摘要 |
Separation process of bifunctional macromolecules having hydroxylic termination from non functional and/or monofunctional macromolecules having hydroxylic termination contained in admixture in perfluoropolyoxyalkylenes (I) comprising the following phases: addition of the macromer (I) to a suspension of stationary phase in polar solvent, said stationary phase being formed by a compound containing sites and/or active groups, capable of establishing bonds or interactions of polar type, or hydrogen bonds, with the hydroxylic terminals of the perfluoropolyoxyalkylenes contained in the mixture of formula (I), the macromer/stationary phase ratio ranging from 2/3 to 1/1 w/w; solvent/(stationary phase+macromer) ratio ranging from 0.8/1 to 1.5/1 v/w; evaporation of the solvent, until obtainment of an incoherent and dry powder; first extraction with low polarity fluorinated solvent and separation of the phases by filtering; second extraction of the stationary phase with polar hydrogenated solvent, and separation of the phases by filtering; the macromer fraction having high bifunctionality degree being obtained by concentration of the liquid phase after second extraction, i.e. after removal of the solvent.
|