Staple fibres developments

Alceru A process for making cellulosic filaments and staple fibres. The cellulose is first dissolved in an aqueous solution of N-methylamine-N-oxide. Developed by Zimmer (Frankfurt) and TITK (Rudolstadt) from 1987. A pilot plant was expected to be built by April... 

Carbacell [Carbamate cellulose] A process for making rayon filament and staple fibre. Cellulose is reacted with urea in an inert organic solvent at a high temperature to yield cellulose carbamate. This process avoids the environmental problems caused by carbon disulfide in the viscose process. Developed by Zimmer in the 1990s and piloted in Germany and Poland. Commercialization is expected by 1999. 

The use of reversible redox systems as initiators allows to intensify the periodic grafting process66,86 and to develop a continuous technology for the synthesis of modified fibres. For instance, when using such systems, the rate of AN grafting to viscose staple fibre (Table 5) may be as high as 70% PAN of the cellulose mass per minute. 

When considering the mechanism of a slash, a staple fibre yam is more resistant to slash than a continuous filament yam, as the staple fibre yams help to dissipate the force over a larger area. Hence, further blends of staple fibre high performance yams could be developed. 

As stated above, conventional synthetic fibres may be rendered inherently flame retardant during production by either incorporation of a flame retardant additive in the polymer melt or solution prior to extrusion or by copolymeric modification before, during, or immediately after processing into filaments or staple fibres. Major problems of compatibility, especially at the high tanperatures used to extrude melt-extruded fibres like polyamide, polyester, and polypropylene and in reactive polymer solutions such as viscose dope and acrylic solutions, have ensured that only a few such fibres are commercially available. A major problem in developing successful inherently flame retardant fibres based on conventional fibre chemistries is that any modification, if present at a concentration much above 10wt% (whether as additive or comonomer), may seriously reduce tensile properties as well as the other desirable textile properties of dyeability, lustre and appearance, and handle, to mention but a few. 

A further development of the OFB concept is erosion control and re vegetation blankets (ECRB). These are a combination of PA or PP staple fibre bound within two PP or PA nets. They have similar ground cover characteristics to the OFBs. However, the use of ultraviolet stabilised fibres provides for a much longer installation life than the organic blankets. 

An interesting development for thermoplastics is a technique for pulping or fibrillation that greatly increases the surface area of short-length fibres of para-aramid, and renders them suitable for reinforcement of plastics and elastomers. While a typical staple fibre will have a surface area of about 0.1 m g K the new compounding process increases this to 7-9 g, so increasing the area... 

Fibres were originally developed by ICI Fibres and the technology is now owned by Zyex Ltd in the UK. Zyex produce a wide range of monofilament, multifilament and staple fibres and can make hollow monofilaments and tubes. PEEK is the most common material but PEK and PEKK can also be used. The fibres are manufactured by extrusion and orientation and have good mechanical properties with... 

Staple fibres provide the starting point for many nonwoven processes. Because the staple-based technologies are so diverse in terms of machinery design and fibre processing requirements, a range of fibre types have been developed to suit individual needs and to ensure optimum conversion efficiencies and fabric properties. 

The development and use of Thinsulate (3 M), claimed to be based on either a polyester or polypropylene microfibre (diameter -15 pm), has become well established during the last 30 years as an effective insulative fibre, often in blends, such as the polypropylene microfibre combined with polyester staple, which has undergone extensive tests both in the laboratory and in the field. Examples of the latter include use by postmen, ski centres, and survival posts in the northern USA and in underwear for US Navy divers. Excellent results have also been recorded on a fairly recent British winter expedition to Everest. ... 

Utilizing the properties of copper, two durable platform technologies woe developed [1,13] the first one plates cotton fibres with copper oxide (Fig 1, left panel) and the second one impregnates polyester, polypropylene, polyethylene, polyur hane, polyolefin or nylon fibres with copper oxide (Fig 1, ri t panel). The fibres can be cut into short staple or produced in filament form and texturized, if so desired. The product yielded is a fibre that can be introduced at the blendii stage of yam production or directly into a woven or knit product so that no manufacturing processes are changed. Woven and non-woven fabrics can be produced. 

The dough moulding compound consists of an unsaturated polyester resin system mixed with Norwegian talc (Dolomite) and glass fibre of short staple-length (3-12 mm). The resin system has been specially developed for this purpose, as already mentioned. The mixing process itself is in two stages. 

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