Patent ID: 9145471
Filing Date: 2015-09-29
Classification: C08G,Y02P

Abstract:
1. A process for increasing the content of bifunctional species in mixtures of non functional, mono- and bifunctional (per)fluoropolyethers which comprises the following steps: (a) adsorbing a mixture (M) of non functional, mono- and bifunctional (per)fluoropolyethers having a first average functionality (F1) onto an adsorbing stationary phase; (b) desorbing mixture (M) with a supercritical fluid to recover a (per)fluoropolyether mixture (M′) having a second average functionality (F2) lower than functionality (F1); (c) desorbing the remaining mixture (M) with the supercritical fluid in admixture with a polar solvent to recover a (per)fluoropolyether mixture (M″) having a third average functionality (F3) higher than functionality (F1).