ANALYSIS OF MACROCYCLIC POLYSTYRENES .2. MASS-SPECTROMETRIC INVESTIGATIONS

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is shown to be a new and powerful technique for the analysis of macroc yclic polystyrenes and their linear precursors. The oligomer distribut ions for samples of different molar masses are obtained and the end gr oups of the linear precursors are identified. The chemical structure o f the cyclization products is determined and it is shown that in the M ALDI process the labile benzylic chlorine substituent at the macrocycl e is abstracted, to yield a double bond. It is shown that MALDI mass s pectrometry alone does not provide full information on the composition of the reaction products. The chemical structure of the macrocycles a nd the linear byproducts can be determined by chromatographic separati on and subsequent MALDI analysis.