3B-O1-0900 PDF
Attempt to obtain good mass spectra for synthetic polymers difficult to be ionized
Matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) mass spectrometry (MS) for the analysis of polymers has dramatically increased the mass range of intact polymers. MALDI-MS and ESI-MS demonstrate structural details of synthetic polymers: average molar masses, the structures of monomer repeat units, and the masses of chain end groups, etc. However, it is generally difficult to ionize the polymers with high-molecular weight, i.e. those exceeding 10,000 Da, even if MALDI is used. Thus, structural details of the polymers are not easily obtained from mass spectra. Here, the techniques to obtain good mass spectra of high-molecular weight polymers are discussed in terms of chemical derivatization, surface-assisted laser desorption/ionization (SALDI), degradation by laser or ultrasonic irradiation and LC separation.