Styrene acrylate copolymer modified paper-based facing material and preparation method thereof

Abstract

The invention provides a styrene acrylate copolymer modified paper-based facing material and a preparation method thereof.The preparation method comprises the steps that S100, raw materials including a wet strength agent, aluminum sulfate, cationic polyacrylamide, silicon dioxide particles, wood pulp and water are adopted, and raw paper is prepared; s200, mixing raw materials including kaolin, calcium carbonate, a styrene acrylate copolymer and water to prepare a sizing agent; s300, sizing raw paper by adopting a sizing agent, drying and calendaring to obtain a paper-based facing material; wherein the styrene-acrylate copolymer comprises acrylic acid, ethyl acetate, butyl acetate, methylbenzene, methyl acrylate, butyl acrylate and styrene. The paper-based facing material which is resistant to water and moisture and good in whiteness and concealing force can be obtained.

Description

Technical Field

[0001] The invention relates to the technical field of papermaking, and in particular to a styrene acrylate copolymer-modified paper-based facing material and a preparation method thereof. Background Art

[0002] Paper-based finishing materials are a type of industrial specialty paper processed through a special process. They are also an indispensable raw material in many building materials products, such as low-pressure boards and high-pressure boards used in furniture and cabinets, as well as fireproof boards, floors, wallpapers, etc., which all require paper-based finishing materials to enhance the aesthetics of the products.

[0003] Paper-based facing materials are usually manufactured through pulping, papermaking, pressing, sizing, etc. The sizing process can prevent or reduce the penetration of water or other aqueous liquids into the paper, so the sizing process is an important process in the manufacturing process of paper-based facing materials.

[0004] How to improve the water and moisture resistance of paper-based facing materials by preparing suitable sizing agent components is one of the technical problems that those skilled in the art need to solve. Summary of the invention

[0005] One of the problems solved by the present invention is how to provide a paper-based facing material with good water and moisture resistance.

[0006] In order to solve at least one of the above problems, the present invention provides a method for preparing a styrene acrylate copolymer-modified paper-based facing material, the preparation method comprising:

[0007] S100, preparing base paper using raw materials including a wet strength agent, aluminum sulfate, cationic polyacrylamide, silica particles, bleached coniferous wood pulp, bleached hardwood wood pulp and water;

[0008] S200, mixing raw materials including kaolin, calcium carbonate, starch, styrene acrylate copolymer and water to prepare a sizing agent;

[0009] S300, sizing the base paper with a sizing agent, drying and calendering to obtain a paper-based facing material.

[0010] In any of the above technical solutions, the styrene acrylate copolymer includes: acrylic acid, ethyl acetate, butyl acetate, toluene, methyl acrylate, butyl acrylate, and styrene.

[0011] In any of the above technical solutions, based on the total amount of the styrene acrylate copolymer being 100 parts by mass, the styrene acrylate copolymer comprises:

[0012] Acrylic acid, 1 to 2 parts by mass;

[0013] Ethyl acetate, 6 to 8 parts by mass;

[0014] Butyl acetate, 8 to 10 parts by mass;

[0015] Toluene, 10 to 12 parts by mass;

[0016] Methyl acrylate, 12 to 14 parts by mass;

[0017] Butyl acrylate, 28 to 30 parts by mass;

[0018] Styrene: 30 to 32 parts by mass.

[0019] In any of the above technical solutions, S100 specifically includes:

[0020] S110, mixing raw materials including a wet strength agent, aluminum sulfate, cationic polyacrylamide, silicon dioxide, bleached coniferous wood pulp and bleached hardwood wood pulp to obtain pulp;

[0021] S120, placing the pulp on a screen to make paper, to obtain wet paper sheets;

[0022] S130, pressing and drying the wet paper sheets to obtain base paper.

[0023] In any of the above technical solutions, the mass ratio of wet strength agent: aluminum sulfate: cationic polyacrylamide: silicon dioxide: bleached coniferous wood pulp: bleached broadleaf wood pulp is (3-4): (4-5): (5-6): (12-16): (15-25): 100.

