Polymeric polycarboxylic acid crosslinked cellulosic fibers
AssigneeWeyerhaeuser Company
InventorsJohn A. Westland, Richard A. Jewell, Amar N. Neogi
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Abstract
Cellulosic fibers intrafiber crosslinked with a polymeric polycarboxylic acid crosslinking agent are disclosed. In one embodiment, the polymeric polycarboxylic acid is polyacrylic acid and, in another embodiment, the polycarboxylic acid is polymaleic acid. Methods for forming cellulosic fibers having stable intrafiber crosslinks and for forming crosslinked cellulosic fibers having low knot level are also disclosed.
Claims14
Individualized, chemically crosslinked cellulosic fibers comprising cellulosic fibers intrafiber crosslinked with a polymaleic acid crosslinking agent, wherein the polymaleic acid crosslinking agent is a polymer selected from the group consisting of a polymaleic acid polymer, a copolymer of maleic acid and a monoalkyl substituted phosphinate, a copolymer of maleic acid and a monoalkyl substituted phosphonate, a copolymer of maleic acid and a comonomer, and mixtures thereof, wherein the comonomer is selected from the group consisting of vinyl acetate, methyl vinyl ether, and itaconic acid.
Individualized, chemically crosslinked cellulosic fibers comprising cellulosic fibers intrafiber crosslinked with a polymaleic acid crosslinking agent, wherein the crosslinked fibers comprise stable intrafiber crosslinks and have a reverted density increase of less than about 20 percent, and wherein the polymaleic acid crosslinking agent is a polymer selected from the group consisting of a polymaleic acid polymer, a copolymer of maleic acid and a monoalkyl substituted phosphinate, a copolymer of maleic acid and a monoalkyl substituted phosphonate, a copolymer of maleic acid and a comonomer, and mixtures thereof, wherein the comonomer is selected from the group consisting of vinyl acetate, methyl vinyl ether, and itaconic acid.
A method for forming individualized, chemically intrafiber crosslinked cellulosic fibers comprising the steps of:
- applying a polymaleic acid crosslinking agent to a mat of cellulosic fibers, wherein the crosslinking agent is a polymer selected from the group consisting of a polymaleic acid polymer, a copolymer of maleic acid and a monoalkyl substituted phosphinate, a copolymer of maleic acid and a monoalkyl substituted phosphonate, a copolymer of maleic acid and a comonomer, and mixtures thereof, wherein the comonomer is selected from the group consisting of vinyl acetate, methyl vinyl ether, and itaconic acid,
- separating the mat into substantially unbroken fibers individualized fibers;
- and
- curing the crosslinking agent to form individualized, polymaleic acid crosslinked cellulosic fibers.
Dependencies are inferred from the claim text.