Development of a flexible, low-viscosity epoxy acrylate for UV-curable coatings - News and insights for the European coatings industry

Neuartiges Epoxyacrylat bietet verbesserte Flexibilität und geringere Viskosität, ideal für UV-härtbare Anwendungen.

In a recent article published in the Journal of Coatings Technology and Research, Yumei Zhou and Jinqing Qu introduce an innovative low-viscosity, highly flexible epoxy acrylate for UV-curable coatings. Conventional epoxy acrylates are often limited by high brittleness and viscosity. This study addresses these issues using a carboxyl-terminated intermediate derived from anhydride and diol to modify the epoxy acrylate, with flexibility adjusted via the carbon chain length in the diols. By replacing E51 with binary glycidyl ether, resin viscosity was reduced from 29800 to 13920 mPa·s (at 25°C), and film flexibility improved from 12 to 1 mm.

Due to their outstanding properties, epoxy resins are more widely used in the coating industry than almost any other class of binder. In their new reference book “Epoxy Resins”, the authors Dornbusch, Christ and Rasing explain the basics of the chemistry of the epoxy group and use specific formulations to explain the use of epoxy and phenoxy resins in industrial coatings – including corrosion protection, floor coatings, powder coatings and internal can coatings.

This method offers cost-effective production with readily available raw materials, a low reaction temperature under 130°C, and no need for organic solvents, making it a streamlined and efficient process. The improved properties and simplicity could broaden the use of UV-curable epoxy acrylates across various industrial applications.

Source: Journal of Coatings Technology and Research, Volume 21, pages 601–610 (2024)