[0024] In any of the above technical solutions, S200 specifically includes:

[0025] S210, mixing kaolin, calcium carbonate, starch and styrene acrylate copolymer in water to prepare a slurry;

[0026] S220, shearing and mixing the slurry uniformly to prepare a sizing agent.

[0027] In any of the above technical solutions, the mass ratio of kaolin: calcium carbonate: starch: styrene acrylate copolymer: water is (5-10): (10-15): (15-20): (100-120): (250-350).

[0028] In any of the above technical solutions, the starch is enzymatically hydrolyzed starch that has been enzymatically hydrolyzed using α-amylase.

[0029] In any of the above technical solutions, calcium carbonate contains titanium dioxide.

[0030] The present invention also provides a styrene acrylate copolymer modified paper-based facing material, and the styrene acrylate copolymer modified paper-based facing material is obtained by using the preparation method of any of the above technical solutions.

[0031] Beneficial Effects

[0032] The invention provides a method for preparing a paper-based facing material modified by a styrene acrylate copolymer. The method firstly adopts raw materials including a wet strength agent, aluminum sulfate, cationic polyacrylamide, silica particles, bleached coniferous wood pulp, bleached broadleaf wood pulp and water to prepare base paper; then, raw materials including kaolin, calcium carbonate, starch, styrene acrylate copolymer and water are mixed to prepare a sizing agent; finally, the base paper is sizing by the sizing agent, and the base paper is dried and calendered to obtain the paper-based facing material. The sizing agent of the invention contains a styrene acrylate copolymer. Styrene acrylate copolymer (SA copolymer for short) is a polymer material prepared by copolymerization of styrene and acrylate monomers. It is characterized by being easy to form a film, and the film layer is smooth, delicate and has strong adhesion. The dispersion of the styrene acrylate copolymer in water has the characteristics of high viscosity and high thixotropy, and has uniform particle size, strong adhesion and good stability. The sizing agent prepared by the styrene acrylate copolymer can improve the water and moisture resistance of the paper-based facing material. In addition, kaolin and calcium carbonate can also improve the whiteness and hiding power of paper. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the following is a detailed description of the specific embodiments of the present invention.

[0034] Unless otherwise specified, the reagents and raw materials used in the present invention can be purchased through commercial channels. The experimental methods in the following examples without specifying specific conditions are selected according to conventional methods and conditions, or according to the product specifications.

[0035] Paper-based finishing materials can be used in a variety of application scenarios such as furniture veneer and wallpaper. Water and moisture resistance is one of the important properties to measure the quality of paper-based finishing materials. How to improve the water and moisture resistance of paper-based finishing materials has always been a technical problem that technicians in this field are committed to solving.

[0036] In order to solve the above problems, an embodiment of the present invention provides a method for preparing a styrene acrylate copolymer modified paper-based facing material, the preparation method comprising:

[0037] S100, preparing base paper using raw materials including a wet strength agent, aluminum sulfate, cationic polyacrylamide, silica particles, bleached coniferous wood pulp, bleached hardwood wood pulp and water;

[0038] S200, mixing raw materials including kaolin, calcium carbonate, starch, styrene acrylate copolymer and water to prepare a sizing agent;

[0039] S300, sizing the base paper with a sizing agent, drying and calendering to obtain a paper-based facing material.

[0040] The above technical solution is suitable for preparing interior decoration paper such as furniture veneer, wallpaper, etc. The paper-based facing material of the present invention is mainly manufactured by pulping, papermaking, pressing, gluing and other processes. Those skilled in the art can select and adjust the equipment, raw materials and process parameters used in pulping, papermaking, pressing and gluing according to actual needs.

[0041] Pulping is a key process in the papermaking industry, which separates the fibers from the plant fiber raw materials to obtain paper pulp. The pulping step of the present invention can be carried out by mechanical method, chemical method or chemical mechanical method. The papermaking step uses a bamboo curtain type mesh trough specially used for papermaking to scoop a certain amount of paper pulp, and then swings the mesh trough back and forth or left and right to arrange the pulp fibers in a certain direction to form a paper layer of uniform thickness, i.e., wet paper sheet. The pressing process squeezes the wet paper through a press, which removes excess water from the paper layer and increases the dryness of the paper. The pressure and speed in the pressing process can be selected and adjusted by those skilled in the art according to actual needs.

