Low-cellulose non-wood fiber product and method for making the same

Abstract

A method of preparing a non-wood fiber paper reinforcement product is disclosed. The method includes placing an additive in an aqueous alkaline medium, wherein the additive includes a hydroxycarboxylic acid; and mixing a non-wood fiber material with the placed additive in the aqueous alkaline medium to form a mixture, wherein the non-wood fiber material includes starch, protein, and fiber, wherein the additive, the starch, protein, and fiber of the non-wood fiber material, and the metal ions of the alkaline medium become physically cross-linked, which produces the non-wood fiber paper reinforcement product. In aspects, the non-wood fiber paper reinforcement product is used to make a paper product, wherein the paper product has greater strength than the same paper product made with native starch or chemically modified starch instead of the non-wood fiber paper reinforcement product.

Description

Field of the Invention

[0001] The present disclosure relates to low-cellulose products derived from non-wood fiber materials such as botanical flour. More specifically, but not exclusively, the present disclosure also relates to methods for making low-cellulose non-wood fiber products for the paper industry. The present disclosure also relates to methods for improving the strength of cellulose paper products while increasing repulpability. Background of the Invention

[0003] In the manufacture of paper products such as paperboard, the strength properties of the final product can be improved by adding so-called "strengthening agents". Strengthening agents can also allow the overall basis weight of the paper product to be reduced to obtain the same paper strength and save the cost of cellulosic raw materials. Conventional paper strengthening agents include chemically modified starches such as carboxyalkylated starch and cationic starch, urea / formaldehyde resins, melamine / formaldehyde resins, acrylamide copolymers, polyamidoamine / epichlorohydrin resins and chitosan.

[0004] Due to the increased interest in developing paper products based on recycled cellulose, great emphasis has been placed on developing paper that is easily repulpable. Many conventional repulping processes for paper products require the use of toxic reagents, are slow to perform, and often result in large amounts of waste that are landfilled and pollute the environment while wasting a valuable fiber source.

[0005] US20140166222A1 discloses a strengthening agent in the wet end of papermaking, which includes a surface-modified non-wood plant fiber and a chemically modified starch (cationic starch) component.

[0006] US2006225855A describes cationic starch derived from leguminous plants. The disclosed composition can be used as a strengthening agent in the paper industry.

[0007] EP 1631718 B1 discloses compositions for chemically modifying starch which are useful in the paper industry and which are derived from plants of the leguminous family.

[0008] Although some of these compositions do in fact improve the reinforcing properties relative to native starch using non-wood fiber materials, these methods are not economically practical due to increased energy costs, very dilute processing conditions, and high cellulosic materials. In addition, these non-wood fiber compositions contain chemically modified starches, which are also known as chemically cross-linked starches, in which intramolecular bonding occurs with the formation of covalent bonds. Therefore, the compositions and processes for producing these compositions cannot be called clean label, and the products are not biodegradable.

[0009] Still further, conventional methods are silent with respect to low-cellulose raw materials for making paper products. Therefore, there is a need to find low-cellulose non-wood fiber raw materials that are easy to process, especially with respect to the solvents used and the added reinforcing agents or reinforcing matrices, non-toxic and clean labeling conditions, and repulpable materials.

[0010] The object of the present invention is to overcome the disadvantages of the prior art described above and to provide a low cellulose non-wood fiber paper reinforcement product having mechanical properties to a similar or greater degree than products made using conventional methods. There is a need for improved products for use in the paper industry. For example, there is a need for a paper product made from a low cellulose non-wood fiber raw material that still has at least the same or similar paper strength as a paperboard product made with conventional amounts of high cellulose raw materials.

[0011] Overview

[0012] The present invention provides advantages over conventional methods and products. The present invention includes compositions of low-cellulose fiber raw materials used as non-wood fiber paper strengtheners and methods for improving the strength of cellulose paper products while increasing repulpability. In aspects, the low-cellulose non-wood fiber raw material is a plant flour. More specifically, the plant flour is legume flour or bean flour. In preferred aspects, the plant flour is pea legume flour. In aspects, the pea legume flour is a pea legume flour stream from any treatment that promotes size reduction of the particles. For example, such treatment can involve various types of grinding or milling (e.g., dry grinding, wet grinding, wet classification or vibratory ball milling). In aspects, the preferred treatment is a wet classification process, wherein the pea legume flour contains starch, protein and fiber.

