Wasser-in-Öl-Polymeremulsionen, Verfahren zu ihrer Herstellung und ihre Verwendung

摘要

Water-in-oil polymer emulsions, characterised in that they contain water-soluble polymers having a mean particle size of from 0.1 to 20 mu m emulsified in a continuous oil phase comprising at least 50% by weight of an oil of vegetable or animal origin with the aid of from 0.5 to 15% by weight, based on the total emulsion, of an emulsifier mixture comprising a) from 5 to 95% by weight of a block or graft copolymer of the formula (A-COO)m-B, in which A is a hydrophobic polymer having a molecular weight of > 500 g/mol based on a poly(hydroxycarboxylic acid), B is a bifunctional hydrophilic polymer having a molecular weight of > 500 g/mol based on a polyalkylene oxide, and m is at least 2, and b) from 5 to 95% by weight of another water-in-oil emulsifier having a molecular weight of < 1000 g/mol, and optionally up to 10% by weight, based on the total emulsion, of a wetting agent having an HLB value of greater than 10, process for the preparation of the water-in-oil polymer emulsions, and the use of these emulsions as flocculents for effluent treatment and sewage sludge dewatering and as dewatering and retention agents in papermaking.