Chromatographic process of separation or enrichment of perfluoropolyoxyalkylene mixture

摘要

Process for sepg. from one another, one or more of the non-, mono- and bi-functional species of macromolecules constituting a perfluoropolyoxyalkylene of formula X-O-Rf-Y (I) comprises subjecting (I) to a column chromatographic treatment according to modalities which comprise, in the order (a) preparing a stationary phase by treating a solid phase, which is composed of a cpd. contg. active sites and/or gps. capable of forming bonds or interactions of the polar type, or H bonds with the OH end gps. of (I) with a non-polar fluorinated solvent (II), (b) absorption of (I) by the stationary phase, carried out by feeding to the column head a (I) soln. in the min. amt. of the (II), (c) elution of the (I) so adsorbed by feeding (II) to the column head, (d) further subsequent elution of the (I) by feeding to the column head, a mixt. composed of (II) and a polar solvent in vol. ratio of 9/1-1/1, (e) washing the column contg. the stationary phase with a pure non-polar solvent, and opt. (f) recharging the stationary phase with a further (I) sample to be subjected to chromatographic analysis according to steps (c) to (f). In (I), Rf = a perfluoropolyoxyalkylene (PFOA) chain having an Mn of 500-10000 and comprising PFOA unit(s) of formula (CF2CF2O), (CF2O), (CF2CF2CF2O) statistically arranged along the chain, X, Y = functional gp. of formula -CF2-CH2O(CH2CH2O)sH, -CF2-CF2-CH2O(CH2CH2O)sH, -CF2CH2NH2, or non-functional gps. of formula -CF2CF2CF3, -CF2CF2Cl, -CF2CF3, -CF2Cl, -CF3, -CFCl2, -CF2Br or -CFBr2 and s = 0-2, with X and Y in parts of such macromolecules being -CF2-CH2O(CH2CH2O)sH and/or -CF2CF2CH2O(CH2CH2O)sH and/or -CF2CH2NH2 gps.