Packaging paper with hydrophobic, antibacterial and writing functions and preparation method thereof

Abstract

The invention discloses packaging paper with hydrophobic, antibacterial and writing functions and a preparation method thereof. The preparation method comprises the following steps: S1, mixing a monomer, an initiator, cellulose pulp and water, and uniformly stirring to obtain a mixed solution; s2, heating the mixed solution to carry out copolymerization reaction, and cooling to room temperature after the reaction is finished to obtain a copolymerization solution; s3, dopamine hydrochloride and a Tris-HCl buffer solution are added, stirring is carried out under the room temperature condition, and cellulose pulp deposited with polydopamine and a copolymer is obtained; s4, performing suction filtration to obtain formed cellulose paper; and S5, drying the cellulose paper, soaking the cellulose paper in water, soaking the cellulose paper in an aqueous solution containing 1-octylsulfonic acid ions and silver ions, washing the cellulose paper with water, drying the cellulose paper, and performing ultraviolet light reduction to obtain the packaging paper with hydrophobic, antibacterial and writing functions. According to the invention, the packaging paper with hydrophobic, antibacterial and writing functions can be prepared without an organic solvent and a fluorine-containing reagent.

Description

Technical Field

[0001] The invention relates to the technical field of packaging paper, and in particular to a packaging paper with hydrophobic, antibacterial and writing functions and a preparation method thereof. Background Art

[0002] Wrapping paper plays an important role in modern society, whether in the business field or in daily life, it plays a role in protecting, conveying information and enhancing the value of products. Wrapping paper made of cellulose has high strength and wear resistance. In addition, its unique texture and appearance perception can enhance the value and attractiveness of the product. Therefore, it is often used in the packaging of books, documents, and artworks. However, most of the current wrapping paper is made of unmodified cellulose, which contains a large number of hydroxyl groups on its surface and has high water absorption, which often reduces its original strength and wear resistance, especially the mildew caused by water absorption, which greatly limits its use in the packaging field.

[0003] The hydrophobic cellulose paper currently sold on the market is mostly made of polyolefin polymers or inorganic nanomaterials and paraffin, etc., through coating, dipping, spraying and other processes. The prepared hydrophobic coating is thick, easy to break, and has poor effect; in addition, the preparation process often requires a large amount of organic solvents, which is easy to cause environmental pollution; at the same time, the hydrophobic agent and its coating process currently available on the market cannot meet the requirements of cellulose paper packaging products with hydrophobic, antibacterial and writing properties. Summary of the invention

[0004] In view of the above problems, the present invention aims to provide a packaging paper having hydrophobic, antibacterial and writing functions and a preparation method thereof.

[0005] The technical solution of the present invention is as follows:

[0006] On the one hand, a method for preparing a packaging paper having hydrophobic, antibacterial and writing functions is provided, comprising the following steps:

[0007] S1: Mixing monomers, initiators, cellulose pulp and water, and stirring to obtain a mixed solution; the monomers include a monomer 1 containing a double bond and an amine group, and a monomer 2 containing a double bond and an exchangeable bromide ion and an ionic liquid with 4 methylene branches;

[0008] S2: heating the mixed solution to perform copolymerization reaction, and cooling to room temperature after the reaction to obtain a copolymerization solution;

[0009] S3: adding dopamine hydrochloride and Tris-HCl buffer to the copolymerization solution, stirring at room temperature to obtain cellulose pulp with polydopamine and copolymer deposited thereon;

[0010] S4: filtering the cellulose pulp on which the polydopamine and the copolymer are deposited to obtain formed cellulose paper;

[0011] S5: After drying the cellulose paper, immerse it in water to remove the unbonded polydopamine and copolymer, then immerse it in an aqueous solution containing 1-octyl sulfonic acid ions and silver ions, and finally wash it with water, dry it, and reduce it with ultraviolet light to obtain the packaging paper with hydrophobic, antibacterial and writing functions.

