摘要

Mass spectrometry is a powerful tool for end group determination. Several ionization techniques are available. Unfortunately for labile-end-group-containing polymers and especially for polystyrene, cleavage of the end group may easily occur upon ionization. An alternative ionization method suitable for non-polar polymers is atmospheric pressure photo-ionization (APPI). High-energy photons can eliminate an electron out of certain compounds forming radical cations. Additionally in the presence of halogenated solvents the released electrons can be captured forming chloride ions. Hence, adducts can be seen in the negative mode as well. In order to analyze the end groups in PS prepared by ATRP APPI was applied to minimize elimination. For all PS-C1 samples the existence of Cl-end groups as sole end group could be shown. For PS-Br partial preservation of the end groups were obtained. Hence, APPI-ToF-MS in negative mode has been proven a suitable tool to analyze polymers with labile end groups.

  • 出版日期2017-5