[0042] It can be understood that the process of using pulp to make paper on the net and press to obtain base paper is a relatively mature existing technology. The selection of specific process parameters for making paper on the net and pressing has no substantial impact on the realization of the purpose of the present invention.

[0043] Preferably, the beating degree of the wood pulp used in S100 is 30°SR to 45°SR.

[0044] In the above technical solution, S100 specifically includes:

[0045] S110, mixing raw materials including a wet strength agent, aluminum sulfate, cationic polyacrylamide, silicon dioxide, bleached coniferous wood pulp and bleached hardwood wood pulp to obtain pulp;

[0046] S120, placing the pulp on a screen to make paper, to obtain wet paper sheets;

[0047] S130, pressing and drying the wet paper sheets to obtain base paper.

[0048] Preferably, in terms of mass ratio, wet strength agent: aluminum sulfate: cationic polyacrylamide: silicon dioxide: bleached coniferous wood pulp: bleached hardwood wood pulp = (3-4): (4-5): (5-6): (12-16): (15-25): 100.

[0049] Further preferably, in terms of mass ratio, wet strength agent: aluminum sulfate: cationic polyacrylamide: silicon dioxide: bleached coniferous wood pulp: bleached hardwood wood pulp = 3:4:6:15:25:100.

[0050] Among them, the role of the wet strength agent is to significantly improve the wet strength of the paper without changing the dry strength of the paper, so that the paper can still maintain good physical properties in a humid environment. Preferably, the present invention can select PAE wet strength agent. The addition of aluminum sulfate can significantly improve the hardness and strength of the paper, enhance the water resistance of cellulose, and thus improve the quality and durability of the paper. In addition, the use of aluminum sulfate can improve the gloss and smoothness of the paper. Cationic polyacrylamide reduces surface tension through the carboxyl group in its molecular chain, so that the fiber or filler is better dispersed in water, thereby improving the uniformity and quality of the paper. Silicon dioxide is used as a filler, which can improve the mechanical strength and fireproof and heat-insulating properties of the paper.

[0051] Exemplarily, the silicon dioxide used in the present invention can be prepared by the following steps:

[0052] S111, mixing chitosan in ethanol and water at a mass ratio of chitosan: ethanol: water = (8-12): (25-30): 100, adding acid to adjust the pH value to 3-4, to obtain liquid A;

[0053] S112, adding silicon tetrachloride to liquid A according to the mass ratio of silicon tetrachloride: water = (4-8): 100 and the amount of water added in S111, stirring simultaneously, continuing stirring for 1h to 1.5h after the addition is completed, adding alkali to adjust the pH value to 11-12, and standing for 12h to 15h to obtain a silica sol containing chitosan;

[0054] S113. Soak the silica sol in ethanol and age it for 24 to 48 hours, take it out and put it into a vacuum reactor filled with ethanol, and keep it warm and pressurized for 2 to 3 hours at a temperature of 260°C to 270°C and a pressure of 6.7MPa to 7.0MPa. After the treatment, cool and release the pressure, separate, wash with water, and dry to obtain silica.

[0055] The purpose of adopting the above steps is to prepare loose and porous, hollow inside, small particle size and uniform particle size distribution of silicon dioxide particles. In general, the above steps adopt the sol-gel method to prepare nano silicon dioxide. The improvement made on the basis of the existing sol-gel method is that chitosan is added to the water-alcohol liquid used to prepare the sol solution. The water-alcohol liquid of nano silicon dioxide prepared by the sol-gel method needs to add an acid catalyst, and chitosan has low solubility in water under acidic conditions and exists almost in a particle state. Subsequently, in order to prepare nano silicon dioxide, it is also necessary to add an alkaline catalyst, and chitosan has increased solubility in water under alkaline conditions, so in the process of adding silicon tetrachloride to liquid A, stirring and adding alkali to adjust the pH value, a silicon dioxide sol containing chitosan can be formed, and chitosan is evenly distributed in the silicon dioxide sol. Subsequently, ethanol is used as a solvent, and aerogel-shaped silicon dioxide can be prepared by supercritical drying. Moreover, chitosan evenly distributed in the silica sol is thermally decomposed at a temperature of 260°C to 270°C, and the decomposed organic matter and water are extracted by supercritical ethanol, thereby forming hollow silica particles that are loose and porous, hollow inside, small in size, and uniform in particle size distribution. The three-dimensional porous and hollow inside properties of the hollow silica particles can improve the fireproof and heat-insulating properties of the base paper.

