Olefin fiber

Olefin fiber is a synthetic fiber made from alkenes. It is used in the manufacture of various textiles as well as clothing, upholstery, wallpaper, ropes, and vehicle interiors. Olefin is also referred to as polypropylene, polyethylene, or polyolefin. Olefin's advantages are its strength, colorfastness, comfort, stain, mildew, abrasion and sunlight resistance, and good bulk and cover.

History
Italy began production of olefin fibers in 1957. The chemist Giulio Natta successfully formulated olefin suitable for more textile applications. U.S. production of olefin fibers began in 1960. Olefin fibers account for 16% of all manufactured fibers.

Major fiber properties
Olefin fibers have great bulk and cover while having low specific gravity. This means “warmth without the weight.” The fibers have low moisture absorption, but they can wick moisture and dry quickly. Olefin is abrasion, stain, sunlight, and chemical resistant. It does not dye well, but has the advantage of being colorfast. Since Olefin has a low melting point, textiles can be thermally bonded. The fibers have the lowest static of all manufactured fibers and a medium luster. One of the most important properties of olefin is its strength. It keeps its strength in wet or dry conditions and is very resilient. The fiber can be produced for strength of different properties.

Production method
The Federal Trade Commission's official definition of olefin fiber is “A manufactured fiber in which the fiber forming substance is any long-chain synthetic polymer composed of at least 85% by weight of ethylene, propylene, or other olefin units”

Polymerization of propylene and ethylene gases, controlled with special catalysts, creates olefin fibers. Dye is added directly to the polymer before melt spinning is applied. Additives, polymer variations and different process conditions can create a range of characteristics.

High pressure production, which uses ten tons per square inch, creates a film for molded materials. Low pressure production uses a low temperature with a catalyst and hydrocarbon solvent. This process is less expensive and produces a polyethylene polymer more suitable for textile use.

The polymer is then melted, spun into water, or air cooled. The fiber is drawn out to six times the spun length. Gel spinning is a new method in which a gel form of polyethylene polymers is used.

Physical
Olefin fibers can be multi- or monofilament and staple, tow or film yarns. The fibers are colorless and round in cross section. This cross section can be modified for different end uses. The physical characteristics are a waxy feel and colorless.

Chemical
There are two types of polymers that can be used in olefin fibers. The first, polyethylene, is a simple linear structure with repeating units. These fibers are used mainly for ropes, twines and utility fabrics.

The second type, polypropylene, is a three dimensional structure with a backbone of carbon atoms. Methyl groups protrude from this backbone. Stereospecific polymerization orders these methyl groups to the same spatial placement. This creates a crystalline polypropylene polymer. The fibers made with these polymers can be used in apparel, furnishing and industrial products.

Manufacturers
The first commercial producer of an olefin fiber in the United States was Hercules, Inc. (FiberVisions). In 1996, polyolefin was the world’s first and only Nobel Prize winning fiber. Other U.S. olefin fiber producers include Asota; American Fibers and Yarns Co; American Synthetic Fiber, LLC; Color-Fi; FiberVisions; Foss Manufacturing Co., LLC; Drake Extrusion; Filament Fiber Technology, Inc.; TenCate Geosynthetics; Universal Fiber Systems LLC.

Trademarks according to fabric use
Producer – Allied-Signal
 * A.C.E. – Tire cord, furniture webbing

Producer – DuPont
 * CoolMax – Warm-weather and action wear
 * Hollofil, Quallofil – Fiberfill and insulating fibers
 * Sontara – Spunlaced nonwoven fabrics
 * Thermostat – Cold-weather wear
 * Thermoloft - Fiberfill and insulating fibers
 * Tyvek - Used for house wraps to postal envelopes to clothing

Producer – Trevira
 * ESP – Apparel and furnishings
 * Celwet – Nonwovens
 * Comfort Fiber – Staple fiber for apparel uses
 * Loftguard – Staple fiber for industrial uses
 * Polar Guard
 * Lambda – Filament yarns with spun-yarn characteristics
 * Serene
 * Superba
 * Trevira HT – Marine and military uses; ropes, cordages
 * Trevira ProEarth – Recycled-content geotextiles
 * Trevira XPS - Carpeting
 * BTU – Cold-weather apparel

Uses

 * Apparel: Sports & active wear, socks, thermal underwear; lining fabrics.
 * Home Furnishing: Olefin can be used by itself or in blends for indoor and outdoor carpets and carpet tiles, carpet backing. The fiber can also be used in upholstery, draperies, wall coverings, slipcovers, and floor coverings.
 * Automotive: Olefin can be used for interior fabrics, sun visors, arm rests, door and side panels, trunks, parcel shelfs, and resin replacement as binder fibers,
 * Industrial: In an industrial setting, olefin creates carpets; ropes, geo-textiles that are in contact with the soil, filter fabrics, bagging, concrete reinforcement, and heat-sealable paper (e.g. tea- and coffee-bags).

Care procedures
Dry cleaning Olefin is not recommended, because many dry-cleaning solvents can swell the fibers. As Olefin dries quickly, line drying and low tumble drying with little or no heat is the recommended method of drying. Since Olefin is not absorbent, waterborne stains do not present a problem. However, oily stains are difficult to remove. Most such stains can be removed with lukewarm water and detergent, but bleach can also be used. Olefin fiber has a low melting point (around 225 to 335 °F, depending on the polymer's grade) so items should be ironed at a very low temperature, if at all. Items such as outdoor carpets and other fabrics can be hosed off. Olefin is easy to recycle.