Swiss specialty chemicals producer Clariant (Muttenz; www.clariant.com) has introduced “Exolit” EP 150 and EP 200 reactive phosphorus-based flame retardants that are claimed to provide highly effective fire protection at low dosage levels for epoxy thermosets and laminates in transport and construction applications. The non-halogenated additives are currently available as laboratory product samples and have phosphorus contents of 25% and 29% respectively, enabling only a low dosage of flame retardant to be used to reach the desired protection effect.

Clariant said the materials’ performance has been proven in electrical and electronics applications, where UL 94 V0 fire ratings are achieved at a loading of only 50% of conventional flame retardants.

“Exolit” EP 150 is a low viscosity liquid, making it suitable for use as a flame retardant for infiltration processes, in particular for large-size applications, such as structural parts for aeroplanes and ships, where the ability to flow evenly across a large distance without separating or filtering from the glass or carbon fibre is important for effective, long-term performance. “Exolit” EP 200 is available in solid form – it will melt at higher processing temperatures to provide the same user benefits, Clariant said.

The materials were showcased at the "JEC Europe Composites Show" in Paris at the end of March 2012, alongside Clariant’s “Exolit” OP and AP grades.