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| Classification chart of textile fibers. |
Fibers are classified by their chemical origin, falling into two groups or families: natural fibers and manufactured fibers. Manufactured fibers are also referred to as manmade or synthetic fibers.
Textile fibers can be classified in following main category:
- Natural fibers.
- Man-made fibers.
NATURAL FIBERS
Textile fibers directly obtained from nature are called natural fibers. These fibers can not be produced by any type of chemical process. Natural fibers are those that occur in fiber form in nature. Traditionally, natural fiber sources are broken down into animal, plant, or mineral. Fibers from plant or vegetable sources are more properly referred to as cellulose-based and can be further classified by plant source. They may be separated from the plant stalk, stem, leaf, or seed. Fibers from animal sources are more properly known as protein-based fibers. They are harvested from an animal or removed from a cocoon or web. Mineral fibers are those that are mined from the earth. Except for silk, all natural cellulose- and protein-based fibers are obtained in short lengths and are called staple fibers. Silk is a continuous filament fiber.
Natural fibers further can be classified in two categories according to its source of generation.
A-) Cellulose based/Vegetable fibers: cotton, linen, jute, hemp, banana, kapok, kenaf, ramie, raffia, sisal, coir etc.
B-) Animal fibers: wool, silk spider silk, rabbit hairs, camel hairs, goat hairs, yak.
C-) Mineral based fibers: asbestos etc.
A-) Cellulose Based Fibers
Cellulose based fibers consist of bast, leaf, and seed-hair fibers. Bast fibers come from the stem of the plant and include flax, hemp, jute, and ramie. Leaf fibers are stripped from the leaves of the plant and include manila and sisal. Seed-hair fibers are collected from seeds or seed cases and include cotton and kapok.
1-) Cotton
Cotton, obtained from the cotton seed, is the best-known and most-used natural cellulosic fiber.
2-) Flax
Flax is the bast fiber of the flax plant, used to make linen fabric. The plants are cultivated and grown in such a way as to produce long, thin stems. The plant is pulled from the ground for processing. The non-fibrous material in the stem is rotted away in a process called retting. Once retting is complete, the fibrous mass is rinsed and dried. The fiber is separated from the woody portion of the decomposed material by breaking and scutching (scraping). Hackling refers to combing the scutched fibers to separate the long and short fibers. The fiber is then spun, and S-twist is inserted, to produce linen thread.
3-) Hemp
Hemp is a coarse, durable bast fiber from the plant Cannabis sativa. It is processed into a usable fiber in the same way as flax. It is used primarily for industrial and commercial textiles, especially cords, twine, and rope.
4-) Jute
Jute is a bast fiber from the stem of plants in the genus Corchorus, processed in the same way as flax. It widely used for industrial end uses such as sacking, burlap, twine, and backing for tufted carpets.
5-) Kapok
Kapok is from the seed pods of the Java kapok tree (Ceiba pentandra). The seed pod is similar to the cotton boll; however, the dried fibers are easily shaken off the seed. A buoyant fiber, kapok is used primarily in life jackets, as special stuffing for pillows, and in some mattresses. It is not spun into yarn.
6-) Manila
Manila is from the leaf stalks of the abacá plant (Musa textilis). The fibers are separated from the fleshy part of the leaf stalk. Manila is generally used in rope and cordage.
7-) Ramie
Ramie is a bast fiber from the stalk of the ramie plant (Boehmeria nivea), also known as China grass. The plant is a perennial shrub that can be cut several times a year once mature. The cut plant’s stalks are peeled or retted to remove the outer woody covering, revealing the fine fibers underneath. Degumming removes pectins and waxes, followed by bleaching, neutralizing, washing, and drying. The fiber is similar to flax, but more brittle. Ramie can be spun alone or with other fibers, especially cotton.
8-) Sisal
Sisal is from the leaves of plant Agave sisalana. The leaves are cut when the plant is about four years old, and the fibers are separated from the fleshy part of the leaf. Sisal has industrial uses, most commonly as a rug or carpet backing.
B-) Protein-Based Fibers
Protein-based fibers are from animal sources, most commonly the hair of the animal. Animal-hair fibers are long-staple fibers, ranging in length from 6 to 25 cm or more. Silk is a natural protein fiber extruded by the silk worm. With a length of over 500 yards, it is classified as a filament fiber.
1-) Wool
Wool is a fine hair fiber from sheep. In labeling, the term wool also may be used to identify fibers from other fleece animals, such as the Angora goat, Cashmere goat, camel, alpaca, llama, and vicuña. Sheep-wool fiber can be sheared from the living animal or pulled from the hide after slaughtering. Sheared or clipped wool is superior to pulled wool. Sheep normally are sheared only once a year. Lamb’s wool is wool from sheep under 8 months of age. Virgin wool (or new wool) comes from the first shearing of the animal and is most highly prized. (The term virgin wool is also used to mean wool that has never previously been processed.)
