Evaluation of synthesized lacquer films using pyrolysis-gas chromatography/mass spectrometry

The trienyl urushiols, which are major urushiol components, were synthesize d via the Wittig reaction. The synthesized urushiols were then polymerized into synthesized lacquer films by laccase-catalyzed oxidation. The resultin g lacquer films were characterized using Pyrolysis-GC/MS, and the results w ere compared with that of a natural lacquer film in order to evaluate their polymerization mechanism and molecular structure. Based on these results, it was found that natural lacquer films are terminated with the monoenyl an d saturated urushiol, and that the polymerization of synthesized urushiol p roceeds through the laccase-catalyzed nucleus-side chain C-O coupling and a utoxidative side chain-side chain C-C coupling, like the natural lacquer fi lm.