Environment-friendly composite hose with aluminized PE as intermediate layer and preparation method thereof

Abstract

The application discloses an environment-friendly composite hose with an aluminized PE as an intermediate layer and a preparation method thereof, and relates to the technical field of layered composite hoses.The composite hose comprises, from inside to outside, an inner layer, an intermediate layer and an outer layer, wherein the outer layer is an anti-aging layer, and the anti-aging layer is composed of the following components in parts by mass: 40-65 parts of water-based acrylic resin, 15-35 parts of color paste, 1-3 parts of dispersing agent, 0.5-2 parts of defoaming agent, 10-25 parts of deionized water and 1-5 parts of anti-ultraviolet aging agent.The degradable polyester material is used as the inner layer, and the regenerated polyester material is used as the outer layer, so that the dependence on petroleum resources and the environmental pollution risk are greatly reduced, the ecological footprint is reduced, and the biological degradation is facilitated while the good barrier property and mechanical property are maintained.

Description

Technical Field

[0001] This invention relates to the field of layered composite hose technology, specifically to an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer and its preparation method. Background Technology

[0002] Currently, with increasing environmental awareness, the requirements for the environmental performance of packaging materials are becoming more and more stringent. Composite flexible tubes, as a common packaging material, are widely used in food, cosmetics, pharmaceuticals, and other fields. However, traditional composite flexible tubes have some environmental problems.

[0003] Traditional composite hoses are mainly composed of various plastic materials, such as polyethylene, polyvinyl chloride, polypropylene, and polyester. The production of these materials consumes large amounts of petroleum resources and is difficult to degrade, causing serious white pollution. Furthermore, the adhesives and inks used in the production of traditional composite hoses also contain harmful substances, such as organic solvents and heavy metals. These substances may migrate into food and other products during packaging, posing potential health hazards.

[0004] To address these issues, researchers have recently begun exploring methods for manufacturing environmentally friendly composite hoses. Among these, an environmentally friendly composite hose with an aluminized polyethylene layer as the intermediate layer presents a promising solution. This type of composite hose maintains good barrier and mechanical properties while reducing environmental pollution.

[0005] Aluminized polyethylene (APE) material possesses excellent barrier and reflective properties, effectively preventing the penetration of substances such as oxygen and water vapor, thus extending the product's shelf life. Simultaneously, the use of APE material reduces the thickness of composite hoses, thereby decreasing the overall amount of composite hose material used, which helps reduce resource consumption and waste generation.

[0006] However, existing composite hoses with an aluminized polyethylene layer as the intermediate layer still have some shortcomings in terms of environmental performance. For example, their outer layer material is usually made of traditional polyester, the production process of which still relies on petroleum resources and is difficult to degrade. In addition, the adhesives and inks used in the production of existing composite hoses have not fully met environmental protection requirements.

[0007] Therefore, developing a new type of environmentally friendly composite hose with an aluminized polyethylene layer as the intermediate layer and its preparation method, and improving environmental performance by replacing traditional auxiliary materials with environmentally friendly auxiliary materials, is of great significance for promoting the packaging industry towards environmental protection. Summary of the Invention

[0008] This invention aims to provide an environmentally friendly composite hose with an aluminized polyethylene layer as the intermediate layer and its preparation method. By employing biodegradable polyester materials, recycled polyester materials, and environmentally friendly auxiliary materials, and further adding a special anti-UV aging agent as a key component, the outer layer of the hose with added biodegradable and environmentally friendly auxiliary materials is protected from degradation caused by UV radiation. This improves the environmental performance of the composite hose while maintaining good barrier and mechanical properties.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is: an environmentally friendly composite hose with aluminized PE as the intermediate layer, comprising, from the inside out: an inner layer of biodegradable polyester material; an intermediate layer of aluminized polyethylene film, wherein the aluminized polyethylene film includes an aluminized layer and a polyethylene layer, with the aluminized layer facing the inner layer; and an outer layer of anti-aging layer.

[0010] The anti-aging layer includes an anti-UV aging agent with the structure shown in Formula 1.

