摘要:
The present invention relates to novel hydrophilic swellable addition polymers comprising improved odor control, a process for their preparation and their use for absorbing aqueous fluids and a process for screening superabsorbents.
摘要:
The present invention relates to novel hydrophilic swellable addition polymers comprising improved odor control, a process for their preparation and their use for absorbing aqueous fluids and a process for screening superabsorbents.
摘要:
Water-swellable hydrophilic polymers are prepared by neutralization of the acidic hydrogel having a degree of neutralization of 0-40 mol % to an ultimate degree of neutralization of 60-85 mol % by mixing with a neutralizing agent in a mincer comprising a system of screw, rotating blade, restricted flow zone and breaker plate, wherein the mincer has a power output of from 1000 to 6000 Wh/m3 the hydrogel passes through a zone having-an energy dissipation density of from 400 to 800 W/1 of mixing volume the average residence time of the hydrogel in the mincer is from 5 to 30 seconds the breaker plate has an open area of from 20 to 40%.
摘要:
Hydrogel particles are produced by a drying step followed sequentially by precomminuting, grinding, separating, and further drying of coarse particles.
摘要:
The invention relates to the use of an apparatus for adding at least one solid or viscous liquid additive, or an additive dispersed in solvent, to a reactor interior of a reactor for preparing crosslinked, finely divided polymers by copolymerizing (a) water-soluble, monoethylenically unsaturated monomers and (b) from 0.001 to 5 mol %, based on the monomers (a), of monomers comprising at least two polymerizable groups, (c) from 0 to 20 mol %, based on the monomers (a), of water-insoluble monoethylenically unsaturated monomers, where the apparatus comprises at least one screw for conveying the at least one additive and the at least one screw ends in an addition orifice substantially flush with the inner wall of the reactor interior.
摘要:
The invention relates to a cross-linked, water-swellable polymer that contains polymerized into it moieties of a) water-soluble, monoethylenically unsaturated monomers, and b) 0.001 to 5 mole % based on the monomers a) of a cross-linking combination, b1) a frist cross-linking agent with at least two (meth)acrylic ester moieties in the molecule and b2) a second cross-linking agent with at least two (meth)allyloxy moieties in the molecule, the molar ratio of b1) to b2) ranging from 0.7:1 to 10:1. The polymer according to the invention has a balanced property profile as regards absorptivity, gel strength, absorption speed and extractable componenents and can be advantageously produced by a continuous method.
摘要:
The present invention relates to a process for modifying hydrophilic polymers by mixing with a modifier, characterized in that the pulverulent polymer and the modifier are introduced continuously into a vertical, cylindrical mixer, mixed at a power of from 1,000 to 5,000 Wh/m3 of powder by means of rotating blades at a blade rate of from 100 to 300 s−1 at a residence time of 1-10 seconds, during which the powder is passed through zones having energy dissipation densities of 300-600 W/l of mixer volume.