Photocatalytic degradation polyethylene-coated paper and preparation method thereof

Abstract

The application relates to the technical field of laminated paper processing, and particularly discloses a polyethylene laminated paper capable of photocatalytic degradation and a preparation method thereof. The polyethylene laminated paper capable of photocatalytic degradation comprises the following raw materials in parts by weight: 70-80 parts of polyethylene, 0.5-0.8 parts of erucic acid amide, 1-3 parts of photo-oxygen degradation master batch, 0.2-2 parts of silicone powder, 0.1-0.5 parts of photosensitizer and 1-3 parts of nano inorganic filler, wherein the photo-oxygen degradation master batch is obtained by loading titanium dioxide on Mxene material; the preparation method comprises the following steps: uniformly mixing the polyethylene, the photo-oxygen degradation master batch, the silicone powder and the erucic acid amide, heating and melting, sequentially adding the photosensitizer and the nano inorganic filler, and continuously uniformly dispersing and mixing; and spraying the obtained laminated material on the base paper, drying and obtaining the polyethylene laminated paper capable of photocatalytic degradation. The composition disclosed by the application can be used in the packaging of food, medicine, agriculture and other industries, and has the advantages of rapid degradation, no pollution to the environment and good tensile strength.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of laminated paper processing, in particular to a polyethylene laminated paper with photocatalytic degradation BACKGROUND

[0002] Laminated paper is a composite material in which plastic particles are applied to the outer surface of paper by a casting machine. Polyethylene laminated paper is a commonly used packaging material that is widely used in the food, pharmaceutical, and agricultural industries due to its excellent physical properties and chemical stability. However, while polyethylene laminated paper brings convenience, it also poses a serious environmental pollution problem. Due to the stable chemical structure of polyethylene, it is difficult for microorganisms to decompose it in the natural environment. Therefore, traditional polyethylene laminated paper often persists in the environment for a long time after being discarded, causing environmental problems such as soil pollution and water pollution.

[0003] In order to solve the degradation problem of polyethylene laminated paper, researchers have conducted a large amount of research. Currently, some methods have been attempted to improve the degradability of polyethylene laminated paper, such as adding biodegradable agents and using degradable polymers instead of polyethylene. However, these methods still have certain limitations in practical application. For example, adding biodegradable agents may reduce the physical properties of polyethylene laminated paper, affecting its use effect; and using degradable polymers instead of polyethylene may increase production costs, limiting its widespread application.

[0004] Therefore, it is particularly important to develop a new material that maintains the excellent physical properties of polyethylene laminated paper while rapidly degrading in the natural environment. SUMMARY

[0005] In order to maintain the good physical properties of polyethylene while achieving the degradation of polyethylene laminated paper, the application provides a polyethylene laminated paper with photocatalytic degradation and a preparation method thereof.

[0006] In a first aspect, the application provides a polyethylene laminated paper with photocatalytic degradation, which adopts the following technical solution:

[0007] A polyethylene laminated paper with photocatalytic degradation comprises the following raw materials by weight:

[0008] 70-80 parts of polyethylene, 0.5-0.8 parts of erucic acid amide, 1-3 parts of photo-oxygen degradation master batch, 0.2-2 parts of silicone powder, 0.1-0.5 parts of photosensitizer, and 1-3 parts of nano inorganic filler, wherein the photo-oxygen degradation master batch is obtained by loading titanium dioxide on Mxene material.

[0009] By adopting the above technical solutions, the addition of erucic acid amide significantly improves the physical and mechanical properties of the coated paper. By reducing friction and adhesion between polyethylene molecular chains, it effectively enhances the smoothness and slip properties of the coated paper, making it smoother to use and improving its overall flexibility. Furthermore, erucic acid amide also enhances the tensile strength and elongation at break of the coated paper, significantly improving its superior mechanical properties under external forces. Silicone powder, with its good compatibility and miscibility, can form a homogeneous mixture with the polyethylene molecular chains, thereby reducing the melt viscosity of polyethylene during processing, making it easier to flow, effectively preventing defects such as bubbles and small particles on the polyethylene surface, and improving the mechanical properties of the coated paper.

