◆ SpookStack

66 (75% of U.S. consumption) and nylon 6 (25% of U.S, consumption). Except for slight difference in melting point, the properties of the two forms are almost indentical, though their chemical derivations are quite different. Other types are nylons 4, 9, I, and 12 (see Grades). Properties: Crystalline, thermoplastic polymers. May be extruded ‘as monofilament over a wide dimen- sional range. Filaments are oriented by cold-drawing. Tensile strength (high-tenacity) up to 8 grams per denier (about 100,000, pi). Sp. gr. 1.14, Melting point (66) 264°C; (6) 223°C. Low water absorption. Good electrical resistance, but accumulates static charges. Highly elastic, with rather high percentage of delayed recovery at low strain values, tow perma: nent elongation. Moisture absorption 4% at 65% R. H. Wet strength about 90% of dry strength. Can be dyed with ionic and nonionic dyestuffs. Attacked by mineral acids, but resistant to alkalies and cold abrasion. Soluble in hot phenols, cresols and formic acids; insoluble in most organic solvents. Difficult to ignite; self-extinguishing: melts, forming beads. Re- sistant to attack by moths, carpet beetles, etc. Com- patible with wool and cotton; increases wear and Crease resistance in 30% blends with natural fibers. Nontoxic. Rods and blanks are machinable. Forms: Monofilaments, yarns, bristles, molding pow- ders, rods, bars, sheets. Microcrystalline nylon is now available. Grades: Nylon 66 is a condensation product of a¢ igic acid and hexamethylenediamine developed by rothers (q.v.) in 1935. Adipic acid is obtained. by catalytic oxidation of cyciorexane. Nylon 6 is a poly- mer of caprolactam (9.v.). originated by 1. G. Far- benindustrie in 1940. Nylon 4 is based on butyrolac- tam (2-pyrrolidone), its tenacity, abrasion resistance, and melting point are said to be about the same as for the 6 and 66 grades. It has excellent dyeability. See “Tajmis.” Nylon 610 (trademarked “Tynex”) is obtained by condensation of sebacic acid and hexamethylenedia- mine, and nylon 11 (trademarked “Rilsan") from castor bean oil (developed in France}. Nylon 12 (also called “Rilsan” 12) is made from butadiene, also by a French process involving photonitrosation of cyclo~ dodecane by actinic light from mercury lamps. Its properties are similar to those of nylon 11. Nylon 9 can be made from 9-aminononanoic acid, present in soybean oil. It has properties specifically desired in metal coatings and electrical parts; higher electrical resistance than 6 and 66; absorbs less moisture; and has better distortio1 Uses: Tire cord; hosie: bristles for toothbrus| ‘earing apparel component; hairbrushes, paint brushes NYTRIL {nylon 610); cordage and towlines for gliders; fish nets and lines; tennis rackets; rugs and carpets; molded products; turf for athletic fields; parachutes; composites; sails; automotive upholstery, film; gears and bearings; wire insulaton; surgical sutures; arti- ficial blood vessels; metal coating. pen tips, asmatic membranes; fue) tanks for automobiles. See also polyamide; aramid Note: Not all nylons are polyamide resins, nor are all polyamide resins nylons, e.g. “Versamide.” One class of polyamide resins distinct from nylons is derived from ethylenediamine; they may be liquids or low- melting solids and have lower molecular weight than nylons. Another class, called aramids, is aromatic “NyoGe." Trademark for a series of low shear thixotropic greases and semifluid instrument lubri- cones fee use where nonspreading properties are critical. “NyoSil.”? Trademark for a wide temperature sili- cone instrument oil halogenated for improved wear Properties. Viscosity 55 centistokes at 100°F. nystatin (fungicidin) C4sH»;NOy. An antifungal agent. ropertics: Yellow to light tan powder, odor sugges- tive of cereals; hygroscopic; aftected by light, heat, air and moisture. Sparingly soluble in methanol, ethanol; very slightly soluble in water; insoluble in chloroform, ether and benzene. In solution is rap- idly inactivated by acids and bases. Nontoxic. Derivation: Produced by fermentatoin with Strep- tomyces noursei and aureus. Grades: U.S.P. Use: Medicine; feed additive. “Nytal."? Trademark for tale or magnesium-calcium silicate. Uses: Dusting uncured rubber, filler in specialized applications. nytril, Generic name for a manufactured fiber con- taining at least 85% of a tong-chain polymer of nylidene dinitrile. --CH,C(CH),—, where the viny lene dinitrile content is no less than every other sai ia the polymer chain (Federal Trade Commis- sion). Properties: Soft, resilient fabric is obtained; is easy to clean; does not pill; resists wrinkling, and retains shape after pressing. Uses: Fur-like pile fabrics; sweaters; yarns; blended fabrics for coats and suits, Superior numbers refer to Manufacturers of Trade Mark Products, For page number see Contents. fs. 2S; KE & AY ee tees > i AES te Vas SS Eo cn Bee ee ie