Slurry composition for high-quality paper product and application of slurry composition

Abstract

The invention belongs to the field of paper products, and particularly relates to a pulp composition for a high-quality paper product and application of the pulp composition. The bio-based additive comprises a component A, a component B and a component C, wherein the component A is one or two of a biomass material with a dendritic or network-shaped structure or a cationized biomass material with a dendritic or network-shaped structure; and optionally containing or not containing a component B: one, two or more selected from the group consisting of polyhydroxyalkanoates, alkyl ketene dimers, polyglycolide, polylactide, copolymers of butylene adipate and butylene terephthalate, polyoxyethylene stearate, cellulose esters and cellulose ethers. A large number of hydroxyl groups are distributed in the component A, the hydroxyl groups can form hydrogen bonds with cellulose and the like in fiber pure pulp to form a larger network structure, the prepared paper product is high in strength, meanwhile, the hydrogen bonds and the hydroxyl groups are beneficial to water interception, and the water absorption of the paper product can be improved.

Description

Technical Field

[0001] The invention belongs to the field of paper products, and in particular relates to a pulp composition for high-quality paper products and application thereof. Background Art

[0002] High-quality paper products such as medical paper (such as medical crepe paper), analytical and testing paper (such as absorbent paper), filter paper (such as chromatography paper), tobacco paper (such as tobacco sheet paper), etc., are not only required to have good physical properties such as ring crushing, tearing, bursting resistance, tensile strength, etc., but also to add as little non-paper fiber components as possible.

[0003] Among them, analytical extraction filter elements, medical filtration equipment filter elements, food and drug filtration equipment and other filter paper products have extremely high requirements for the purity of raw materials. The addition of any non-paper additives may interfere with the results of scientific research analysis or pose a migration risk to the food and drug production process. Therefore, during the production process, non-cellulose chemicals cannot be used to improve strength indicators, resulting in the long-term defect of insufficient product strength in filter paper products.

[0004] Tobacco pulp is made from tobacco waste such as tobacco stems, tobacco leaf fragments and tobacco dust. However, since tobacco stems, tobacco leaf fragments, tobacco dust and other tobacco waste have short fibers and high non-fiber content, the fibers and non-fiber components will be severely cut and damaged during the pulping process, and the pulp after pulping contains high content of fine fibers and fine fragments. Therefore, the tobacco sheets made directly from tobacco pulp for papermaking have poor performance and are prone to paper breakage during production. In order to improve the strength, a certain proportion of external fibers, that is, high-quality wood pulp other than tobacco pulp, is generally added, but the addition of high-quality wood pulp will affect the taste.

[0005] Medical crepe paper and absorbent paper need to have good water absorption, and usually wet strength agents are added to improve the water absorption. However, wet strength agents are usually petroleum-based wet strength agents, and the addition of wet strength agents will introduce new organic matter and affect the biodegradability of paper products; at the same time, adding a large amount of wet strength agents will cause mold clogging and mucous membrane problems, reducing preparation efficiency. Summary of the invention

[0006] In order to improve the deficiencies of the prior art, the present invention provides a slurry composition and its application in high-quality paper products. By using biomass materials with dendritic or network structures and / or cationized biomass materials with dendritic or network structures to replace traditional petroleum-based wet strength agents, not only can the strength and hygroscopicity of paper products be improved, but also it is more environmentally friendly.

[0007] The present invention provides a pulp composition for high-quality paper products, the pulp composition comprising pure fiber pulp and a bio-based additive;

[0008] The bio-based additives include:

[0009] Component A: one or both of a biomass material having a dendritic or network structure or a cationized biomass material having a dendritic or network structure;

[0010] Optionally containing or not containing component B: one, two or more selected from PHA (polyhydroxyalkanoate), AKD (alkyl ketene dimer), PGA (polyglycolide), PLA (polylactide), PBAT (copolymer of butylene adipate and butylene terephthalate), polyoxyethylene stearate, cellulose ester, guar gum, light CaCO3, cellulose ether, for example, a combination of PHA and AKD;

[0011] According to an embodiment of the present invention, the composition comprises 90 to 100 parts of pure fiber pulp and 1 to 10 parts of bio-based additives by weight, preferably the composition comprises 95 to 100 parts of pure fiber pulp and 4 to 8 parts of bio-based additives, for example, the composition comprises 96 parts of pure fiber pulp and 4 parts of bio-based additives.