[0012] Preferably, in step S1, the monomer one is 2-aminoethyl methacrylate hydrochloride and / or 2-aminoethyl ethylacrylate hydrochloride, and the monomer two is any one or more of 1-vinyl-3-butylimidazolium bromide, 1-vinyl-3-propylimidazolium bromide, and 1-vinyl-3-ethylimidazolium bromide.

[0013] Preferably, in step S1, the initiator is azobisisobutylamidine hydrochloride or ammonium persulfate.

[0014] Preferably, in step S1, the mass ratio of the monomer one to the monomer two is 1:9-4:6, the amount of the initiator is 1-3% of the total mass of the monomers, and the concentration of the cellulose pulp is 1-4 mg / mL; in step S3, the amount of dopamine hydrochloride is 1-4 mg / mL, and the Tris-HCl buffer is used to adjust the pH value of the solution to 8-9; in step S5, in the aqueous solution containing 1-octane sulfonate ions and silver ions, the concentration of 1-octane sulfonate ions is 0.1-0.5 M, and the concentration of silver ions is 5-20 mg / mL.

[0015] Preferably, in step S2, before heating the mixed solution, the step of deoxygenating and sealing the mixed solution is also included.

[0016] Preferably, deoxygenation is performed by bubbling under inert gas conditions for 10-60 min.

[0017] Preferably, in step S2, the copolymerization reaction is carried out at a temperature of 65-85° C. and a time of 12-24 h.

[0018] Preferably, in step S3, the stirring time is 12-24 hours.

[0019] Preferably, in step S5, the immersion time in the aqueous solution containing 1-octane sulfonic acid ions and silver ions is 0.5-8 hours.

[0020] On the other hand, a wrapping paper having hydrophobic, antibacterial and writing functions is provided, which is prepared by any of the above-mentioned methods for preparing wrapping paper having hydrophobic, antibacterial and writing functions.

[0021] The beneficial effects of the present invention are:

[0022] 1. The preparation process of the present invention does not require organic solvents and fluorine-containing reagents, and the operation is simple, convenient for mass production, and environmentally friendly.

[0023] 2. The paper prepared by the present invention has hydrophobic properties. Some of the paper has a water contact angle greater than 150° and can achieve super hydrophobicity. When used as packaging paper, it will not get wet and can effectively protect the items to be packaged. At the same time, the antibacterial efficiency against Escherichia coli, Staphylococcus aureus and mold is as high as 99%, and it will not be contaminated by mold in the air.

[0024] 3. The paper prepared by the present invention has beautiful color and is convenient for writing. When used for packaging books, documents, and artworks, it will not affect the appearance and value of the original items. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0026] Figure 1 The figure is a schematic flow chart of a method for preparing a packaging paper having hydrophobic, antibacterial and writing functions according to the present invention;

[0027] Figure 2 Schematic diagram of the test results of the hydrophobicity of the packaging paper prepared in various embodiments of the present invention;

[0028] Figure 3 Schematic diagram of the antibacterial performance test results of the packaging paper prepared in various embodiments of the present invention;

[0029] Figure 4 Schematic diagram of writing function test results of packaging paper prepared according to various embodiments of the present invention. DETAILED DESCRIPTION

[0030] The present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, in the absence of conflict, the embodiments in this application and the technical features in the embodiments can be combined with each other. It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as those generally understood by those of ordinary skill in the art to which this application belongs. The words "including" or "comprising" and the like used in the disclosure of the present invention mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0031] On the one hand, if Figure 1 As shown, the present invention provides a method for preparing a packaging paper having hydrophobic, antibacterial and writing functions, comprising the following steps:

[0032] S1: Mix monomers, initiators, cellulose pulp and water, and stir them evenly to obtain a mixed solution; the monomers include monomer 1 containing a double bond and an amine group and monomer 2 of an ionic liquid containing a double bond and exchangeable bromide ions and having 4 methylene branches.

