Crosslinkable polyurea polymers

A prepolymer of formula

• Q—CP—Q (1),
• wherein
• Q is an organic radical that comprises at least one crosslinkable group, and
• CP is a bivalent copolymer fragment consisting of the segments A, B and T, wherein:
• A is a bivalent radical of formula
• —RN—A1—NR′— (2a),
• wherein A1 is the bivalent radical of a polyalkylene glycol or is a linear or branched alkylene radical having from 2 to 24 carbon atoms and each of R and R′ independently of the other is hydrogen or unsubstituted or substituted C1-C6alkyl or, in the case of the amino group that terminates the copolymer fragment, may also be a direct, ring-forming bond;
• T is a bivalent radical of formula
• wherein X is a bivalent aliphatic, cycloaliphatic, aliphatic-cycloaliphatic, aromatic, araliphatic or aliphatic-heterocyclic radical;
• and
• B is a radical of formula A
• —R1N—B1—NR1′— (2b),
• wherein each of R1 and R1′ independently of the other has the meanings given above for R, B1 is a bivalent atiphatic, cycloaliphatic, aliphatic-cycloaliphatic, aromatic or araliphatic hydrocarbon radical that is interrupted by at least one amine group of formula
• R2 is hydrogen, a radical Q mentioned above or a radical of formula
• Q—CP′— (4),
• wherein
• Q is as defined above, and CP′ is a bivalent copolymer fragment independently consisting of at least two of the above-mentioned segments A, B and T;
• with the provisos that in the copolymer fragments CP and CP′ a segment A or B is followed by a segment T in each case;
• that in the copolymer fragments CP and CP′ a segment T is followed by a segment A or B in each case;
• that the radical Q in formulae (1) and (4) is bonded to a segment A or B in each case;
• and that the N atom in formula (3) is bonded to a segment T when R2 is a radical of formula (4).