DU PONT PRODUCES DURABLE FIBER HYTEN OUTLASTS POLYESTER, NYLON

DU PONT PRODUCES DURABLE FIBER HYTEN OUTLASTS POLYESTER, NYLON

E.I du Pont de Nemours & Co. has begun commercial-scale production of a high- strength polyamide fiber used in tires, rubber goods and a variety of other specialized uses.

The new fiber, called Hyten, is substantially stronger than nylon or polyester cord because it can be used in a single filament, without reducing its durability, said Gregory Henning, a research associate with Du Pont's fibers division."Several filaments of nylon must be twisted" for higher-strength applications, Mr. Henning said. "Hyten can be used for the same applications in a monofilament," he said.

As a result, Hyten cord is 38 percent stronger than polyester cord and 10 percent stronger than nylon.

Mr. Henning explained that twisting fibers is normally needed to extend the life or durability of the cord, but that twisting weakens it in the short term. While nylon filament starts out at a strength of 9.5 grams per denier, twisting it reduces that strength to 8 grams per denier. Hyten has a strength of about 9 grams per denier, and maintains that in actual use, since it can be used as a single filament.

The new fiber is being tested in high-performance automobile tires, which currently rely on twisted nylon cord for sidewall and steel-belt covering.

Mr. Henning said most major tire manufacturers have tested the fiber, and expect that it will be used in several high-performance tires this year.

Du Pont claims that using a single filament will simplify tire manufacturing and permit up to a 15 percent savings on rubber.

Mr. Henning said that Hyten also is used in mechanical rubber hoses in automobiles and boats, to make fishnets and in extra-long fishing line.

He added that Hyten already has been used for re-stringing tennis rackets.

Du Pont is manufacturing Hyten at its Chattanooga, Tenn., plant. The plant has capacity for several million pounds of the fiber a year.

E.I. du Pont de Nemours & Co. is based in Wilmington, Del.