Achieving Enhanced Fire Safety of Polyvinyl Chloride Through Rapid Catalytic Carbonization Using a Triple-effect Flame Retardant of Mg(OH)₂-ZnO-TiO₂

The concept of catalytic flame retardancy by metal ions is considered an efficient flame-retardant method. However, due to the unclear mechanism, the ambiguity of the reaction process and the unknown properties of the products severely limit its application in composite materials. In view of this, we designed a tri-effect composite flame retardant of Mg(OH)₂-ZnO-TiO₂, which not only solves the problem of low flame retardancy efficiency of magnesium hydroxide (MH) but also performs excellently in the evaluation of flame retardancy of polyvinyl chloride (PVC). The limit oxygen index (LOI) increased from 21.5% to 31.1%, and the composite material can be synthesized on a large scale. Through detailed analysis of the condensed phase carbon layer, two different catalytic flame retardant mechanisms were elucidated. This research is expected to provide an important theoretical basis for the development of efficient and environmentally friendly composite flame retardants.