Coatings with reduced flammability based on environmentally sound coatings

This paper presents the development of environmentally safe paint coatings with reduced flammability based on vinylated alkyd film formers derived from renewable plant raw materials. The obtained materials exhibit enhanced hardness, adhesion and weathering resistance. Inorganic halogen-free flame retardant additives that do not generate toxic decomposition products during thermal degradation were examined and key requirements for the composition and performance of fire-protective coatings were formulated. Flame retardant efficiency was assessed by the flame attenuation length method according to Russian Standard GOST 21227-93. Comparative tests were carried out for coatings containing aluminum hydroxide, magnesium hydroxide, zinc borate and their binary mixtures. It was established that the flame attenuation length decreases monotonically with increasing flame retardant content; minimum values are achieved with zinc borate and Al(OH)₃/zinc borate mixtures owing to a synergistic mechanism – sequential dehydration combined with the formation of a protective glassy surface film. The optimal flame retardant loading in the studied systems was found to be in the range of 6-14 wt%, yielding coatings of reduced flammability category with a satisfactory set of service properties for construction and related industries.