[0012] According to an embodiment of the present invention, the high-quality paper product refers to a paper product with a water absorption of ≥6 g / g and a tensile strength of ≥1.5 KN / m, and the paper product does not contain petroleum-based organic matter.

[0013] According to an embodiment of the present invention, the fiber pure pulp includes but is not limited to a mixture of one or more of wood pulp, straw pulp, bamboo pulp or bagasse pulp fiber pure pulp, for example, one, two or more of bamboo pulp, reed pulp, straw pulp, etc., exemplified by bamboo pulp.

[0014] According to an embodiment of the present invention, the component A and the component B do not contain a wet strength agent and / or a starch-based substance.

[0015] According to an embodiment of the present invention, the bio-based additive comprises the component A. Preferably, the bio-based additive consists of the component A.

[0016] According to an embodiment of the present invention, the bio-based additive comprises the component A and the component B. Preferably, the bio-based additive consists of the component A and the component B.

[0017] According to an embodiment of the present invention, the bio-based additive consists of 5 to 15 parts of component A and 0.1 to 3 parts of component B by weight, preferably the bio-based additive consists of 5 to 15 parts of component A and 0.1 to 3 parts of component B, for example, the bio-based additive consists of 9 parts of component A and 1 part of component B.

[0018] As an example, the component A is a biomass having a dendritic or network structure.

[0019] As another example, the component A is a cationized biomass material having a dendritic or network structure.

[0020] As another example, the component A consists of a biomass material having a dendritic or network structure and a cationized biomass material having a dendritic or network structure.

[0021] According to an embodiment of the present invention, in parts by weight, component A consists of 30 to 60 parts of biomass having a dendritic or network structure or 30 to 60 parts of cationized biomass materials having a dendritic or network structure or a mixture thereof, preferably, component A consists of 40 to 60 parts of biomass having a dendritic or network structure or 50 to 60 parts of cationized biomass materials having a dendritic or network structure or a mixture thereof, for example, component A consists of 50 parts of biomass having a dendritic or network structure or 50 parts of cationized biomass materials having a dendritic or network structure or a mixture thereof.

[0022] According to a preferred embodiment of the present invention, the bio-based additive does not contain a wet strength agent and / or a starch-based substance.

[0023] According to a preferred embodiment of the present invention, the wet strength agent includes but is not limited to PAM (polyacrylamide), PAE (polyamide epichlorohydrin resin), PEI (polyethyleneimine), UF (urea-formaldehyde resin) and the like.

[0024] According to a preferred embodiment of the present invention, the starch material includes but is not limited to tapioca starch, corn starch, pregelatinized starch, oxidized starch, cationic starch, phosphate starch, acetate starch, enzyme hydrolyzed starch, and the like.

[0025] The present invention also provides application of the slurry composition in preparing high-quality paper products.

[0026] As an example, the high-quality paper product is a paper-plastic product.

[0027] According to an embodiment of the present invention, the high-quality paper products include but are not limited to medical paper (e.g. medical crepe paper), analytical and testing paper (e.g. absorbent paper), filter paper (e.g. chromatography paper), and tobacco paper (e.g. tobacco sheet paper).

[0028] As an example, the high-quality paper product is tobacco sheet paper.

[0029] The present invention also provides a method for preparing a high-quality paper product using the above-mentioned slurry composition, comprising the following steps:

[0030] The fiber pure pulp is added into water and fully dispersed, and then the biomass material is added and mixed, and then the mixture is dissociated by a disintegrator to prepare a wet paper blank and dry it to obtain a high-quality paper product.

[0031] According to an embodiment of the present invention, the mass concentration of the pure fiber pulp in water is 0.1%-0.5%, and preferably the mass concentration of the pure fiber pulp in water is 0.2%-0.3%.

[0032] According to an embodiment of the present invention, the dissociation is carried out under stirring conditions, and the stirring speed is 3000 rpm to 8000 rpm, for example, the dissociation is carried out by a dissociator at 5000 rpm to 10000 rpm.

[0033] According to an embodiment of the present invention, the preparing of the wet paper blank is performed using a papermaking machine.

[0034] According to an embodiment of the present invention, the drying is performed under vacuum conditions.

[0035] According to an embodiment of the present invention, the drying temperature is 130-150° C., and the drying time is 10-15 minutes.