[0013] In one aspect, the present invention is a method of making a starch-containing product made from a low-cellulose non-woody fiber raw material, wherein the starch-containing product has greater paper strength than a conventional paperboard product made with a conventional amount of a high-cellulose woody raw material. As used herein, the term "paper strength" includes at least one strength property commonly used in the papermaking industry, such as tensile strength (TAPPI method T-404) or bursting strength (Mullen Index test, also known as TAPPI method T-403). In one aspect of the present invention, a method includes mixing a non-woody fiber material, particularly plant flour, and old, corrugated container pulp slurry to form a mixture; heating the mixture; using the mixture to prepare a uniform sheet; and drying the sheet to produce a paper product; wherein the paper product has a paper strength greater than a paper product made in the same manner but with native starch or chemically modified starch.

[0014] In aspects of the present invention, a method comprises placing an additive in an aqueous alkaline medium, and adding a non-wood fiber material comprising starch, protein and fiber to the medium, wherein the additive, the non-wood fiber material and the metal ions of the alkaline medium become physically cross-linked, which produces a low-cellulose non-wood fiber paper reinforcement product. In an embodiment, the non-wood fiber material is a plant powder. As used herein, the term "physically cross-linked" means connected by at least one interaction selected from intermolecular forces, hydrogen bonds, ionic bonds, complexation and electrostatic interactions. In aspects, physical connection is achieved due to the abundant hydroxyl groups in starch and additives, the carboxylate groups of the additives, the functional groups of the protein and the alkali metal of the medium. In aspects, the non-wood fiber paper reinforcement product can be used to make paperboard, wherein the paperboard has at least the same paper strength as paperboard made with a rich chemical modification product, and is derived from a low-cellulose non-wood fiber raw material.

[0015] In aspects, the process is carried out solely in an alkaline aqueous medium and in the absence of a co-solvent, wherein the amount of plant powder is greater than 20% by weight of the mixture.

[0016] In aspects, the additive is a hydroxycarboxylic acid. As used herein, hydroxycarboxylic acid is intended to mean any acid having at least one hydroxyl functional group and at least one carboxylic acid functional group.

[0017] In aspects, the mixing of the additive and the plant powder in an alkaline aqueous medium is performed in a semi-dry process step, for example, less than 30% moisture by weight of the mixture. In aspects, the method is performed at a pH equal to or greater than 8.

[0018] In one aspect, after mixing the additive in the alkaline aqueous medium with the plant powder, the mixture is heated, such as in an oven. In one aspect, after heating, the product is washed with water and dried.

[0019] In yet further aspects, the present disclosure relates to the use of non-wood fiber paper reinforcement products in paper products, absorbent paper products, packaging materials, and filters.

[0020] These and other aspects, embodiments and associated advantages will become apparent from the following detailed description.

[0021] Detailed Description

[0022] In order to provide a clear understanding of the terms used in this specification, some definitions are provided below.

[0023] As used in this specification and claims, the term "comprising" and its derivatives, as used herein, are similarly intended to be open-ended terms that specify the presence of stated features, elements, components, groups, integers, and / or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers, and / or steps. This understanding also applies to words with similar meanings, such as "including," "having," and their derivatives. As used herein, the term "consisting" and its derivatives are intended to be closed terms that specify the presence of stated features, elements, components, groups, integers, and / or steps, but exclude the presence of other unstated features, elements, components, groups, integers, and / or steps.

[0024] As used in this specification and claims, the term "about" is defined as approaching, and in one non-limiting aspect, the term is defined as within 5%, preferably within 1%, and more preferably within 0.5%.

[0025] As used herein, the terms "physical cross-linked", "cross-linked", "linked" refer to being linked by at least one interaction selected from intermolecular forces, hydrogen bonds, ionic bonds, complexation and electrostatic interactions. Non-limiting examples of these physical cross-linking interactions include interactions of hydroxyl groups contained in starch and additives, carboxylate groups of additives, functional groups contained in proteins, and alkali metals of the medium, or any combination thereof.

[0026] Examples of suitable starches include corn starch, sweet potato starch, potato starch, tapioca starch, wheat starch, related vegetable starch and hydrolyzed starch. In a preferred embodiment, the starch is corn starch.