2-) Silk
Silk is a natural protein secreted by the larvae of several moth species. The larvae use the filaments to construct a cocoon, from which the silk is extracted. Twin filaments of the protein fibroin are secreted and bound together in a single strand with the protein gum sericin. During processing, the sericin is removed, leaving the fibroin protein. Cultivated or cultured silk is produced in very controlled conditions of environment and diet. Tussah or wild silk is harvested from natural sources.
3-) Alpaca
Alpaca is the long, fine hair fiber from the alpaca, which is a relative of the camel native to South America. It is shorn from the animal once every two years. The soft, fine undercoat is used in textiles.
4-) Angora (Ankara)
Angora is the long, fine hair fiber from the Ankara (Capital of Turkiye) rabbit. It is not to be confused with the hair fiber of the Ankara goat, the source of mohair. Ankara rabbits are raised domestically. The fur is combed and clipped from the rabbit every three months.
5-) Camel
Camel hair comes from the Bactrian camel. The fiber is shed, and about 2.7 kilograms is produced per camel. The underhairs are used in textiles, and the coarse outer guard hairs are used in paint brushes and other non-apparel uses.
6-) Cashmere
Cashmere is the soft hair fiber from the cashmere (kashmir) goat. The fiber is harvested by combing the animal. A single goat produces only about 114 grams of fiber a year. Cashmere is considered a luxury fiber.
7-) Llama
Llama hair fibers are shorn from the animal once a year. They are similar to alpaca fibers, but weaker.
8-) Mohair
Mohair is the long, straight, fine hair fiber from the Ankara goat. The fiber is usually sheared from the animal twice a year.
9-) Vicuna
Vicuña is the hair fiber from a small non-domesticated llama-like animal. The animal lives at elevations above 16,000 feet in South America and has been listed as endangered since 1969. Vicuña is the softest of the fleece fibers.
C-) Mineral Based Fibers
Mineral-based fibers are mined from the earth. Asbestos is by far the most common mineral-based fiber. Asbestos is not used today for general apparel or home furnishings, because exposure to asbestos poses serious health risks. However, it is still used in some heavy industrial and aerospace applications, because it is completely nonflammable.
MAN-MADE FIBRES
Textile fibers produced by human through one or more types of chemical process are called man-made or synthetic fibers. These fibers are produced in laboratory and in industrial manufacturing units. These fibers are produce by polymerization of a monomers of chemical compounds. Few common examples are polyester, nylon, acrylic, polypropylene, elastane, poly vinyl aetate, poly vinyl alcohol, poly vinyl chloride, polythene, poly urethene etc.
Manmade fibers, such as nylon, polyester, and rayon, are produced by chemical reactions controlled by people, rather than occurring naturally. The term synthetic fibers is often used to designate manmade fibers; however, to many people, this term has a negative connotation, meaning inauthentic, artificial, or fake. Classified manmade or manufactured fibers by generic names. Currently, recognizing 26 generic groups of manmade fibers. Three conditions must be met before a new generic group is established:
- The chemical composition must be radically different from those on the list, and that chemical constitution must produce significantly different physical properties.
- A new proposed classification must have importance to the majority of consumers and not just to a small group of professionals.
- The fiber must be in active commercial development. Manmade fibers are identified as being made from a natural polymer base, made from a synthetic polymer base, or mineral- or specialty-based.
A-) Natural-Polymer-Based Fibers
These fibers can neither diretly found from nature nor can be produce by using chemical. These fibers are re-generated from natural material using some chemical process. Monomers are obtained by treating natural material with chemicals. Common examples are rayon, modal, lyocell etc.
Regenerated natural-polymer-based fibers include cellulose-based, protein-based, alginate, rubber, and starch fibers. Cellulose-based fibers include rayon, acetate, triacetate, and lyocell.
1-) Rayon
Rayon is a manufactured fiber composed of regenerated cellulose. Regenerated cellulose is a fiber in which substituents have replaced not more than 15 % of the hydrogens of the hydroxyl groups of the original cellulosic material. Common sources of rayon raw cellulose material are cotton, wood pulp, various grasses, and, recently, bamboo. Rayon is produced by three methods: the viscose, cuprammonium, and solvent-spun (lyocell) processes.
a-) Viscose
Viscose rayon is produced by dissolving cellulose xanthate into sodium hydroxide. The xanthate solution is extruded into an acid bath, where the pure cellulose is regenerated and coagulated into filament form.
b-) Cuprammonium rayon
Cuprammonium rayon fibers are formed by precipitation of cellulose dissolved in a solution of copper oxide and ammonia.
c-) Lyocell (Solvent spun rayon)
Solvent-spun rayon is formed by dissolving wood pulp in amine oxide. This newer process is considered more environmentally friendly then the other methods, because 99 % of the solvent is reclaimed. The patents on this process are owned by Lenzing, and the fiber generic name is lyocell.
2-) Acetate
Acetate fibers are manufactured fibers in which the fiber-forming substance is cellulose acetate. Where at least 92 % of the hydroxyl groups are acetylated, the term triacetate may be used as a generic description of the fiber.
B-) Synthetic-Polymer-Based Fibers
Synthetic-polymer-based fibers are those made from chemical polymers not found in nature. These fibers are mainly insoluble and are not chemically reactive. The most common synthetic-polymer-based fibers are acrylics, aramids, modacrylics, nylon, olefins, polyester, and spandex.
