The potential applicability of time-of-flight secondary ion mass spectrometry (ToF SIMS) as an independent quantitative technique has been studied using a more complicated copolymer system: styrene-butadiene copolymer. The complication of this system is that the characteristic SIMS peaks are not unique to each monomer. It has been found that quantitative information can be obtained from the relative SIMS intensities of certain characteristic peaks, i.e. m/z = 63, 89, 103 and 115 for styrene and 53, 67 and 79 for butadiene. In particular, the intensity ratios A/(A + B), where A and B represent, respectively, the above characteristic peaks of styrene and butadiene, have been found to be linearly related to the bulk styrene molar concentration. These results suggest that a sensitivity factor that is constant and independent of the copolymer composition can be defined for these peaks. However, this conclusion cannot be generalized for other SIMS peaks, such as m/z = 77,91 and 105.

Mass spectra of several triglycerides of specific structure or with specific deuterium labeling have been measured with a low resolution mass spectrometer. With saturated triglycerides the abundances of ions characteristic of the component acids, [M-RCO 2 ] § increase with increasing chain length, and [M-RCO2CH2]+ decrease with increasing chain length. Unsaturation in the acyl moiety causes the abundant formation of [RCO-1] +. Structures have been suggested for a number of the main peaks obtained from saturated triglycerides, and high resolution spectra of one triglyceride agree with the postulated structures. The peaks, [RCO+74] § [RCO+115] + and [RCO+128+14n]+, represent structures which contain the glyceryl portion of the triglyceride, since in case of the replacement of its hydrogens with deuteriums, these peaks are shifted accordingly. Evidence which indicates the possibility of determining the location of unsaturation by the interruption of homology of the [RCO+128+14n] § series, brought about by the addition of deuterium to the unsaturated linkages, is introduced.Further evidence is also presented, which indicates that the [M-RCO2CH2] + ions arise from the positions 1 and 3 and, in agreement with earlier studies from other laboratories, it is thus possible to identify the acyl groups attached to the 1 and 2 positions of the glyceryl moiety.

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Deuterium labeled monoacid triglycerides were synthesized and their mass spectra were measured. The spectra provided further support for proposed (1) structures of principal ions, knowledge about the formation of [M-18] +, the interexchange of hydrogen atoms between 2 and the 5, 6 or 7 positions and the expulsion of part of the alkyl chain.