[0010] Nano-inorganic fillers have a large specific surface area and high surface activity, which can form strong interaction forces with polyethylene molecular chains, thereby improving the strength of coated paper and maintaining its structural stability and integrity when coated paper is subjected to large external forces.

[0011] The addition of photocatalytic degradation masterbatch endows the coated paper with excellent photocatalytic degradation performance. Titanium dioxide is a commonly used photocatalyst that can catalyze the degradation reaction of polyethylene under light conditions, thereby achieving rapid degradation of the coated paper. By attaching titanium dioxide to Mxene material, not only is the degradation rate improved, but the compatibility and dispersion uniformity with other raw materials are also enhanced. At the same time, the overall mechanical properties of the coated paper are improved, so that the coated paper maintains good performance while possessing environmental protection characteristics.

[0012] Optionally, the preparation of the photo-oxidative degradation masterbatch includes the following steps:

[0013] (1) Dissolve tetrabutyl titanate in a mixed solution of ethanol and deionized water, add aryltriazole and sodium dodecyl sulfate, and add potassium permanganate solution dropwise at 150-200℃ while stirring and react for 8-10 hours.

[0014] (2) When the temperature drops to 35-40℃, add Mxene material and sonicate under sealed conditions until the dispersion is uniform. After reacting for 2-3 hours, wash and dry to obtain photo-oxidative degradation masterbatch.

[0015] By adopting the above technical solution, aryltriazole molecules have the ability to absorb radiation energy and generate electronic transitions. This property can enhance the material's light absorption and utilization efficiency. By combining aryltriazole molecules with silicon dioxide, the photosensitivity of titanium dioxide can be further improved, making the photocatalytic degradation process more efficient.

[0016] The prepared photo-oxidative degradation masterbatch is added to polyethylene. By absorbing light, the attached silica is excited to photocatalyze the degradation of polyethylene. At the same time, MXene is unstable under environmental conditions and is easily degraded by oxidation, which further accelerates the degradation efficiency of polyethylene. Moreover, the MXene material has a multi-layer sheet-like morphology. The attachment of titanium dioxide on it can improve the compatibility between titanium dioxide and raw materials and make it easier to mix. This makes the raw materials of polyethylene film paper evenly dispersed, thereby improving the photocatalytic performance of the catalyst.

[0017] Optionally, the photo-oxidative degradation masterbatch includes 4-6 parts tetrabutyl titanate, 1-2 parts sodium dodecyl sulfate, 16-20 parts ethanol, 2-4 parts water, 1-3 parts potassium permanganate solution, 0.03-0.05 parts aryltriazole, and 8-10 parts Mxene material.

[0018] Optionally, the nano-inorganic filler is any one of nano-montmorillonite, talc, and mica.

[0019] Optionally, the nano-inorganic filler is obtained through surface activation modification, specifically including the following steps:

[0020] The nano-inorganic filler was dispersed in water and then an appropriate amount of titanate coupling agent was added and ultrasonically stirred. The reaction was carried out at room temperature for 1-2 hours. After the reaction was completed, the nano-inorganic filler was dried to obtain the modified nano-inorganic filler.

[0021] By adopting the above technical solution, nano-inorganic fillers can be uniformly dispersed in polyethylene matrix, reducing the melt viscosity of the material. This not only improves the melt flowability and processing performance, but also the unique size effect of nanomaterials can further enhance the tensile strength and elongation at break of coated paper.

[0022] Optionally, the photosensitizer is ferric dibutyldithiocarbamate.

[0023] By employing the above technical solution and combining it with photocatalytic degradation masterbatch, ferric dibutyldithiocarbamate can further enhance the photocatalytic degradation effect. Titanium dioxide, as a photocatalyst, can generate active species such as hydroxyl radicals under light irradiation. These, along with the free radicals generated by ferric dibutyldithiocarbamate, act on the polyethylene molecular chain, accelerating its degradation process.

[0024] Optionally, 0.3-0.5 parts of phthalocyanine ketone are also added to the raw materials.