[0027] As used herein, the terms "paper" and "paperboard" are used interchangeably. As used herein, the term "non-wood fiber" generally refers to any material that is not derived from wood, wherein wood is understood to mean the hard fibrous material present under the bark in the trunk and branches of a tree. Suitable non-wood fiber materials can come from agricultural residues (agricultural residue), grass, botanicals (botanical) or other plant materials (plant material) such as straw, leaves, bark, seeds, shells, flowers, vegetables or fruits, or from cotton, corn, wheat, oats, rye, barley, rice, soybeans, flax, bagasse, bamboo or reeds. Agricultural residues come from roots or tubers, corn, peas, wheat or a combination thereof. Non-wood fiber can also come from algae or fungi or be bacterially derived.

[0028] As used herein, "non-wood fiber paper reinforcement products" are well suited for use as reinforcement agents in the paper industry, as packaging materials, and as paper products. Non-limiting examples of such packaging materials are labels, corrugated boxes, liquid packaging boards (milk cartons, juice cartons, beverage cartons), folding and non-folding cartons and boxes. This can include packaging materials for protecting the display portion of electronic devices such as laptop computers, smart phones or smart watches. The non-wood fiber paper reinforcement products of the present invention are also suitable for use in absorbent paper products (e.g., napkins, tissues and liners), adhesives and filters (e.g., cigarette filters and water filters).

[0029] As used herein, the expressions "legumes" or "legume origin" for the purposes of the present invention are understood to mean representatives of beans, peas, lentils, alfalfa, cloves and lupins, and in particular, pea legumes are preferred in the present invention.

[0030] Therefore, unless otherwise indicated, any definitions or embodiments described in this section or other sections are intended to be applicable to all embodiments and aspects of the subject matter described herein to which they would be applicable as understood by one of ordinary skill in the art.

[0031] In aspects, there is a composition of low-cellulose non-wood fiber raw materials used as non-wood fiber paper strengtheners. For example, the low-cellulose non-wood fiber material is a plant meal, such as pea legume meal. The pea legume meal can be a stream containing pea legumes from various types of processing, including but not limited to wet milling, dry milling, vibratory ball milling, or any process known in the art. In aspects, a wet classification process is preferred, wherein the raw low-cellulose pea legume meal side stream contains a biobased substitute. In yet another aspect of the present disclosure, the pea legume meal side stream contains starch, protein, and fiber. In particular, the non-wood fiber material or a combination thereof can contain from about 70% to about 85% starch by weight, equal to or greater than 5% to 10% protein by weight and from about 5% to about 25% fiber by weight and about 2% or less low-fat matter by weight, and can also contain less than 10% moisture (i.e., water) by weight. The starch content of the flour is preferably less than 85% by weight, more preferably less than 80% by weight, and most preferably less than 75% by weight.

[0032] In aspects, the non-wood fiber paper reinforcement product or reinforcement has all the characteristics already listed above. These also apply to any combination of non-wood fiber materials.

[0033] In aspects, the composition further comprises a hydroxycarboxylic acid. In aspects of the invention, a method comprises placing an additive in an aqueous alkaline medium and adding to the medium a non-woody cellulosic material comprising starch, protein and fiber, wherein the additive, the non-woody cellulosic material and metal ions of the alkaline medium become physically cross-linked, which produces a low cellulose non-woody cellulosic paper reinforcement product.

[0034] In one aspect, the present invention is a method of making a non-wood fiber paper reinforcement product from a non-wood fiber material such as legume or bean flour, the method comprising (1) obtaining a legume or bean flour side stream from a wet fractionation process, the legume or bean flour side stream comprising starch, protein and fiber, (2) placing an additive in an aqueous alkaline medium, and (3) adding the legume or bean flour side stream to the medium, wherein the additive, the legume or bean flour side stream and the metal ions are physically cross-linked. In one aspect, the non-wood fiber paper reinforcement product is used to make paperboard, wherein the paperboard has at least the same paper strength as paperboard made with a chemically modified product and is derived from a low cellulose raw material.

[0035] The method disclosed herein using the low-cellulose non-wood raw material derived from plant powder such as legume powder or bean powder is advantageous from an economic point of view relative to conventional methods and products. The cost of low-cellulose raw materials is much lower than that of chemically modified starch and native starch. Due to the elimination of purified native starch from protein and fiber substitutes, energy costs are significantly reduced. Advantageously, method of the present invention and low-cellulose non-wood fiber materials include plant powder, such as low-cellulose raw material legume powder or bean powder, which is opposite to concentrates and isolates of starch and protein. Surprisingly, it has been found that using low-cellulose pea legume powder in papermaking has good mechanical properties that starch concentrates and chemically modified starch do not show. The reinforcing properties of the low-cellulose non-wood fiber products formed with such powder are suitable for use in papermaking industry and packaging industry, to manufacture a variety of products.

