QUANTITATIVE-ANALYSIS OF POLY(METHYL METHACRYLATE-BUTYL ACRYLATE) COPOLYMER COMPOSITION BY LIQUID-CHROMATOGRAPHY PARTICLE-BEAM MASS-SPECTROMETRY

Current polymer formulations contain mixtures of copolymers to tailor the performance needs. Reversed-phase liquid chromatography is commonl y used to separate polymers according to their chemical composition by adsorption, partition or precipitation mechanisms if retention is not influenced by molecular mass. Liquid chromatography-mass spectrometry (LC-MS) has mainly been used to identify low molecular mass polymers and additives. In this paper, we report on the use of LC-MS for the qu antitative analysis of copolymer composition of several high-molecular -mass polymers by monitoring the low-mass fragments formed by thermal decomposition and electron impact ionization when using a particle bea m interface. The fragment ions produced are proportional to the comono mers present and are quantitatively related to the copolymer compositi on. Area ratio calibration with copolymers of known composition is use d to determine the composition of unknown copolymers of similar struct ure. (C) 1998 Elsevier Science B.V. All rights reserved.