Aqueous dispersion of polymer based on multi-structured polymer particles (at least 3 different polymer phases), characterized in that said particle comprises: - a polymer phase as core, based on a polymer P1 derived from the emulsion polymerization of a monomer composition M1, with P1 having a glass transition temperature Tg1, calculated according to Fox, ranging from 60 to 120°C and preferably from 60 to 100°C, - a second polymer phase enveloping said core, based on a polymer P2 derived from the emulsion polymerization of a monomer composition M2, with P2 having a glass transition temperature Tg2, calculated according to Fox, ranging from -60 to 40°C and preferably from -30 to 30°C, - a third outer polymer phase (or shell) enveloping said phase P2, based on a polymer P3 derived from the emulsion polymerization of a monomer composition M3, with P3 having a glass transition temperature Tg3, calculated according to Fox, ranging from Tg2 - 5°C to Tg2 + 5°C and Tg3 preferably being equal to Tg2 ± 2°C, and a number-average molecular mass Mn, measured by size exclusion chromatography with polystyrene calibration, not exceeding 150 000, preferably ranging from 1000 to 150 000, with the weight contents relative to the total weight of polymer P1 + P2 + P3 being for: - P1 from 5% to 50% - P2 from 40% to 85%, preferably from 45% to 80% - P3 from 5% to 25%, preferably from 10% to 20% and the sum of said weight contents (P1 + P2 + P3) being equal to 100% and in that said composition M3 from which P3 is derived and optionally said composition M2 from which P2 is derived comprise at least one ethylenically unsaturated monomer bearing, in addition to its ethylenic unsaturation, at least one functional group X selected from: acetoacetoxy, alkoxysilane, carboxy/anhydride, hydroxy, amine, epoxy (or oxirane), phosphate, phosphonate, phosphinate, sulfate, sulfonate, amide, imidazole, cyclic carbonate, ureido, and preferably from: acetoacetoxy, carboxy/anhydride, hydroxy, amine, epoxy (or oxirane), phosphate, phosphonate, phosphinate, sulfate, sulfonate, amide, imidazole, cyclic carbonate or ureido. - a polymer phase as core, based on a polymer P1 derived from the emulsion polymerization of a monomer composition M1, with P1 having a glass transition temperature Tg1, calculated according to Fox, ranging from 60 to 120°C and preferably from 60 to 100°C, - a second polymer phase enveloping said core, based on a polymer P2 derived from the emulsion polymerization of a monomer composition M2, with P2 having a glass transition temperature Tg2, calculated according to Fox, ranging from -60 to 40°C and preferably from -30 to 30°C, - a third outer polymer phase (or shell) enveloping said phase P2, based on a polymer P3 derived from the emulsion polymerization of a monomer composition M3, with P3 having a glass transition temperature Tg3, calculated according to Fox, ranging from Tg2 - 5°C to Tg2 + 5°C and Tg3 preferably being equal to Tg2 ± 2°C, and a number-average molecular mass Mn, measured by size exclusion chromatography with polystyrene calibration, not exceeding 150 000, preferably ranging from 1000 to 150 000, - P1 from 5% to 50% - P2 from 40% to 85%, preferably from 45% to 80% - P3 from 5% to 25%, preferably from 10% to 20% and the sum of said weight contents (P1 + P2 + P3) being equal to 100% and in that said composition M3 from which P3 is derived and optionally said composition M2 from which P2 is derived comprise at least one ethylenically unsaturated monomer bearing, in addition to its ethylenic unsaturation, at least one functional group X selected from: acetoacetoxy, alkoxysilane, carboxy/anhydride, hydroxy, amine, epoxy (or oxirane), phosphate, phosphonate, phosphinate, sulfate, sulfonate, amide, imidazole, cyclic carbonate, ureido, and preferably from: acetoacetoxy, carboxy/anhydride, hydroxy, amine, epoxy (or oxirane), phosphate, phosphonate, phosphinate, sulfate, sulfonate, amide, imidazole, cyclic carbonate or ureido.