[0036] Beneficial Effects

[0037] 1) The present invention adds a bio-based additive to pure fiber pulp. The bio-based additive is selected from one or both of a biomass material with a dendritic or network structure or a cationized biomass material with a dendritic or network structure. The dendritic or network structure in the bio-based additive has a rich micro-nano multi-level structure, which can be overlapped to form a dense network. A large number of hydroxyl groups are distributed on the micro-nano structure. These hydroxyl groups can form hydrogen bonds with cellulose in the pure fiber pulp to form a larger network structure. The paper product prepared by using such a composition has higher strength. At the same time, the hydrogen bonds and hydroxyl groups on the network structure help to intercept water, thereby improving the water absorption of the paper product.

[0038] 2) When preparing tobacco sheet paper in the present invention, after adding bio-based additives, the use of external fibers can be effectively reduced, thereby avoiding the negative effects of wood pulp fibers on the sensory quality of tobacco sheet paper, such as increasing the woodiness of the product, increasing irritation, and worsening the taste. At the same time, the tobacco sheet paper obtained by adding biomass-based additives has better tear index and tensile properties than the product with only the same amount of wood pulp fibers added.

[0039] 3) When preparing filter paper in the present invention, after adding the bio-based additive, the obtained product has good tensile strength, ring crush strength, tear strength, and burst resistance, and the performance is equivalent to that of the product with the same amount of wet strength agent added, thereby avoiding the introduction of non-biodegradable petroleum-based wet strength agent components; at the same time, it can also avoid the clogging of the mold and the sticking film caused by the addition of the wet strength agent, thereby improving the preparation efficiency.

[0040] 4) The slurry composition of the present invention does not need to use wet strength agents and / or starch-based substances, thus avoiding the introduction of new organic matter and more metal ions, and controlling the content of non-paper components from the source. Compared with paper products prepared using wet strength agents and / or starch-based substances, the products prepared using the slurry composition of the present invention have a lower impurity content, especially avoiding the introduction of petroleum-based organic matter.

[0041] 5) The applicant has also unexpectedly discovered that by adding bio-based additives to the pulp, the obtained medical crepe paper has higher strength and better water absorption while avoiding environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is the structure of the biomass material having a dendritic or network structure used in the examples. DETAILED DESCRIPTION

[0043] [Structure of biomass materials with dendritic or network structures]

[0044] The biomass material with a dendritic or network structure includes a micron-scale structure and a nanometer-scale structure distributed on the micron-scale structure.

[0045] According to an embodiment of the present invention, the biomass material with a dendritic or network structure is a regenerated natural polymer (for example, type II cellulose, or a mixture of type II cellulose and type I cellulose), and the regenerated natural polymer includes a micron-scale structure and a nanoscale structure distributed on the micron-scale structure.

[0046] According to an embodiment of the present invention, the size of the micron-scale structure (i.e., the volume average size) is 50μm to 500μm, preferably the size of the micron-scale structure is 50μm to 300μm, and further preferably, the size of the micron-scale structure is 100μm to 200μm, for example, any value among 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, or any point value among the intermediate values ​​formed by any two point values.

[0047] According to an embodiment of the present invention, the length of the nanoscale structure is 50nm to 800nm, preferably the length of the nanoscale structure is 100nm to 500nm, and further preferably, the length of the nanoscale structure is 200nm to 400nm, for example, any value among 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm or any point value in the middle value formed by any two point values.

[0048] According to an embodiment of the present invention, the aspect ratio of the nanoscale structure is 1:1 to 1:150, preferably the aspect ratio of the nanoscale structure is 1:1 to 1:100, more preferably the aspect ratio of the nanoscale structure is 1:10 to 1:100, for example 1:50.

[0049] According to an embodiment of the present invention, the micron-scale structure includes at least one of a micron sheet, a micron fiber, and a micron multi-level structure.

[0050] According to an embodiment of the present invention, the micron-scale structure is in a fiber or film shape, which can also be called fiberization.

[0051] According to an embodiment of the present invention, the nanoscale structures are distributed on the surface and / or edge of the microscale structure. Specifically, the nanoscale structures are densely distributed on the surface and / or edge of the microscale structure.

[0052] According to an embodiment of the present invention, the nano-scale structure is distributed on the micro-scale structure to form a flocculent shape as a whole.

[0053] According to an embodiment of the present invention, the nano-scale structure is distributed on the micro-scale structure to form an overall structure similar to a porous sponge.

[0054] According to an embodiment of the present invention, the nano-scale structure and the micro-scale structure together form a feather-like structure.

