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What is spandex
- Sep 05, 2018 -

Spandex is an abbreviation for polyurethane fiber and is an elastic fiber. Spandex is generally composed of a plurality of filaments, generally 10D/root. Currently, there are 15D/root or even 20D/root. The less the theoretical number, the better the uniformity of the strip, and the less chance of overlapping forms. The DMAC of the spinning solution is harmful to the liver of the human body. Generally, the 10D/root contains 0.5 mg/kg, and the 15D/root contains 0.7 mg/kg, which exceeds the standard. When producing Spandex, special attention should be paid to the winding tension, the number of cylinders, the breaking strength, the elongation at break, the degree of forming, the amount of oil adhered, the elastic recovery rate, etc. These problems directly affect the weaving, especially in knitting production. Single-sided cloth should pay more attention.


Basic characteristics

Spandex's translation of "Spandex" is a kind of elastic fiber, the scientific name Polyurethane, abbreviated (PU). It is called "Spandex" in mainland China. It is highly elastic and can stretch 6 to 7 times. However, it can quickly return to its original state with the disappearance of tension. Its molecular structure is chain-like, soft and extensible. Polyurethane enhances its properties by being joined to hard segments. Elastic fibers are divided into two categories: one is a polyester chain; the other is a polyether chain. The polyester elastic fiber is strong in oxidation resistance and oil resistance; the polyether elastic fiber has mildew resistance and good anti-detergent.


Advantage editing

Spandex is excellent in elasticity. The strength is 2 to 3 times higher than the latex yarn, the linear density is finer, and it is more resistant to chemical degradation. Spandex is good in acid and alkali resistance, sweat resistance, seawater resistance, dry cleaning resistance and wear resistance.


Synthetic fiber editing

Chemical fiber refers to those fibers that have been chemically processed from natural or synthetic high polymers. They can be classified into two types: man-made fibers and synthetic fibers. There are two types of man-made fibers, namely man-made cellulose fibers (such as viscose fiber, rich and strong fibers, etc.) and artificial protein fibers (such as soybean fiber, peanut fiber, etc.), while the synthetic fiber camp is relatively large, with polyester fiber (ie polyester). ), polyamide fiber (nylon 6, nylon 66, etc.), polyacrylonitrile fiber (acrylic fiber), polyvinyl formal fiber (Vinyl), polypropylene fiber (polypropylene), polyvinyl chloride fiber (chlorinated fiber), polyamino Formate fiber (spandex). The composition contains more than 85% of the polyurethane. The trade names are Lycra (United States, United Kingdom, United Kingdom, Netherlands, Canada, Brazil), Neolon (Neolon, Japan), Doralan (Dorlastan, Germany). Wait. First, it was successfully researched by Bayer in Germany in 1937. DuPont started industrial production in 1959 and has now sold its spandex industry to the Koch Industries Group, with a total capacity of about 100,000 tons. The global spandex production capacity is about 600,000 tons, and South Korea Hyosung's spandex production capacity is close to 120,000 tons, making it the world's number one. The first spandex company in China was the Yantai Spandex Factory, which began production in 1989. China's current production capacity is about 350,000 tons, making it the world's largest producer of spandex.


There are two varieties of spandex, one is an inlaid copolymer of aromatic diisocyanate and a polyester segment containing hydroxyl groups (referred to as polyester spandex), and the other is inlaid with aromatic diisocyanate and polyether segment containing hydroxyl group. Copolymer (referred to as polyether spandex). Spandex fibers and elastic polyolefin fibers and elastic composite fibers are collectively referred to as elastic fibers.