chapter  2
26 Pages

Surface Characteristics of Polyester Fibers

I. Introduction 34

II. Chemical Structure of Polyesters 36 A. Polyethylene terephthalate 36 B. Other polyesters 36 C. Copolyesters 39

III. Surface Structure and Chemistry 40

IV. Surface Energy and Wetting Contact Angle 42

V. Surface Effects from Fiber Spinning 44 A. Fiber size and cross-sectional shape 44 B. Drawing and heat 45

VI. Surface Modification 46 A. Alkaline hydrolysis 46 B. Enzyme hydrolysis 48 C. Low-temperature plasma 49 D. Surface grafting 52 E. Excimer UV laser 53 F. Other methods 53

VII. Summary 54

References 55

I. INTRODUCTION Polyester has been one of the most popular fibers, second to cotton as measured by production tonnage in recent years. The technical merits and commercial ver­ satility of the fiber production system have led to successful product development and applications. Polyester fibers have many desirable properties, including rela­ tively high tenacity, low creep, good resistance to strain and deformation, high glass transition temperature, and good resistance to acids and oxidizing agents. These physical, mechanical, and chemical attributes make polyester fibers excel­ lent candidates not only for apparel and textile products but also for industrial and composite applications. In apparel, for instance, polyester fibers are versatile because of their receptivity to heat treatments (setting and texturing) and the ease of their blending with other fibers such as cotton, wool, and regenerated cellulosics. However, polyester fibers also possess certain characteristics which constrain their use. Polyester fibers retain little moisture and do not transport aqueous fluids. The hydrophobic nature of polyester fibers makes them difficult to dye (they require a carrier) and to finish in aqueous media. Their oleophilic nature attracts oily soils and leads to poor adhesion to rubber and plastics. Polyesters also have poor resistance to alkalis.