[0011]

[0012] R1 is selected from: methyl, ethyl, tert-butyl, methoxy.

[0013] Furthermore, the anti-aging layer is composed of the following components in parts by weight: 40-65 parts of water-based acrylic resin, 15-35 parts of color paste, 1-3 parts of dispersant, 0.5-2 parts of defoamer, 10-25 parts of deionized water, and 1-5 parts of the above-mentioned anti-UV aging agent.

[0014] Furthermore, the waterborne acrylic resin has a solid content of ≥50% and an acid value of 30-60 mg (KOH / g) pure solids.

[0015] Furthermore, the pigment is selected from any one of the following: Phthalocyanine Green G, Phthalocyanine Blue BGS, Permanent Red F4R, and Titanium Dioxide R-706.

[0016] Furthermore, the color paste contains ≤20ppm of heavy metals (total of lead, cadmium, mercury, and hexavalent chromium), ≤1mg / kg of polycyclic aromatic hydrocarbons (PAHs), and does not contain phthalate plasticizers.

[0017] Furthermore, the dispersant is specifically Nopco 5040 dispersant; the defoamer is specifically sodium dodecyl sulfonate.

[0018] Furthermore, the UV-protective aging agent is selected from any one of the compounds shown in the following structures:

[0019]

[0020]

[0021] Furthermore, the method for preparing the anti-aging layer is as follows: the water-based acrylic resin, color paste, dispersant, defoamer, deionized water and anti-UV aging agent are mixed and stirred evenly to form the anti-aging layer slurry; the anti-aging layer slurry is coated on the surface of the intermediate layer and dried and cured at 60-80℃ to obtain the anti-aging layer.

[0022] Furthermore, the biodegradable polyester material layer is made of polylactic acid.

[0023] Furthermore, the material used for the aluminized polyethylene film layer is an aluminized polyethylene film, with an aluminized layer thickness of 20-40 nm and a polyethylene layer thickness of 10-30 μm.

[0024] This invention also provides a method for preparing the above-mentioned environmentally friendly composite hose with aluminized PE as the intermediate layer, comprising the following steps:

[0025] S1. The anti-aging slurry is applied to the surface of the polyethylene layer and dried and cured at 60-80℃ to obtain a prefabricated composite film;

[0026] S2. Coat the surface of the biodegradable polyester material layer with an adhesive and bond it to the aluminized layer of the aluminized polyethylene film layer to obtain a three-layer composite structure;

[0027] S3. Curing the three-layer composite structure obtained by S2 at 40-60℃ for 24-48 hours yields an environmentally friendly composite hose with aluminum-plated PE as the middle layer.

[0028] Furthermore, the bonding of S2 is completed under a pressure of 5-10 MPa and a temperature of 50-70°C.

[0029] Furthermore, the three-layer composite structure in S3, after curing, is cut, rolled, and heat-sealed to form a flexible hose. The heat-sealing temperature is 80-100℃, and the heat-sealing pressure is 0.3-0.6MPa.

[0030] Furthermore, the adhesive is a water-based polyurethane adhesive.

[0031] In the environmentally friendly composite hose disclosed in this invention, an anti-UV aging agent is a key component, primarily used to protect the outer layer of the hose from degradation caused by UV radiation. This aging agent plays a role in photostability and anti-oxidation in the composite hose, thereby extending the material's lifespan and maintaining its environmental performance. The structure of the anti-UV aging agent includes a large conjugated system, a multi-hydroxyl structure, and a cyano structure. The large conjugated system is the core of this aging agent; it absorbs ultraviolet light (UV-A and UV-B bands, approximately 280-400 nm) through a broad π-π conjugated network. When UV radiation irradiates the hose surface, the conjugated structure acts as an "energy absorber," converting high-energy UV photons into low-energy heat or fluorescence before releasing them, thus preventing UV radiation from directly attacking the polyester molecular chain and avoiding the breakage and cross-linking degradation of the polymer backbone. The multiple hydroxyl groups in the molecule provide free radical capture and hydrogen bond stabilization functions. When UV radiation induces the generation of free radicals in the material, the hydroxyl groups adsorb these highly reactive free radicals through hydrogen bonding, forming stable intermediates and interrupting the free radical chain reaction, which significantly slows down the oxidative degradation process. Meanwhile, the strong polarity of the hydroxyl group facilitates the formation of intermolecular hydrogen bonds, enhancing the dispersibility and thermal stability of the aging agent in the anti-aging layer. The cyano group, as a strong electron acceptor, functions through a photoquenching mechanism, capturing the energy of excited-state molecules and converting it into harmless vibrational energy or releasing it through electron transfer or energy transfer processes. The synergistic effect (rather than isolated functions) of these structural elements is key to the high efficiency of this aging agent: the large conjugated structure acts as the main absorber, the multi-hydroxyl structure provides an antioxidant buffer, and the cyano structure assists in quenching residual excited states.

