摘要 |
A process for the production of stable water-in-oil emulsions of hydrolysed polymers of n-vinyl amide of formula (I) in which R, R<1> = H or C1-C6 alkyl, by the polymerisation of compounds of formula (I) alone or mixed with other ethylenically unsaturated monomers in the presence of polymerisation initiators and emulsifiers in the form of water-in-oil emulsions to form water-in-oil polymer emulsions followed by the hydrolysis of the polymers in the form of the water-in-oil polymer emulsions in the presence of acids or bases and 1 to 30 wt % in relation to the polymers of emulsifiers, in which the emulsifiers used are mixtures of (a) 5 to 95 wt % of a block or graft copolymer of the structure (A-B)m, (A)nB or (B)nA in which A is a hydrophobic homo or copolymer with a degree of polymerisation of at least 3, B is a hydrophilic homo or copolymer with a degree of polymerisation of at least 3, m >/= 1 and n >/= 2, and (b) 5 to 95 wt % of another water-in-oil emulsifier with a molar mass of under 1000 g/mol. The polymer emulsions thus obtained may be used as retention and flocculation agents in paper production, to purify waste water and sludges in purification plants, as a dispersant and protective colloid for drilling muds and as a cement additive. |
申请人 |
BASF AG, 67063 LUDWIGSHAFEN, DE |
发明人 |
HARTMANN, HEINRICH, DR., 67177 LIMBURGERHOF, DE;SCHNEIDER, KARL-HEINRICH, DR., 67271 KLEINKARLBACH, DE;DENZINGER, WALTER, 67346 SPEYER, DE;NILZ, CLAUDIA, DR., 67127 ROEDERSHEIM-GRONAU, DE;MOENCH, DIETMAR, DR., 69469 WEINHEIM, DE |