Abstract: The thermal decomposition behaviors of benzyl butyl phthalate (BBP) and dibutyl sebacate (DBS) were investigated by pyrolysisgas chromatographymass spectrometry (Py/GCMS) in the temperature range of 500~700 ℃ under a helium atmosphere. The results indicated that the major pyrolysates of BBP were 2butylene, benzyl alcohol, ophthalic anhydride and benzyl benzoate, whereas the major ones for DBS were 2butylene, cyclononanone and sebacic acid. The pyrolysis mechanisms of BBP and DBS were presented on the basis of these pyrolysates as well as the relevant variation of their concentrations. This study provides an important means for optimization of the thermal degradation condition of waste plastics containing different plasticizers.

Key words: benzyl butyl phthalate, dibutyl sebacate, pyrolysis-gas chromatography-mass spectrometry, pyrolysis, pyrolysis mechanism