Investigation of the Processes of Formation of Water-Dispersible Polyurethane Acrylates Based on Oligomeric Isocyanurates of Isophorone Diisocyanate

Abstract

A series of oligoisocyanurates of isophorone diisocyanate with different conversion of isocyanate groups have been synthesized in the presence of a 1,4-diazabicyclo[2.2.2]octane/propylene oxide catalytic system. The obtained samples have been characterized by IR and ¹³C NMR spectroscopy. It has been shown that the ratio of aliphatic and cycloaliphatic isocyanate groups in the oligoisocyanurates is close to that in the monomer. Investigation of kinetics of the urethane formation involving isophorone diisocyanate and its oligoisocyanurates with 2-hydroxyethyl methacrylate in the acetone medium has revealed that the presence of traces of the catalytic system in oligoisocyanurates significantly contributes to the urea formation reaction. In this regard, the synthesis of water-dispersive polyurethane acrylates based on isophorone diisocyanate oligoisocyanurates has been carried out in the medium of a hydrophobic solvent, methylene chloride. According to the analysis of the hydrodynamic parameters of the obtained aqueous dispersions, the size of the particles of the dispersed phase increases with an increase in the conversion of isocyanate groups in the oligoisocyanurates of isophorone diisocyanate. The observed regularities are apparently due to an increase in the content of the high-molecular fraction in the corresponding oligoisocyanurates.