[0032] The present invention comprises a three-layer structure—inner, middle, and outer—that forms a synergistic environmentally friendly design. The inner layer (biodegradable polyester layer) provides basic barrier properties and biodegradability, decomposing in the natural environment through microbial action, reducing white pollution. The middle layer, in direct contact with the aluminized surface, enhances the continuity of barrier performance. The aluminized PE film layer in the middle layer reflects ultraviolet light and blocks oxygen and water vapor, solving the problem of short shelf life in traditional flexible hoses. The PE substrate provides flexibility and an adhesive interface; the inward design of the aluminized layer protects the contents of the inner layer from photodegradation, while the PE substrate provides an adhesive base for the outer layer. The outer anti-aging layer uses water-based acrylic resin to provide film-forming properties and weather resistance; colorant achieves non-toxic coloring; the anti-UV aging agent absorbs UV light through a large conjugated structure, uses hydroxyl groups to capture free radicals, and cyano groups to quench excited states; all three work synergistically to delay material aging.

[0033] The water-based acrylic resin described in this invention has a high solids content (≥50%), which ensures the density of the coating. Simultaneously, its acid value is in the range of 30-60 mg (KOH / g), which helps to regulate adhesion, thus effectively overcoming the problems of poor adhesion and easy peeling of recycled materials. Nopco 5040 dispersant can improve the dispersion uniformity of the color paste, avoiding color differences and localized performance defects in the coating. Sodium dodecyl sulfonate can be used to eliminate air bubbles generated during stirring, preventing pinholes in the cured coating and ensuring the barrier integrity of the coating. The UV aging agent, through its Formula 1 structure, uses a combination of light absorption and free radical capture to delay the degradation of the outer layer of the coating, solving the problem of short lifespan caused by poor UV resistance in the anti-aging layer.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] 1. Significantly Improved Environmental Performance: This invention significantly reduces dependence on petroleum resources and the risk of environmental pollution by using biodegradable polyester materials (such as polylactic acid) as the inner layer and recycled polyester materials as the outer layer. Traditional technologies rely on non-degradable plastics, which easily cause white pollution; while the design of this invention makes the hose more biodegradable, reducing its ecological footprint.

[0036] 2. Significantly Enhanced UV Aging Resistance: By adding a highly effective UV aging inhibitor, this invention effectively slows down the degradation process of materials under UV radiation. Traditional hoses are susceptible to yellowing and cracking due to UV light on their outer layer; however, the UV aging inhibitor of this invention utilizes light absorption and free radical capture mechanisms to protect the anti-aging layer from damage, significantly extending the service life of the hose and maintaining its appearance stability.

[0037] 3. Comprehensive Performance Synergistic Optimization: The synergistic design of the three-layer structure optimizes the overall performance of the hose. In traditional technologies, the functions of each layer are separated, which can easily lead to insufficient barrier properties or reduced mechanical strength; while the design of this invention, combined with environmentally friendly materials, improves barrier performance, mechanical strength, and product durability, while maintaining flexibility and application adaptability. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of an environmentally friendly composite hose structure with aluminum-plated PE as the intermediate layer, as described in this invention.

[0039] 1 is the inner layer, 2 is the middle layer, and 3 is the outer layer.

