Nylon fibers, description

Caprolactam Extraction. A high degree of purification is necessary for fiber-grade caprolactam, the monomer for nylon-6 (see Polyamides). Cmde aqueous caprolactam is purified by solvent extractions using aromatic hydrocarbons such as toluene as the solvent (233). Many of the well-known types of column contactors have been used a detailed description of the process is available (234). 

The reinforcement of rubbers using nylon, rayon, vinyl, and polyester fibers was reported by various authors [10,58,73-75]. Because of the design flexibility and suitable end-use applications, high-performance fibers such as glass, carbon, and aramid also find extensive applications in short fiber-reinforced mbbers. A brief description of some of the major high-performance fibers commonly used in short fiber-rubber composites is given below ... 

Because of its extremely low solubility in low-boiling and inexpensive organic solvents, nylon 66 required a new technique for converting the solid polymer into fibers hence the development of melt spinning, the third basic method for producing manufactured fibers. The following description refers essentially to nylon 66 because it was the first to use the method, but the process applies, in general, to all melt-spun manufactured fibers. 

This ehapter will be presented in two sections — one for natural fibers (cotton, wool, blends, etc.) and one for synthetie fibers (nylon, polyester, blends, ete.). Each section will review many of the more eommon NIR analyses, methods, and teehniques for textile products. Both laboratory and at-line/on-line NIR analyses will be reviewed. In addition, a more detailed description will be provided in eaeh section for a few of the more eommon NIR textile techniques. Even though most textile readers may have prior knowledge of some of these detailed applications, it cannot be assumed that all readers are familiar with all of them. Thus, background and a brief preparatory description of the textile proeess and materials prior to each detailed applieation will be given, as well as specific references for those who wish to study the subjeet in greater detail. 

Our analysis of fiber spinning in this chapter will be based on an inelastic rheological model of the stresses. This rheological description appears to be adequate for polyesters and nylons, which comprise the bulk of commercial spinning applications, and our spinning model is essentially the one used in industrial computer codes. This is a process in which melt viscoelasticity can sometimes play an important role, however, and we will revisit the process in Chapter 10. 

---