CHICAGO June 24, 2003 — Two tough new flame-retardant (FR) grades of DuPont™ Zytel® glass-reinforced nylon resins give electrical manufacturers compelling, lower-cost alternatives to thermosets in circuit breaker housings, switchgear, fluorescent lighting and other applications. The new resins are making their debut at NPE 2003 as part of an expanded offering of DuPont engineering polymers and technology delivering improved functionality, aesthetics and/or processing productivity.

"Our new Zytel® FR82G30V0 and FR82G33V1 grades, can deliver substantial cost savings and design benefits compared with thermosets such as electrical-grade BMC (bulk molding compounds),” said Brian Fish, marketing manager for Zytel®. The savings result from faster molding cycles, recycling rather than costly disposal of scrap and designs having more molded-in functional and assembly features. Designs can also use thinner walls to reduce overall part size, according to Fish.

The new resins deliver step change advances in toughness, tracking resistance and short-circuit integrity. Impact strength is more than double that of a typical FR grade of glass-reinforced nylon and far superior to those of phenolic molding compounds. Notched Charpy impact values for Zytel® FR82G30V0 and FR82G33V1 are 19 and 23 kilojoule per square meter respectively using the ISO 180/1a test method.

While many FR thermoplastics (nylons, polyesters and others) crack in 100 kV short-circuit testing, the new Zytel® FR nylons survive. They also score high in tracking resistance with a CTI, comparative tracking index of 1(>400 V) from Underwriters Laboratories (UL).

Zytel® FR82G30V0 carries UL 94 V-0 flame class rating at thickness down to 1. 5 mm. The other resin, Zytel® FR82G33V1, has a V-1 ratin