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Fullerenation of polycarbonate (PC) is achieved by direct reaction of C60 with PC using AlCl3 as catalyst. Stirring a 1,1,2,2-tetrachloroethane solution of C60 and PC in the presence of AlCl3 under nitrogen at 140 °C for 24 h attached C60 to the PC chains, yielding fullerenated PCs (C60-PCs) with a C60 content up to 2.16 wt %. The C60-PCs are soluble in tetrahydrofuran (THF) and chloroform, and IR, UV, and NMR analyses suggest that they possess the molecular structure HxC60(PC)x with x < 1 on the average. The C60-PCs limit strong 532-nm optical pulses more effectively than the parent C60. Light transmission spectra of the C60-PC solutions red-shift with increasing concentration, with their cutoff wavelengths predictably tunable by simply changing their concentrations.

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SummaryThe conditions for reaction of the branched polyfluoroalkylsilane D3CL with silica gel have been examined.From elemental analyses and 29Si NMR spectra it was found that the surface coverage and endcapping of D3CL-coated silica gel (Fluofix | were the same as for ODS packings.The separation behavior of these phases was compared that of a variety of other packings. For polyaromatic compounds and benzene derivatives Fluofix worked in the reversed-phase mode and its retention characteristics were similar to those of C 1 or CN packings. For fluorinated compound the retention characteristics of the phases is similar to those of ODS although with MeOH-water and MeCN-water mobile phases the pressure loss was lower for the fluorinated phases than for ODS.

Capillary electrochromatography using fluorinated‐bonded silica (Fluofix®) under pressurized flow was demonstrated to be applied to the separation of charged compounds and neutral compounds. The reduction and extension of the elution time due to the application of high voltage were demonstrated. The typical variation of elution order of the samples was observed. The reduction of electroosmotic flow mobility (μosm) from the linearity was comparatively observed on the two different effluents when the voltage was applied to the column. The alternations of retention factors of neutral compounds due to applied voltage are observed and the retention mechanisms of the compounds are discussed. With the same electrochromatographic condition and pH of the effluents used, the electroosmotic flow velocity (Vosm) magnitude of the phosphate buffer effluent was higher than the ammonium acetate effluent system. Thus the ammonium acetate might suppress the potentially enhanced negative charge of the stationary phase. ©1999 John Wiley & Sons, Inc. J Micro Sep 11: 590–595, 1999