[0033] In a specific embodiment, the monomer one is 2-aminoethyl methacrylate hydrochloride (AEMA) and / or 2-aminoethyl ethylacrylate hydrochloride, the monomer two is any one or more of 1-vinyl-3-butylimidazolium bromide (BVIM), 1-vinyl-3-propylimidazolium bromide, and 1-vinyl-3-ethylimidazolium bromide, and the initiator is azobisisobutyramidine hydrochloride (AIBA) or ammonium persulfate.

[0034] It should be noted that the initiators in the above embodiments are only preferred initiators of the present invention, and other initiators that can initiate copolymerization of monomers may also be applicable to the present invention.

[0035] S2: heating the mixed solution to perform copolymerization reaction, and cooling to room temperature after the reaction is completed to obtain a copolymerization solution.

[0036] In a specific embodiment, before heating the mixed solution, the mixed solution is further deoxygenated and sealed. Optionally, deoxygenation is performed by bubbling under inert gas conditions for 10-60 minutes.

[0037] In a specific embodiment, the copolymerization reaction is carried out at a temperature of 65-85° C. and a time of 12-24 hours.

[0038] S3: adding dopamine hydrochloride and Tris-HCl buffer to the copolymerization solution, stirring at room temperature, and obtaining cellulose pulp with polydopamine and copolymer deposited thereon.

[0039] In a specific embodiment, the stirring time in this step is 12-24 hours.

[0040] S4: filtering the cellulose pulp on which the polydopamine and the copolymer are deposited to obtain formed cellulose paper.

[0041] In a specific embodiment, during the suction filtration, the cellulose pulp with the polydopamine and copolymer deposited thereon is poured into a filtration device, wherein a medium-speed filter paper and a 200-400 mesh stainless steel wire are sandwiched in the middle of the filtration device. The filtration is carried out under a pressure greater than 0.08 MPa for 5-10 minutes, and the formed paper is peeled off from the stainless steel wire to obtain the modified cellulose paper.

[0042] S5: After drying the cellulose paper, immerse it in water to remove the unbonded polydopamine and copolymer, then immerse it in an aqueous solution containing 1-octyl sulfonic acid ions and silver ions, and finally wash it with water, dry it, and reduce it with ultraviolet light to obtain the packaging paper with hydrophobic, antibacterial and writing functions.

[0043] In a specific embodiment, when drying the cellulose paper, the drying is performed at 55-75° C. for 1-4 hours; the soaking time in the aqueous solution containing 1-octane sulfonic acid ions and silver ions is 0.5-8 hours; and the ultraviolet light reduction time is 15 minutes.

[0044] In a specific embodiment, in step S1, the mass ratio of the monomer one to the monomer two is 1:9-4:6, the amount of the initiator is 1-3% of the total mass of the monomers, and the concentration of the cellulose pulp is 1-4 mg / mL; in step S3, the amount of dopamine hydrochloride is 1-4 mg / mL, and the Tris-HCl buffer is used to adjust the pH value of the solution to 8-9; in step S5, in the aqueous solution containing 1-octane sulfonate ions and silver ions, the concentration of 1-octane sulfonate ions is 0.1-0.5 M, and the concentration of silver ions is 5-20 mg / mL.

[0045] The present invention mainly utilizes that dopamine can be coated on the CP surface under mild conditions and form polydopamine on the surface; the polymer between monomer one and monomer two contains an amine group and can react with polydopamine, thereby modifying the CP paper.

[0046] Since monomer 2 contains hydrophilic bromide ions, the hydrophilic bromide ions on the obtained copolymer can be exchanged with hydrophobic 1-octane sulfonic acid ions by simple immersion to achieve hydrophobic effect; combined with the structure of the surface of silver nanoparticles, the super water of the modified CP paper is achieved together.

[0047] In addition, the modified CP paper contains phenolic hydroxyl and amine groups that can bind silver ions and can be reduced to silver nanoparticles under ultraviolet conditions to achieve sustained antibacterial effects; at the same time, the prepared paper contains copolymers that carry partial positive charges, which also contribute to the antibacterial effect.