[0025] By employing the above technical solution, phthalocyanine ketone can absorb light energy and convert it into chemical energy, thereby initiating or accelerating the photocatalytic degradation process of polyethylene molecules. Its improved photosensitivity helps enhance the photodegradation efficiency of the coated paper, enabling polyethylene to decompose into smaller molecules more quickly under light conditions, thus improving degradation efficiency.

[0026] Secondly, this application provides a method for preparing photocatalytically degradable polyethylene coated paper, employing the following technical solution:

[0027] A method for preparing photocatalytically degradable polyethylene coated paper includes the following steps:

[0028] (1) Mix polyethylene, photo-oxidative degradation masterbatch, silicone powder and erucamide evenly;

[0029] (2) Heat and melt the mixture, and add photosensitizer and nano-inorganic filler, and continue to disperse and mix.

[0030] (3) The obtained coating material is sprayed onto the base paper and dried to obtain photocatalytically degraded polyethylene coated paper.

[0031] In summary, this application has the following beneficial effects:

[0032] 1. Because this application introduces photocatalytic degradation masterbatch obtained by loading titanium dioxide with Mxene material, it significantly improves the photocatalytic degradation performance of coated paper and enhances the dispersion uniformity of titanium dioxide in polyethylene base material, so that coated paper can decompose into small molecules more quickly while maintaining good mechanical properties, thereby improving degradation efficiency.

[0033] 2. In this application, Mxene material is preferably used as a catalyst for silica. On the one hand, it is easily oxidized in air and humid environments, which accelerates the degradation process. On the other hand, it has good mechanical properties, which further improves the tensile strength and breaking strength of the coated paper.

[0034] 3. The surface-activated modified nano-inorganic filler in this application can be uniformly dispersed in the polyethylene matrix, reducing the melt viscosity and improving melt flowability, thereby achieving better processing performance. Simultaneously, the Mxene material exhibits a multi-layered sheet-like morphology, making it easier for titanium dioxide to adhere to it, improving the compatibility between titanium dioxide and the raw materials, and facilitating mixing. These measures work together to ensure uniform dispersion of the raw materials in the coated paper, improve the photocatalytic performance of the catalyst, and further enhance the overall performance of the coated paper. Detailed Implementation

[0035] The present application will be further described in detail below with reference to the embodiments.

[0036] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0037] 1,2,3-Benzotriazole was purchased from Shandong Longhui Chemical Co., Ltd., CAS No. 95-14-7; single-layer Nb4C3Tx MXene powder was purchased from Xinxi Technology Co., Ltd.; polyethylene was purchased from Shouguang Hongchuang Environmental Protection Technology Co., Ltd., model CPE135C.

[0038] Preparation examples of raw materials and / or intermediates

[0039] Preparation Example 1

[0040] A photo-oxidative degradation masterbatch is prepared by the following steps:

[0041] (1) Dissolve 4 kg of tetrabutyl titanate in a mixed solution of 18 kg of ethanol and 4 kg of deionized water, add 0.04 kg of 1,2,3-benzotriazole and 1 kg of sodium dodecyl sulfate, and add 1 kg of potassium permanganate solution with a mass concentration of 0.02% dropwise while stirring. React at 180°C for 9 h.

[0042] (2) The reaction temperature was lowered to 40℃, 9kg of Mxene material was added and sealed and ultrasonically dispersed until uniform. After reacting for 2 hours, the mixture was repeatedly washed with ethanol and deionized water and then dried in a vacuum drying oven at 60℃ to obtain photo-oxidative degradation masterbatch.

[0043] Preparation Example 2

[0044] A photo-oxidative degradation masterbatch is prepared by the following steps:

[0045] (1) Dissolve 5 kg of tetrabutyl titanate in a mixed solution of 16 kg of ethanol and 3 kg of deionized water, add 0.03 kg of 1,2,3-benzotriazole and 2 kg of sodium dodecyl sulfate, and add 2 kg of potassium permanganate solution with a mass concentration of 0.02% dropwise while stirring. React at 150°C for 8 h.

