Additive for fiber strengthening
Compositions that include a polymer and an aldaric acid, such as glucaric acid, are disclosed. The compositions may include polyvinyl alcohol and glucaric acid. The compositions may also include polyacrylonitrile and glucaric acid. In addition, the compositions may further include lignin. Also disclosed are fibers including the compositions, methods of making the fibers, and uses of the fibers.
1. A composition comprising:
a polymer having a plurality of hydroxyl groups or nitrile groups;
an aldaric acid or a salt thereof: and
an additive selected from the group consisting of lignin, carbon nanotubes, nanofillers and a combination thereof.
2. The composition of claim 1 , wherein the aldaric acid is glucaric acid.
3. The composition of claim 1 , wherein the polymer comprises a straight or branched polyalkylene substituted with the plurality of hydroxyl groups or nitrile groups.
4. The composition of claim 1 , wherein the polymer comprises recurring units of the formula (I)
wherein:
L is C 0-3 alkylene;
X is —OH or nitrile;
n is 1 to 1000; and
m is 100 to 100,000.
5. The composition of claim 1 , wherein the polymer comprises polyvinyl alcohol, polyvinyl alcohol derivatives, polyvinyl alcohol copolymers, or a combination thereof.
6. The composition of claim 1 , wherein the polymer comprises polyacrylonitrile, polyacrylonitrile derivatives, polyacrylonitrile copolymers, or a combination thereof.
7. The composition of claim 6 , wherein the polyacrylonitrile copolymer is a copolymer of polyacrylonitrile and another polymer selected from the group consisting of acrylic acid, itaconic acid, and acrylates.
8. The composition of claim 1 , wherein the polymer has a molecular weight of from about 100 kDa to about 400 kDa.
9. The composition of claim 1 , comprising the polymer at from about 30% to about 99.9% by weight of the composition.
10. The composition of claim 2 , comprising the glucaric acid or a salt thereof at from about 0.01% to about 10% by weight of the composition.
11. The composition of claim 2 , comprising the polymer and the glucaric acid at a weight ratio of from about 5/1 to about 10,000/1 (polymer/glucaric acid).
12. The composition of claim 2 , wherein the glucaric acid is an ammonium salt of glucaric acid.
13. A fiber comprising the composition of claim 1 .
14. The fiber of claim 13 , having at least one of:
(i) an average diameter of from about 10 μm to about 50 μm;
(ii) a tenacity of greater than 5 g/den;
(iii) a specific modulus of greater than 250 g/den;
(iv) a tensile strength of greater than 500 MPa; and
(v) a linear density of less than 15 denier.
15. A concrete additive comprising the fiber of claim 13 .
16. A fibrous article comprising the fiber of claim 13 , wherein the article is selected from the group consisting of yarn, fabric, melt-blown web, spunbonded web, gel-spun web, thermobonded web, hydroentangled web, nonwoven fabric, and a combination thereof.
17. A method of making a fiber, the method comprising:
dissolving a polymer having a plurality of hydroxyl and/or nitrile groups and an aldaric acid or a salt thereof in a first solvent to provide a solution;
heating the solution;
extruding the solution into a first bath comprising a second solvent to provide a gel- spun fiber;
aging the gel-spun fiber to provide an aged gel-spun fiber; and
drawing the aged gel-spun fiber through a second bath comprising silicone oil to provide the fiber.
18. The method of claim 17 , wherein the aldaric acid is present in the solution at from about 0.01% to about 5% by weight/volume.
19. The method of claim 17 , wherein the aldaric acid is glucaric acid.