Patent ID: 8552093

Claim:
A method comprising adding at least one polymer or a salt thereof as an admixture to a hydraulic binder, said polymer being of formula (I) Z—P—Z′ (I) in which Z is an end of a chain and represents a hydrogen atom, a hypophosphite group or a phosphonate group; Z′ is an end of a chain and represents a hypophosphite group or a phosphonate group; P represents a component comprising at least one moiety of formula (II) in which R1, R2 and R3 independently represent a hydrogen atom, a linear or branched C 1 to C 20 alkyl radical, or a —(CH 2 ) p —COOR radical or an ionized form thereof where p is equal to 0 or 1, and R is a hydrogen atom or R is a C 1 to C 6 alkyl radical; R4 represents a hydrogen atom, a monovalent, divalent or trivalent ion, or a quaternary ammonium radical; and optionally comprising at least one moiety of formula (III) R5, R6 and R7 independently represent a hydrogen atom, a linear or branched C 1 to C 20 alkyl radical, or a —(CH2) n —(C═O) m —W—(R8-O) q —R9 radical; R8 represents a linear or branched C 2 to C 20 alkyl radical; R9 represents a hydrogen atom, or a linear or branched C 1 to C 20 alkyl radical; W represents an oxygen or nitrogen atom; n is an integer comprised from 0 to 2; m is an integer equal to 0 or 1; q is an integer comprised from 0 to 200; and in which the degree of polymerisation is comprised from 5 to 200, wherein said polymer or a salt thereof is used as a blocking agent for blocking the setting of the hydraulic binder.