| abstract |
Compounds having the following formula: n nwherein: n A and A 1 , equal or different, are respectively H or an aromatic end group as defined below; optionally said aromatic group being substituted; n is an integer different from zero, such that the number average molecular weight of the compound of formula (I) is in the range 1,800-50,000, T is the bivalent group —Y—CH 2 —CFW 1 —O—Rf—CFW 2 —CH 2 —Y—wherein: Y=O, S; n W 1 and W 2 , equal or different, are F, CF 3 ; Rf is a (per) fluoropolyoxyalkylene chain formed of one or more repeating units, statistically distributed along the chain; |