Preparation and characterization of a new lacquer based on blending urushiol with thitsiol

A new lacquer that blends R. vernicifera (Chinese lacquer, urushiol) with Melanorrhea usitata (Thai lacquer, thitsiol) was prepared. The main properties, viscosities, drying times, drying mechanism, and the nature of the lacquer films as a coating material, were examined. In addition, the mechanism of transfer radical reaction that occurred between urushiol and thitsiol is discussed based on the results of two-dimensional nuclear magnetic resonance (NMR) and field desorption mass spectrometry (FD-MS) measurements. A blended lacquer with 70% R. vernicifera and 30% M. usitata showed almost the same drying time as 100% R. vernicifera as examined in an automatic drying time recorder but had higher surface smoothness and gloss. Furthermore, the molecular weight distribution, UV resistance, and glass transition temperature (Tg) also were investigated in detail. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011