Poly(vinyl alcohol)/clay aerogel composites with enhanced flame retardancy

The effect of pentaerythritol octahydrogen tetraphosphate (PEPA) on the microstructure and properties of poly(vinyl alcohol) (PVOH)/clay aerogel composites was investigated. The material obtained after the addition of a flame retardant exhibited an improved mechanical performance, in accordance with a decreased porous size of the aerogel and its rheological property. After the addition of PEPA, the thermal stability of the materials was slightly enhanced. The obtained aerogel composites exhibited good flame retardancy, with a significantly increased limiting oxygen index (LOI), and reduced heat and smoke release. The thermal conductivity of the aerogel composites was not significantly affected by the addition of PEPA, with values ranging from 0.029 W m(-1) K-1 to 0.039 W m(-1) K-1. PVOH/clay aerogel composites with good mechanical properties, thermal conductivity and enhanced flame retardancy have potential applications in the insulation field with requirements for fire safety.