Thermal degradation of poly (vinyl alcohol)/poly (vinyl chloride) blend with flame retardants

摘要

The blend which is composed of poly(vinyl alcohol) (PVA) and poly (vinyl chloride)(PVC) is well known as a flame retardant one, but the mechanism of flame retardation of this blend with flame retardants is still not clear. In this work, the effect of flame retardation on the degradation of PVA/PVC blends was investigated by the means of thermogravimetric analysis (TGA), differential thermal analysis (DTA), FT-infrared spectroscopy (FT-IR) and pyrolysis-gas chromatography (PGC). Stannic acid (H_2SnO_3) and antimony trioxide (Sb_2O_3) were used as flame retardants. Blend samples were prepared in the form of films by casting from a single aqueous solution of the two polymers (PVA/PVC weight ratio =1/1) containing the desired amount of H_2SnO_3 or Sb_2O_3. To prepare thus polymer blend, PVA aqueous and PVC emulsion solutions were used in this work.