Lignin/polyacrylonitrile-containing dopes, fibers, and methods of making same
AssigneeWeyerhaeuser NR Company
InventorsPaul J. Bissett, Carole W. Herriott
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Abstract
The invention relates to a process for preparing a composition comprising 10 to 45% of the total solids weight lignin, polyacrylonitrile or a polyacrylonitrile copolymer, and a solvent to form a lignin-based polyacrylonitrile-containing dope and the resulting products. The dope can be processed to produce fibers, including precursor, oxidized and carbonized fibers. The oxidized fibers are of value for their flame resistant properties and carbonized fibers are suitable for use in applications requiring high strength fibers, or to be used to form composite materials.
Claims14
A fiber dope solution comprising lignin, and polyacrylonitrile or polyacrylonitrile copolymer, in an organic solvent that dissolves both the lignin and the polyacrylonitrile or polyacrylonitrile copolymer, wherein the solution has a solids content of from 10 to 35% of the total weight of the solution, wherein the lignin is 5 to 45% of the total weight of solids in the solution and wherein solution has a viscosity of 20 to 1500 poise at a temperature of 20° C. to 80° C.
A method of producing a fiber dope solution comprising combining lignin, and polyacrylonitrile or polyacrylonitrile copolymer, and an organic solvent that dissolves both the lignin and the polyacrylonitrile or polyacrylonitrile copolymer, to produce a fiber dope solution having a viscosity of about 20 to about 1500 poise at a temperature of about 20° C. to about 80° C., wherein the total solids in the solution is 10 to 35% of the total weight of the solution, and wherein the weight of the lignin in the solution is 5 to 45% of the weight of the solids in the solution.
Dependencies are inferred from the claim text.