FIELD: polymer production.
SUBSTANCE: invention relates to powderlike surface-cross-linked polymerizates absorbing water, aqueous and serous fluids, which can find use as absorbents in sanitary and hygienic objects. Polymerizate is synthesized from (i) 55-99.9% of polymerized ethylenically-unsaturated, acid groups-containing monomers neutralized by at least 25 mol %; (ii) 0-40% of polymerized ethylenically-unsaturated monomers capable of being co-polymerized with monomers (i); (iii) 0.1-5.0% of one or several polymerized cross-linking agents; (iv) 0-30% of water-soluble polymer; provided that amounts of components (i)-(iv) give in sum 100%. Polymerizate is coated with (v) 0.01-5% of organic surface-cross-linking agent (polyols excluded) in the form of aqueous solution; and (vi) 0.001-1.0% of cation in the form of aqueous salt solution to be subjected to additional cross-linking. Preparation procedure comprises mixing all components (i)-(iv) and subjecting resulting mixture to radical polymerization. If necessary, mixture is ground and dried to give powder, which is treated by components (v) and (vi) added simultaneously or separately at vigorous stirring to perform cross-linking of the powder.
EFFECT: enabled production of polymers possessing high capacity under pressure, high retention ability, and high permeability; avoided necessity of using large amounts of solvents and using toxic compounds.
20 cl, 13 tbl, 28 ex
