Direct pyrolysis mass spectra of poly(p-xylylene)(PPX) and poly(hydroxybutyrate)(PHB)

Abstract

Direct pyrolysis mass spectrometry (DPMS) has been applied to poly(p-xylylene)(PPX) and poly(hydroxybutyrate)(PHB) samples. The validity of a mathematical model for pyrolytic behaviour was tested using PPX and then applied to PHB. Simple cleavage at an ester bond has been shown to be the most probable process in the latter. Examination of a random copolymer of PHB with 20% hydroxyvalerate (HV) shows that the latter behaves pyrolytically in a similar manner to PHB itself. DPMS can be used to detect very low levels of a second monomer in a polymer sample.