[0046] (2) The reaction temperature was lowered to 35℃, 8kg of Mxene material was added and sealed and ultrasonically dispersed until uniform. After reacting for 2 hours, the mixture was repeatedly washed with ethanol and deionized water and then dried in a vacuum drying oven at 60℃ to obtain photo-oxidative degradation masterbatch.

[0047] Preparation Example 3

[0048] A photo-oxidative degradation masterbatch is prepared by the following steps:

[0049] (1) Dissolve 6 kg of tetrabutyl titanate in a mixed solution of 20 kg of ethanol and 2 kg of deionized water, add 0.05 kg of 1,2,3-benzotriazole and 1.5 kg of sodium dodecyl sulfate, and add 3 kg of potassium permanganate solution with a mass concentration of 0.02% dropwise while stirring. React at 180°C for 9 h.

[0050] (2) The reaction temperature was lowered to 38℃, 10kg of Mxene material was added and ultrasonically sealed until it was evenly dispersed. After reacting for 2 hours, the mixture was repeatedly washed with ethanol and deionized water and then dried in a vacuum drying oven at 60℃ to obtain photo-oxidative degradation masterbatch.

[0051] Preparation Example 4

[0052] A photo-oxidative degradation masterbatch, differing from Preparation Example 1 in that no Mxene material was added in this preparation example, specifically including the following steps:

[0053] (1) Dissolve 4 kg of tetrabutyl titanate in a mixed solution of 18 kg of ethanol and 4 kg of deionized water, add 0.04 kg of 1,2,3-benzotriazole and 1 kg of sodium dodecyl sulfate, and add 1 kg of potassium permanganate solution with a mass concentration of 0.02% dropwise while stirring. React at 180°C for 9 h.

[0054] (2) The reaction temperature was reduced to 40℃, and the mixture was sealed and ultrasonically dispersed evenly. After being placed for 2 hours, it was repeatedly washed with ethanol and deionized water and then dried in a vacuum drying oven at 60℃ to obtain photo-oxidative degradation masterbatch.

[0055] Preparation Example 5

[0056] A photo-oxidative degradation masterbatch, which differs from Preparation Example 1 in that aryltriazole was not used to pre-sensitize silica in this preparation example, and specifically includes the following steps:

[0057] (1) Dissolve 4 kg of tetrabutyl titanate in a mixed solution of 18 kg of ethanol and 4 kg of deionized water, add 1 kg of sodium dodecyl sulfate, and add 1 kg of potassium permanganate solution with a mass concentration of 0.02% dropwise while stirring. React at 180°C for 9 h.

[0058] (2) The reaction temperature was lowered to 40℃, 9kg of Mxene material was added and sealed and ultrasonically dispersed until uniform. After reacting for 2 hours, the mixture was repeatedly washed with ethanol and deionized water and then dried in a vacuum drying oven at 60℃ to obtain photo-oxidative degradation masterbatch.

[0059] Preparation Example 6

[0060] A modified nano-inorganic filler is prepared by the following steps:

[0061] 3 kg of nano-montmorillonite was dispersed in 5 kg of water, and then 1.5 kg of isopropyltris(isostearoyl)titanate was added and ultrasonically stirred. The mixture was reacted at room temperature for 2 h. After the reaction was completed, the modified nano-inorganic filler was obtained by drying.

[0062] Example

[0063] Example 1

[0064] A photocatalytically degradable polyethylene coated paper, prepared by the following steps:

[0065] (1) Mix 75 kg of polyethylene, 2 kg of photo-oxidative degradation masterbatch prepared in Example 1, 1.1 kg of silicone powder, and 0.65 kg of erucamide evenly;

[0066] (2) Heat to 180℃ to melt the mixture, and add 0.25kg of ferric dibutyldithiocarbamate (photosensitizer) and 3kg of nano montmorillonite (nano inorganic filler), and continue to disperse and mix.

[0067] (3) The obtained coating material is added to the hopper of the coating machine, and the base paper is loaded into the coating machine. The coating material is sprayed onto the base paper and then cooled and dried to obtain photocatalytically degraded polyethylene coated paper.

