Antihaft-Prozessmittel und deren Verwendung bei der Herstellung von Wasserabsorbierenden Teilchen

Details

Veröffentlichungs-Nr.

EP2977390

Aktenzeichen

EP15178164

Anmeldetag

24. Juli 2015

Veröffentlichung

21. Juni 2017

Erteilung

21. Juni 2017

Rechtsraum

EP

IPC

C08F20/06C08F120/06C08F220/06C08F2/44

Abstract

The present invention relates to an anti-stick processing aid for use in a process for producing water-absorbing polymers, comprising the 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 polymerizable, ethylenically unsaturated monomers containing acid groups, or salts thereof, or polymerizable, 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 polymerizable, 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, (α5) 0-80% by weight, preferably 2.5-70% by weight and more preferably 5-60% by weight of water, and (α6) 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 the weights of (α1) to (α5) is 100% by weight, (ii) free-radical polymerization with crosslinking to form a water-insoluble, aqueous untreated hydrogel polymer, (iii) drying the hydrogel polymer, (iv) grinding and sieving the hydrogel polymer to size, (v) surface postcrosslinking the ground and sieved hydrogel polymer and (vi) drying and finishing the water-absorbing polymer, wherein the anti-stick processing aid is used alone or in mixtures before and/or in steps (iii)

Anmelder

Firma

Evonik Degussa GmbH

Land

🇩🇪 Deutschland

Fachgebiete