Textiles, fibers for

Vegetable fibers are classified according to their source ia plants as follows (/) the bast or stem fibers, which form the fibrous bundles ia the inner bark (phloem or bast) of the plant stems, are often referred to as soft fibers for textile use (2) the leaf fibers, which mn lengthwise through the leaves of monocotyledonous plants, are also referred to as hard fibers and (J) the seed-hair fibers, the source of cotton (qv), are the most important vegetable fiber. There are over 250,000 species of higher plants however, only a very limited number of species have been exploited for commercial uses (less than 0.1%). The commercially important fibers are given ia Table 1 (1,2). 

A major aspect of polymer, in particular polyester, production is the manufacturing of fibers for textile and technical applications. This section deals with the impact of the production conditions on the fiber quality. The following discussion will be mainly based on PET fibers, but by and large the problems, phenomena and their solutions are generally relevant to the production of other polymer filaments. 

Cellulose acetate and triacetate may be used as plastics or spun into fibers for textiles. They are made by the reaction of cellulose with acetic anhydride. 

Cellulose is sometimes used in its original or native form as fibers for textile and paper, but is often modified through dissolving and reprecipitation or through chemical reaction. The xanthate viscose process, which is used for the production of rayon and cellophane, is the most widely used regeneration process. The cellulose obtained by the removal of lignin from wood pulp is converted to alkali cellulose. The addition of carbon disulfide to the latter produces cellulose xanthate. 

The principal textile applications of hoth acetate and triacetate libels are in women s apparel and home-furnishing fabrics. Allhough the use ot acetate fiber for textile applications has generally declined, the total worldwide production tif cellulose acelate increased owing to tow lor cigarette filters. 

Cellulose is the most abundant naturally oeeurring polysaccharide formed out of glucose-based repeat imits, connected by 1,4-beta-glucosidic linkages. Cellulose and its derivatives are widely used as tough versatile materials. Cellulose nitrate, cellulose acetate (CA) and cellulose xanthate (rayon) can be easily molded or drawn into fibers for textile applications, for designing composite materials (safety glass), as thermoplastics etc [80]. 

Because reactive types of flame retardants are polymer-specific, their application is limited. There are several reactive flame retardants, specifically produced and all different in composition. For example, there is a 25% pelletized concentrate of antimony pentoxide, bromine and polypropylene resin of various melt flow indices, which is geared to PP fibers for textiles and carpets,... 

Cashmere goat soft fibers for textiles Tibet, China, Persia, Turkestan, Outer Mongolia... 

Terylene/te-ra-leen/(Tradewari ) A polymer made by condensing benzene-1,4-di-carboxylic acid (terephthalic acid) and ethane-l,2-diol (ethylene glycol), used for making fibers for textiles. 

Polyesters, such as PET are now widely used in the manufacture of fibers for textiles and other applications. While PET has many desirable properties that make it suitable for manufacturing fibers, there is a continuing need for polyester fibers that have improved properties, or properties that are different from PET, thereby opening new uses for polyester fibers. For example, PEN has found applications in high performance sailcloth materials or in industrial filtration applications. Micro fibers can be obtained from fibers using a laser thinning method. ... 

Uses Conductive fiber for textiles, coatings, and plastics industries for ESD applies. filler for thick coating where conductive powds. and small particulates fail to establish a conductivity network Features Compat. with most pastel and wh. colors Properties Lt. colored fiber < 30 diam. resist. 10 megohm-cm Elektrostat Fiber 106 [Magnesium Elektron]... 

This simple calculation gives an idea of the possible amount of coiling of the molecule. The root-mean-square end-to-end distance increases with the square root of the number of bonds, while the contour length grows linearly. To fully extend such random coil, one has to use a draw-ratio of 141 x, much more than is usually possible in drawing of polymeric fibers for textile applications which is 5- lOx. But note, that the gel-spun, high-molar-mass polyethylenes, which are discussed in Sect. 6.2.6 have a draw ratio of more than lOOx. 

Yueping W, Ge W, Flaitao C, Genlin T, Zheng L, Feng X, Xiangqi Xiaojun H (2010) Structures of bamboo fiber for textiles. Text Res J 80(4) 3 34-343... 

Humans have used all these natural fibers for textiles because of their wide availability, long fiber geometries, chemical stability, and favorable mechanical properties. The coarse texture and high mechanical properties of many bast and leaf fibers have been utilized in making common cordage fibers for rope, twine, and string [68]. 