[0068] Example 2

[0069] A photocatalytically degradable polyethylene coated paper, prepared by the following steps:

[0070] (1) Mix 70 kg of polyethylene, 3 kg of photo-oxidative degradation masterbatch prepared in Example 1, 0.2 kg of silicone powder, and 0.8 kg of erucamide evenly;

[0071] (2) Heat to 180°C to melt the mixture, and add 0.1 kg of ferric dibutyldithiocarbamate (photosensitizer) and 1 kg of nano talc powder (nano inorganic filler), and continue to disperse and mix evenly;

[0072] (3) The obtained coating material is added to the hopper of the coating machine, and the base paper is loaded into the coating machine. The coating material is sprayed onto the base paper and then cooled and dried to obtain photocatalytically degraded polyethylene coated paper.

[0073] Example 3

[0074] A photocatalytically degradable polyethylene coated paper, prepared by the following steps:

[0075] (1) Mix 80 kg of polyethylene, 1 kg of photo-oxidative degradation masterbatch prepared in Example 1, 2 kg of silicone powder, and 0.5 kg of erucamide evenly;

[0076] (2) Heat to 180°C to melt the mixture, and add 0.5 kg of ferric dibutyldithiocarbamate (photosensitizer) and 2 kg of nano mica (nano inorganic filler), and continue to disperse and mix.

[0077] (3) The obtained coating material is added to the hopper of the coating machine, and the base paper is loaded into the coating machine. The coating material is sprayed onto the base paper and then cooled and dried to obtain photocatalytically degraded polyethylene coated paper.

[0078] Example 4

[0079] A photocatalytically degradable polyethylene coated paper, which differs from Example 1 in that the photocatalytic degradation masterbatch used in this example was prepared in Example 2.

[0080] Example 5

[0081] A photocatalytically degradable polyethylene coated paper, which differs from Example 1 in that the photocatalytic degradation masterbatch used in this example is the one prepared in Preparation Example 3.

[0082] Example 6

[0083] A photocatalytically degradable polyethylene coated paper, which differs from Example 1 in that the photocatalytic degradation masterbatch used in this example was prepared in Preparation Example 4.

[0084] Example 7

[0085] A photocatalytically degradable polyethylene coated paper, which differs from Example 1 in that the photocatalytic degradation masterbatch used in this example was prepared in Preparation Example 5.

[0086] Example 8

[0087] A photocatalytically degradable polyethylene coated paper, which differs from Example 1 in that the nano-montmorillonite used in this example is obtained by modification of Preparation Example 6.

[0088] Comparative Example

[0089] Comparative Example 1

[0090] A photocatalytically degradable polyethylene coated paper, which differs from Example 1 in that erucamide is not added in this example.

[0091] Comparative Example 2

[0092] A photocatalytically degradable polyethylene coated paper, which differs from Example 1 in that silicone powder is not added in this example.

[0093] Performance testing

[0094] Degradation performance: After irradiation with ultraviolet light for 720 hours at ambient temperature, the molecular weight before and after irradiation was analyzed by light scattering method, and the degradation rate of the coated paper was calculated.

[0095] Tensile strength: According to GB / T1040.3-2006 "Films, Determination of Tensile Properties";

[0096] The elongation at break was tested according to GB / T 1040-2018. The test conditions were 0℃, test speed 100mm / min, clamping length: 100mm, tensile force 150N.

[0097] Table 1 Test Results

[0098] Degradation rate / % Tensile strength / MPa Elongation at break / % Example 1 90.23 45.67 180.45 Example 2 89.76 44.98 179.9 Example 3 90.34 45.23 180.12 Example 4 89.56 44.72 179.34 Example 5 90.01 45.39 180.28 Example 6 82.43 38.09 168.87 Example 7 85.65 41.32 171.67 Example 8 93.12 48.9 186.32 Comparative Example 1 84.34 39.76 174.43 Comparative Example 2 85.67 40.45 176.76

[0099] Combining Examples 1-3 and Comparative Example 1 with Table 1, it can be seen that the experimental data of Examples 1-3 are better than those of Comparative Example 1, indicating that the addition of erucamide can reduce the friction and adhesion between polyethylene molecular chains and greatly improve the tensile strength and elongation at break of the coated paper.

