Modification of polyvinyl alcohol/microfibrillated-cellulose films by ethylene triethoxysilane

This study aimed to improve the strength and hydrophobic properties of polyvinyl alcohol/microfibrillated-cellulose composite films and thereby solve problems such as the poor water resistance of polyvinyl alcohol films and defects in the packaging. Polyvinyl alcohol/microfibrillated-cellulose composite films were prepared with the silane coupling agent KH151. The mechanical, optical, crystalline, and other properties of the composite films were tested. After the modification of the polyvinyl alcohol/microfibrillated-cellulose films, their strength and hydrophobic and barrier property were greatly improved. Moreover, their oxygen transmittance decreased by 85.9%, and the water contact angle of the film surface increased by 44%. The internal structure of a polyvinyl alcohol/microfibrillated-cellulose film is formed by KH151, which improves the strength and barrier properties of the film, forms an alkane-based layer on the film surface, and improves the hydrophobic property of the film. Thermogravimetric analysis shows that the thermal stability of composite materials has been greatly improved.