Preparation and characterization of Melanorrhoea usitata lacquer film based on pyrolysis–gas chromatography/mass spectrometry

3-(10-Phenyldecyl)catechol was synthesized by the reaction of catechol and 1-phenyl-10-iododecane, followed by de-protection of the hydroxyl groups of catechol; it was then polymerized into synthetic lacquer film by laccase enzyme, and characterized using pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) in order to reveal the polymerization mechanism of Melanorrhoea usitata lacquer. The molecular weight and molecular structure information for each peak in the total ion chromatograms (TIC) were obtained from the mass spectra analysis. In addition, the synthesized 3-(10-phenyldecyl)catechol monomer and its lacquer films were also investigated by IR and NMR measurement. The results showed that quinone produced by the laccase formed a CO bond not with the phenyl group but with the catechol ring of 3-(10-phenyldecyl)catechol, and 3-(10-phenyldecyl)catechol is only polymerized by the laccase to produce a lacquer film.