Natural fibers animal

Fibers for commercial and domestic use are broadly classified as natural or synthetic. The natural fibers are vegetable, animal, or mineral ia origin. Vegetable fibers, as the name implies, are derived from plants. The principal chemical component ia plants is cellulose, and therefore they are also referred to as ceUulosic fibers. The fibers are usually bound by a natural phenoHc polymer, lignin, which also is frequentiy present ia the cell wall of the fiber thus vegetable fibers are also often referred to as lignocellulosic fibers, except for cotton which does not contain lignin. 

In general, natural fibers are subdivided as to their origin, coming from plants, animals, or minerals (Fig. 2). Plant fibers usually are used as reinforcement in plastics. The plant fibers may be hairs, fiber sheafs of dicotylic plants, or vessel sheafs of monocotylic plants (bast and hard fibers). 

Fibers that come from natural sources, such as minerals, animals, and plants, are classified as natural fibers [5,6],... 

The first fibers used by humans were probably those that occur naturally as tissues or excretions of either vegetables or animals (see Table 87). At much later times, after metals had been discovered, humans also learned to manufacture - from some of the ductile metals, mainly gold, silver, and their alloys - thin filaments (not fibers, however), which have since been used to decorate textile fabrics. It was only during the twentieth century, after synthetic plastics were discovered, that it became possible to make artificial human made fibers. The great majority of the natural fibers, such as cotton and wool, occur as staple fibers, short fibers whose length is measured in centimeters. Silk is different from all other natural fibers in that it occurs as extremely long and continuous filaments several hundred meters long. 

If the most-probable orientation of the structural entities is no longer parallel to the fiber axis, we may observe a clearly inclined streak. Such orientations are frequently observed in herbal and animal natural fibers [45,260,261], If the split nature of the orientation distribution is clearly detected, the streak method can be applied or adapted. 

Most plant and animal materials contain natural fibers that have been concerted into useful fibers for thousands of years including ropes, building materials, brushes, textiles, and brushes (Table 18.6). Animal protein fibers such as wool and silk are no longer competitive with synthetic fibers with respect to cost but are still often utilized in the production of high-end rugs. Some of these rugs are hundreds of years old yet retaining their color and physical properties. 

There has always been an abundance of natural fibers and elastomers, but few plastics. Of course, early humans employed a crude plastic art in tanning the protein in animal skins to make leather and in heat-formed tortoise shells. They also used naturally occurring tars as caulking materials and extracted shellac from the excrement of small coccid insects Coccus laced). 

Fibers exist as natural, or synthetic, hydrophilic, hydrophobic, nonionic, and ionic. Natural fibers hnvc complex chemical structures with a multitude of possible points of attraction for a dyestuff and are difficult io characterize because of the structure being strongly influenced by regional, climatic variations and the species of plant or animal. Dyeing of natural fibers is therefore much more complex than dyeing synthetic fibers where structures can be characterized and the availability of points of attraction can be deliberately engineered into the fiher s molecular chain. The various types of liher arc summarized in Tahle I. The fiber type dictates the type of dye needed. 

Among the natural fibers are cellulose, the primary structural component of plants and bacterial cell walls animal fibers such as wool and silk and biochemical fibers. Plant fibers are composed of cellulose (see Figure 1), lignin (see Figure 2), or similar compounds animal fibers are composed of protein (see Figure 3). 

As will be shown, it should be theoretically possible to make any of the common manufactured fibers in bicomponent forms. However, acrylics have received the most attention for quite good reasons. Their general characteristics have tended to make them competitive with wool. This means that they should be processible on machinery developed for handling wool, as well as capable of being accepted into markets previously dominated by an animal hair fiber. It follows that because the natural fiber possesses crimp which produces the cohesion that determines its behavior in processing and in part its appearance and hand in usage, a similar crimp was desired for acrylics. 

In this survey, commercially important textile fibers are grouped by their origin. First there are the natural fibers from plant sources, cotton and flax, and those from animal sources, wool and silk. A second group consists of those fibers that are regenerated or chemically... 

All natural fibers derived from animals have a proteinaceous constituent collagen, keratin, or fibroin. Fibroin is the fibrous constituent in silk fiber (see below). The basic building block of a protein is an amino add which has the following formula ... 

The world textile industry is one of the largest consumers of dyestuffs. An understanding of the chemistry of textile fibers is necessary to select an appropriate dye from each of the several dye classes so that the textile product requirements for proper shade, fastness, and economics are achieved. The properties of some of the more commercially important natural and synthetic fibers are briefly discussed in this section. The natural fibers may be from plant sources (such as cotton and flax), animal sources (such as wool and silk), or chemically modified natural materials (such as rayon and acetate fibers). The synthetic fibers include nylon, polyester, acrylics, polyolefins, and spindex. The various types of fiber along with the type of dye needed are summarized in Table 8.2. 

Natural fibers may be of animal, vegetable, or mineral origin. Although the annual production of vegetable fibers outweighs that of animal or mineral fibers, all have long been useful to humans. 

The process by which the atoms of one or more substances are rearranged to form different substances is called a chemical reaction. A chemical reaction is another name for a chemical change, which you read about in Chapter 3. Chemical reactions affect every part of your life. They break down your food, producing the energy you need to live. They produce natural fibers such as cotton and wool in the bodies of plants and animals. In factories, they produce synthetic fibers such as nylon and polyesters. Chemical reactions in the engines of cars and buses provide the energy to power the vehicles. 

Numerous fibrous products are used as fillers in plastics materials. Fibers are generally divided into natural and man-made fibers. The natural fibers belong to three groups vegetable, animal, and mineral fibers. Natural mineral fibers were... 

Although natural fibers are usually classified according to their origin as animal or vegetable, chemists generally think of them from the viewpoint of their chemical nature as protein or cellulosic. The mineral kingdom also produces an important fiber—asbestos —which has had Incited use in the textile field because of processing difficulties. 

Humans first relied on natural polymers for clothing, wrapping themselves in animal skins and furs. Later, they learned to spin natural fibers into thread and to weave the thread into cloth. Today, much of our clothing is made of synthetic polymers (e.g., nylon, polyester, polyacrylonitrile). Many people prefer clothing made of natural polymers (e.g., cotton, wool, silk), but it has been estimated that if synthetic polymers were not available, all the arable land in the United States would have to be used for the production of cotton and wool for clothing. 

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