High-mass-resolution ToF-SIMS study of chlorine-containing polymers

A series of seven chlorine-containing polymers with widely ranging structures have been studied by time-of-flight secondary ion mass spectrometry (ToF-SIMS) at high mass resolution. The prototypical positive ion spectrum of poly(vinyl chloride) has been analysed in detail to identify unambiguously all the components at each nominal mass up to m/z 130. For other polymers based on variously Cl-substituted aliphatic hydrocarbons, the same Cl-containing ions are observed but their relative intensities are different and characteristic. The relative intensities of common fragments containing one or two chlorine atoms in both positive ion spectra (RCl2+/RCl+) and negative ion spectra (Cl-2(-)/Cl-) have been compared quantitatively with the bulk atomic chlorine concentration. These two ratios also show a remarkable correlation across the polymer series. An ion formation mechanism is proposed to explain the observed correlations. Copyright (C) 2002 John Wiley Sons, Ltd.