[0048] On the other hand, the present invention further provides a wrapping paper having hydrophobic, antibacterial and writing functions, which is prepared by any of the above-mentioned methods for preparing wrapping paper having hydrophobic, antibacterial and writing functions.

[0049] Example 1

[0050] A wrapping paper with hydrophobic, antibacterial and writing functions is prepared by the following steps:

[0051] (1) 0.4 g of 2-aminoethyl methacrylate hydrochloride, 1.6 g of 1-vinyl-3-butylimidazolium bromide, 20 mg of azobisisobutyramidine hydrochloride, 0.1 g of cellulose pulp and 45 mL of water were mixed and stirred to obtain a mixed solution;

[0052] (2) bubbling the mixed solution for deoxygenation for 30 min under inert gas conditions, sealing it and placing it in an oil bath, copolymerizing it at 70° C. for 24 h, and cooling it to room temperature after the reaction to obtain a copolymerization solution;

[0053] (3) adding 0.1 g of dopamine hydrochloride and 5 mL of Tris-HCl buffer to the copolymer solution, stirring at room temperature for 24 hours, and obtaining a cellulose pulp having polydopamine and copolymer deposited thereon;

[0054] (4) pouring the cellulose pulp deposited with polydopamine and copolymer into a filtering device, sandwiching a medium-speed filter paper and a 400-mesh stainless steel wire in the middle, and filtering at 0.1 MPa for 5 minutes to obtain a formed cellulose paper;

[0055] (5) The cellulose paper was dried at 60° C. for 2 h, and then immersed in water overnight to remove unbonded polydopamine and copolymer; then immersed in 0.1 M 1-octane sulfonate sodium and 10 mg / mL AgNO3 aqueous solution for 8 h, and finally washed with water, dried at 60° C., and reduced with ultraviolet light for 15 min to obtain the packaging paper with hydrophobic, antibacterial and writing functions, which was recorded as 2CP-2-40@Ag-5.

[0056] Example 2

[0057] Different from Example 1, in step (5) of this example, the silver nitrate was immersed for a total of 4 hours, and the obtained packaging paper with hydrophobic, antibacterial and writing functions was recorded as 2CP-2-40@Ag-4.

[0058] Example 3

[0059] Different from Example 1, in step (5) of this example, the silver nitrate was immersed for a total of 2 hours, and the obtained packaging paper with hydrophobic, antibacterial and writing functions was recorded as 2CP-2-40@Ag-3.

[0060] Example 4

[0061] Different from Example 1, in step (5) of this example, the silver nitrate was immersed for a total of 1 hour, and the obtained packaging paper with hydrophobic, antibacterial and writing functions was recorded as 2CP-2-40@Ag-4.

[0062] Example 5

[0063] Different from Example 1, in step (5) of this example, the silver nitrate was immersed for a total of 0.5 h, and the obtained packaging paper with hydrophobic, antibacterial and writing functions was recorded as 2CP-2-40@Ag-1.

[0064] The hydrophobicity test of the packaging paper prepared in each embodiment is as follows: Figure 2 As shown. Figure 2 (a) It can be seen that the water contact angles of the packaging paper of the present invention are all greater than 140°, showing hydrophobic properties. In addition, except for 2CP-2-40@Ag-1 in Example 5, where the total immersion time of silver nitrate is not long enough, the water contact angles of the other papers are all greater than 150°, achieving super hydrophobic properties. Figure 2 (b) It can be seen that when the paper is rinsed with running water, no moisture will remain on the surface of the paper.

[0065] The antibacterial performance of the packaging paper prepared in each embodiment was tested, and the results are as follows: Figure 3 As shown. Figure 3 (a) It can be seen that when the hydrophobic antibacterial writable paper prepared by the present invention is co-cultured with the E. coli solution for 4 hours, the paper is used to lay the plate, and there is no live bacteria on the surface of the modified paper. Figure 3 (b) It can be seen that the modified paper of the present invention can kill bacteria that are not in contact with the surrounding area through the release of silver ions, which can be confirmed by the inhibition zone experiment. Figure 3 (c) It can be seen that when the modified paper of the present invention is incubated with a solution containing mold, no mold grows on the surface.

