abstract |
Graft polymers obtainable by the radically initiated polymerisation of (A) monomers or monomer mixture of (a) 1 to 100 wt.% N-vinyl carboxylic acid amides of the formula (I) in which R1, R2 = H and C¿1? to C6 alkyl, (b) 0 to 99 wt.% other monoethylenically unsaturated monomers copolymerisable with the monomers (a), and (c) 0 to 5 wt.% of at least two ethylenically unsaturated monomers with unconjugated double bonds in the molecule; in the presence of (B) polymers containing units of vinyl esters of saturated C1 to C4 carboxylic acids and/or vinyl alcohol units, or mixtures containing these polymers and polymers containing at least 3 alkylene oxide units or polytetrahydrofurane; in the ratio by weight (A) : (B) of (95 to 10) : (5 to 90), possibly followed by the separation of the group (II) from the polymerised monomers (I) of the graft polymer, with the formation of units of the formula (III); process for the production of the graft polymers and use of the graft polymers described above in the production of paper, paperboard and cardboard as a dry and wet strengthening agent, as a retention and dewatering agent and as a promoter in diketene gumming and as a starch cationisation agent, as a dispersant for pigments and as a creping auxiliary in the production of tissue papers. |