Novel oxidatively drying urea resin. II. Surface coating properties of N,N′‐bis(methoxymethyl) urea‐based air‐drying resins

Abstract

AbstractThe surface coating properties of the air‐drying urea resins prepared by polycondensating N,N′‐bis(methoxymethyl) urea (BMMU) with trimethylolpropane diallylether (TMPDA) and 2‐ethylhexanol (2EH) were studied. It was found that the thinnability of the ethanolic resin solutions with water decreased with increasing molecular weight and the degree of modification of the resins with TMPDA and 2EH. The viscosity of the ethanolic resin solutions increased with the molecular weight but was independent on the resin's degree of modification. The drying performance was improved with increasing molecular weight and decreasing modification with 2EH. The hardness of the paint films was proportional to the modification of the resins with TMPDA and the molecular weight. 2EH led to the plasticization of the coatings. The water resistance of the paint films was improved with increasing modification with 2EH and molecular weight of the resin. The analysis of the elastic properties of the hardened films was not possible due to the scatter of the experimental data. The comparison of the amino resin paints to some commercial paint products indicated that BMMU‐based resins having good drying performance and adequate water resistance at the same time can be prepared. Neutral ethanolic and aqueous ethanolic resin solutions were found to have a good storage stability as determined by following the viscosities of the solutions and the hydrolysis resistance of the resins.