[Preparation and chromatographic characteristics of linear [60] fullerene polysiloxane stationary phase for capillary gas chromatography].

Hydrosilylation of polymethylhydrosiloxane (active hydrogen content was 0.05%) and reactions with allylbromide (or undecenyl bromide), sodium azide and [60] fullerene in their given orders is described. Two kinds of fullerene-containing polysiloxanes were obtained [polymer(3)]. Their [60] fullerene contents were 30 mg (C60-PSO-1) and 60 mg (C60-PSO-2) respectively. These polymers (3) were characterized by FT-IR, 1H-NMR, UV-V, 13C-NMR and used as stationary phase for capillary chromatography. Two fused-silica capillary columns (0.25 mm i.d.) were coated with a 5 g/L solution of polymer (3) in dichloromethane by the static method. The column efficiencies were 3,450 plates/m (C60-PSO-1) and 3,020 plates/m (C60-PSO-2), for naphthalene at 120 degrees C. The average polarities of these columns, represented by the McReynold's Constant, were 79 and 93 respectively. The polarity of C60-PSO-2 was a little higher than that of C60-PSO-1, which was in turn a little higher than that of SE-30(43). These columns showed wide operation temperature range (100-360 degrees C) and outstanding thermostability. It could be used at 360 degrees C with a baseline drift of 30-40 fA. Grob test mixtures eluted on these columns in the ordre of 1,3-butanediol, n-decane, 1-octanol, n-undecane, 2,6-dimethylphenol, n-dodecane, 2,4-dimethylaniline, naphthalene, indicating that the strong pi-pi interaction of [60] fullerene with aromatic moieties played an important role in separation mechanism. The columns exhibited unique selectivity for many organic compounds, such as alkanes, alcohols, ketones and anilines. It can well separate benzene homologues, naphthalene homologues and polyaromatic hydrocarbons(PAHs) due to the pi-pi interaction of three-dimensional pi system of C60 and aromatic hydrocabons. And the columns are especially good for the separation of positional isomers(nonanol, butanediol, nitrotoluene, nitrochlorobenzene, nitroethylbenzene, dinitrobenzene, chlorophenol). The columns also have excellent thermostability and are particularly suitable for the separation of high boiling compounds. For example, polycyclic aromatic hydrocarbons and fatty acid methyl esters are well separated on them.