The thermal decomposition mechanism of zinc monosalicylates

alpha-Zn(o-OC6H4CO2) and beta-Zn(o-OC6H4CO2) with different structures were synthesized by the rheological phase reaction method and thermal decomposi tion method, respectively. The TG, DTG and DTA curves were measured in N-2. alpha-Zn(o-OC6H4CO2) at 409 degrees C, beta-Zn(o-OC6H4CO2) at 375 degrees C, started to decompose, and form zinc oxide, dibenzofuran, xanthene, xanth enone, 1,2-dibenzopyrone and 2-phenyl-1,2-dibenzopyran, etc. The products o f thermal decomposition were characterized with infrared spectra, powder X- ray diffraction and gas chromatography and mass spectrography. The thermal decomposition reaction mechanism is discussed. (C) 1999 Elsevier Science B. V. All rights reserved.