Study of synthetic aliphatic copolyamides by time-of-f light matrix assisted laser desorption/ionization mass spectrometry

摘要

Synthetic copolyamides based on aliphatic diamines(1,3-propanediamine and 1,4-butanediamine)and dichlorides of aliphatic carboxylic acids(adipic and sebacic acid dichlorides)were investigated using time-of-fiight matrix assisted laser desorption/ionization mass spectrometry.Their mass spectra showed peaks for cationized(Na~+and K~+)and proto-nated(less intense peaks)oligomers with NH2-NH2,NH2-COOH,or COOH-COOH end groups.No cyclic oligomers were detected in the samples.The compositions of oligomers were determined,and the relative reactivities of homologous comonomers in polycondensation were estimated.