Easily separable environment-friendly cosmetic packaging bottle based on integrated composite structure and forming process thereof

Abstract

The application discloses an easily-separated environment-friendly cosmetic packaging bottle based on an integrated composite structure and a forming process thereof, and relates to the technical field of environment-friendly materials.The forming process comprises the following steps: 1) base material treatment; 2) inner layer coating; and 3) outer wall gold plating.The inner layer coating is a hydrolysable coating, the main body of which is an antibacterial modified starch, which is acetalized by cinnamyl aldehyde and grafted with a quaternary ammonium salt monomer to form a three-dimensional cross-linked network, and a latent acid agent, pyridinium p-toluenesulfonate, is added.The coating has antibacterial and hydrophobic properties in normal state; when recycled, the coating is placed in hot water at a temperature higher than 60 DEG C, the latent acid agent is decomposed to release H + , and the catalytic acetal bond is hydrolyzed, so that the network is disintegrated, and the coating is quickly separated from the base material.The application realizes the unity of stable performance during the use cycle and easy separation during recycling of the packaging bottle, simplifies the recycling process of the ABS base material, and has remarkable environmental protection and practical values.

Description

Technical Field

[0001] This invention relates to the field of environmentally friendly materials technology, and in particular to easily separable environmentally friendly cosmetic packaging bottles based on an integrated composite structure and their molding process. Background Technology

[0002] In the medical field, the cleanliness and sterility of medical clothing, such as surgical gowns, protective suits, and medical staff uniforms, directly affect the effectiveness of preventing cross-infection between medical staff and patients. As a core protective barrier during the storage, transportation, and pre-treatment stages of medical clothing, packaging film must be designed to strictly meet four core requirements: contamination prevention, ease of handling, antibacterial stability, and mechanical reliability. With the continuous improvement of medical infection control standards, existing medical clothing packaging films have gradually revealed several technical deficiencies: Firstly, insoluble films (such as polyethylene films) require manual unsealing and cleaning, which can easily lead to secondary infections; simple water-soluble starch films are prone to absorbing moisture and dissolving at room temperature, and have poor mechanical properties, making them difficult to store and transport, highlighting the contradiction between water solubility and stability.

[0003] Secondly, antibacterial agents are mostly physically mixed, which makes them prone to volatilization and migration. Their effectiveness decreases over time, and single-component antibacterial agents have a narrow spectrum, making them difficult to deal with complex medical flora.

[0004] Third, traditional water-soluble membrane molecules are linear and are held together only by weak interactions, making them mechanically weak and prone to tearing and damage during packaging and transportation.

[0005] It is difficult to meet the clinical demand for efficient, safe and convenient packaging solutions, and these pain points are mutually restrictive, which existing technologies cannot address simultaneously, so new technological solutions are urgently needed. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing an easily separable, environmentally friendly cosmetic packaging bottle based on an integrated composite structure and its molding process.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: This invention first proposes an easily separable, environmentally friendly cosmetic packaging bottle based on an integrated composite structure, comprising a three-layer structure integrally molded from the inside out, namely: Substrate layer: ABS resin layer, with a melt flow rate of 1.6-2.0 g / 10 min at 220℃ and a heat distortion temperature ≥90℃; Hydrolyzable inner wall coating: prepared from antibacterial modified starch, adhesion promoter, hydrophobic modifier, thickener and preservative in a mass ratio of 25-30:1.5-2.5:0.8-1.2:0.3-0.7:0.3-0.7, with a dry film thickness of 0.2-0.3 mm; Hot stamping layer: includes a PET carrier layer, a nickel-free aluminum plating layer and a hot melt adhesive layer that are laminated in sequence, wherein the thickness of the PET carrier layer is 10-15μm; The adhesion promoter is a PU dispersion; the hydrophobic modifier is a long-chain alkyl silane; the thickener is sodium hydroxymethyl cellulose; the preservative is phenoxyethanol; the hot melt adhesive layer is an acrylic resin adhesive layer with a thickness of 3-5 μm; and the nickel-free aluminum plating layer has a thickness of 0.1-0.3 μm.

[0008] Preferably, the method for preparing the antibacterial modified starch includes the following steps: ① The acetal reaction of hydroxypropyl starch with cinnamaldehyde: Add dimethyl sulfoxide to the reaction vessel, start stirring, slowly add hydroxypropyl starch, heat to 80°C, maintain the temperature and stir until the starch is completely dissolved, and obtain a transparent and viscous starch solution. The temperature inside the reactor was lowered to 50°C, p-toluenesulfonic acid was added, and the mixture was stirred to disperse it evenly. Cinnamaldehyde was slowly added dropwise. After the addition was complete, the temperature was maintained at 50°C, and the reaction was carried out in the dark for 12 hours to obtain cinnamaldehyde starch acetal. A nucleophilic hydroxyl oxygen atom on hydroxypropyl starch attacks the activated carbonyl carbon atom, undergoing nucleophilic addition to form a hemiacetal intermediate. Under acid catalysis, the hydroxyl group of this intermediate is protonated to form a favorable leaving group (H₂O), which then loses a water molecule to generate a carbocation. A hydroxyl group on another starch chain attacks this carbocation, undergoing another nucleophilic addition. Finally, the oxygen atom loses a proton (H₂O). + This process generates the final stable acetal product and regenerates the acid catalyst (H). + ), thus completing the catalytic cycle.

