Amphiphilic polymer comprising at least 75% of amphiphilic monomers of formula: in which R 1 and R 2 are independently selected from H or a C 1 -C 6 alkyl group; X and Y are independently selected from an oxygen atom, a sulphur atom, a carbonyloxy (- O-) or oxycarbonyl (-O -) group, a urethane group(-OCONH-), and an amide group of formula (-CONR 6 -) or (-NR 6 CO-), wherein R 6 is a hydrogen atom or a C 1 -C 6 alkyl; R 3 and R 4 are independently selected from: a) glycosidic groups, b) zwitterionic residues, c) poly (oxyalkylene) groups of formula -(O(CH 2) x) y -OH, wherein x is comprised between 1 and 6, advantageously x is equal to 2, and y is comprised between 4 and 30, d) alkyl amide groups of formula -(CH 2) n CONR 7 R 8 - or - n NR 7 COR 8 wherein n is comprised between 1 and 4, R 7 and R 8 are selected independently from a hydrogen atom, a C 1 -C 6, alkyl group, a glycosidic group, a zwitterionic residue or a poly(oxyalkylene) group of formula - (O(CH 2) x) y -OH, wherein x and y are as defined above, R 5 is a cyclic (R 5 may contain one or two cycles, saturated or not, particularly of cyclohexane, cyclopentane or aromatic type) or acyclic (linear or branched), saturated or unsaturated (one or more unsaturations), hydrocarbon chain comprising from 5 to 16 carbon atoms, or a hemifluorocarbonated chain of formula C t F 2t+1 (CH 2) m with t comprised between 2 and 10 and m comprised between 2 and 10; the average molar mass by weight of the polymer being comprised between 800 and 100 000. R 1 and R 2 are independently selected from H or a C 1 -C 6 alkyl group; X and Y are independently selected from an oxygen atom, a sulphur atom, a carbonyloxy (- O-) or oxycarbonyl (-O -) group, a urethane group(-OCONH-), and an amide group of formula (-CONR 6 -) or (-NR 6 CO-), wherein R 6 is a hydrogen atom or a C 1 -C 6 alkyl; R 3 and R 4 are independently selected from: a) glycosidic groups, b) zwitterionic residues, c) poly (oxyalkylene) groups of formula -(O(CH 2) x) y -OH, wherein x is comprised between 1 and 6, advantageously x is equal to 2, and y is comprised between 4 and 30, d) alkyl amide groups of formula -(CH 2) n CONR 7 R 8 - or - n NR 7 COR 8 wherein n is comprised between 1 and 4, R 7 and R 8 are selected independently from a hydrogen atom, a C 1 -C 6, alkyl group, a glycosidic group, a zwitterionic residue or a poly(oxyalkylene) group of formula - (O(CH 2) x) y -OH, wherein x and y are as defined above, a) glycosidic groups, b) zwitterionic residues, c) poly (oxyalkylene) groups of formula -(O(CH 2) x) y -OH, wherein x is comprised between 1 and 6, advantageously x is equal to 2, and y is comprised between 4 and 30, d) alkyl amide groups of formula -(CH 2) n CONR 7 R 8 - or - n NR 7 COR 8 wherein n is comprised between 1 and 4, R 7 and R 8 are selected independently from a hydrogen atom, a C 1 -C 6, alkyl group, a glycosidic group, a zwitterionic residue or a poly(oxyalkylene) group of formula - (O(CH 2) x) y -OH, wherein x and y are as defined above, R 5 is a cyclic (R 5 may contain one or two cycles, saturated or not, particularly of cyclohexane, cyclopentane or aromatic type) or acyclic (linear or branched), saturated or unsaturated (one or more unsaturations), hydrocarbon chain comprising from 5 to 16 carbon atoms, or a hemifluorocarbonated chain of formula C t F 2t+1 (CH 2) m with t comprised between 2 and 10 and m comprised between 2 and 10; the average molar mass by weight of the polymer being comprised between 800 and 100 000.