- Flame Retardants
The Fire Retardant Technologies Conference FRT09, Preston, UK, 21st to 23rd April 2009, covered flame retardancy mechanisms in general and for the various families of flame retardants (based on halogens, phosphorous, nitrogen, inorganics and nanocomposites), fire and toxicity testing, as well as environmental aspects. The conference with 18 papers and 22 posters was well attended (over 100 participants and 18 speakers), and gave a good overview on status and new developments in this widespread field.
The conference started with two overview papers: the first described the families of flame retardants and their mode of action, while the second covered the main flammability and heat release tests, as well as analytical methods for determining basic properties of specific flame retarded polymer systems (TGA, GCMS, FTIR, rheometry).
The next session went into more details regarding the use and applications of brominated flame retardants in various polymers, the mineral flame retardants and those commercially used today, the mode of action of phosphorous-based flame retardants and the inorganic, organic and reactive compounds used, practical applications of intumescent coatings for structural steel protection, as well as commercial intumescent fire retardants for cable applications based on calcium carbonate, silicon elastomers and polyethylene copolymers. The session finished with a comprehensive overview on nanocomposites (boehmite, carbon nanotubes, organoclays) used for improving the flame retardancy of various polymers.
The following presentations dealt with the use of expandable graphite in various flame retardancy applications, and with cold plasma induced graft polymerisation for coating and flame retarding textiles. The last paper gave some very interesting insights into the flame retardant mechanisms of metal phosphinates used in polyamides (PA6 and PA66) and linear polyesters (PBT).
Fire safety regulations, tests and new fire performance approaches were discussed in the next session. Fire safety requirements and tests for building, transportation, electrical engineering and electronics (E&E) become more and more international, but are still based on prescriptive tests. However, in some countries such as Poland, fire performance approaches will be introduced in building regulations. In the second paper, it was shown that flammability test data allow the interpretation of the fire retardant behaviour of products used in buildings and thus to develop a fire performance based approach for a whole building. The third paper dealt with flame retardants and their impact on the toxicity of fire effluents. It was shown that carbon monoxide may not always be the most important deadly toxic fire gas component; other asphyxiants (HCN) or irritants (HCl) also play a determining role in the acute toxicity of fire effluents.
The last session was devoted to environmental aspects and started with an overview on environmental requirements related to flame retardants (REACH, RoHS), the chemical safety assessment of a halogenfree flame retardant (aluminium phosphinate) in its life cycle (production, processing, use phase, recycling), and the current environmental activities related to the use of halogenfree alternatives to some brominated flame retardants, particularly in E&E. The next paper described the environmental and sustainability aspects of brominated flame retardants, the reduction of emissions through the Voluntary Emission Control Action Program VECAP and the benefits of polymeric brominated flame retardants regarding their impact on the environment. The last paper of the conference covered environmental concerns related to brominated flame retardants with focus on the persistence, bioaccumulation and toxicity of polybrominated diphenylethers, and also of other flame retardants such as hexabromocyclododecane.
The conference gave an excellent picture of the status and trends of flame retardants, their mode of action and use in polymers, fire safety regulations, testing, and environmental aspects. The conference programme is available under: