In response to health, safety and sustainability needs - primarily for electrical applications such as contactors, circuit breakers and housings - DuPont Performance Polymers has extended its portfolio of halogen-free* materials, with a new flame-retardant (FR) nylon 66 with enhanced thermal ageing.
"In a comparative test carried out on ISO tensile bars according to ISO 527 in DuPont's European Technical Center in Geneva, Switzerland, data showed that our halogen-free nylon 66, DuPont Zytel® FR95G25V0NH, retains 80 percent of its tensile strength when exposed to 200 °C for more than 1,000 hours, while incumbent materials only retain 50 percent", said Antonio Nerone, global segment leader electric & connectors.
The new Zytel® FR grade uses a patented combination of flame-retardant copolymer and stabilizer to improve melt stability, flow and surface appearance and reduce mold deposit. The new material also offers a Comparative Tracking Index (CTI) rating of 600V. This rating is given to polymeric materials to compare their resistance to carbon tracking and is determined by test methods defined by IEC 112 or UL 746C. The CTI value is subsequently used for electrical safety assessments of electrical apparatus. Applications that can take advantage of this level of performance will typically include the insulating elements and housings for circuit breakers, contactors, transformers and motors.
The electrical industry is seeking alternatives to the use of halogens as flame retardants for health, safety and recycling reasons. It also has to consider the WEEE (Waste Electrical and Electronic Equipment) Directive, which requires the separation of halogen-containing materials.
DuPont is constantly evolving its range of halogen-free products and is also working on the development of halogen-free DuPont Crastin® PBT, DuPont Rynite® PET, DuPont Hytrel® TPC-ET and Zytel® HTN, all of which have been developed to address industry requirements.
*Halogen-free when used herein means that halogen is not an intended ingredient of our product.