Nonionic Diol Modified UV-Curable Polyurethane Dispersions: Preparation and Characterization

A series of novel water-based UV-curable polyurethane dispersions (UV-PUDs) were synthesized by acetone process with anionic and nonionic stabilization in combination, which can address the requirements of volatile organic compounds (VOCs) directives for both indoor and outdoor applications. The nonionic stabilization was introduced in structure to improve electrolyte stability, shear stability, freeze/thaw stability, etc. The structure of UV-PUDs was characterized by Fourier transform infrared spectroscopy. Molecular weight and molecular weight distribution was characterized by gel permeation chromatography. Particle size was characterized by particle size analyzer. The thermal stability of the cured films was characterized by thermogravimetric analysis, and their performance properties were measured by standard methods. The obtained dispersions were stable for >8 months. It was found that both combinations of anionic and nonionic provide better colloidal stability against electrolytes and shear stability along with comparable performance properties. [GRAPHICS]