Federal-Mogul has developed what is believed to be the world’s first polyethylene-terephthalate yarn to meet halogen-free flame-retardant regulations and ’no flaming drip’ requirements.
Until now, no commercially available, zero-halogen, flame-retardant polyethylene terephthalate has been able to meet this requirement, which is known as the UL 1441 VW-1 flame test.
Fire in an enclosed space, such as an aircraft, is extremely dangerous as occupants can die from smoke inhalation before there is any danger from the flames.
Flame-retardant materials delay the spread of fire, but these typically contain halogenated substances that emit thick black smoke and toxic gases.
Polyethylene-terephthalate yarn meets many of the processing and functional requirements for textiles used in interior vehicle trim and wiring harness insulation, which have applications in vehicles for land, water and air.
International regulations pertaining to flame-retardant properties, however, include a requirement that ’no flaming drips’ are released when the material burns.
Federal-Mogul claims that the innovation behind this breakthrough is the combination of two melamine-based flame-retardant materials. As the materials decompose, they absorb heat, cooling the adjacent burning material and forming a char that prevents the formation of burning drips.
Constituents of the new material also vapourise, reducing the surface temperature by diluting the oxygen that would otherwise feed the fire.
Extrusion of the material into a continuous monofilament thread is made possible by a combination of proprietary additives and highly engineered compounding and extrusion processes.
Michigan-based Federal-Mogul is now developing commercialisation plans to enable volume manufacture of fabrics made from the material.