[0056] The purpose of sizing is to enhance the anti-permeability of the paper-based facing material so that the paper-based facing material can better resist the penetration of liquids such as water and grease, thereby keeping it dry and neat. In addition, the sizing agent can form a protective film on the surface of the paper-based facing material, which helps to prevent it from tearing and wrinkling, thereby improving the strength and stability of the paper. The present invention selects a surface sizing method for sizing, that is, spraying a thin layer of sizing agent on the surface of the paper-based facing material to form a protective film on the surface of the base paper. The surface sizing process of the present invention is carried out on a papermaking machine.

[0057] In any of the above technical solutions, the styrene acrylate copolymer includes: acrylic acid, ethyl acetate, butyl acetate, toluene, methyl acrylate, butyl acrylate, and styrene. Specifically, based on the total amount of styrene acrylate copolymer as 100 parts by mass, the styrene acrylate copolymer includes: acrylic acid, 1 to 2 parts by mass; ethyl acetate, 6 to 8 parts by mass; butyl acetate, 8 to 10 parts by mass; toluene, 10 to 12 parts by mass; methyl acrylate, 12 to 14 parts by mass; butyl acrylate, 28 to 30 parts by mass; styrene, 30 to 32 parts by mass. The characteristics of styrene acrylate copolymer are easy film formation, smooth and delicate film layer, strong adhesion, and dispersion of styrene acrylate copolymer in water has the characteristics of high viscosity and high thixotropy, and uniform particle size, strong bonding force, and good stability. The sizing agent prepared with styrene acrylate copolymer can improve the water and moisture resistance of paper-based finishing materials.

[0058] In any of the above technical solutions, S200 specifically includes:

[0059] S210, mixing kaolin, calcium carbonate, starch and styrene acrylate copolymer in water to prepare a slurry;

[0060] S220, shearing and mixing the slurry uniformly to prepare a sizing agent.

[0061] In any of the above technical solutions, the mass ratio of kaolin: calcium carbonate: starch: styrene acrylate copolymer: water is (5-10): (10-15): (15-20): (100-120): (250-350).

[0062] In any of the above technical solutions, the starch is enzymatically hydrolyzed starch after enzymatic hydrolysis with α-amylase. Specifically, the specific method of enzymatic hydrolysis with α-amylase is as follows: S211, α-amylase and starch are mixed and sent into a reactor, 2 to 2.5 times the mass of starch is added with water, and the mixture is reacted for 20 to 30 minutes at a temperature of 75 to 85°C and a pressure of 40000 Pa to 55000 Pa, and the solids are extracted and dried at a temperature of 120 to 130°C to obtain enzymatically hydrolyzed starch; wherein, based on the amount of starch added, the amount of α-amylase used is 200 ppm to 400 ppm.

[0063] Preferably, the calcium carbonate used in the above steps contains titanium dioxide. Kaolin and calcium carbonate are used to improve the whiteness and hiding power of paper. One of the improvements made by the present invention over the prior art is to load titanium dioxide on calcium carbonate, so that the calcium carbonate containing titanium dioxide enables the paper to achieve an anti-ultraviolet effect. The calcium carbonate filler used in the present invention is prepared by the following steps:

[0064] S221, mixing titanium tetrachloride and calcium carbonate in water and stirring to obtain a first mixture;

[0065] S222, mixing sodium dodecylbenzene sulfonate and sodium hydroxide in water and stirring to obtain a second mixture;

[0066] S223, mixing the first mixture and the second mixture to react to obtain calcium carbonate.

