Patent ID: 8829135

Claim:
A process for continuously producing water-absorbing polymer particles, comprising the polymerization of a monomer solution or suspension comprising a) acrylic acid which may be at least partly neutralized, b) at least one crosslinker, c) at least one initiator, d) optionally one or more ethylenically unsaturated monomer copolymerizable with acrylic acid, e) optionally one or more water-soluble polymer, and f) water, to give a polymer gel, drying of the resulting polymer gel, comminuting the dried polymer gel to give polymer particles, and classifying the resulting polymer particles, wherein the acrylic acid a) being polymerized is supplied continuously and the acrylic acid a) being polymerized and supplied continuously has a purity of less than 99.8% by weight and the purity of the acrylic acid a) being polymerized and supplied continuously varies by less than 2% by weight within 24 hours.