[0055] According to an embodiment of the present invention, the nanoscale structure is in the shape of villi, tentacles, whiskers or other irregular structures.

[0056] According to an embodiment of the present invention, the biomass material is in a fibrous, flaky, feathery, branchy, flocculent or porous sponge-like structure.

[0057] [Preparation of biomass materials with dendritic or network structures]

[0058] The preparation method is selected from method 1 or method 2, wherein the method 1 comprises the following steps:

[0059] dissolving the biomass in a solvent to form a biomass solution;

[0060] The biomass solution and the coagulation bath are added to a crushing device, and the two are mechanically crushed while being mixed to prepare the bio-based material; or after the mechanical crushing, the biomass material with a dendritic or network structure is prepared by filtering and washing;

[0061] The second method comprises the following steps: pouring the biomass solution into a coagulation bath to form a biomass gel; and subjecting the biomass gel to micro-nano treatment through mechanical crushing to obtain the biomass material with a dendritic or network structure.

[0062] According to an embodiment of the present invention, the reagent used in the washing step in method one and method two is selected from at least one of water, alcohol, alcohol-water mixture, HCl aqueous solution, NaOH aqueous solution, and inorganic salt aqueous solution, preferably water and / or alcohol, such as water.

[0063] According to an embodiment of the present invention, the biomass is derived from one, two or more of the following substances: cellulose or its derivatives (such as ethyl cellulose, carboxymethyl cellulose, cellulose acetate), starch or its derivatives (such as oxidized starch, modified oil-proof starch), chitosan or its derivatives (such as carboxymethyl chitosan, chitin), and alginate.

[0064] According to an embodiment of the present invention, the biomass is selected from at least one of lignin, glucan, hemicellulose, straw, plant stems and leaves, reeds, bagasse, Chinese medicine residues, tea residues, corn cobs, fruit shells, vines, branches and the like.

[0065] For example, the biomass is selected from at least one of microcrystalline cellulose, bacterial cellulose, lignin, cotton pulp, wood pulp, bamboo pulp, straw pulp, refined cotton, absorbent cotton, cotton linter, bagasse, wood and straw, etc.; preferably one or more of microcrystalline cellulose, refined cotton, absorbent cotton and wood pulp.

[0066] According to an embodiment of the present invention, the solvent for dissolving the biomass can be selected from any good solvent known in the art that can completely dissolve the biomass. Preferably, according to the different types of cellulose or cellulose-containing raw materials, the selected solvent can be selected from one or more of the following systems: organic solvents, ionic liquids, mixed solvents of ionic liquids and organic solvents, choline-type ionic liquid low eutectic solvent systems, organic solvent / salt systems, amine oxide systems (NMMO), carbamate systems, alkali / water systems, alkali / urea systems, alkali / thiourea systems, liquid ammonia / NH4SCN, organic acids, aqueous solutions of metal salts, alcohol solutions of metal salt hydrates, water-alcohol mixed solutions of metal salt hydrates, and other solvent systems.

[0067] According to an embodiment of the present invention, the coagulation bath is selected from at least one of water, alcohol, alcohol-water mixture, HCl aqueous solution, NaOH aqueous solution, and inorganic salt aqueous solution, preferably water and / or alcohol, such as water.

[0068] For example, the biomass material can be obtained by the preparation method described in the patent document application with application number 202310481795.1.

[0069] [Cationized biomass materials with dendritic or network structures]

[0070] According to an embodiment of the present invention, the cationized biomass material structure having a dendritic or network structure modified by an organic amine substance containing a halogenated hydrocarbon group or an epoxy group has a rich micro-nano multi-level structure, can be grafted to form a dense network at a certain temperature and time, and a large number of hydroxyl groups are distributed on the micro-nano structure to form a larger network structure.

[0071] [Preparation of cationized biomass materials with dendritic or network structures]

[0072] A biomass material solution with a dendritic or network structure is added to an alkaline aqueous solution, stirred and dissolved to obtain a biomass alkaline solution, an alcohol organic solvent is added to the biomass alkaline solution to dissolve, a cationic etherifying agent is added to carry out a grafting reaction, and washed to obtain a cationic biomass material with a dendritic or network structure.

[0073] According to an embodiment of the present invention, the alkaline aqueous solution is selected from a NaOH aqueous solution and / or a KOH aqueous solution, and the concentration of the alkaline aqueous solution is 0.1% to 3%.

