ABSTRACT

Acrylic fibers are defmed by the U.S. Federal Trade commission as having at least 85% by weight of acrylonitrile units (-CH2-cH[CN]-). Modacrylic fibers are defmed as being composed of at least 35% but less than 85% acrylonitrile units by weight. Modacrylic fibers are less suitable for apparel end uses compared to acrylic fibers because, generally, they are higher priced, yellower, and have lower dimensional stability to heat. Therefore, the consumption of modacrylic fibers is very limited in apparel and reference to them will be confmed to the one or two markets where they are utilized to a small extent.