Abstract

A polyurethane/polyacrylate/silica nanocomposite was prepared by seeded emulsion polymerization using polyurethane as a seed emulsion and potassium persulphate (KPS) as a free radical initiator, in which silica was synthesized via the sol-gel method of tetraethoxysilane (TEOS) and was modified by vinyl triethoxy silane (A-151). The influence of synthesis conditions such as the polyurethane and SiO2 content on the physical-mechanical properties and water resistance of polyurethane/polyacrylate/silica nanocomposite was investigated in detail. The tensile strength and elongation at break of nanocomposite films, at first, increases and then decreases with the increasing content of polyurethane. The incorporation of silica leads to improved tensile strength, but the elongation at break decreased. Water uptake measurements confirmed that the water resistance of polyurethane/polyacrylate/silica nanocomposite was improved by the introduction of polyurethane and silica.

The improved properties of the leather finished by polyurethane/polyacrylate/silica nanocomposite are shown, in contrast to polyacrylate finish. The water vapour permeability was increased by 7.14% and the water resistance by 30.34%.