[0040] Figure 2 The UV aging protection agent 1 described in this invention 1 HNMR image. Detailed Implementation

[0041] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] Synthesis example 1

[0043] Synthesis of UV aging protectant 1:

[0044]

[0045] Step 1: Under a nitrogen atmosphere, add 30g of raw material 1, 17.71g of raw material 2, 18.13g of anhydrous potassium carbonate, 2.27g of tetra(triphenylphosphine)palladium, and 330g of a mixture of toluene, ethanol, and aqueous solution in a volume ratio of 2:1:1 to the reaction system. Heat to 95°C and reflux for 10 hours. Turn off the heating, cool to room temperature, allow to stand, and separate the liquids. Extract the aqueous phase twice with ethyl acetate, combine the organic phases, dry the organic phase with anhydrous magnesium sulfate, filter, evaporate to dryness, and perform silica gel column chromatography using a mixture of petroleum ether and ethyl acetate as eluent. Evaporate to dryness to obtain 28.36g of intermediate 1.

[0046] Step 2: Under a nitrogen atmosphere, add 28.36 g of intermediate 1, 26.93 g of raw material 3, 0.5 g of tri-tert-butylphosphine, 0.18 g of palladium on carbon, 14.06 g of anhydrous potassium carbonate, and 300 g of toluene to the reaction system. Heat to 120 °C and reflux for 12 hours. After the reaction is complete, lower the temperature slightly, filter with diatomaceous earth, cool the filtrate to room temperature, wash three times with water, retain the organic phase, then extract the aqueous phase with ethyl acetate, combine the organic phases, dry the organic phase with anhydrous magnesium sulfate, filter, evaporate to dryness, and perform silica gel column chromatography with a mixture of petroleum ether and ethyl acetate as eluent. Evaporate to dryness to obtain 37.58 g of UV aging agent 1.

[0047] Structural assessment:

[0048] MS(m / z) of intermediate 1: [M+H] + =558;

[0049] MS (m / z) of UV aging protectant 1: [M+H] + =918;

[0050] UV aging agent 1 1HNMR: δ8.57-8.33(m,5H),8.28(dd,1H),8.23-7.87(m,11H),7.64(d,1H), 7.58-7.43(m,5H),7.26-7.16(m,1H),7.19(s,1H),6.86(dd,1H),5.01-4.8 9(m,1H),4.78-4.68(m,1H),4.68-4.58(m,1H),4.40-4.29(m,1H),3.97-3. 84(m,1H),3.89(s,3H),3.77-3.64(m,2H),3.57-3.37(m,4H),2.49(d,3H).

[0051] Synthesis Example 2-Synthesis Example 4

[0052] In Synthesis Examples 2-4, UV-resistant aging agent 2-UV-resistant aging agent 4 were synthesized sequentially, following the same synthesis method as in Synthesis Example 1, except that raw material 2 was replaced; the rest remained the same as in Synthesis Example 1. Specific structures of raw material 2, UV-resistant aging agent 2-UV-resistant aging agent 4, and MS (m / z): [M+H] are detailed below. + The data is shown in Table 1.

[0053] Table 1. Structures of raw material 2, UV aging agent 2 to UV aging agent 4, and MS (m / z): [M+H] involved in Synthesis Examples 2-4 + data.

[0054]

[0055] Example 1

[0056] This embodiment provides an environmentally friendly composite hose with aluminized PE as the intermediate layer and its preparation method:

[0057] 1. Material preparation:

[0058] Inner layer material: Polylactic acid (PLA) is selected as the biodegradable polyester material layer with a thickness of 25μm and a melt index of 8g / 10min (190℃ / 2.16kg).

[0059] Intermediate layer material: A polyethylene layer with aluminum plating is used, with an aluminum plating thickness of 30nm (facing the inner layer) and a polyethylene substrate thickness of 20μm.

[0060] Outer layer material: The anti-aging layer is weighed by weight as follows: 50 parts of water-based acrylic resin (solid content 55%, acid value 45mg KOH / g), 25 parts of color paste (phthalocyanine green G), 2 parts of dispersant (Nopco 5040 dispersant), 1 part of defoamer (sodium dodecyl sulfonate), 20 parts of deionized water, and 3 parts of anti-ultraviolet aging agent (anti-ultraviolet aging agent 1 prepared in synthesis example 1).

