A biocompatible, biodegradable, macromolecular water-absorbent hybrid material (WAHM), having a three-dimensional configuration with intermolecular covalent bonds and containing free functional groups, said polymer being formed by polymer-polymer intercoupling reaction between a natural water-soluble polymer A or its derivatives having a molecular weight between 20,000 and 300,000 Da, and a synthetic polymer B in an adequate ratio wherein the natural polymer A is selected from amphoteric reactants, partially denatured or chemically modified natural polymer, that dissociates in water to form both anions and cations, and which can undergo polymer-polymer intercoupling reactions, and wherein synthetic polymer B s a linear or branched reactive synthetic copolymer having a molecular weight of 50,000-500,000 Da derived from a vinyl monomer and an ethylenically unsaturated monomer, having a backbone with polymeric subunits covalently bonded to the polymer backbone, the subunits comprising ones with non-reactive and others with reactive chemical functional groups.
