Wool
In addition to wool’s outstanding performance as a cold weather fabric, its fire resistant properties make it a desirable material for carpets and upholstery.
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For residents of northern regions, autumn heralds annual changeover from cotton T-shirts to wool sweaters. Although wool is most often associated with sheep, it can include cashmere and mohair from goats, angora from rabbits and even fibers derived from the coats of camels, alpacas, and muskoxen.
Although wool is often thought of as a cold weather fabric, its insulating ability has advantages in warm weather as well. While wool fibers are rather bulky compared to other fibers, wool creates a layer of air between the garment and a person’s skin. In cold weather, this keeps warmth in, and hot weather wool keeps hot air off the skin. Wool fibers are hollow and hydrophilic, which means they can absorb up to 30 percent of their weight in moisture without feeling damp. This property makes wool a vastly preferred material over cotton for outdoor activities in cool temperatures since cotton holds moisture close to the skin; with cold, wet cotton clothing, the body can rapidly become chilled as body heat is leached away to try to evaporate the water.
Wool proteins, which also have an alpha helix structure, in other words, a natural crimp, which explains wool’s tendency to stretch. Fine soft wools such as merino wool used for high-quality clothing contain many crimps per inch. At the other end of the spectrum, fibers that have just a few crimps per inch are scratchier and lower quality; these fibers may be used to make outerwear or rugs.
One of the unique advantages of wool is its resistance to fire. It often self-extinguishes when the source of the original flame is removed. As a result, wool is highly desirable for carpets and upholstery in trains and airplanes and for clothing worn by fire fighters.
More information about wool is available at http://www.sheep101.info/wool.html