abstract |
PCT No. PCT/EP96/02991 Sec. 371 Date Jan. 21, 1998 Sec. 102(e) Date Jan. 21, 1998 PCT Filed Jul. 9, 1996 PCT Pub. No. WO97/04014 PCT Pub. Date Feb. 6, 1997Graft polymers are obtainable by free radical polymerization of (A) monomers or monomer mixtures comprising (a) from 1 to 100% by weight of N-vinylcarboxamides of the formula where R1 and R2 are each H or C1-C6-alkyl, (b) from 0 to 99% by weight of other monoethylenically unsaturated monomers copolymerizable with the monomers (a) and (c) from 0 to 5% by weight of monomers having at least two ethylenically unsaturated, nonconjugated double bonds in the molecule, in the presence of (B) polymers which contain units of vinyl esters of saturated C1-C4-carboxylic acids and/or vinyl alcohol units, or of mixtures which contain these polymers and polymers having at least 3 alkylene oxide units or polytetrahydrofuran, in a weight ratio (A):(B) of from 95:5 to 10:90 and, if required, subsequent elimination of the group from the polymerized monomers (I) of the graft polymer with formation of units of the formula and the graft polymers described above are used in the production of paper, board and cardboard as dry and wet strength agents, as retention and drainage aids and as promoters in diketene sizing and as starch cationization agents, as dispersants for pigments and as creping assistants in the production of tissue papers. |