[0036] In aspects, the non-wood fiber paper reinforcement product or reinforcement has all the characteristics already listed above. These also apply to any combination of non-wood fiber materials.

[0037] In one aspect, the base of the alkaline aqueous medium is selected from one of sodium hydroxide, lithium hydroxide, potassium hydroxide and mixtures thereof. The preferred base is sodium hydroxide.

[0038] In the aspect, the additive is a hydroxycarboxylic acid. Preferably, the hydroxycarboxylic acid is a derivative of glucaric acid or glucaric acid. In addition, any salt of such an acid that forms a carboxylate ion can also be used as a reinforcing agent in the present invention. It has been found that carboxylates exhibit strong intermolecular bonds, which are beneficial to obtaining improved mechanical properties and reinforcing properties of paperboard and packaging containers. Without being bound by theory, the ionic properties of carboxylates allow strong intermolecular bonds to be formed between carboxylates, starch, proteins and fibers of non-wood fiber materials and metal ions of alkaline media, making them physically cross-linked, which produces non-wood fiber paper reinforced products. Non-wood fiber paper reinforced products provide enhanced mechanical properties and reinforcing properties, which are suitable for incorporation into paper industry products and the like. Surprisingly, non-wood fiber paper reinforced products, as products comprising starch manufactured from low-cellulose non-wood fiber materials, provide at least the same or similar paper strength as conventional paperboard products manufactured with conventional amounts of high-cellulose wood raw materials.

[0039] Glucaric acid may have the structure of Formula (I) as follows:

[0040]

[0041] In other aspects, the glucaric acid may be in the form of a carboxylate salt and have the structure of formula (II)

[0042]

[0043] wherein Z+ is selected from one of hydrogen, sodium, potassium or lithium and combinations thereof. In an embodiment, the glucaric acid may be in the form of a carboxylate and have a structure of formula (II) comprising an alkali metal such as sodium, potassium or lithium and combinations thereof.

[0044] Glucaric acid can be provided by microbial fermentation, oxidation of sugars (e.g. glucose) or polysaccharides (e.g. starch).Therefore, glucaric acid is easily available and can be provided in an economically green manner.

[0045] In aspects, the salt of the hydroxycarboxylic acid is generated in situ, meaning that a composition according to the invention, a hydroxycarboxylic acid such as glucaric acid and a suitable base such as sodium hydroxide are combined. It should be noted that these conditions are unique and care is taken to avoid alkaline catalysis that could significantly damage and hydrolyze the starch component or that could degrade the protein to amino acids in the pea legume meal side stream.

[0046] To obtain a suitable carboxylate content, the pH of the mixture is preferably at least 8.0.

[0047] The composition may comprise from greater than 0% to about 25% by weight of the composition, such as from about 3% to about 20% by weight of the composition, of glucaric acid. The composition may comprise plant meal, such as a pea legume meal side stream, and glucaric acid in a weight ratio of from about 10:1 to about 0.5:1 (plant meal / glucaric acid), such as from about 5:1 to about 1:1.

[0048] In aspects, the mixing of the additive and the plant powder is in a process step where the moisture content of the mixture is less than 50% by weight.

[0049] In aspects, a process is disclosed that provides high yield and minimizes by-products by physically cross-linking a substitute for plant flour, such as pea legume flour, with a polyhydroxy carboxylic acid, such as glucaric acid or its salts, metal ions, and combinations thereof, to produce a favorable product matrix comprising starch, fiber, and protein.

[0050] In aspects, the method comprises heating a mixture of an additive, a plant meal (such as a pea legume meal), and an aqueous alkaline medium to a temperature of at least 80°C, preferably within 80°C-105°C, more preferably within 90°C-105°C, and holding there for a sufficient time to obtain a product matrix, but not so long as to allow excessive destruction or hydrolysis of the bio-based substitute. In embodiments, the heating time may be about 90 minutes to 180 minutes. Typically, the total heating time should not exceed about 3 hours. Those skilled in the art having the benefit of the present invention will be able to readily adjust the reaction time and temperature to optimize the enhanced properties of the product matrix without undue experimentation.

