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Polarized Light Digital Image GalleryFibersNatural fibers may be derived from many sources, including animals, vegetables, and minerals. The use of such fibers extends back beyond recorded history, archaeological evidence indicating that wool and flax had begun being woven into fabrics by the sixth century BC. Man-made fibers, however, which are fibers chemically and structurally altered to an appreciable extent during their production, were not developed until after the Industrial Revolution. The earliest of these fibers, including rayon and acetate, were comprised of the same cellulose polymers found in many natural fibers, though in a drastically modified form. Later man-made fibers, such as nylon and polypropylene, were created through purely artificial means and came to be classed in a separate category of fibers known as synthetics. Acetate Fibers - Manufactured from a renewable resource, acetate fiber is fashioned from the cellulose of softwood trees that is exposed to acetic acid and acetic anhydride before it is undergoes a partial hydrolysis to form a substance that can be easily dissolved in acetone. The solution formed by this process is passed through the small openings of a spinneret to form fibers, which are transferred into a chamber where they are exposed to warm air. The acetone readily evaporates in this environment, leaving behind the cellulose acetate fibers, which are wound on reels for later use in a wide range of products, such as ties, sweaters, lingerie, and bathing suits. Bombyx mori Reeled Silk Fiber - The larvae of several moth species belonging to the genus Bombyx produce the vast majority of commercial silk, and the most celebrated of these is the Bombyx mori, which creates the finest fiber. This common silkworm primarily feeds upon the leaves of the mulberry tree and has been so altered by its long history of domestication that it can no longer survive in the wild. The silk it produces is notorious for its whiteness and consistent level of high quality. Cotton Fibers - Cotton fiber is utilized to produce a seemingly boundless range of products and commodities. It has, however, historically been most popular as a material for clothing and other textiles due to its softness, absorbency, strength, and dyeability, as well as the ease with which it may be cared for. More recently, many of these same qualities have been responsible for cotton’s introduction into such products as paper, cardboard, medical supplies, plastics, and tire cord. Cuprammonium Rayon Fibers - Cuprammonium rayon, which is the variety that most closely resembles silk, was invented in 1890. The fiber is made through a process that involves dissolving the cellulose from wood pulp or cotton linters in a solution of copper oxide and ammonia, and then forcing the substance through a spinneret so that it is extruded in filaments that undergo stretch spinning. The result is a lustrous, very fine yarn that can be utilized to create sheer, lightweight fabrics with superior draping qualities, as well as hosiery. Flax Fibers - Linen made from high quality flax fibers is a remarkable material, which has been appreciated by many civilizations throughout history, including the ancient Egyptians who used it, among other things, to wrap mummies. Beautiful to behold due to its smoothness and lustrous sheen, the popular textile is also highly practical because it is absorbent, strong, durable, and resistant to microbial activity. Linen possesses exceptional heat conducting capabilities as well, which helps keep people who wear it as clothing cool during warm summers. Hemp Fibers - The most useful and valuable hemp fiber is derived from the plant scientifically described as Cannabis sativa. Cloth made from the fiber of this plant is extremely strong, durable, and resistant to mildew. It is also cheaper to produce than cotton cloth, and crops of Cannabis plants grow well without herbicides, fungicides, or pesticides. Due to its many advantages over other natural fibers, hemp has been utilized to create a wide variety of products over the course of history, including clothing, paper, rope, and netting. Kenaf Bast Fiber - The stems of kenaf plants are comprised of two different fibers, both of which are exploited commercially. An inner fiber, commonly referred to as the core, is woody, exhibiting coarseness and other properties similar to the fibers of hardwood trees. This material is heavily utilized in a wide array of paper products, as well as in particleboard. The fiber described as bast, however, is much softer and more flexible than the core it surrounds, making it a better-suited and more popular choice for many textiles and cordages. Milkweed Fibers - The fiber of milkweeds, which is often described as floss or silk, is stored in seedpods, which naturally dry and crack open in the autumn, releasing the seeds into the wind for dispersal. Composed of tiny cellulose tubes filled with air, the fibers are unusually buoyant and were utilized during World War II to fill life jackets when kapok fiber became scarce. After the war, milkweed fiber usage tapered off, but over the last twenty years several companies have begun to reexamine the possibilities offered by the soft, lustrous material. Nylon Fibers - Nylons are composed of polymers containing repeated amide groups called polyamides that have a high molecular weight. When produced as fibers, nylons are elastic and strong. If these fibers are stretched into fine filaments, they become lustrous and can be spun into a material that is similar to silk. It is in this form, which has been commonly utilized in hosiery since the 1940s, that nylons are perhaps most familiar. In addition to their luxurious appearance, fine nylon materials have a low moisture absorbency and are resistant to mold, mildew, chemicals, and abrasion. Orlon Fibers - Early in its development, Orlon was a problematic fiber to spin or dye. However, the ongoing work of DuPont eventually resulted in a material that was a tremendous commercial success, though it has been replaced in recent years by newer synthetic fibers in many applications. Warm and soft, Orlon was a longtime favorite in clothing and its resistance to degradation from sunlight and atmospheric gases