Nanocomposites based on poly(vinyl alcohol) and a-titanium phosphate were prepared by the solvent-cast method. The alpha-titanium phosphate nanosheets were homogeneously dispersed in the poly(vinyl alcohol) matrix, and marked property enhancements were obtained. In thermogravimetric analysis, the maximum decomposition temperature of the nanocomposites was increased by 80 degrees C, and the value of maximum decomposition was reduced by 60%. The storage modulus and tensile strength were improved by 64% and 84%, respectively. According to microscale combustion calorimetry, the ignition temperature (89 degrees C) and the temperature for peak heat release rate (192 degrees C) were significantly increased, whereas the peak heat release rate was sharply reduced (79%). The property enhancements are mainly due to strong hydrogen bonds between the poly(vinyl alcohol) and alpha-titanium phosphate nanolayers, as well as the molecule-movement-restricting and physical-barrier effects due to the alpha-titanium phosphate nanolayers. In addition, the effects of the water content and alpha-titanium phosphate amount on the electrical conductivity of poly(vinyl alcohol) nanocomposites were investigated.