Effect of Relative Humidity on the Mechanical Properties of Micro and Nanocomposites of Polyvinyl Alcohol

The effect of relative humidity on the mechanical properties of poly(vinyl alcohol) (PVOH) micro and nanocomposites was evaluated. Two different commercial fillers (microcellulose and bentonite) were used as reinforcement. PVOH and PVOH composite films were prepared by casting technique. The incorporation of microcellulose increased the content of water absorption and the modulus, especially for the higher contents of filler. The effect of reinforcement on the mechanical properties was more pronounced at higher relative humidity. On the other hand, the incorporation of nanofiller produced a decrease in water absorption probably due to the decrease of mean free path of water molecules. The modulus of the nanocomposites improved from the matrix, but the mechanical properties are deteriorated by effect of the humidity.