According to importance of the safety issues especially in air industry, fire-resisted parts and interiors consumption are increasing. Seat foam has a huge fraction of the airplane interior and this makes it essential to become safer. From another point, planning to phase out some of the halogenated flame retardants because of persistence in the environment, bioaccumulation, and toxicity. In recent years, halogen-free fire retardants have been more investigated. In this work, we have concentrated more on two well-known, solid, halogen-free fire retardants, expandable graphite and melamine, and compared their performance according to their fire behavior, physical properties, and production phenomena.

Regarding the increasing demands for the fire resistance polyurethane foam for train and airplane industry and a serious planning to phase out the halogenated flame retardants (FR) because of high and toxic smoke generation, the use of halogen-free fire retardants have been more investigated in recent years. In this work, we have concentrated more on two well-known solid halogen-free fire retardants, expandable graphite, and melamine with two grades of each one and compare their performance in a variety of areas including reactivity, physical and mechanical properties, and fire behaviors and finally the tendency of each FR to have a synergetic effect with each other. The obtained results show that the addition of these two FR affect significantly on reactivity and physical—mechanical properties such as recession factor, expansion factor and compression load deflection (CLD P25/5), sag factor, compression set, tear strength, resilience, and more efficiently on fire behavior of flexible polyurethanes foam.

In this study, numerical approach for simulation of mold filling is presented. Polyurethane foam formation includes several complex phenomena such as chemical reactions, heat generation and blowing agent evaporation. Foam properties are variable during formation, foam viscosity increases and conductivity reduces. Foam phase is considered compressible and two phases are immiscible. Foam front will be captured by volume of fluid and appropriate governing equations will be implemented in OpenFOAM. This study prepares a numerical model to reduce several experimental runs with expensive prototypes for mold design.