The nomenclature of esters is relatively simple, because it is similar to the nomenclature of salts. For instance, the ester obtained from methanol and ethanoic acid (acetic acid) is called methyl ethanoate (methyl acetate). Esters are compounds that comprise a large number of structures depending on what the alcohol and acid components are. Esters with a small molecular mass are volatile substances, in most cases with a pleasant odor. For instance, butyl acetate is responsible for the odor of apples. In nature, some esters serve as pheromones for insects, for example isoamyl acetate which attracts butterflies. Other kinds of esters can be large molecules as for instanee waxes and fats where both the alcohol and the acid components can be long-ehained or eomplicated structures. These natural esters will be diseussed in the ehapter on lipids. In industry, esters are used in the fabrication of polymeric fibers for textile materials and plastic materials for various uses. The most common material is polyethylene terephthalate (PET), the ester prepared from terephthalic acid and ethylene glycol. 

The most useful synthetic fibers for textile applications are linear, semicrystalline, oriented polymers, whose properties are defined by molecular structure and molecular organization. The first level of molecular organization is the chemical structure that defines the structure of the repeating imit in the base polymer... 

Wool belongs to a family of proteins, the keratins, that also includes hair and other types of animal protective tissues such as horn, nails, feathers, beaks, and outer skin layers. The relative importance of wool as a textile fiber has declined over the past decades with the increasing use of synthetic fibers for textile products. Wool, however, is still an important fiber in the middle and upper price ranges of the textile market. It is also an extremely important export commodity for several nations, notably Australia, New Zealand, South Africa, and Argentina, and commands a price premium over most other fibers because of its outstanding natural properties. These include soft handle (the feel of the fabric), water absorption (and hence comfort), and superior drape (the way the fabric hangs). Table 2 shows wool production and sheep niunbers in the world s principal wool-producing countries. 

Poly(ethylene terephthalate) (abbreviated PET or PETE) is a semi-aromatic thermoplastic polyester obtained by condensation reaction of difunctional reactants and well-known for more than 60 years. PET is commonly produced by esterification reaction between terephthalic acid and ethylene glycol with water as a byproduct or by transesterification reaction between ethylene glycol and dimethyl terephthalate with methanol as a byproduct. In order to obtain high molar masses polymers, solid-state polymerization is carried out. PET is one of the most important industrial polymers because of its excellent properties as tensile impact strength, chemical resistance, processability, clarity, thermal stability and others. The main applications of PET are fibers for textiles, films and bottles. Annual world PET production is around 60 millions tons. PET materials were manufactured using extrusion, injection molding and blow molding techniques. 

The history of thermoplastic polyester goes back to 1929 with the pioneering work of Carothers. The first aromatic polyester of importance is poly(ethylene terephthalate) commonly abbreviated PET (or PETE) and was prepared by Whinfield and Dickson. In 1941, they created the first polyester fibers called Terylene and first manufactured by Imperial Chemical Industries (ICI). PET was produced commercially in 1953 as fiber for textile industry (Dacron) by Dupont using modified nylon technology. Dupont polyester research rapidly leads to a whole range of trademarked products as Mylar, a strong polyester film. 

The majority of the world s PET production - about 60% - is used to make fibers for textiles about 30% is used to make bottles. It s estimated that it takes about 104 million barrels just to produce the virgin polyester used in fabrics. That means most polyester - 70 million barrels worth - is manufactured specifically to be made into fibers, NOT bottles, as many people think. Of the 30% of PET which is used to make bottles, only a tiny fraction is recycled into fibers. But the idea of using recycled bottles - diverting waste from landfills - and tinning it into fibers has caught the public s imagination. 

Applications. Major applications are thermal and acoustical insulation, filtration media, and staple fiber for textiles. 

Polyacrylonitrile (PAN) is a synthetic polymer with the hnear formula (C3H3N) . Although it is thermoplastic it does not melt under normal conditions, since it degrades before melting at above 300 °C. Almost all PAN resins are copolymers made from mixtures of monomers, with acrylonitrile as the main component. It is a versatile polymer used to produce a large variety of products, including fibers for textiles, ultra-filtration membranes, hollow fibers for reverse osmosis, etc. PAN fibers are the precursor in the production of high-quality carbon fibers. 

Metall ic fibers are defined as fibers composed of metal, plastic-coated metal, or metal-coated plastic. Single-component metall ic fibers for textile usage are fine drawn filaments of metal which can be spun and woven on normal textile machinery. These metallic fibers possess the properties of the metal from which they are formed. Multicomponent metallic fibers are more commonly used in textiles and are usually made from flat aluminum filaments surrounded with or bonded between clear layers of polyester, cellophane, or cellulose ester or from polyester film which has been metallized through vacuum deposition of aluminum and then encapsulated in polyester. In general, the properties of these fibers resemble the properties of the plastic film used to form the multicomponent fiber. The fibers are generally weak and easily stretched but can be used for decorative purposes and for applications where electrical conductivity and heat resistance are important. Trade names for metallic fibers include Brunsmet and Lurex. 

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