1-) Nylon
Nylon is a manufactured fiber formed from a long-chain synthetic polyamide in which at least 85% of the amide linkages are attached directly to two aromatic rings. Nylon is melt-spun and is produced in a variety of cross-sectional shapes. Nylon comes in several types, produced by different reaction processes. The most common types are nylon 6 and nylon 6,6. Nylon is used in almost every textile application.
2-) Acrylic
Acrylic is a manufactured fiber formed from any long-chain synthetic polymer composed of at least 85% acrylonitrile units by weight. The goal in developing acrylic was to have a fiber to compete with wool in staple form and silk in filament form. Currently, only staple acrylic fibers are produced. The specific gravity is low (1.17), resulting in a soft but not bulky hand. Acrylics also have excellent resistance to sunlight; long exposures do not affect their strength or color. The most common uses for acrylics today are socks, knit sweaters, tenting, awnings, and loungewear.
3-) Modacylic
Modacrylic is a manufactured fiber formed from any long-chain synthetic polymer consisting of less than 85% but at least 35% acrylonitrile units (except fibers qualifying as rubber or anidex, an elastomeric fiber like spandex). Like acrylics, modacrylics have excellent resistence to sunlight. Modacrylics are by their chemical nature flame retardant, being hard to ignite and self-extinguishing.
4-) Aramid
Aramid is a manufactured fiber formed from a long-chain synthetic polyamide in which at least 85 % of the amide linkages are attached directly to two aromatic rings. The spinning system is a solvent process, of which there are variations. Aramid fibers offer a high level of performance. The best-known aramids are Nomex and Kevlar. Nomex is similar to nylon in strength, but is flame retardant. Kevlar is extremely strong. Both fibers are coarser than other synthetics and are extremely hard to dye.
5-) Olefin
Olefin is a manufactured fiber formed from any long-chain synthetic polymer consisting of at least 85 % ethylene, propylene, or other olefin units (except amorphous [noncrystalline] polyolefins qualifying as rubber). Olefins consist only of carbon and hydrogen atoms, and their cross-sectional shape can vary. The two major olefins are polyethylene and polypropylene, which have good strength (with polypropylene the stronger). Olefins are extremely sensitive to heat. They can shrink excessively at temperatures as low as 100 °C, which limits their use with other fibers that are processed in dyeing and finishing at temperatures above 100 °C. Also, fabrics made of olefin are very difficult to iron. Olefins have essentially no moisture regain or absorption, which is a benefit for rainwear uses, but makes the products uncomfortable to wear in humid conditions. Olefins are important to the industrial markets, with applications in carpets, carpet backing, fiber bale coverings, bags, agricultural end uses, and ropes, among many others.
6-) Polyester
Polyester is a manufactured fiber formed from any long-chain synthetic polymer consisting of at least 85 % the ester of a substituted aromatic carboxylic acid, including (but not limited to) substituted terephthalate units and para-substituted hydroxybenzoate units. Polyester comes in numerous types, depending on the chemistry used in production. All polyesters are inert. They offer a wide range of performance features, but because they are inert, they are not easily modified. Polyesters are oleophilic (having a strong affinity for oils) and therefore must be treated with a soil-release chemistry to prevent soiling and body-odor retention. Along with nylon, polyester is important in apparel, home, commercial, and industrial markets.
7-) Rubber
Rubber fibers are manufactured fibers formed from natural or synthetic rubber. Charles Goodyear discovered the process for vulcanizing rubber, which allowed the fiber to be extruded into shapes, including a textile fiber. Natural rubber from rubber trees and synthetic rubber are classified the same, and no distinction is made on care labels.
8-) Spandex
Spandex fibers are manufactured fibers formed from a long-chain synthetic polymer consisting of at least 85 % segmented polyurethane. Spandex fibers are elastomeric fibers, which are stretchy and rubber-like substances. They have extremely high elongation, at least 200% and in some cases up to 800 %. Rubber and spandex are the best-known elastomeric fibers. Spandex is a segmented block polymer and has several cross-sectional shapes, of which the most common is a dog bone shape. The extrusion process results in some fusing of adjacent filaments to produce a coalesced filament yarn. Spandex fibers are very weak; however, the high degree of stretch allows for uses where the lack of strength is overcome. In apparel products, spandex is almost always used only in small amounts with other fibers to provide a desired degree of stretch.
C-) Manmade Mineral-Based and Specialty Fibers
Manmade mineral-based and specialty fibers include special-use fibers such as glass fibers and metallic fibers.
1-) Fiberglass
Fiberglass is a generic term used to identify manufactured fibers formed from molten silica glass; the name Fiber-glas is a registered trademark. Glass fibers have high strength but very low elongation. Their tactile properties are unpleasant, because the cut ends of the glass fibers cause tiny cuts in the skin. These properties prevent fiberglass from being used for apparel. However, fiberglass has very important industrial applications and is used to some extent for home-textile products, such as draperies.
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