WEB EXCLUSIVE: DuPont Performance Polymers, Wilmington,Del., has just announced the first of a series of nylon compounds designed to preserve high performance much longer than standard nylon 66 when exposed to hot air, hot oil, calcium chloride, and other aggressive automotive chemicals. They are intended to meet more challenging under-hood environments for applications such as charge-air coolers, exhaust mufflers, turbo air ducts, engine mounts, resonators, cylinder-head covers, oil pans, EGR coolers, oil modules, thermostats, transmission components (e.g., front covers), and radiator end tanks. Four initial grades are offered with 30% to 50% glass and optimized for specific environments.
Members of the new Zytel Plus series are based on nylon 6, 66, or a copolymer. (Future additions may be based on DuPont’s Zytel HTN PPA.) It utilizes DuPont “SHIELD” technology, which encompasses a “new polymer backbone,” polymer modifications, and special additives. Zytel Plus is said to provide cost and performance between those of nylon 66 and resins such as PPA and PPS. What’s more, processability (melt flow) of Zytel Plus reportedly is is equal to or better than standard nylons, which is said to be an advange over more costly high-performance resins. Initial mechanical properties and melting point are similar to conventional heat-stabilized, hydrolysis-resistant nylon 66, though Zytel Plus can offer 30% higher gloss and 20% less warpage than corresponding standard nylon. The biggest advantage, however, is shown in tests of retention of tensile strength, elongation, and impact strength after lengthy exposure to hot air (180 C and 210 C) or oil at 150 C . Resistance to hot coolant (water plus ethylene glycol at 120 C) is said to open new doors to applications like thermostat housings. Zytel Plus also boasts double the resistance of conventional nylons to salt mist (calcium chloride). One Zytel Plus grade is optimized for weld-line strength. It shows 60% higher initial strength than heat-stabilized nylon 66 and its strength is unchanged after 500 hr at 210 C, while standard nylon loses one-third of its initial value.
(302) 999-4592 • zytelplus.dupont.com
DuPont Engineering Polymers
PO Box 80713 Wilmington, DE 19880-0713