[0074] According to an embodiment of the present invention, the mass concentration of the biomass having a dendritic or network structure in the alkaline solution is 2% to 10%.

[0075] According to an embodiment of the present invention, the biomass having a dendritic or network structure is reacted in an alkaline solution at a temperature of 30 to 60° C. and a reaction time of 1 to 5 hours.

[0076] According to an embodiment of the present invention, the mass ratio of the biomass alkali solution to the etherifying agent alcohol solution is 1:0.5 to 1:3.

[0077] According to an embodiment of the present invention, the cationic etherifying agent is selected from organic amine salts containing halogenated hydrocarbon groups or epoxy groups, for example, one or more of 3-chloro-2-hydroxypropyl-trimethylammonium chloride and epoxypropyltrimethylammonium chloride.

[0078] According to an embodiment of the present invention, the alcohol organic solvent is a composite solvent of one or more of methanol, ethanol and isopropanol.

[0079] According to an embodiment of the present invention, the temperature of the grafting reaction is 25 to 75° C., and the reaction time is 6 to 48 hours.

[0080] According to an embodiment of the present invention, the grafting reaction is carried out under stirring conditions.

[0081] The composition and application of the present invention will be further described in detail below in conjunction with specific examples. It should be understood that the following examples are only exemplary descriptions and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.

[0082] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0083] In the following examples, the preparation methods of the biomass material having a dendritic or network structure and the cationized biomass material having a dendritic or network structure in the slurry composition are as follows:

[0084] The preparation method of biomass material with dendritic or network structure is as follows: adding a biomass material solution with dendritic or network structure and a coagulation bath into a crushing device, and mechanically crushing the two while mixing them to prepare the bio-based material; or filtering and washing after mechanical crushing to prepare the biomass material.

[0085] Preparation method of cationic biomass material with dendritic or network structure:

[0086] a) adding a biomass material solution having a dendritic or network structure into an alkaline aqueous solution, such as an aqueous solution of NaOH or KOH, stirring and dissolving, and obtaining a biomass alkaline solution.

[0087] b) adding glycidyl trimethyl ammonium chloride in a mass ratio of 1:1 between the absolute dry weight of the cationized biomass material with a dendritic or network structure and glycidyl trimethyl ammonium chloride, adding an appropriate amount of isopropanol to dissolve it, to obtain an isopropanol solution of glycidyl trimethyl ammonium chloride, and adding the solution in step a) to react, for example, at room temperature for 24 hours.

[0088] c) After the reaction is completed, the biomass material is washed with deionized water until it becomes neutral, thereby obtaining a cationic biomass material having a dendritic or network structure.

[0089] According to an embodiment of the present invention, the concentration of the alkaline aqueous solution is 0.1% to 3%.

[0090] According to an embodiment of the present invention, the mass concentration of the biomass having a dendritic or network structure in the alkaline solution is 2% to 10%.

[0091] According to an embodiment of the present invention, the mass ratio of the biomass alkali solution to the etherifying agent alcohol solution is 1:0.5 to 1:3.

[0092] The properties of the prepared pulp product were measured as follows:

[0093] GB / T 2679.8-2016 Determination of ring crush strength of paper and paperboard;

[0094] GB / T 455-2002 Paper and paperboard tear resistance test standard;

[0095] GB / T 1539-2007 Test standard for bursting strength of paperboard;

[0096] GB / T 12914-2008 Standard for determination of tensile strength of paper and paperboard.

[0097] Preparation of the biomass material with a dendritic or network structure used in the following examples: 5 parts of cotton pulp were dissolved in 95 parts of 1-allyl-3-methylimidazolium chloride, and stirred at 70°C for 6 hours to form a biomass solution. The biomass solution and 50 parts of water were added to a crushing device, and the two were mechanically crushed while mixing. The ionic liquid was filtered and washed to prepare a biomass material with a solid content of 2.5% and a size of 10μm to 50μm with a dendritic or network structure, see Figure 1 Shown is a SEM image of a biomass material having a dendritic or network structure.

[0098] Preparation of the cationic biomass material with dendritic or network structure used:

[0099] 2.5 parts of the biomass material with a dendritic or network structure prepared as above were added to 195 parts of a 0.12% NaOH aqueous solution, stirred at room temperature for 1 hour to obtain an alkaline dispersion of the biomass, 15 parts of anhydrous ethanol were added to the alkaline dispersion of the biomass, and then 2.5 parts of 2,3-epoxypropyltrimethylammonium chloride were added, and the mixture was stirred at 60°C for 6 hours. After the reaction was completed, the mixture was washed with water until neutral to obtain a cationic biomass material with a dendritic or network structure having a solid content of 1.2% and a size of 10μm to 50μm.

