Abstract:
PROBLEM TO BE SOLVED: To simplify a production method for a material usable as a radical crosslinking agent for a high-absorbent material.SOLUTION: A method for producing a crosslinked hydrogel is provided, in which a polyalcohol A is reacted with an ethylenically unsaturated carboxylic acid B in the presence of an esterification catalyst C, a polymerization inhibitor D, and optionally a solvent E which forms an azeotrope with water under the formation of an ester F. Optionally, at least a part of water produced is removed from a reaction mixture, optionally the reaction mixture is neutralized, and the solvent E is removed by distillation, and/or stripped using a gas which is inert under reaction conditions. The reaction mixture from one of the steps, optionally an additional monoethylenically unsaturated compound N, and optionally a copolymerizable hydrophilic monomer M are polymerized in the presence of a radical initiator K and optionally a graft base L. Optionally, the reaction mixture obtained is subjected to post crosslinking, drying, pulverization, and/or screening.
Abstract:
The invention relates to a method for producing water-absorbing polymer particles by suspension polymerization and thermal surface post-curing. The base polymer obtained by suspension polymerization has a centrifuge retention capacity of at least 37 g/g and the thermal surface post-curing is carried out at between 100 -190°C.
Abstract:
The invention relates to a method for producing deodorizing water-absorbing polymer particles based on ethylenically unsaturated, acid group-carrying monomers, the polymer particles being coated with a chelating agent and a tannin.
Abstract:
The invention relates to a method for producing water-absorbing polymer particles, wherein at least one aliphatic aldehyde or the conversion product thereof has an aliphatic alcohol, an aliphatic amine, ammonia, a hypophosphite, or a phosphite added thereto.
Abstract:
The present invention relates to a water-absorbing material obtainable by a process comprising the steps of A) treating a particulate, non-surface-crosslinked, water-absorbing polymer with a mixture comprising an aqueous solvent and at least one salt of a transition metal and B) irradiating the polymer treated according to A) with UV radiation, to a process for its production and to articles comprising the water-absorbing material.
Abstract:
Superabsorbents containing a compound of formula (I) where M represents a hydrogen atom, an ammonium ion, a monovalent metal ion or one equivalent of a divalent metal ion of groups 1, 2, 8, 9, 10, 12 or 14 of the periodic table; R1 represents OH or NR4R5, where R4 and R5 independently represent H or C1-C6-alkyl; R2 represents H or an alkyl, alkenyl, cycloalkyl or aryl group which optionally has 1, 2 or 3 substituents selected independently from C1-C6-alkyl, OH, O-C1-C6-alkyl, halogen and CF3; and R3 represents COOM, SO3M, COR4, CONR4R5 or COOR4, where M, R4 and R5 are each as defined above, or, when R2 represents aryl which is optionally substituted as indicated above, also represents H, salts thereof or mixtures of such compounds and/or salts thereof display improved stability to discoloration in storage under elevated temperatures or elevated relative humidity.
Abstract:
The invention relates to deodorizing mixtures, containing water-absorbing polymer particles and spherical activated carbon, for use in incontinence articles.