New flame retardant increases fire resistance
Empa and a partner company have developed a new flame retardant for wood and wood-based materials. The colorless additive, which mixes well with varnish and cellulose materials, opens up new applications for wood-processing companies.
All over the world, fire protection requirements are increasing - especially in public buildings or vehicle construction. This development means that more and more otherwise suitable materials, such as wood, can no longer be used in many buildings or means of transport and have to be substituted by other products. The aim of the research project supported by the CTI (Commission for Technology and Innovation) was therefore to develop a flame retardant that increases the fire resistance of such materials without impairing their positive properties.
Colorless, non-toxic additive
The new flame retardant called Anti-Flame Additive (AFA) meets these specifications: It is colorless and can be mixed with water-based coatings or UV protective coatings and can be used not only as a coating layer but also as an additive in wood-based panels. In addition, it is free of bromine and boron, does not contain halogenated organic compounds. It does not produce any toxic vapors and develops its flame-retardant effect at concentrations as low as ten percent.
AFA is based on the Empa-developed substance EDA-bis-TEPT, a flame retardant from the class of organophosphonates. It combines phosphorus and nitrogen moieties in a single molecule and has flame retardant effects on cellulose. The new additive developed has already shown its effectiveness in internal tests and has been protected with a patent application since 2018. Application tests are currently being conducted: For example, the admixture of AFA to various commercially available building materials and paint systems is being tested.
Admission procedure underway
Initial tests with major wood-based panel manufacturers have been positive. The same applies to the world's third largest manufacturer of HPL (High Pressure Laminates). Once the AFA has been introduced into the celluose during production, the material is reliably prevented from catching fire. In a further step, AFA will undergo the fire protection and approval tests required for approval.
EDA-Dopo is Reach registered
Another flame retardant developed at Empa is called DFA-Dopo and is already one step closer to commercial use. It contains no environmentally harmful halogens and has been registered in the EU chemicals database Reach since last fall.
The registration of a newly developed substance is very complex and represents an important milestone for commercial marketing: Reach-registered substances are considered safe for people and the environment. They may be transported throughout the EU without a dangerous goods class, even in larger quantities, and can also be used in residential buildings, public buildings and public transport.