[0100] Example 1 Preparation of paper products (filter paper) using bamboo pulp as pure fiber pulp

[0101] In this embodiment, bamboo pulp comes from Sichuan Huanlong New Materials Co., Ltd. and is prepared by chemical method. The characteristic of bamboo pulp is that the fiber is slender. When it is used alone for the production of pulp products, the obtained pulp products will have the disadvantages of low density and easy fuzzing on the surface. In view of this situation, this embodiment adds bio-based additives to improve the performance of paper products.

[0102] As shown in Table 1, the following preparation method is adopted to select different bio-based additives (biomass materials with dendritic or network structures and / or cationized biomass materials with dendritic or network structures) to prepare pulp products.

[0103] A method for preparing a paper product comprises the following steps:

[0104] S1. The natural pure bamboo pulp produced by chemical method is dissociated by a fiber disintegrator at 5000 revolutions to fully disintegrate and evenly disperse the bamboo pulp fibers to a beating degree of about 22°SR, and water is added to prepare a pulp mixture having a bamboo pulp fiber content of 0.3 wt% for standby use.

[0105] S2. According to schemes 1-5 in Table 1, corresponding mass parts (96 parts, 96 parts, 96 parts, 96 parts, 96 parts) of 0.3wt% of pulp mixture, (0 parts, 4 parts, 0 parts, 2 parts, 0 parts) of biomass material with a dendritic or network structure, and (0 parts, 0 parts, 4 parts, 2 parts, 0 parts) of cationized biomass material with a dendritic or network structure are dissociated by a dissociator, and then a wet paper blank is made using a papermaking machine, the wet paper blank is placed in a hot pressing mold, and dried at 140°C for 10 min under vacuum to obtain a paper product.

[0106] According to the above preparation method, a paper product was processed into a mold, and a group (Scheme 1) without adding the bio-based composition component was set as a blank sample, and a group (Scheme 5) without adding the bio-based composition component but adding 1.5 parts

[0107] The solution of wet strength agent PAM is used as a comparative example.

[0108] Table 1 Bamboo pulp composition with different bio-based additives

[0109]

[0110] The physical properties of paper products prepared using the bamboo pulp composition in Table 1 are shown in Table 2 below. As can be seen from Table 2, the addition of bio-based additives greatly improves the physical strength of pure bamboo chemical pulp products, and the improvement is much higher than the enhancement effect of conventional wet strength agents (PAM dosage 1.5%).

[0111] This result can be used as a reference for enterprises to use pure bamboo chemical pulp alone to produce paper products and improve their strength.

[0112] Table 2 Physical properties of paper products prepared with different pulp compositions

[0113]

[0114]

[0115] Example 2 Preparation of paper products (tobacco sheet paper) using tobacco pulp as pure fiber pulp

[0116] The pulp for preparing tobacco sheet paper is usually tobacco pulp made from tobacco stems and tobacco dust, which has a low fiber content and low bonding strength when formed into paper, and cannot meet the requirements of papermaking, so additives need to be added. However, due to the high performance requirements of tobacco sheet paper, the safety requirements for additives are also high, which greatly limits the selection and application range of additives such as enhancers for tobacco sheet paper. In order to ensure the stable operation of the paper machine, the traditional papermaking process for producing tobacco sheet paper solves these problems by adding wood pulp fibers as additives. However, while adding wood pulp fibers improves the physical strength of tobacco sheet paper and ensures the stable operation of the paper machine, it will inevitably have a certain negative impact on the sensory quality of tobacco sheet paper, such as increasing the wood smell of the product, increasing irritation, and worsening the taste.

[0117] The tobacco slurry in this example comes from Yantai Guangrui Chemical Technology Co., Ltd.

[0118] In this example, bio-based additives were added during the production of tobacco sheet paper by a traditional papermaking method to investigate the effects of the bio-based additives on the physical properties of the tobacco sheet paper.

[0119] Table 3 Tobacco slurry composition with different bio-based additives

[0120]

[0121] Preparation method of tobacco pulp:

[0122] 100 g of tobacco raw material (50 g of tobacco stems and 50 g of tobacco dust) was added into 1000 mL of water and extracted at 50°C for 1 h. After solid-liquid separation, the solid phase was ground into tobacco pulp with a beating degree of (25±2)°SR by a high-concentration refiner for later use.

