Matrix-assisted laser desorption ionization time of flight mass spectrometry analysis of living cationic polymerization of vinyl ethers. I. Optimization of measurement conditions for poly(isobutyl vinyl ether)

Matrix-assisted laser desorption ionization time of flight mass spectrometr y (MALDI-TOF-MS) was utilized for the analysis of polymers obtained by the living cationic polymerization of isobutyl vinyl ether (IBVE) with the HCl- VE adduct/SnCl4/n-Bu4NCl initiating system in CH2Cl2 at -78 degreesC. Under optimized analysis conditions, well-resolved spectra were obtained for sam ples with number-average molecular weights of less than or equal to 10(4) w ith the use of 1,8-dihydroxy-9(10H)-anthracenone (dithranol) as a matrix an d sodium trifluoroacetate as an added salt. The MS spectra showed only one series of peaks separated exactly by the mass of the IBVE. The observed mas s of each peak was in good agreement with the theoretical one, which posses ses one initiator fragment at the alpha end and one methoxy group originate d from quenching with methanol at the omega end. Thus, detailed end group a nalysis is possible for poly(VE). (C) 2000 John Wiley & Sons, Inc.