[0051] In one aspect, by introducing the non-woody cellulose material comprising low-cellulose plant powder (e.g., leguminous plant powder or bean powder) according to the present disclosure into a papermaking method, such paper can be obtained, which has substantially the same or improved properties as the paper in which chemically modified starch (e.g., chemically cross-linked cationic starch) is used. In addition, the low-cellulose non-woody cellulose material treated according to the present invention can be used as an adhesive for fixing corrugations in corrugated board.

[0052] In aspect, a method for improving the mechanical properties of cellulose paper has been generally achieved, the method comprising adding a component of the present invention to the paper during the papermaking process, the component comprising a low-cellulose non-wood fiber product derived from a low-cellulose non-wood fiber material. The process for making a paper product or a repulpable paper product according to the present invention comprises forming an aqueous slurry of papermaking fibers or pulp, or can be carried out by a known conventional pulping process. Another step comprises adding the product of the present invention to the aqueous slurry of papermaking fibers or pulp, the product comprising non-wood fiber materials or non-wood fiber products. Without being bound by theory, the non-wood fiber materials or non-wood fiber products form strong physical crosslinks with the pulp fibers. In addition, due to the multifunctional structure of the pulp fibers and non-wood fiber products of the present invention, the strong physical connection improves the mechanical properties of paper used in the papermaking industry.

[0053] In one aspect, the present disclosure relates to a non-wood fiber paper product derived from a low-cellulose raw material characterized by a tensile strength of at least 40 Nm / g and a burst strength of at least 2.0 KN / g. These physical properties of tensile strength based on TAPPI method T-404 and burst strength based on the Mullen Index test (also known as TAPPI method T-403) meet typical specifications in the papermaking industry.

[0054] In an aspect, a repulpable and biodegradable non-wood fiber paper strength agent is disclosed.

[0055] The present invention is more specifically described by the following examples. Example

[0056] The methods and product matrices disclosed herein are illustrated in the following examples. From the above discussion and these examples, one skilled in the art can ascertain the essential characteristics of the invention and, without departing from its spirit and scope, can make various changes and modifications to the invention to adapt it to various uses and conditions.

[0057] The present invention is more specifically described by the following examples.

[0058] All commercial reagents were used as received. Native corn starch ADM Clinton 106, cationic starch ADM with a degree of substitution of 0.1 Clin-Cat 830, and cationic starch ADM with a degree of substitution of 0.04 Clin-Cat810, glucaric acid (Sigma Aldrich), sodium hydroxide (Sigma Aldrich), and low cellulose raw material pea legume meal side stream (Archer Daniels Midland Company, ADM). Old corrugated container ("OCC") pulp slurry was prepared from cardboard boxes (Amazon) after pulping with water. Non-wood fiber paper reinforcement products were produced according to a preferred embodiment of the present invention.

[0059] The following abbreviations are used or may be used in the examples: “RPM” means revolutions per minute; “DS” means degree of substitution; “°C” means degrees Celsius; “KN” means kilonewton; “Nm / g” means Newton per meter per gram; “L” means liter; “mL” means milliliter; “min” means minute; “OCC” means old corrugated container; and “g” means gram.

[0060] Examples 1 and 2 relate to the preparation of two products of a low-cellulose pea legume side stream, glucaric acid, and an alkaline medium containing an alkali metal for use as a repulpable and biodegradable non-wood fiber paper reinforcement product. The reinforcement product was prepared by placing 1 g or 5 g of the desired amount of glucaric acid in 20 mL of an alkaline aqueous medium (0.1 N sodium hydroxide) in a 50 mL cup. The low-cellulose pea legume flour side stream was added to the cup, and the slurry was vigorously mixed using a spatula. The resulting slurry was then placed in a conventional oven and heated to 105° C. for 90 minutes. The mixture was removed and allowed to dry at room temperature. These non-wood fiber paper reinforcement products containing the glucaric acid additive were subsequently tested in the manufacture of paper sheets.

[0061] The protocol for preparing laboratory hand sheets was based on the procedure derived from TAPPI standard method T 205. The selected matrix or reinforcing agent (0.5 g) was added to an OCC pulp slurry (0.3% in water, 10 L) in a plastic bucket. The slurry was stirred at 500 rpm for 15 min. The temperature of the mixed slurry was maintained at 35°C and the pH was 6. 500 mL of the prepared slurry was used to prepare a uniform sheet. The sheet was dried in a condition room and cured at 110°C for 45 min. For each paper sheet produced, traditional physical properties such as tensile strength and burst strength were determined and found to be satisfactory for use in paper products.

