Funding: Spanish Ministry of Innovation and competitiveness (National programme for the promotion of excellence in scientific and technical research) (MAT2014-60435-C2-2-R)
Partners: International Center for Numerical Methods in Engineering (CIMNE) (Project Coordinator), and IMDEA Materials Institute
Region: Spain
Project period: 2015 – 2017
Principal Investigator: Dr. De-Yi Wang (deyi.wang@imdea.org)

Once a fire starts in a closed space containing flammable materials (for example, in a living area of a residential building), these can heat up and ignite. Particularly dangerous are the polymer-made spongy objects (such as mattresses and soft coatings seats) widely used in the household furnishings or interiors of the vehicles. Many of these polymers melt and tend to produce flammable drips or pools, or even fluxes. Thus, the secondary ignition sources may be created and the fire spreads between originally non-adjacent objects drastically increasing the danger of a fire accident.

Nowadays, the risk of such accidents can be considerably reduced by introducing flame retardants (FRs), such as inorganic flame retardant (Mg(OH)2, etc. This is the reason why the use of FRs has become obligatory in multiple industrial fields, such as construction, transport, electrical/electronic engineering, etc. However, the addition of FRs cannot convert the flammable polymers into totally non-flammable ones. Instead, it only slows down the flammability and reduces the heat release during the combustion.

While the fire behavior of these modern materials is known for the lab-scale tests (that are indeed costly), it remains practically unpredictable for the cases of practical importance. The complexity of the configurations encountered in the real-life situations precludes such predictions. On the one hand, large-scale experiments are extremely expensive. On the other hand no corresponding simulation tools exist. The significant difference in thermal decomposition and burning behavior between fire retardant and a neat polymer precludes the use of the existing modelling technology (some effort in the computer modelling of melting and dripping of classical neat polymers had been done), and requires further developments.

Additionally, the currently used FR polymers are either environmentally unfriendly (such as the halogenated FRs), or exhibit low efficiency (traditional halogen-free FRs). Therefore, developing the next generation eco-friendly efficient fire retardants is another challenge.

Aiming at these challenges which are directly related to the fire safety of the society COMETAD project will focus on the following objectives:

• To fully understand the decomposition behavior, mechanism and physical behavior of selected existing FR polymer systems exposed to heat.
• To develop a new numerical tool for FR simulation incorporating the deep understanding of the thermal-decomposition behaviors of FR into an existing multi-physics software of CIMNE.
• To validate the numerical tool for the selected FR polymer systems by performing a set of tailored lab-scale experiments, such as vertical burning test or cone calorimeter.
• To design and develop the next generation of eco-friendly highly efficient FRs. To predict their burning behaviors by the developed numerical tool; the validation will be done by performing experimental fire tests.

Consequentially, the industrial sector such as FR or composites polymer manufacturers will greatly benefit from the project. Providing exclusively the input parameters (such as e.g. viscosity, density vs heat) of a given material they will be able to predict the fire behaviors by using the developed numerical tool. They will also be able to use newly developed eco-friendly FR materials.