Electrospray Ionization Mass Spectrometry of Poly(styrene)

Abstract

The effect of cone voltage on the polymer mass distribution of non-polar poly(styrene) samples has been investigated using electrospray ionization. It was found that relatively high cone voltages (120 V) were required to ionize non-polar polymers. At lower cone voltages (30–60 V), cluster ions, e.g. [M+2cat]2+ and [2M+cat]4, were observed. Singly-charged species predominated only at high cone voltages, but no fragmentation of the oligomer ions has been seen. The molecular mass distributions obtained by electrospray ionization have been compared with those obtained by size-exclusion chromatography and the agreement (generally within 10%) has been shown to be cone-voltage dependent.