[0062] Following the general procedure for making paper sheets mentioned above, the substrates of Examples 1-2, a control of low cellulose pea legume flour (Example 3), and conventional strengthening agents such as native corn starch (Example 4) or cationic starch (Example 5-Example 6) were incorporated into paper for comparative testing. Table 1 summarizes the mechanical properties of non-wood fiber paper strengthening agents made according to the present invention and conventional strengthening agents.

[0063] Table 1

[0064]

[0065] Examples 1 and 2 show the benefits of low-cellulose non-wood fiber materials containing raw pea legume flour, particularly a composition of 70% starch, 8% protein, 16% fiber, 1% fat and 5% moisture together with glucaric acid, in terms of mechanical and reinforcing properties. As summarized in Table 1, such new non-wood paper reinforcement products of Examples 1 and 2 clearly show superior mechanical properties compared to conventional reinforcement agents (e.g., native starch and chemically modified starch) of Examples 4-6.

[0066] Example 3 relates to the addition of a sole low cellulose pea legume flour to the papermaking process, and in a particularly surprising and unexpected manner, the addition of a sole low cellulose pea legume flour to the papermaking process has improved tensile strength when compared to the conventional strengthening agents of Examples 4-6. The addition of a sole low cellulose pea legume flour has a significant advantage in terms of bursting index when compared to native starch and low substituted cationic starch, as presented in Examples 3, 4 and 5, and is similar to the bursting index of highly substituted cationic starch as presented in Example 6.

[0067] The present disclosure has been described with reference to certain exemplary embodiments, compositions and uses thereof. However, one of ordinary skill in the art will recognize that various substitutions, changes or combinations may be made to any of the exemplary embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited by the description of the exemplary embodiments, but is limited by the originally filed attached claims.

Claims

1. A composition for use as a non-wood fiber paper strengthening agent, comprising: a non-woody cellulosic material comprising from 70% to 85% by weight starch, equal to or greater than 5% and up to 10% by weight protein, and from 5% to 25% by weight fiber; and An alkaline medium containing an alkali metal.

2. The composition according to claim 1, further comprising from 0% up to 2% by weight fat.

3. A composition according to claim 1 or claim 2, further comprising less than 10% by weight of moisture.

4. The composition according to claim 1 or 2, further comprising a hydroxycarboxylic acid.

5. The composition according to claim 3, further comprising a hydroxycarboxylic acid.

6. The composition according to claim 4, wherein the hydroxycarboxylic acid is at least one selected from the group consisting of glucaric acid and derivatives of glucaric acid.

7. The composition according to claim 5, wherein the hydroxycarboxylic acid is at least one selected from the group consisting of glucaric acid and derivatives of glucaric acid.

8. The composition of claim 1, wherein the alkali metal is sodium, lithium, potassium, or any combination thereof.

9. The composition of any one of claims 1, 2, and 5-8, wherein the non-wood cellulosic material is of leguminous origin.

10. The composition of claim 3, wherein the non-wood cellulosic material is of leguminous origin.

11. The composition of claim 4, wherein the non-wood cellulosic material is of leguminous origin.

12. The composition of claim 9, wherein the leguminous plant is bean or pea, or a combination thereof.

13. The composition of claim 10 or 11, wherein the leguminous plant is bean or pea, or a combination thereof.

14. A method for making a paper product, comprising: mixing the composition of any one of claims 1 to 13 with a pulp slurry to form a mixture; as well as The mixture is formed into a sheet.

15. The method of claim 14, further comprising heating the mixture.

16. A method according to claim 14 or claim 15, further comprising drying the sheet.

17. A product produced by the method of any one of claims 14 to 16, wherein the product has a tensile strength and a burst strength greater than a paper product made in the same manner but using native starch or chemically modified starch.

18. A method for producing the composition of any one of claims 1-13, the method comprising: placing the non-wood cellulosic material in an aqueous medium, thereby producing a mixture; as well as heating the mixture at a temperature of at least 80° C., The aqueous medium is a basic medium containing an alkali metal.

