Permeable super absorbent and preparation method thereof

Highly permeable superabsorbents are prepared by a process comprising polymerizing an aqueous solution of monomers comprising a) at least one ethylenically unsaturated monomer bearing acid groups and optionally in at least partially salt form, b) at least one crosslinking agent, c) at least one initiator, and d) at least one crosslinking agent, d) optionally one or more ethylenically unsaturated monomers copolymerizable with the monomers mentioned in a), and e) optionally one or more water-soluble polymers; drying the resulting polymer, optionally grinding the dried polymer and sifting the ground polymer, optionally subjecting the dried and optionally ground and sifting polymer to surface post-crosslinking, after drying, grinding or sifting, adding an x-ray amorphous aluminum hydroxide powder, and if surface post-crosslinking is carried out, drying the x-ray amorphous aluminum hydroxide powder, optionally grinding and sifting the x-ray amorphous aluminum hydroxide powder, optionally grinding and sifting the x