also made it well-suited for outdoor items, such as beach umbrellas and awnings. Polybenzimidazole Fibers - Polybenzimidazole (PBI) is a high performance polymer fiber that was discovered in the 1950s and developed by the Celanese Corporation over the next decade. NASA became interested in the unique qualities of the fiber after a fire erupted aboard an Apollo spaceship in 1967, spurring them to combine forces with Celanese in the development of a line of PBI textiles. PBI fibers first became commercially available in 1983 and since that time the fibers have found wide usage in a number of areas. Polypropylene Fibers - Due to its many favorable characteristics and production improvements, polypropylene availability and use has increased significantly over the last few decades, a trend that is likely to continue in the upcoming years. Strong, colorfast, quick drying, stain resistant, and thermally bondable, as well as durable against chemicals, mildew, and various weather conditions, polypropylene is, indeed, well suited for a wide range of applications. Furthermore, the substance has a very low specific gravity that enables it to float when it is in fiber form. Ramie Fiber - Native to Southeast Asia, the plant from which ramie fiber, also known as China grass, is derived is a member of the nettle family scientifically described as Boehmeria nivea. The extraction of fibers from the plant can be a somewhat complex and expensive process because several steps are required in order to successfully separate the filaments from surrounding gums and resins. The spinning and weaving of ramie can also be an intricate and difficult endeavor due to the characteristic brittleness and relative inflexibility of the fibers. Saran Fiber - Saran was initially utilized by the United States military, who sprayed it on fighter planes and other equipment as a protectant against the elements. Carmakers also utilized an early version of the material in upholstery to make it more resilient. Later, after scientists were able to eliminate its greenish hue and foul scent, Saran was found to be an ideal material for food packaging. By 1949, Saran Wrap was introduced by Dow as the first commercial cling wrap, and only a few years later it became a common household product used to securely wrap countless sandwiches and cover innumerable leftover items. Short Asbestos Fibers - Utilized since antiquity, asbestos is primarily valued for its fire resistance, but is also appreciated for its strength, low electrical conductivity, and elasticity. The fiber was not commercially produced on a massive scale, however, until the latter part of the nineteenth century when mining operations began in Italy and then Canada. For about 100 years, asbestos was widely utilized for a variety of applications. The longer fibers that were obtained were commonly spun into yarn used in break linings and insulation, while short asbestos fibers were generally included in paper products and cement-based building materials. Silver Cotton Fibers - Individual cotton fibers naturally flatten and twist when they are dried. This characteristic makes it easier for cotton to be spun than most other materials because the fibers more readily interlock into threads. It also typically results in a stronger thread than many other fibers. Fabrics made from cotton, therefore, are extremely durable, as well as inexpensive to buy since there is such an abundance of cotton crops. Silver Ramie Fibers - Comprised of cells that are exceptionally long, ramie is one of the strongest vegetable fibers in the world. Because of this, the material is frequently utilized in items that require exceptional strength and durability, such as rope, industrial sewing thread, and fishing nets. Ramie is also very absorbent and a natural lustrous white in color, making it highly accepting of a wide variety of dyes. Spectra 1000 Fiber - An extended-chain polyethylene fiber, Spectra 1000 boasts one of the highest strength to weight ratios of any fiber made by man. In fact, when measured pound-for-pound, the exceptional fiber, which is more durable than polyester, is 10 times stronger than steel. Spectra 1000 is also light enough to float, as well as resistant to water, ultraviolet radiation, chemicals, flex fatigue, and abrasion. Moreover, the fiber’s low dielectric constant renders it practically invisible to radar systems. Tencel Fibers - Though the fiber is manmade, Tencel is derived from the wood pulp of trees grown in managed forests and is completely biodegradable. The production of the fiber involves a “closed loop” spinning process, in which the non-toxic solvent is continuously recycled and energy and water are conserved. Twisted or spun into yarns, Tencel can easily be utilized to knit or weave fabrics that are strong, absorbent, and comfortable. Thrown Raw Silk Fibers - Silk that retains its natural sericin is called raw silk. The gelatinous nitrogenous protein is frequently left in place during much of the processing of silk fiber because it provides a certain amount of protection to the delicate strands. However, the sericin is usually removed in the yarn or fabric stage by subjecting the material to boiling water and soap. The result is a very soft, lustrous, semitransparent silk that may be reduced in weight by as much as 30 percent. Wild Silk Fibers - A demand for organic and environmentally friendly products has inspired some entrepreneurs to concentrate on the production of what is often termed wild silk or tussah. In the production of these materials, the silkworms are allowed to live a more natural existence, feeding on all different kinds of trees and carrying out their entire life cycle. The fibers they produce fluctuate in color due to their varied diet, but are often brownish and may be difficult to bleach. Contributing Authors John D. Griffin, Shannon H. Neaves, Nathan S. Claxton, and Michael W. Davidson - National High Magnetic Field Laboratory, 1800 East Paul Dirac Dr., The Florida State University, Tallahassee, Florida, 32310. Questions or comments? Send us an email.© 1998-2022 by Michael W. Davidson and The Florida State University. All Rights Reserved. No images, graphics, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.
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