Patent ID: 6653495
Filing Date: 2003-11-25
Classification: C07F,C08G

Abstract:
A process to obtain phosphoric mono- and diester mixtures having the formula:[Rfâ€”CF2â€”(CH2)qâ€”Z]wâ€”P(O)(OH)3âˆ’wâ€ƒâ€ƒ(I) â€ƒHOâ€”[OH(O)Pâ€”Zâ€”(CH2)qâ€”CF2â€”Oâ€”Rfâ€”CF2â€”(CH2)qâ€”Z]vâ€”P(O)(OH)2â€ƒâ€ƒ(II) wherein:w=1-2; v=1-6, q=an integer from 1 to 20, Z=O(C2H4O)pâ€”, O(CH2)nâ€”Oâ€”, O(C3H6O)pâ€” or S(C2H4O)pâ€”, S(C3H6O)pâ€”; n=an integer from 1 to 20; p=an integer from 1 to 5 Rf in formula (II) represents a (per)fluoropolyether chain; Rf in formula (I) is a monofunctional perfluoropolyether chain wherein the chain end group is selected from: CF3Oâ€”, C2F5Oâ€”, C3F7Oâ€”, Cl(C3F6O)â€” or H(C3F6O)â€”; â€ƒsaid process comprising the following steps: a) a monofunctional alcohol having a perfluoropolyoxyalkylene structure of formula: Rfâ€”CF2â€”(CH2)qâ€”ZHâ€ƒâ€ƒ(IA) â€ƒor a &agr;,&ohgr;-diol having a perfluoropolyoxyalkylene structure of formula: â€ƒHZâ€”(CH2)qâ€”CF2â€”Oâ€”Rfâ€”CF2â€”(CH2)qâ€”ZHâ€ƒâ€ƒ(IIA)wherein Rf, Z and q have the above meanings, is added with an amount of water in the range 1-60% by moles, with respect to the alcohol equivalents; b) the admixture obtained in step a) is reacted with phosphoric anhydride, P2O5, added in a single portion or in more portions with a ratio between the alcohol equivalents and the moles of phosphoric anhydride in the range 1.5:1-4:1; c) the compound obtained in step b) is hydrolysed by water or by a diluted solution of hydrochloric acid; d) optionally the organic phase is separated by a solvent immiscible in water and e) the product is recovered from the organic phase.