[0061] 2. Preparation of pre-fabricated composite membranes:

[0062] The water-based acrylic resin, color paste, dispersant, defoamer, deionized water and UV aging agent are put into a high-speed disperser and stirred at 1200 r / min for 30 minutes until uniform to obtain an anti-aging layer slurry. The slurry is then coated onto the polyethylene substrate of the intermediate layer (aluminized PE film) using a micro-gravure coating machine with a coating thickness of 15 μm. Subsequently, it is cured in a 70℃ hot air drying oven for 20 minutes to obtain a pre-fabricated composite film.

[0063] 3. Three-layer composite structure molding

[0064] A water-based polyurethane adhesive (coating amount 3g / m²) is applied to the inner layer (PLA membrane) surface. 2 The three-layer composite film is pressed together with the aluminized surface of the middle layer using a composite machine. The process parameters are: pressure: 8MPa, temperature: 60℃, speed: 8m / min. The composite material is then placed in a 50℃ curing chamber for 36 hours to allow the adhesive to fully cross-link. The cured three-layer composite film is then cut into the required width, formed by a spiral tube winding machine, and the tube shoulder is heat-sealed at 90℃ and 0.5MPa to obtain an environmentally friendly composite hose with aluminized PE as the middle layer.

[0065] Examples 2-4

[0066] The preparation of an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer is carried out by referring to the preparation method of Example 1, except that the UV aging agent is replaced in sequence with UV aging agent 2-UV aging agent 4 prepared in Synthesis Examples 2-4, and the rest is the same as in Example 1.

[0067] Comparative Example 1

[0068] The preparation of an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer is the same as in Example 1, except that the UV aging agent is not added.

[0069] Comparative Example 2

[0070] The preparation of an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer is the same as in Example 1, except that the anti-ultraviolet aging agent is replaced with ultraviolet absorber UV326.

[0071] Comparative Example 3

[0072] The preparation of an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer is carried out by referring to the preparation method of Example 1, except that the mass fraction of water-based acrylic resin is replaced with 30 parts, and the rest is the same as in Example 1.

[0073] Comparative Example 4

[0074] The preparation of an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer is carried out by referring to the preparation method of Example 1, except that the mass fraction of water-based acrylic resin is replaced with 80 parts, and the rest is the same as in Example 1.

[0075] Performance testing:

[0076] 1. Tear strength: In accordance with the standard GB / T1040.2-2006, a 12cm×10cm×0.5mm sample was taken and tested using a universal electronic testing machine to test the mechanical properties of an environmentally friendly composite hose with an aluminum-plated PE intermediate layer prepared in the examples and comparative examples. The data are shown in Table 2.

[0077] 2. Ultraviolet aging test: The environmentally friendly composite hose with aluminum-plated PE as the intermediate layer prepared in the examples and comparative examples was irradiated under a 315nm ultraviolet lamp for 500 hours, and the surface was observed to see if it turned yellow. The data are shown in Table 2.

[0078] 3. Oxygen permeability: The oxygen permeability of an environmentally friendly composite hose with an aluminized PE intermediate layer prepared in the examples and comparative examples was tested according to the standard GB / T29336-2012. The data are shown in Table 2.

[0079] Table 2. Performance test data of an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer prepared in the examples and comparative examples.

[0080] Tear strength (MPa) UV aging color <![CDATA[Oxygen transmission rate m 2 ·24h·0.1MPa]]> Example 1 128.5 It did not turn yellow, and the surface showed no change. 2.75 Example 2 127.9 It did not turn yellow, and the surface showed no change. 2.78 Example 3 128.2 It did not turn yellow, and the surface showed no change. 2.76 Example 4 127.7 It did not turn yellow, and the surface showed no change. 2.80 Comparative Example 1 117.3 Severe yellowing, surface cracking 2.50 Comparative Example 2 115.6 Slight yellowing, no surface deformation 2.70 Comparative Example 3 114.8 Slight yellowing, no surface deformation 1.80 Comparative Example 4 112.5 Severely yellowed, with slight surface cracking 1.64