[0123] Tobacco sheet production:

[0124] The prepared tobacco pulp, wood pulp fiber, bio-based additives, guar gum and light CaCO3 were mixed according to the proportion of the tobacco slurry composition in Table 3, and a fast sheet former was used to form a paper sheet with a basis weight of 60 g / m 2 Handmade sheets, i.e. tobacco sheet paper.

[0125] Table 4 Physical properties of different tobacco thin papers

[0126]

[0127] From the data in Table 4, it can be seen that the addition of bio-based additives greatly improves the physical strength of tobacco sheet paper and reduces the amount of wood pulp fiber, thereby improving the problem of tobacco irritating odor and taste, that is, while meeting the product strength requirements and ensuring the stable operation of the paper machine, the amount of wood pulp fiber is reduced (for example, in 3#, 5#, and 7#, the amount of wood pulp fiber is significantly reduced from 15 parts to 13 parts, 11 parts, and 9 parts, but the tear index and tensile properties of the obtained product are better than those of 1# which only adds 15 parts of wood pulp fiber and does not add bio-based composition), which is conducive to solving the problem of heavy wood smell in tobacco sheets, thereby improving product quality.

[0128] Example 3 Preparation of paper products (medical crepe paper) using fiber raw materials as fiber pure pulp

[0129] Medical crepe paper is a packaging material used for trolleys, operating room tables and sterile area drapes. Since medical crepe paper rarely contains other additives (such as reinforcing agents, water repellents, oil repellents, coatings, etc.) except softeners, the medical crepe paper on the market has the disadvantage of low strength.

[0130] In this embodiment, bamboo pulp is used as pure fiber pulp to prepare paper products, and the bamboo pulp comes from Sichuan Huanlong New Materials Co., Ltd.

[0131] In this example, bio-based additives were added during the pulp production process, as shown in Table 5, to examine the influence of the bio-based composition on physical properties, thereby improving production efficiency while meeting product performance requirements and ensuring stable production operation.

[0132] Table 5 Slurry composition with different bio-based additives

[0133]

[0134] Medical crepe paper preparation process:

[0135] (1) Using a fiber disintegrator, the natural pure bamboo pulp produced by the chemical method was disintegrated for 5000 revolutions to fully disintegrate and disperse the bamboo pulp fibers evenly to a beating degree of about 22°SR, and water was added to prepare a pulp mixture with a bamboo pulp fiber content of 0.3wt% for standby use. Bio-based additives and polyoxyethylene stearate were added in sequence according to the proportions in Table 5, wherein the step of adding polyoxyethylene stearate is: polyoxyethylene stearate was diluted with water to 0.1wt% and then continuously and evenly added to the pulp mixture at the outlet of the slurry pump within 5 minutes to obtain a slurry.

[0136] (2) The slurry is dehydrated, formed and pressed through a headbox. When the dryness of the paper sheet is 30%, the wet-cylinder creping is performed. During the wet-cylinder creping process, the moisture content of the paper sheet out of the vat is controlled to be 60%. The thickness of the scraper blade is 0.8 mm, and the angle between the scraper and the vat is 7°. The paper is then dried to obtain medical crepe paper.

[0137] Table 6 Physical properties of medical crepe paper prepared with different slurry compositions

[0138]

[0139] As can be seen from Table 6, the addition of bio-based additives improves the tensile strength of paper products, thereby avoiding the problem of low strength caused by the fact that very few additives such as reinforcing agents are added to medical crepe paper, while also avoiding environmental pollution.

[0140] Comparative Example 1

[0141] A company uses natural or bleached bamboo pulp to produce fine industrial paper products, and often receives customer complaints about insufficient product strength. To this end, the company has tried a variety of process measures, such as adding modified starch as internal sizing; adjusting the pulp ratio, such as changing the ratio of bamboo pulp and bagasse pulp, or adding a certain proportion of coniferous wood pulp; improving the pulp beating degree by refining; adding PAE as a wet strength agent; increasing the pressure of the wet press; spraying varnish on the surface, etc. However, the use of modified starch in combination with AKD for in-slurry sizing will cause mold clogging and sticking problems and is forced to be cancelled; the addition of a large amount of wet strength agent will cause mold clogging and sticking problems and is forced to reduce the dosage; the range of increasing the wet press pressure is very limited, and it is easy to accelerate equipment wear or cause other problems; surface spraying of varnish is difficult because of the high price of varnish and the large amount used, the insufficient degree of automation of the spraying equipment, low production efficiency, and the difficulty in achieving clean production during the spraying process, resulting in a large proportion of waste, resulting in high overall costs and making it difficult to use in actual production; the above defects result in the existing measures not only failing to effectively solve the problems, but also causing new production problems due to process adjustments, which not only cause more production quality fluctuations, but also indirectly reduce production efficiency and increase costs.