[0066] The wrapping paper prepared in each embodiment was used for writing test, and the results are as follows: Figure 4 As shown. Figure 4 It can be seen that compared with unmodified CP paper, the packaging paper prepared by the present invention has good sensory and writing functions.

[0067] In summary, the present invention can prepare packaging paper with hydrophobic, antibacterial and writing functions without the need for organic solvents and fluorine-containing reagents. Compared with the prior art, the present invention has significant progress.

[0068] The above description is only a representative embodiment of the present invention and does not limit the present invention in any form. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, uses the above-disclosed technical contents to make some changes or modifications to the embodiments are equivalent embodiments of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a wrapping paper having hydrophobic, antibacterial and writing functions, characterized in that: The following steps are involved: S1: Mixing monomers, initiators, cellulose pulp and water, and stirring to obtain a mixed solution; the monomers include a monomer 1 containing a double bond and an amine group, and a monomer 2 containing a double bond and an exchangeable bromide ion and an ionic liquid with 4 methylene branches; S2: heating the mixed solution to perform copolymerization reaction, and cooling to room temperature after the reaction to obtain a copolymerization solution; S3: adding dopamine hydrochloride and Tris-HCl buffer to the copolymerization solution, stirring at room temperature to obtain cellulose pulp with polydopamine and copolymer deposited thereon; S4: filtering the cellulose pulp on which the polydopamine and the copolymer are deposited to obtain formed cellulose paper; S5: After drying the cellulose paper, immerse it in water to remove the unbonded polydopamine and copolymer, then immerse it in an aqueous solution containing 1-octyl sulfonic acid ions and silver ions, and finally wash it with water, dry it, and reduce it with ultraviolet light to obtain the packaging paper with hydrophobic, antibacterial and writing functions.

2. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 1, characterized in that: In step S1, the monomer 1 is 2-aminoethyl methacrylate hydrochloride and / or 2-aminoethyl ethylacrylate hydrochloride, and the monomer 2 is any one or more of 1-vinyl-3-butylimidazolium bromide, 1-vinyl-3-propylimidazolium bromide, and 1-vinyl-3-ethylimidazolium bromide.

3. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 1, characterized in that: In step S1, the initiator is azobisisobutylamidine hydrochloride or ammonium persulfate.

4. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 1, characterized in that: In step S1, the mass ratio of the monomer one to the monomer two is 1:9-4:6, the amount of the initiator is 1-3% of the total mass of the monomers, and the concentration of the cellulose pulp is 1-4 mg / mL; in step S3, the amount of dopamine hydrochloride is 1-4 mg / mL, and the Tris-HCl buffer is used to adjust the pH value of the solution to 8-9; in step S5, in the aqueous solution containing 1-octane sulfonic acid ions and silver ions, the concentration of 1-octane sulfonic acid ions is 0.1-0.5M, and the concentration of silver ions is 5-20 mg / mL.

5. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 1, characterized in that: In step S2, before heating the mixed solution, the step of deoxygenating and sealing the mixed solution is also included.

6. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 5, characterized in that: Deoxygenation was performed by bubbling under inert gas conditions for 10-60 min.

7. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 1, characterized in that: In step S2, the copolymerization reaction is carried out at a temperature of 65-85° C. and for a time of 12-24 hours.

8. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 1, characterized in that: In step S3, the stirring time is 12-24 hours.

9. The method for preparing the packaging paper having hydrophobic, antibacterial and writing functions according to claim 1, characterized in that: In step S5, the immersion time in the aqueous solution containing 1-octane sulfonic acid ions and silver ions is 0.5-8 hours.

10. A wrapping paper with hydrophobic, antibacterial and writing functions, characterized in that: The packaging paper is prepared by the method for preparing the packaging paper having hydrophobic, antibacterial and writing functions as described in any one of claims 1 to 9.

Images