Phenylone

a trade name that is used in the USSR for the linear aromatic [—NHC₆H₄NHOCC₆H₄CO—]_n polyamide poly-meta-phenylenisophthalamide. The substance is known as No-mex in the USA.

Phenylone is produced by the polycondensation of isophthalic acid dichloride and meta-phenylenediamine in emulsion or solution. It is a white polymer whose glass transition occurs at 270°C; it crystallizes when heated to 340°–360°C and melts at 430°C. The molecular weight of Phenylone varies from 20,000 to 120,000. The polymer dissolves in concentrated sulfuric acid and in dimethyl acetamide and dimethylformamide containing such additives as LiCl and CaCl₂. Phenylone does not burn, it is chemically stable in boiling water, and it resists fuels, oils, certain mineral and organic acids, alkalies, radiation, and mold. Items made of Phenylone have high strength (compressive and flexural strength of 240 meganewtons/m², or 2,400 kilograms-force/cm²) and good dielectic properties (tangent of the dielectric loss angle, 0.01) in the temperature range from –70° to 250°C.

Phenylone is used in the manufacture of fibers, electrical insulating paper, varnish, and films. It also serves as a structural and antifriction material in electrical and radio engineering and in machine building. Fibers and films made of Phenylone are formed from solutions; Phenylone items are produced by pressing and transfer molding at 320°–340°C.