Abstract:
The present invention relates to a process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution in a surrounding heated gas phase and flowing the gas cocurrent through the polymerization chamber, which comprises thermal postcrosslinking in the presence of steam.
Abstract:
A process for producing water-absorbing polymer particles, wherein at least one inorganic phosphoric acid and/or salt thereof and at least one organic 2-hydroxy acid and/or salt thereof is added, where the phosphorus in the inorganic phosphoric acid has an oxidation number of less than +V and the organic 2-hydroxy acid does not have any ethylenically unsaturated groups, and also the water-absorbing polymer particles obtainable by the process according to the invention.
Abstract:
The present invention relates to a water absorbing material obtainable by a process comprising the steps of bringing particles of a non surface-crosslinked water-absorbing polymer in contact with a) at least one post-crosslinker, b) 0.1-1.0 wt. % of at least one water-insoluble metal phosphate, based on the non surface-crosslinked water-absorbing polymer, and at least one further ingredient selected from c) at least one Nitrogen-containing water-soluble polymer of which the Nitrogen can be protonated, and d) at least one hydrophobic polymer and heat-treating the particles thus obtained at a temperature in the range from 120° C. to 300° C. and a method for the production thereof.
Abstract:
The present invention relates to a water absorbing material obtainable by a process comprising the steps of bringing particles of a non surface-crosslinked water-absorbing polymer in contact with a) at least one postcrosslinker, b) 10-1000 ppm, based on the non surface-crosslinked water-absorbing polymer, of at least one Nitrogen-containing water-soluble polymer of which the Nitrogen can be protonated, and c) at least one hydrophobic polymer and heat-treating the particles thus obtained at a temperature in the range from 120° C. to 300° C. and a method for the production thereof.
Abstract:
The present invention relates to a process for producing a water-absorbing material comprising the step of spray-coating water-absorbing polymeric particles with at least one non-reactive coating agent in a continuous process in a fluidized bed reactor in the range from 0° C. to 150° C., with the proviso that the non-reactive coating agents do not comprise an elastic film-forming polymer, the water-absorbing material obtainable by this process, the use of the water-absorbing material in hygiene articles and packaging material and hygiene articles comprising this material.
Abstract:
Use of colored polymer systems having a color which is changeable in the case of a strain for indicating the stress state of hygiene or medical articles adjacent to the body.
Abstract:
The present invention relates to a water-absorbing material obtainable by a process comprising the steps of a) spray-coating water-absorbing polymeric particles with an elastic film-forming polymer in a fluidized bed reactor in the range from 00 C. to 500 C and b) heat-treating the coated particles at a temperature above 500 C. and also to a process for its production.
Abstract:
Disclosed is a process for postcrosslinking a water absorbing polymer by the polymer being treated with at least one postcrosslinker and postcrosslinked and dried during or after the treatment by raising the temperature, the at least one postcrosslinker being a cyclic carbamate or a cyclic urea, wherein the cyclic carbamate or the cyclic urea was obtained by reacting respectively an aminoalcohol or a diamine with a cyclic carbonate.
Abstract:
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.