LC-multistage mass spectrometry for the characterization of poly(butylene adipate-co-butylene terephthalate) copolyester.

A comprehensive study using liquid chromatography electrospray ionization multistage mass spectrometry (LC-ESI MS(n)) was performed to get detailed structural information on poly(butylene adipate-co-butylene terephthalate) co-polyester and its product of partial degradation. LC-MS and LC-MS(n) identified the existence of cyclic structures in the original samples that disappear completely during the degradation. The occurrence of methanol transesterification in the degradation process was confirmed. MS(2) on the first (13)C isotope peak helped to determine the elemental composition of the fragments and facilitated end group determination. The method can be used to provide an alternative for high mass accuracy MS(2) experiments. Sequence information was also revealed for certain copolymeric structures. © American Society for Mass Spectrometry, 2011