[0067] Optionally, in S221, the mass ratio of titanium tetrachloride:calcium carbonate:water=(4-6):(14-16):100.

[0068] Optionally, in S222, the mass ratio of sodium dodecylbenzenesulfonate:sodium hydroxide:water=(0.5-1):(4-8):100.

[0069] Preferably, in S222, the mass ratio of sodium dodecylbenzene sulfonate: sodium hydroxide: water is 1:5:100.

[0070] In the present invention, S223 specifically includes:

[0071] The second mixture is added dropwise into the first mixture with stirring until the pH value is 10-11. After the addition is completed, the mixture is allowed to stand for 20 to 30 minutes, the solids are filtered, washed, dried, and heat treated at a temperature of 650 to 680° C. for 1 to 1.5 hours to obtain calcium carbonate.

[0072] Through the above steps, the present invention first mixes titanium tetrachloride and calcium carbonate in water to obtain a first mixture. Then, sodium dodecylbenzene sulfonate and sodium hydroxide as surfactants are mixed and stirred in water to obtain a second mixture as an alkaline solution. By dropping the second mixture into the first mixture and stirring it simultaneously, and letting it stand after the dropwise addition is completed, titanium tetrachloride can produce titanium hydroxide under alkaline conditions, and a titanium hydroxide coating layer is deposited on the surface of calcium carbonate. Finally, the present invention oxidizes titanium hydroxide to titanium dioxide through heat treatment at a temperature of 650°C to 680°C. Compared with directly adding nano titanium dioxide to the sizing agent, the advantage of the above steps is that it can avoid the agglomeration of nano-scale titanium dioxide with smaller particle size in the sizing agent, ensuring that a better and more efficient anti-ultraviolet effect is achieved with a smaller amount of titanium dioxide.

[0073] Example 1

[0074] This embodiment provides a styrene acrylate copolymer modified paper-based facing material, which is prepared by the following steps:

[0075] S1. Mix chitosan in ethanol and water at a mass ratio of chitosan: ethanol: water = 10:30:100, add acid to adjust the pH value to 3-4, and obtain liquid A;

[0076] S2, according to the mass ratio of silicon tetrachloride: water = 6:100, according to the amount of water added in S1, silicon tetrachloride was added to liquid A and stirred simultaneously, and after the addition was completed, stirring was continued for 1.5 hours, and alkali was added to adjust the pH value to 11-12, and the mixture was allowed to stand for 12 hours to obtain a silica sol containing chitosan;

[0077] S3, immersing the silica sol in ethanol and aging it for 24 hours, taking it out and sending it into a vacuum reactor filled with ethanol, keeping it warm and pressurized for 2 hours at a temperature of 265° C. and a pressure of 6.8 MPa, cooling and releasing the pressure after the treatment, separating, washing with water, and drying to obtain silica;

[0078] S4, mixing titanium tetrachloride and calcium carbonate in water at a mass ratio of titanium tetrachloride: calcium carbonate: water = 5:15:100 to obtain a first mixture;

[0079] S5, mixing sodium dodecylbenzene sulfonate and sodium hydroxide in water in a mass ratio of sodium dodecylbenzene sulfonate: sodium hydroxide: water = 1:5:100, to obtain a second mixture;

[0080] S6, adding the second mixture dropwise into the first mixture and stirring simultaneously until the pH value is 10-11, adjusting and standing for 20 minutes after the addition is completed, filtering the solids, washing, drying, and heat treating at a temperature of 660° C. for 1.5 hours to obtain calcium carbonate;

[0081] S7, mixing α-amylase and starch into a reactor, adding water twice the mass of starch, reacting for 20 min at a temperature of 80° C. and a pressure of 50000 Pa, extracting solids and drying at a temperature of 125° C. to obtain enzymolyzed starch; wherein the amount of α-amylase used is 200 ppm based on the amount of starch added;

