Antiglare waterborne polyurethane/modified silica nanocomposite with balanced comprehensive properties

Abstract

To endow antiglare waterborne polyurethane with toughness, thermal stability, and water resistance is highly desired. Herein, we first prepared amphiphilic polyurethane modified silica (MSiO2) nano-particles by in-situ polymerization and then physically incorporated it with waterborne polyurethane (WPU) dispersion to fabricate WPU composite (WPU-MSiO2). The FT-IR, TG-DTG, and SEM analyses demonstrated that the urethane chains were covalently attached onto the silica surface, and the MSiO2 exhibited good dispersibility and compatibility with WPU matrix. Moreover, embedded MSiO2 particles could not only impart the WPU-MSiO2 composites with good antiglare function, but also improve the mechanical, thermal, and water resistance of composites. Notably, the most effective enhancements in antiglare and other physicochemical performances were achieved when incorporating 3 wt% of MSiO2 into the WPU dispersion to fabricate the WPU-MSiO23 composite. In particular, the WPU-MSiO23 composite film possessed the transmittance of 94.6% and 60° gloss of 27.0, respectively, which satisfying the requirement of an antiglare coating. Furthermore, WPU-MSiO23 composite exhibited great increase in tensile strength, elongation at break, maximum decomposition temperature, and water contact angle (20.8 MPa, 636.5%, 389.5 °C, and 99.1°, respectively) as well when compared to the neat WPU and WPU-SiO23 films. The present research provided a cost-effective way for preparing high-performance antiglare polymer coatings.

Keywords

• Waterborne polyurethane composite
• Modified nano-silica
• Mechanical
• Thermal
• Antiglare