The invention relates to a process for producing a water-absorbing polymer composition, comprising the process steps of (i) mixing (α1) 0.1 to 99.999% by weight, preferably 20 to 98.99% by weight and more preferably 30 to 98.95% by weight of polymerized, ethylenically unsaturated monomers containing acid groups or salts thereof or polymerized, ethylenically unsaturated monomers including a protonated or quaternized nitrogen, or mixtures thereof, particular preference being given to mixtures including at least ethylenically unsaturated monomers containing acid groups, preferably acrylic acid, (α2) 0 to 70% by weight, preferably 1 to 60% by weight and more preferably 1 to 40% by weight of polymerized, ethylenically unsaturated monomers copolymerizable with (α1), (α3) 0.001 to 10% by weight, preferably 0.01 to 7% by weight and more preferably 0.05 to 5% by weight of one or more crosslinkers, (α4) 0 to 30% by weight, preferably 1 to 20% by weight and more preferably 5 to 10% by weight of water-soluble polymers, and (α5) 0 to 20% by weight, preferably 0.01 to 7% by weight and more preferably 0.05 to 5% by weight of one or more assistants, where the sum of their weights (α1) to (α5) is 100% by weight, (ii) free-radical polymerization with crosslinking to form a water-insoluble aqueous untreated hydrogel polymer, (iii) comminuting and drying the hydrogel polymer, (iv) optionally grinding and sieving the water-absorbing polymer, (v) surface postcrosslinking the ground hydrogel polymer and (vi) drying and finishing the water-absorbing polymer, wherein blowing agents having a particle size of 100 μm to 900 μm are added to the aqueous monomer solution prior to the addition of the initiator and the start of the free-radical polymerization.本發明係關於一種用於製造吸水性聚合物組合物的方法，包含以下處理步驟：(i)混合(α1)0.1至99.999重量%，較佳20至98.99重量%，更佳30至98.95重量%的含酸性基團的聚合烯鍵式不飽和單體或其鹽類、或包括一質子化或四級化(quarternized)氮的聚合烯鍵式不飽和單體、或其混合物，尤以包括含酸性基團的至少烯鍵式不飽和單體，較佳丙烯酸，的混合物為較佳，(α2)0至70重量%，較佳1至60重量%，更佳1至40重量%的可與(α1)共聚合的聚合烯鍵式不飽和單體
