Lycra spandex fiber

Use of 1,3 cycloaHphatic diamines in polyamides may be similarly limited by internal amide dehydration of the conformationaHy labile cis isomers to form a tetrahydropyrimidine (38) rather than high molecular weight polyamide. 1,3-Cyclohexanediamine is, however, a component of Spandex polyureas Du Pont uses the hydrogenation product of y -phenylenediamine [108-45-2] (24) captively to produce Lycra (see Fibers, elastomeric). 

Figure 4.8 cont.) (b) Specific stress-strain curves of Lycra (Spandex) and natural rubber fibers (Wilson, 1967,1968). 

Research and development in fluid jet technology led to its widespread use in film and web processing, mixers, reactors, and fiber processing. Applications to fibers alone includes Taslan bulked yams, jet piddlers, draw-jets, interlaced yams, bulk-crimped carpet fibers (BCF), and spunbonded products such as Reemay polyester, Typar polypropylene (PP), and Tyvek olefins. New fibers also were introduced Nomex aramid, especially suited for high-temperature applications Lycra spandex, an elastic textile yam Qiana nylon, with a silklike appearance and Kevlar aramid, used in products ranging from tires to bullet-resistant vests. 

One particular form of thermoplastic polyurethane elastomer is the elastic fiber known as Spandex. Several commercial materials of this type have been introduced, which include Lycra (Du Pont), Dorlastan (Bayer) Spanzelle (Courtaulds), and Vyrene (U.S. Rubber). Spandex fibers have higher modulus, tensile strength, and resistance to oxidation, and are able to produce finer deniers than natural rubber. They have enabled lighter-weight garments to be produced. Staple fiber blends of Spandex fiber with non-elastic fibers have also been introduced. 

A local company, Griffin Manufacturing, produces a line of jog bras. These items are made from mixed fiber fabric that includes between 10 and 15% Lycra spandex blended with cotton and polyester. The complexity of the product contributes to the production of a large volume of landfilled remnants. The company landfilled an estimate of at least six tons of this specific material per month in addition to other fabric types. That volume had doubled in the last few years and was expected to grow. 

In the early 1960s when spandex production started in earnest there were four manufacturers E.I. DuPont deNemours (Lycra spandex), Monsanto, Globe Manufacturing (Glospan Cleerspan spandex), and American Cyanamid. At that time DuPont controlled approximately 80% of the market. Since then, Monsanto and Cyanamid have ceased manufacturing and DuPont expanded international production, but eventually sold its fiber business to Invista. Additional competitors have appeared on both the national and international scene. In the USA Lycra spandex is the best known of the competitors. 

A garment manufacturer, Griffin Manufacturing Co., Fall River, Massachusetts, a partner in this research project, produces a jogging bra which is constructed of two layers of knitted fabric. The blue outer fabric contains 43% cotton, 43% polyester and 14% Lycra spandex. The white inner lining contains 90% CoolMax and 10% Lycra spandex. CoolMax is a DuPont trademark for fabric containing DuPont tetra-channel Dacron polyester fiber. - All these materials are characterized in another section of this report. 

Fiber content 43% cotton, 43% polyester, 14% Lycra spandex ... 

Lycra, spandex, and tactel are fibers that stretch easily and are also tight-fitting. They are used to make active wear, bras, and swimsuits. 

We all use spandex, that extremely stretchable fiber known as elastane in Europe or called Lycra if manufactured by DuPont It provides the "stretch" in panty hose and other undergarments, swimsuits, jeans, cycling shorts, tights, and many other articles of clothing. 

In much the same way, natural polymeric fibers like wool, cotton, silk, etc., are often touted as superior to anything that is man-made or synthetic. But is this fair There is no doubt that natural fibers have a unique set of properties that have withstood the test of time (e.g., it is difficult, but not impossible, to match silk s feel or cotton s ability to breathe ). On the other hand, consider Lycra , a completely synthetic fiber produced by DuPont (Figure 1-12) that has a truly amazing set of properties and is the major component of Spandex (a material that keeps string bikinis on ). Or consider the wrinkle-free polyester fibers used in clothing and the stain proof nylon and polyacrylonitrile polymers used in carpets. The point here is that polymers, be they natural" or synthetic, are all macromolecules but with different chemical structures. The challenge is to design polymers that have specific properties that can benefit mankind. 

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