Abstract: Methods and systems for producing superabsorbent polymer particles for use in agricultural applications are disclosed. A monomer is graft polymerized onto a starch to form a starch graft copolymer. The moisture content of the starch graft copolymer is reduced through the use of an extruder.
Type:
Grant
Filed:
January 25, 2007
Date of Patent:
September 22, 2009
Assignee:
Absorbent Technologies, Inc.
Inventors:
Milan H. Savich, Rodney L. Forni, William Chambers
Abstract: The present invention provides: a novel water-absorbing agent, which exhibits an excellent absorption capacity under a load (AAP), gel layer liquid permeation rate under a load (FRUP), saline flow conductivity (SFC), and shape-maintaining property and ball burst strength (BBS) of a swollen water-absorbing agent aggregate, and excellent persistency of these effects for a long time. The water-absorbing agent, which comprises a polymer obtained by a process including the steps of polymerizing and then crosslinking a monomer including acrylic acid and/or a salt thereof, with the water-absorbing agent being characterized by: (1) exhibiting a free swelling capacity of not less than 23 g/g (GV), a gel deformation of not more than 12.5 cm under a short-time load (0.5 hrPT), and a gel deformation deterioration of not more than 3.
Abstract: A pressure-sensitive adhesive material made of an elastic mixture comprising a continuous phase formed from a physically cross-linked solid rubber such as a styrene-olefin-styrene block copolymer, for example a styrene-isoprene-styrene block copolymer, and a compatible liquid rubber, such as a liquid styrene-isoprene, and a discontinuous phase substantially comprised of one or more “swellable polymers”, absorbents that are swellable in water. Additives such as polybutenes, polyisobutylene, mineral oil, stabilizers and other rubbers, may be present. Water soluble polymers may be added to the swellable absorbents to form part of the discontinuous phase. The pressure-sensitive adhesives the advantage over the prior are that they avoid the need to include materials known to irritate skin and mucous membranes. In particular, prior art compositions have needed to include substantial quantities of tackifying resins, which could cause problems particularly in wound dressings.