Rayon protein

A rather impressive Hst of materials and products are made from renewable resources. For example, per capita consumption of wood is twice that of all metals combined. The ceUulosic fibers, rayon and cellulose acetate, are among the oldest and stiU relatively popular textile fibers and plastics. Soy and other oilseeds, including the cereals, are refined into important commodities such as starch, protein, oil, and their derivatives. The naval stores, turpentine, pine oil, and resin, are stiU important although their sources are changing from the traditional gum and pine stumps to tall oil recovered from pulping. 

Regenerated proteins from casein (lanital), peanuts (ardil), soybeans (aralac), and zine (vicara) are used as specialty fibers. Regenerated and modified cellulose products, including acetate, are still widely used today and the production of fibers is similar to that described above for synthetic fiber production. Most regenerated cellulose (rayon) is produced by the viscose process where an aqueous solution of the sodium salt of cellulose xanthate is precipitated in an acid bath. The relatively weak fibers produced by this wet spinning process are stretched to produce strong rayon. 

The major textiles before the 1920s were wool (animal hair), cotton (a seed pod), and silk (a protein used for making cocoons). The silk spider also had a clever device in its abdomen for expelling a gel in a sac through a spinneret where reactions with air made a solid fiber with a uniform cross section. DuPont took this idea in spinning hydrolyzed cellulose into rayon fibers and scaling-the process up far beyond the needs of spiders. 

Another Arabidopsis mutant, murl, which lacks the ability to synthesize 1-fucose, possesses a defective gene encoding GDP-d-Man-4,6-dehydratase, a key enzyme in 1-fucose biosynthesis. Further analysis revealed that 1-Fuc is replaced by 1-Gal, a structurally similar monosaccharide, in the cell walls of this mutant with no adverse effects on plant physiology or metabolism (Rayon et al, 1999). Transgenic plants containing this mutation can also be used for foreign protein production. 

Macromolecular chemistry covers a particularly wide field which includes natural polymeric material, such as proteins, cellulose, gums and natural rubber industrial derivatives of natural polymers, such as sodium carboxymethyl cellulose, rayon and vulcanised rubber and the purely synthetic polymers, such as polythene (polyethylene), Teflon (polytetrafluoroethylene), polystyrene, Perspex (poly (methyl... 

As previously mentioned, the use of naturally existing polymers to produce fibers has had a long history. In the case of cellulose the results were fabulous. An initial investment of 930,000 produced net profits of 354,000,000 in 24 years for one rayon company.7 On the other hand, efforts to use another family of natural polymers—proteins—have thus far resulted in failure or at best very limited production. 

Modified rayon is made principally of regenerated cellulose and contains nonregenerated cellulose fiber-forming material, for example, a fiber spun from viscose containing casein or other protein (ASTM). This greatly increases both dry and wet strength and also permits mercerization. Rayon is readily dyed by standard methods. 

There are three types of regenerated natural fibres - rayon, acetate and protein -the first two are derived from cotton linters or pine wood. Wool like protein based artificial fibres may be regenerated from animal and vegetable proteins. 

Rexonit D. [Emkay] Protein resin mixture heavy finish for rayon and acetate fabrics. 

Early soy protein fibers resembled casein fibers, and later soy protein fibers even resembled rayon. The original intent of producing soy protein fibers was to compete with wool and silk (Moncrieff, 1975). The advantage of SPI over other protein sources was its relatively low price and high protein content. Soy protein fiber had one serious problem that was never solved its low tenacity, particularly when wet. Compared with wool, soy protein fiber was 45% weaker when dry and 75% weaker when wet. Because of its low tenacity, the best application for the fiber was in blends with other fibers such as wool, rayon, nylon, and cotton (Johnson Myers, 1995). 

Synthetic fibres, manufactured fibres can be divided into those derived from natural polymers (such as regenerated protein fibres rayon, cellulose acetates, or alginates) and those derived from synthetic polymers including nylons, polyesters, acrylics, and polyolefins. 

Some of the variants that have had some success have been spun-dyed rayons in which dye pigments are included they have excellent resistance to laundering and exposure to light. Another is an acid, dye-receptive rayon [296] for blending with wool. In this case, proteins or polymers containing NH2 groups are included in the viscose prior to spinning. 

Further, Py-GC examination of synthetic polymer fibers can often provide more data than other techniques in cases where there are minor differences in composition within a class. In contrast, fibers that are chemically very similar are difficult to differentiate by IR and Py-GC. Cotton and viscose rayon, polyesters based on PET and wool and regenerated protein, are examples of the use of these methods. 

Textile fibers (cotton, silk, wool, hair, rayon, nylon, polyester, aramid, etc.) Structural materials (lumber, composites, poly(oxymethylene), PVC, nylon, etc.) Rastios (polyethylene, polypropylene, polytetrafluoroethylene, polyoxide, etc.) Adhesives (glues, epoxies, polyvinyl alcohol, synthetic rubber, segmented polyurethanes, etc.) Biological materials (the basic molecules, carbohydrates, proteins, and DNA)... 

Biopolymers such as cellulose, starch, and proteins are available in large quantities. They can be processed into high purity products at modest costs. However, other than cotton and rayon in textiles, cellulose in paper and lumber, and a few cellulose derivatives in pharmaceutical preparations, biopolymers have been largely neglected in modern research for potential applications in polymeric materials. 

A fiber is a long, thin filament of a material. Fiber technologies are used to produce fibers from different materials that are either obtained from natural sources or produced synthetically. Natural fibers are either ceUulose-based or protein-hased, depending on their source. All cellulosic fibers come from plant sources, while protein-based fibers such as sUk and wool are exclusively from animal sources hoth fiber types are referred to as biopolymers. Synthetic fibers are manufectured from synthetic polymers, such as nylon, rayon, polyaramides, and polyesters. An... 

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