Patent ID: 8865944
Filing Date: 2014-10-21
Classification: C08G

Abstract:
1. A process for the purification of a polyol (per)fluoropolyether derivative [polyol (P)] from a mixture of hydroxyl (per)fluoropolyether derivatives [mixture (M)], said polyol (P) comprising one or more hydroxyl (per)fluoropolyether derivatives [PFPE (OH)] comprising at least one (per)fluoropolyoxyalkylene chain (chain R said mixture (M) comprising said polyol (P) and at least one hydroxyl (per)fluoropolyether derivative [PFPE (OH)], said PFPE(OH) being different from said polyol (P) and comprising at least one (per)fluoropolyoxyalkylene chain (chain R said process comprising the following steps: step 1: reacting said mixture (M) with a ketone, an aldehyde, or a combination thereof so as to yield a corresponding mixture of cyclic ketal/acetal (per)fluoropolyether derivatives [PFPEs (OH) p ] [protected mixture (P)]; step 2: carrying out a molecular distillation of said protected mixture (P) so as to isolate a protected product heavy residue [product (P r )]; step 3: hydrolyzing said product (P r ) so as to yield a deprotected product [product (P d )]; and step 4: carrying out a distillation under reduced pressure of said product (P d ) so as to obtain said polyol (P).