[0142] As shown in Examples 1-3, the present invention only adds bio-based additives, adjusts the pulp type ratio, refines the pulp, adds a small amount of wet strength agent or does not add any other adjustments, and performs production without affecting other production factors and production suitability. It can effectively improve the physical properties of paper products, and the improvement effect is better than using wet strength agents, refining, and adding 10% of coniferous wood pulp.

[0143] Comparative Example 2

[0144] A paper and plastic enterprise mainly produces analytical extraction filter elements, medical filtration equipment filter elements, food and drug filtration equipment and other paper products. These products have extremely high requirements for the purity of raw materials. The addition of any chemical substances may interfere with the results of scientific research analysis or pose a migration risk to the food and drug production process. Therefore, during the production process, the enterprise dared not use non-fiber chemicals to improve the strength index, and has long been troubled by insufficient product strength.

[0145] After using the products provided by our company, we obtained satisfactory application results.

[0146] The above examples are used to illustrate the specific implementation of the present invention. However, the protection scope of the present invention is not limited to the above exemplary implementation. Any modification, equivalent substitution, improvement, etc. made by those skilled in the art within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A pulp composition for high-quality paper products, characterized in that: The slurry composition includes pure fiber slurry and bio-based additives; Wherein, the bio-based additives include: Component A: one or both of a biomass material having a dendritic or network structure or a cationized biomass material having a dendritic or network structure; Optionally contain or not contain component B: one, two or more selected from polyhydroxyalkanoates, alkyl ketene dimers, polyglycolide, polylactide, copolymers of butylene adipate and butylene terephthalate, polyoxyethylene stearate, cellulose esters and cellulose ethers.

2. The pulp composition for high-quality paper products according to claim 1, characterized in that: The slurry composition comprises 90 to 100 parts of pure fiber pulp and 1 to 10 parts of bio-based additives by weight. Preferably, the pure fiber pulp includes but is not limited to one or a mixture of wood pulp, straw pulp, bamboo pulp or bagasse pulp pure fiber pulp.

3. The pulp composition for high-quality paper products according to claim 1, characterized in that: The bio-based additive comprises the component A and the component B. Preferably, the bio-based additive consists of the component A and the component B. Preferably, the bio-based additive consists of 5 to 15 parts of component A and 0.1 to 3 parts of component B by weight.

4. The pulp composition for high-quality paper products according to any one of claims 1 to 3, characterized in that: In terms of weight, the component A is composed of 30 to 60 parts of biomass with a dendritic or network structure or 30 to 60 parts of cationic biomass materials with a dendritic or network structure or a mixture thereof.

5. Use of the slurry composition according to any one of claims 1 to 4 in the preparation of high-quality paper products. Preferably, the high-quality paper product is a paper-plastic product.

6. The use according to claim 5, characterized in that: The high-quality paper products include, but are not limited to, medical paper (such as medical crepe paper), analysis and testing paper (such as absorbent paper), filter paper (such as chromatography paper), and tobacco paper (such as tobacco sheet paper).

7. A method for preparing high-quality paper products using the slurry composition according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: adding pure fiber pulp into water and fully dispersing it, adding biomass material and mixing it, dissociating it through a dissociator, preparing wet paper blanks and drying them to obtain high-quality paper products.

8. The method for preparing a high-quality paper product according to claim 7, characterized in that: The mass concentration of the pure fiber pulp in water is 0.1%-0.5%, and preferably the mass concentration of the pure fiber pulp in water is 0.2%-0.3%.

9. The method for preparing a high-quality paper product according to claim 7, characterized in that: The dissociation is carried out under stirring conditions, and the stirring speed is 3000 rpm to 8000 rpm.

10. The method for preparing a high-quality paper product according to any one of claims 7 to 9, characterized in that: The drying is carried out under vacuum conditions, the drying temperature is 130-150° C., and the drying time is 10-15 minutes.

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