[0081] All examples (samples using different UV aging agents) exhibited excellent tear strength and UV aging resistance, demonstrating high and stable tear strength with no significant yellowing or deformation after UV aging. This indicates that the UV aging agents effectively improved the mechanical properties and durability of the material. In contrast, the comparative example showed a significant decrease in tear strength and exhibited varying degrees of yellowing and brittleness after UV aging, suggesting that missing or improper material proportions impaired the integrity and anti-aging ability of the hose. Furthermore, the examples showed relatively high oxygen permeability, while the comparative example showed decreased permeability with changes in resin content. This reflects that changes in material composition can affect the balance of barrier performance. Overall, the examples demonstrated superior comprehensive performance, highlighting the crucial role of UV aging agents and optimized resin content in environmentally friendly composite hoses.

[0082] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An environmentally friendly composite hose with aluminized PE as the intermediate layer, characterized in that, From the inside out, it includes: inner layer (1): biodegradable polyester material layer; middle layer (2): aluminum-plated polyethylene film layer, including aluminum plating layer and polyethylene layer, with the aluminum plating layer facing the inner layer (1); outer layer (3): anti-aging layer. The anti-aging layer comprises the following components by weight: 40-65 parts of water-based acrylic resin, 15-35 parts of color paste, 1-3 parts of dispersant, 0.5-2 parts of defoamer, 10-25 parts of deionized water, and 1-5 parts of anti-UV aging agent. The UV-protective aging agent is Formula 1; R1 is selected from: methyl, ethyl, tert-butyl, methoxy.

2. The environmentally friendly composite hose with aluminized PE as the intermediate layer as described in claim 1, characterized in that, The solids content of the waterborne acrylic resin is ≥50%.

3. The environmentally friendly composite hose with aluminized PE as the intermediate layer as described in claim 1, characterized in that, The dispersant is specifically Nopco 5040 dispersant; the defoamer is specifically sodium dodecyl sulfonate.

4. The environmentally friendly composite hose with aluminized PE as the intermediate layer as described in claim 1, characterized in that, The method for preparing the anti-aging layer is as follows: the water-based acrylic resin, color paste, dispersant, defoamer, deionized water and anti-UV aging agent are mixed and stirred evenly to form the anti-aging layer slurry; the anti-aging layer slurry is coated on the surface of the intermediate layer (2) and dried and cured at 60-80℃ to obtain the anti-aging layer.

5. The environmentally friendly composite hose with aluminized PE as the intermediate layer as described in claim 1, characterized in that, The biodegradable polyester material layer is made of polylactic acid.

6. The environmentally friendly composite hose with aluminized PE as the intermediate layer as described in claim 1, characterized in that, The aluminum plating layer in the aluminized polyethylene film has a thickness of 20-40 nm and the polyethylene layer has a thickness of 10-30 μm.

7. A method for preparing an environmentally friendly composite hose with an aluminized PE intermediate layer as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. The anti-aging slurry is applied to the surface of the polyethylene layer and dried and cured at 60-80℃ to obtain a prefabricated composite film; S2. Coat the surface of the biodegradable polyester material layer with an adhesive and bond it to the aluminized layer of the aluminized polyethylene film layer to obtain a three-layer composite structure; S3. Curing the three-layer composite structure at 40-60℃ for 24-48 hours yields an environmentally friendly composite hose with aluminum-plated PE as the intermediate layer.

8. The method for preparing an environmentally friendly composite hose with aluminized PE as the intermediate layer according to claim 7, characterized in that, The bonding in S2 is completed under a pressure of 5-10 MPa and a temperature of 50-70°C.

9. The method for preparing an environmentally friendly composite hose with aluminized PE as the intermediate layer according to claim 7, characterized in that, The three-layer composite structure in S3, after curing, is cut, rolled, and heat-sealed to form a flexible hose. The heat-sealing temperature is 80-100℃, and the heat-sealing pressure is 0.3-0.6MPa.

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