Maude Mermillion-Jimenez

Abstract:

The use of coating, or in a more general way surface treatment, is one of the most efficient ways to protect materials against fire. It has several advantages: it does not modify the mechanical properties of the substrates, it is easily processed and it can be used onto diverse materials such as metallic materials[1], polymers[2], foams[3] and textiles [4]. Moreover, while ignition occurs usually at the surface of a material, it is important to concentrate the protective action at this location. It is the goal of this talk to present recent approaches to make fire protective coatings for different types of plastic based substrates.
When evaluating the fire behavior of materials, the reaction to fire (contribution of the material to fire growth) and the resistance to fire (defined as the ability of materials to resist the passage of fire and/or gaseous products of combustion) have to be distinguished. It means that different scenarios should be considered and hence, different thermal constraints are applied on the protective coatings. According to the fire scenario, the flame retardant coating must be designed with the appropriate chemical composition, thickness, thermophysical and thermo-optical properties.
A well-known example of protective coating is intumescent coating. When heated beyond a critical temperature, the intumescent material begins to swell and then to expand, forming an insulative coating limiting heat and mass transfers. Intumescence is a versatile method for providing both reaction and resistance to fire to materials. Intumescent coatings can be for example applied on carbon fiber reinforced polymers used in aircraft structure for fire protection (i.e. resistance to fire) [5]. Thin intumescent coatings can also be applied on thermoplastics in a cone calorimeter scenario (i.e. reaction to fire). It provides outstanding performance on various polymers, such as polypropylene and polycarbonate [6].
Other technologies than intumescence allow designing FR coatings including laber by layer (LbL)[7,8], sol-gel[9], plasma deposit [10,11], and more recently self-stratifying coatings [12,13] and radiative fire protective coatings [14]. All those methods will be considered in the talk, and the benefit and drawback of these methodologies will be discussed.