QUANTITATIVE SURFACE-ANALYSIS OF STYRENE-BUTADIENE COPOLYMERS USING TIME-OF-FLIGHT SECONDARY-ION MASS-SPECTROMETRY

The potential applicability of time-of-flight secondary ion mass spect rometry (ToF SIMS) as an independent quantitative technique has been s tudied using a more complicated copolymer system: styrene-butadiene co polymer, The complication of this system is that the characteristic SI MS peaks are not unique to each monomer. It has been found that quanti tative information can be obtained from the relative SIMS intensities of certain characteristic peaks, i.e. m/z = 63, 89, 103 and 115 for st yrene and 53, 67 and 79 for butadiene. In particular, the intensity ra tios A/(A + B), where A and B represent, respectively, the above chara cteristic peaks of styrene and butadiene, have been found to be linear ly related to the bulk styrene molar concentration, These results sugg est that a sensitivity factor that is constant and independent of the copolymer composition can be defined for these peaks. However, this co nclusion cannot be generalized for other SIMS peaks, such as m/z = 77, 91 and 105.