Agent for obtaining a stable aqueous composition comprising a polymer constituted of:at least one A monomer of acrylic acid and/or methacrylic acid and/or any of their salts,at least one B monomer of alkyl acrylate and/or methacrylate, andat least one C monomer corresponding to the following formula (I):T-[(EO)n(PO)n′(BO)n″]-Z (I) in which: T represents one end enabling the co-polymerization of the C monomer,[(EO)n(PO)n′(BO)n″] represents a polyalkoxylated chain constituted of alkoxylated units, distributed into blocks, alternatively or statistically, chosen from among EO ethoxylated units, PO propoxylated units and BO butoxylated units, representing, independently from each other, 0 or a whole number between 1 and 150, the sum of n, -n′ and n″ not being null, andZ represents a fatty chain, linear or branched, of at least 16 carbon atoms,at least one crosslinked monomer D.
