Ce-MOF nanorods/aluminum hydroxide (AlTH) synergism effect on the fire-retardancy/smoke-release and thermo-mechanical properties of a novel thermoplastic acrylic intumescent composite coating

The development of novel fire/smoke-retardant agents for the intumescent polymeric-based coatings has grown expeditiously in recent researches. The use of ammonium poly-phosphate, [NH4PO3]n(OH)2, (APP), pentaerythritol, C5H12O4, (PER), and Melamine, C3H6N6, (MEL) mixture has been acknowledged as the reliable intumescent system for the coatings. However, there are a number of auxiliary materials which have been introduced for these intumescent coatings with the aim of decreasing the heat transfer, smoke production, and radical release and also increase of char strength, corrosion protection, and mechanical properties of the coatings. In this work, we synthesized cerium-based Metal-organic framework (MOF) nanoparticles as an additive for the acrylic-based intumescent system. The synthesis of MOF was proved and characterized by FE-SEM, XRD, and BET analysis. The effect of incorporation of the obtained MOFs and Aluminum hydroxide (AlTH) and also the synergistic effect of simultaneous use of these additives in the intumescent formulation on the fire retardancy, morphological and mechanical properties of char layer, and also the mechanical properties of the coating were studied in detail. The results showed that the synergism behavior of MOF and AlTH increased the heat-insulating index of the system by about 17%, and decreased the heat release rate and smoke production rate to 24.78 KJ/m2 and 31.84 m2, respectively. The synergistic effect of the additives has also improved the char forming, char strength and also hindered the detrimental effect of the intumescence system on the mechanical properties of the coating. The intumescence mechanism of the proposed coatings was discussed in detail using the results of TGA and FTIR analysis and study of decomposition kinetic.