19. The method of claim 18, further comprising mixing a hydroxycarboxylic acid in the aqueous medium.

20. The method of any one of claims 18-19, wherein heating the mixture is at a temperature of 80°C to 105°C.

21. The method according to claim 20, wherein the heating at a temperature of 80°C to 105°C lasts for 90 minutes to 180 minutes.

22. The method according to any one of claims 18-19 and 21, wherein the mixing is carried out at less than 30% moisture by weight of the mixture.

23. The method of claim 20, wherein the mixing is performed at less than 30% moisture by weight of the mixture.

24. A method comprising: placing an additive in an alkaline medium comprising an alkali metal, wherein the additive comprises a hydroxycarboxylic acid; mixing a non-wood cellulosic material with the additive in the alkaline medium to form a mixture, wherein the non-wood cellulosic material comprises starch, protein, and fiber; The additive, the components of the non-wood fiber material and the metal ions of the alkaline medium become a non-wood fiber paper reinforcement product.

25. The method of claim 24, further comprising heating the mixture at a temperature of at least 80°C.

26. The method of claim 25, wherein the mixture is heated at a temperature of 80°C to 105°C.

27. The method of claim 24, further comprising heating the mixture at a temperature of 90°C to 105°C.

28. The method of claim 25, wherein the heating at a temperature of at least 80°C lasts for 90 minutes to 180 minutes.

29. The method of claim 26, wherein the heating at a temperature of 80°C to 105°C lasts for 90 minutes to 180 minutes.

30. The method of claim 27, wherein the heating at a temperature of 90°C to 105°C lasts for 90 minutes to 180 minutes.

31. The method of claim 24, wherein the mixing is performed at less than 30% moisture by weight of the mixture.

32. The method of claim 24, wherein the non-wood fiber material is 70%-85% by weight starch, 5%-10% by weight protein, 5%-25% by weight fiber, 1%-2% or less low fat matter by weight, and 5%-10% or less moisture by weight.

33. The method of claim 24, wherein the non-wood cellulosic material is less than 75% by weight starch.

34. The method of claim 24, wherein the hydroxycarboxylic acid is selected from at least one of glucaric acid and a derivative of glucaric acid.

35. The method of claim 24, wherein the non-wood cellulosic material is selected from agricultural residues, grasses, or combinations thereof.

36. The method of claim 24, wherein the non-wood cellulosic material is pea legume meal.

37. The method of claim 24, wherein the non-wood cellulosic material is obtained from a wet fractionation process stream.

38. The method of claim 24, further comprising incorporating the non-wood fiber paper reinforcement product into paper to form a reinforced paper, wherein the reinforced paper has greater strength than paper having a native starch or a chemically modified starch as a reinforcement agent.

39. The method of claim 24, further comprising: preparing a uniform sheet using the mixture; as well as drying the sheet to produce a paper product; The paper product has a tensile strength and a burst strength greater than a paper product made in the same manner but using native corn starch or chemically cross-linked cationic corn starch.

40. The method of claim 39, wherein the non-wood cellulosic material is pea legume meal.

41. A non-wood fiber paper reinforcement product made according to the method of claim 24.

42. A physically cross-linked product comprising plant powder, metal ions from an alkaline medium comprising an alkali metal, and a cross-linking additive, wherein the cross-linking additive is a hydroxycarboxylic acid, wherein the physical cross-linking is achieved via association through at least one interaction selected from intermolecular forces, hydrogen bonding, ionic bonding, complexation, and electrostatic interactions.

43. The physically crosslinked product of claim 42, wherein the hydroxycarboxylic acid is selected from at least one of glucaric acid and derivatives of glucaric acid.

44. The physically cross-linked product of claim 42, wherein the vegetable flour is selected from leguminous plant flour or bean flour, or a combination thereof.

45. The physically cross-linked product of claim 42, wherein the plant meal is pea legume meal.

46. ​​A paper product comprising the physically crosslinked product of claim 42.

47. A method for making a paper product, comprising: mixing legume flour or bean flour, an alkaline medium containing an alkali metal, and a slurry of old corrugated container pulp to form a mixture; heating the mixture; Using the mixture to prepare a uniform sheet; and drying the sheet to produce a paper product; The paper product has a tensile strength and a burst strength greater than a paper product made in the same manner but using native corn starch or chemically cross-linked cationic corn starch.

48. The method of claim 47, wherein the legume meal is pea legume meal.

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