[0082] S8, mixing raw materials including wet strength agent, aluminum sulfate, cationic polyacrylamide, silica, bleached coniferous pulp and bleached broadleaf pulp in a mass ratio of 3:4:6:15:25:100 to obtain pulp; placing the pulp on a screen to obtain wet paper sheets; pressing and drying the wet paper sheets to obtain base paper;

[0083] S9. Prepare a sizing agent by mixing raw materials including kaolin, calcium carbonate, starch, styrene acrylate copolymer and water in a mass ratio of kaolin: calcium carbonate: starch: styrene acrylate copolymer: water = 5:10:15:100:300; sizing the base paper with the sizing agent, drying and calendering to obtain a paper-based facing material; wherein, based on the total amount of the styrene acrylate copolymer as 100 parts by mass, the styrene acrylate copolymer includes: acrylic acid, 2 parts by mass; ethyl acetate, 6 parts by mass; butyl acetate, 8 parts by mass; toluene, 10 parts by mass; methyl acrylate, 12 parts by mass; butyl acrylate, 30 parts by mass; and styrene, 32 parts by mass.

Claims

1. A method for preparing a paper-based facing material modified by a styrene acrylate copolymer, characterized in that: The preparation method comprises: S100, preparing base paper using raw materials including a wet strength agent, aluminum sulfate, cationic polyacrylamide, silica particles, bleached coniferous wood pulp, bleached hardwood wood pulp and water; S200, mixing raw materials including kaolin, calcium carbonate, starch, styrene acrylate copolymer and water to prepare a sizing agent; S300, applying sizing agent to base paper, drying and calendering to obtain the paper-based facing material.

2. The preparation method according to claim 1, characterized in that: The styrene acrylate copolymer comprises: acrylic acid, ethyl acetate, butyl acetate, toluene, methyl acrylate, butyl acrylate and styrene.

3. The preparation method according to claim 1, characterized in that: Taking the total amount of the styrene acrylate copolymer as 100 parts by mass, the styrene acrylate copolymer comprises: Acrylic acid, 1 to 2 parts by mass; Ethyl acetate, 6 to 8 parts by mass; Butyl acetate, 8 to 10 parts by mass; Toluene, 10 to 12 parts by mass; Methyl acrylate, 12 to 14 parts by mass; Butyl acrylate, 28 to 30 parts by mass; Styrene: 30 to 32 parts by mass.

4. The preparation method according to claim 1, characterized in that: S100 specifically includes: S110, mixing and pulping raw materials including the wet strength agent, the aluminum sulfate, the cationic polyacrylamide, the silicon dioxide, the bleached coniferous wood pulp and the bleached hardwood wood pulp to obtain pulp; S120, placing the slurry on a screen to make paper sheets to obtain wet paper sheets; S130, pressing and drying the wet paper sheets to obtain the base paper.

5. The preparation method according to claim 4, characterized in that: Calculated by mass ratio, wet strength agent: aluminum sulfate: cationic polyacrylamide: silicon dioxide: bleached coniferous pulp: bleached hardwood pulp = (3-4): (4-5): (5-6): (12-16): (15-25):

100.

6. The preparation method according to claim 1, characterized in that: S200 specifically includes: S210, mixing the kaolin, the calcium carbonate, the starch and the styrene acrylate copolymer in water to prepare a slurry; S220, shearing and mixing the slurry evenly to prepare the sizing agent.

7. The preparation method according to claim 6, characterized in that: In terms of mass ratio, kaolin: calcium carbonate: starch: styrene acrylate copolymer: water = (5-10): (10-15): (15-20): (100-120): (250-350).

8. The preparation method according to any one of claims 1 to 7, characterized in that The starch is enzymatically hydrolyzed starch that has been enzymatically hydrolyzed by using α-amylase.

9. The preparation method according to any one of claims 1 to 7, characterized in that: The calcium carbonate contains titanium dioxide.

10. A styrene acrylate copolymer modified paper-based facing material, characterized in that: The styrene acrylate copolymer-modified paper-based facing material is obtained by the preparation method according to any one of claims 1 to 9.