SYNTHETIC TEXTILE FIBERS — MAUERSBERGER 221 



percent. The fibers lose strength when abraded and hence, unless they 

 are protected by a flexible coating, are not suitable for applications 

 involving severe bending or creasing. While the fibers themselves are 

 waterproof, fabrics woven from them are more susceptible to mechan- 

 ical damage when wet than when dry. Resistance of j-arns and 

 fabrics to abrasion has been improved considerably since fiberglas was 

 first introduced, and further progress along that line is expected. 

 At temperatures above 600° F. there is a loss in tensile strength, and 

 at 1,500° to 1,600° F. the fibers start to soften or melt. Fiberglas 

 yarns are approximately two to two and a half times as heavy as 

 cotton yarns of the same diameter. 



Fiberglas yarns can be woven, braided, or knitted on the usual types 

 of textile equipment. During manufacture a small amount of lubri- 

 cant is added to the yarn. Special formulas for warp sizing have been 

 worked out. Fiberglas cannot be dyed satisfactorily by any of the 

 usual processes. Some experimental work has been carried out on 

 printing fabrics with lacquer colors. 



For the present, fiberglas textiles have been confined to industrial 

 and decorative purposes. Some knitted fabrics have been produced 

 experimentally. Aside from shoe fabrics, no attempt has been made 

 commercially to manufacture fabrics for wearing apparel. Among 

 the more important industrial applications are filter fabrics; yarns, 

 braids, tapes, and other materials for electrical insulation purposes; 

 anode bags used in the electroplating industry ; wicking for oil stoves 

 and lamps; pump diaphragms, and belts for resisting high tempera- 

 ture, fumes, and acids. Draperies made from fiberglas are now on 

 the market in a wide range of designs and colors. Among other po- 

 tential household uses are tablecloths, bedspreads, curtains, uphol- 

 stery, wall coverings, and awnings. Still other applications are rope, 

 twine, and sewing thread for sewing glass textiles. 



FILAMENTS AND FIBERS FROM CHITIN 



Chitin was discovered in 1811 by Braconnot and is a polysaccharide 

 containing nitrogen, present in the cell walls of fungi and the skeletal 

 structure of such invertebrates as crabs, lobsters and shrimps. Like 

 cellulose it may be acetated, but has little resemblance to cellulose 

 and is quite different from fibroin. Rigby in his United States 

 patents deacetylated chitin in 1936, and the product as well as many 

 of its salts may be used for the manufacture of films and filaments. 

 He has used a 3-percent aqueous solution of medium viscosity 

 deacetylated chitin acetate for films, filaments, and for cementing 

 paper sheets, the product being insolubilized by exposure to 

 ammonia fumes. 



