Olefin fiber is a synthetic fiber made from a polyolefin, such as polypropylene or polyethylene. It is used in wallpaper, carpeting, ropes, and vehicle interiors.
Olefin's advantages are its strength, colourfastness and comfort, its resistance to staining, mildew, abrasion, sunlight and its good bulk and cover.
Italy began production of olefin fibers in 1957. The chemist Giulio Natta successfully formulated olefin suitable for more textile applications. Both Natta and Karl Ziegler were later awarded the Nobel Prize for their work on transition metal catalysis of olefins to fiber, also known as Ziegler–Natta catalysis. U.S. production of olefin fibers began in 1960. Olefin fibers account for 16% of all manufactured fibers.
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, fire, 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.
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 for textile use.