Applications of gas chromatography in the paint & allied industries Part I: raw materials

Solvents by their very nature are volatile substances and therefore eminently suitable for analysis by GC. The separation of low‐molecular‐weight hydrocarbons on a highly‐polar stationary phase, which consisted of mixed bis‐lactams, was reported by Ravey (157). The packing was claimed to be stable up to 80°C, thus permitting some degree of temperature programming to be used, so that the molecular‐weight range of the samples examined in one analysis could be increased. The specific retention volumes and retention indices at 45°C for a total of 49 normal, branched or halogenated hydrocarbons were measured by Zielinski and Martine (211) for a series of seven stationary phases of similar chain length. These consisted of n‐heptadecance, l‐ hexadecylchloride, l‐hevadeceen,l‐hexadecylbromide, l‐hexadecyliodide, di‐n‐octyl ether and di‐n‐octyl thioether and the procedures described were used in the choice and classification of the stationary phases for GC. Separation of the alkenenaphthene fraction of white spirit was carried out by Leont'eva et al. (120) on a column coated with squalane and operated at 100°C. The carrier gas was helium and fifty three separate peaks were identified and quantified using a flameionisation detector (FID). A squalane capillary column was used by Kumar et al. (115) to identify the hydrocarbon components of a petroleum naphtha fraction (boiling range 40 to 150°C). The analysis was performed under isothermal conditions.