Mechanical and water resistance properties of chitosan/poly(vinyl alcohol) films reinforced with attapulgite dispersed by high-pressure homogenization

Attapulgite (APT) is a natural one-dimensional nanorod with higher mechanical strength and shows great potential as an effective reinforce filler for deriving nanocomposites. The dispersion degree and aspect ratio of APT are keys to decide the performance of nanocomposites. However, natural APT cannot develop its nanometer reinforce advantages because it usually appears as a crystal bundle or aggregate. In this work, we effectively disaggregate the crystal bundles of APT by a simple high-pressure homogenization technology at various pressures. The obtained nanometer APT as an ideal reinforce filler was introduced into chitosan (CS)/poly(vinyl alcohol) (PVA) matrix to derive a series of nanocomposites by the solution casting method. The CS/PVA/APT nanocomposites were characterized by field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). Tests results indicated that the nanometer APT can enhance the mechanical properties and water resistance of nanocomposites more obvious than pristine APT. The nanocomposites also were shown to be highly transparent and the introduction of APT into CS/PVA matrix nearly not affected the optical property of the films.

Figure optionsDownload as PowerPoint slideHighlights
► APT by high-pressure homogenization can well disperse in the CS/PVA matrix.
► Mechanical properties of CS/PVA/APT films increase due to disaggregate of crystal bundles.
► Water resistances of CS/PVA/APT films are improved according with homogenization pressures.
► Introduction of APT into CS/PVA matrix nearly not affected the optical property.