[0100] Combining Examples 1-3 and Comparative Example 2 with Table 1, it can be seen that the experimental data of Examples 1-3 are better than those of Comparative Example 2. This indicates that the addition of silicone powder can form a uniform mixture with polyethylene molecular chains, improve the processing performance of coated paper raw materials, reduce defects in the preparation process, and improve the tensile strength and elongation at break of coated paper.

[0101] Based on Examples 1-6 and Table 1, it can be seen that the experimental data of Examples 1-5 are better than those of Example 6. This indicates that, on the one hand, the addition of Mxene material can improve the tensile strength of the coated paper with its own good mechanical properties, and on the other hand, it can improve the degradation efficiency of the coated paper, with a high degradation rate under the same light exposure time.

[0102] Combining Examples 1 and 7 with Table 1, it can be seen that the experimental data of Example 1 are better than those of Example 7, indicating that pre-sensitization of titanium dioxide with aryltriazole is beneficial to improving the catalytic degradation effect of photo-oxidative degradation masterbatch and further accelerating the degradation efficiency of polyethylene.

[0103] Combining Examples 1 and 8 with Table 1, it can be seen that the experimental data of Example 8 are better than those of Example 1, indicating that further dispersion of the nano-inorganic filler is beneficial to improving its dispersion uniformity in polyethylene, thereby further improving the mechanical properties of the coated paper.

[0104] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A photocatalytically degradable polyethylene coated paper, characterized in that, Including the following parts by weight of raw materials: The composition includes 70-80 parts polyethylene, 0.5-0.8 parts erucamide, 1-3 parts photo-oxidative degradation masterbatch, 0.2-2 parts silicone powder, 0.1-0.5 parts photosensitizer, and 1-3 parts nano-inorganic filler. The photo-oxidative degradation masterbatch is obtained by loading titanium dioxide onto Mxene material. The preparation of the photo-oxidative degradation masterbatch includes the following steps: (1) Dissolve tetrabutyl titanate in a mixed solution of ethanol and deionized water, add aryltriazole and sodium dodecyl sulfate, and add potassium permanganate solution dropwise at 150-200℃ while stirring and react for 8-10 hours. (2) When the temperature drops to 35-40℃, add Mxene material and sonicate under sealed conditions until it is evenly dispersed. After reacting for 2-3 hours, wash and dry to obtain photo-oxidative degradation masterbatch. The photo-oxidative degradation masterbatch comprises 4-6 parts tetrabutyl titanate, 1-2 parts sodium dodecyl sulfate, 16-20 parts ethanol, 2-4 parts water, 1-3 parts potassium permanganate solution, 0.03-0.05 parts aryltriazole, and 8-10 parts Mxene material.

2. The photocatalytically degradable polyethylene coated paper according to claim 1, characterized in that: The nano-inorganic filler is any one of nano-montmorillonite, talc, and mica.

3. The photocatalytically degradable polyethylene coated paper according to claim 2, characterized in that, The nano-inorganic filler is obtained through surface activation modification, specifically including the following steps: The nano-inorganic filler was dispersed in water and then an appropriate amount of titanate coupling agent was added and ultrasonically stirred. The reaction was carried out at room temperature for 1-2 hours. After the reaction was completed, the nano-inorganic filler was dried to obtain the modified nano-inorganic filler.

4. The photocatalytically degradable polyethylene coated paper according to claim 1, characterized in that: The photosensitizer is ferric dibutyldithiocarbamate.

5. The photocatalytically degradable polyethylene coated paper according to claim 1, characterized in that: The raw materials also contain 0.3-0.5 parts of phthalocyanine ketone.

6. A method for preparing photocatalytically degradable polyethylene coated paper according to any one of claims 1-4, characterized in that, Includes the following steps: (1) Mix polyethylene, photodegradation masterbatch, silicone powder and erucamide evenly to obtain a mixture; (2) Heat and melt the mixture, and add photosensitizer and nano-inorganic filler, and continue to disperse and mix evenly; (3) The obtained coating material is sprayed onto the base paper and dried to obtain photocatalytically degraded polyethylene coated paper.