The thermal release products and thermal decomposition products of four food grade polycarbonate (PC) samples were studied by pyrolysis gas chromatography-mass spectrometry (Py-GC/MS). The degradation products of PC samples were detected at difference desorption temperatures and different pyrolysis temperatures. The results showed that there was different between chemical components out-gassing from PC pellets polymerized with different methods; the initial out-gas was produced at 200℃ for all PC samples. Mainly phenol-end groups out-gas was produced. More chemical components produced at higher temperatures. The thermal decomposition mechanism was also explained by analyzing the pyrolysis products. During the pyrolysis process

PC molecular chains can be cleavaged and the fragments were rearranged. The pyrolysis products were mainly phenolic compounds. Whereas some phenolic compounds (for example bisphenue A) were harmful to human beings

The potential phenolic compounds in PC food package materials should be examined

and their special migration should be strictly limited.