Carboxylated cellulosic fibers
AssigneeWeyerhaeuser Company
InventorRichard A. Jewell
Life of this patent
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Abstract
Carboxylated cellulosic fibers having a polycarboxylic acid covalently coupled thereto and a water retention value greater than or equal to the water retention value of the fibers from which the carboxylated fibers are formed; fibrous products that incorporate the carboxylated fibers; methods for making the fibers; and methods for making the fibrous products that incorporate the fibers.
Claims29
Carboxylated cellulosic fibers, comprising:
- (a) individual carboxylated cellulosic fibers wherein the fibers are covalently coupled to a carboxylating agent through an ester bond,
- (b) wherein the carboxylating agent provides a free carboxyl group to the fibers,
- (c) wherein the carboxylating agent is a polycarboxylic acid having one carboxyl group separated from a second carboxyl group by either two or three atoms, and
- (d) wherein the carboxylated fibers are substantially non-crosslinked as measured by the water retention value of the carboxylated fibers being greater than or equal to the water retention value of the untreated fibers from which the carboxylated fibers are formed.
A method for preparing individualized, carboxylated cellulosic fibers, comprising:
- (a) applying a carboxylating agent to a fibrous mass, wherein the carboxylating agent is a polycarboxylic acid having one carboxyl group separated from a second carboxyl group by either two or three atoms;
- (b) separating the fibrous mass into individual, substantially unbroken fibers;
- and
- (c) heating the individualized fibers to form an ester bond between the carboxylating agent and the fibers, wherein the carboxylated fibers are substantially non-crosslinked as measured by the water retention value of the carboxylated fibers being greater than or equal to the water retention value of the untreated fibers from which the carboxylated fibers are formed.
Carboxylated cellulosic fibers, comprising:
- (a) individual carboxylated cellulosic fibers wherein the fibers are covalently coupled to a dicarboxylic acid through an ester bond,
- (b) wherein the dicarboxylic acid provides a free carboxyl group to the fibers,
- (c) wherein the dicarboxylic acid has one carboxyl group separated from a second carboxyl group by either two or three atoms, and
- (d) wherein the carboxylated fibers are substantially non-crosslinked as measured by the water retention value of the carboxylated fibers being greater than or equal to the water retention value of the untreated fibers from which the carboxylated fibers are formed.
A method for preparing individualized, carboxylated cellulosic fibers, comprising:
- (a) applying a dicarboxylic acid to a fibrous mass, wherein the dicarboxylic acid has one carboxyl group separated from a second carboxyl group by either two or three atoms;
- (b) separating the fibrous mass into individual, substantially unbroken fibers;
- and
- (c) heating the individualized fibers to form an ester bond between the dicarboxylic acid and the fibers, wherein the carboxylated fibers are substantially non-crosslinked as measured by the water retention value of the carboxylated fibers being greater than or equal to the water retention value of the untreated fibers from which the carboxylated fibers are formed.
Dependencies are inferred from the claim text.