Enhancement in thermal properties of poly(vinyl alcohol) nanocomposites reinforced with Al ₂ O ₃ nanoparticles

Abstract

In the present study, poly(vinyl alcohol)/Al 2 O 3 nanocomposites of various compositions were produced through ultrasound-assisted technique. The nanocomposites were prepared by mixing a colloidal solution consisting of Al 2 O 3 nanoparticles with a water solution of poly(vinyl alcohol) and then hybrids films with different contents of inorganic phase were obtained after solvent evaporation. Field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and UV-visible spectroscopy were utilized to characterize the poly(vinyl alcohol)/Al 2 O 3 nanocomposites morphology and properties. Thermogravimetric analysis and UV-visible results indicated that the thermal stability is enhanced distinctly, without a sacrifice in optical clarity. The improvement of thermal properties was attributed to the homogeneous and good dispersion of Al 2 O 3 nanoparticles in the poly(vinyl alcohol) matrix and the strong hydrogen bonding between O–H groups of poly(vinyl alcohol) and the oxygen atoms of nanoparticles. On the whole, the poly(vinyl alcohol)/Al 2 O 3 nanocomposite systems had thermal properties, which were superior to that of the neat polymer and its conventionally filled composites.