Structural analysis of synthetic homo- and copolyesters by electrospray ionization on a Fourier transform ion cyclotron resonance mass spectrometer

The molecular structure of a series of homo- and copolyesters was studied u sing sustained off-resonance irradiation collisionally activation dissociat ion on a Fourier transform ion cyclotron resonance mass spectrometer. Elect rospray ionization was used as an ionization technique. The most important fragmentation pathways of the homopolyesters poly(dipropoxylated bisphenol- A/adipic acid) and poly(dipropoxylated bisphenol-A/isophthalic acid) were s tudied, Six different dissociation mechanisms were observed which are very similar to the mechanisms found to occur during pyrolysis of these compound s. Four of these mechanisms are a result of cleavages of the ester bond and the others are due to cleavages of the ether bond or bisphenol-il unit. So me of the fragments expected are not present in the spectrum, indicating th at each fragment has a specific sodium affinity. Sequence-specific fragment s of two of the three copolyester sequences that theoretically can exist we re experimentally observed, Fragments that originate from the third sequenc e are not unique and can also be formed from other sequences. Therefore, it was not possible to determine the presence of the third sequence. Copyrigh t (C) 2000 John Wiley & Sons, Ltd.