pharmaceuticals [2]. It is primarily used as a co-monomer for unsaturated polyester resins, which are used in the production of bonding agents for plywood manufacture and when mixed with glass fibres for reinforced plastics. Annual production of maleic anhydride is estimated to be over one million tormes [3]. 

As already stated, there are many different methods of processing plastics, according to the material used and the desired finished product. Plastics are wonderful materials for shaping. They can be made into flat sheets, or they can be reinforced with fibres. They can be blow moulded and made into hollow objects such as drinks bottles, or they can be thermoformed for making food cartons. There is a variety of processes for the different synthetic plastics, but all of them start with the required chemicals in pellet, powder or liquid form. These are melted, mixed with additives, heated and shaped. 

Hydrocarbon and mineral oils are used to coat cellulose, glass, asbestos, or mineral wool fibers. Composition of the plasticizer and fibers is then mixed with the polymer matrix, with which the plasticizer is also compatible. As a result, ordinary polymer mixing equipment such as mills and internal mixers can be used, with economically acceptable mixing times under mild conditions, to prepare homogeneously dispersed fibre-polymer compositions. Frequently this process is used to obtain homogeneous dispersion of fibers but also to protect fibers or glass bubbles from mechanical damage. 

Glass fibres, carbon fibres, graphite fibres and aramid fibres account for most of the reinforcements found in plastic composites. In the large-scale production of consumer-orientated composite products, hybrid composites are used in which glass fibres are mixed with... 

Reclaimed fibres mixed together are one example of how multi-material composite systems can be used. Compacting as in the recycling of plastic materials is another one. The agglomerate achieved this way, however, faces problems with regard to marketing. 

For the composition of the mix used, we take into account the workability of the material, choosing a low fibre percentage (0.5 X of volume) and a plastic consistency (W/C - 0.5 with plasticizer, sand Max Dia - 3.15 mm, C = 535 kg/m ). Among the various techniques of placing fibre reinforced concrete, we used pouring method. 

Artificial fibres are as much in common use as the plastics and have equally interesting histories, as documented in Jenkins (2003). One of the first artificial fibres was rayon, the starting point for which is cellulose from wood pulp. It was first discovered in 1855 and was commercially produced by 1924 in the USA. Rayon is produced in two stages. First, cellulose is mixed with sodium hydroxide and carbon disulphide to produce viscose which, as its name suggests, is a thick, sticky liquid. As in the case of Terylene, the viscose is then forced through fine holes in a cylinder (a spinneret) as a jet and into dilute sulphuric acid to produce rayon. This is a fine, almost silky thread with multiple uses which include textiles, tyres and carpets. 

The testing does not yet allow for setting specific input criteria. However, the testing made clear that the process probably can handle a broad spectrum of materials, such as wood, biomass, mixed plastic and pure PVC waste. For instance tests have been done on PVC waste but also with a mixture of PVC, PE, other polymers, Cu, Al, chalk, cement and fibres. 

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. 

Objects for medical purposes made of plastics which are to have an antimicrobially active content of metals (or metal compounds) can be economically produced in that a plastic blank in foil, granulate or fibre form is coated with the desired metal (or metal compound) by the thin-film technique. The intermediate product thus obtained is then ground and mixed and processed further as the raw material for the desired final form. Sueh objects are thus antimicrobially active all over their surfaces and also on inner surfaces. Hence the full effect of the antimicrobially active substances, in this case oligodynamically active metals (or metal compounds) is obtained with only a small fraction of the quantities formerly required when they were included in the plastic in powdered form, thus resulting in considerable cost savings. 

An optimal combination between aerodynamic and weight requirements was achieved for the Transrapid by modular hybrid (mixed) construction methods. For example, the glass-fibre-reinforced plastic (GRP) front module is designed for maintaining aerodynamic pressure as well as for stability under cross wind forces of 500 km/h, and is bonded to the front of the aluminium structure of the rail cars with Sikaflex products (Fig. 5). 

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