[0009] That is, a cinnamaldehyde molecule reacts with the hydroxyl groups on two starch chains to form an acetal bridge, while losing one molecule of water.

[0010] This allows cinnamaldehyde to be firmly suspended on the starch backbone via stable COC bonds, while retaining its terminal olefin (C=C) for subsequent polymerization.

[0011] After the reaction is complete, anhydrous sodium carbonate is slowly added to the reaction vessel to neutralize the acid in the system until it is neutral. The cinnamaldehyde starch acetal was transferred to a precipitation tank containing ethanol, stirred vigorously to allow precipitation, centrifuged to separate the precipitate, collected and vacuum dried to obtain hydroxypropyl starch-cinnamaldehyde acetal. ②Grafted copolymerization of quaternary ammonium salts: Add N,N-dimethylformamide to the polymerization reactor, start stirring, add hydroxypropyl starch-cinnamaldehyde acetal, heat to 70°C, and stir until completely dissolved; Methacryloxyethyltrimethylammonium chloride and azobisisobutyronitrile were added to a reaction vessel; nitrogen was continuously introduced into the reaction vessel to remove oxygen, and then the inlet and outlet were closed to maintain a slight positive pressure in the system; the reaction was carried out at 70°C under nitrogen protection for 8 hours to obtain a quaternary ammonium salt copolymer. This reaction is a free radical copolymerization, initiated by free radicals generated from the decomposition of azobisisobutyronitrile. The double bonds of cinnamaldehyde and the double bonds on the monomers open under the initiation of free radicals and connect with each other to form a copolymer with C-C bonds as the main chain. The quaternary ammonium salt groups on methacryloyloxyethyltrimethylammonium chloride are introduced into the polymer chain.

[0012] After the reaction was completed, the quaternary ammonium salt copolymer was cooled to room temperature, poured into acetone, and stirred rapidly to precipitate the copolymer. The precipitate was filtered, collected, washed with acetone, and dried under vacuum to obtain the modified starch copolymer, i.e., antibacterial modified starch.

[0013] Preferably, in step ①, the hydroxypropyl molar substitution degree of hydroxypropyl starch needs to be ≥0.1, that is, an average of 0.1 hydroxypropyl groups are introduced on each unit of glucose residue; the solid content of the starch solution is 10%; the mass of added p-toluenesulfonic acid is 1%-2% of the mass of hydroxypropyl starch; and the mass ratio of hydroxypropyl starch to cinnamaldehyde is 12-15:5.

[0014] Preferably, in step ②, the mass ratio of cinnamaldehyde starch acetal to methacryloyloxyethyltrimethylammonium chloride is 70:30-40; methacryloyloxyethyltrimethylammonium chloride is added in the form of an 80% (w / w) aqueous solution of methacryloyloxyethyltrimethylammonium chloride; the amount of azobisisobutyronitrile added is 0.3% of the total mass of cinnamaldehyde starch acetal and methacryloyloxyethyltrimethylammonium chloride, and it is added in the form of a 10% (w / w) N,N-dimethylformamide solution of azobisisobutyronitrile.

[0015] This invention also proposes a molding process for the aforementioned easily separable environmentally friendly cosmetic packaging bottle based on an integrated composite structure, characterized by the following steps: S1. Substrate layer injection molding: ABS resin raw material is added to the injection molding machine, melted, injected, held under pressure, cooled and then demolded to obtain ABS bottle substrate; S2. Substrate pretreatment: The inner wall of the ABS bottle substrate is subjected to plasma treatment and primer treatment, and the outer wall of the ABS bottle substrate is subjected to corona treatment and dust removal treatment. S3. Inner wall coating: Antibacterial modified starch is prepared into starch casting liquid, and the casting liquid is coated onto the inner wall of ABS bottle substrate by dip coating method. After pre-drying and gradient drying, a hydrolyzable inner wall coating is formed. S4. Hot stamping on the outer wall: The environmentally friendly hot stamping foil is laminated to the outer wall of the ABS bottle substrate using a hot stamping process to form an environmentally friendly hot stamping layer. S5. Finished Product Processing: Perform performance testing on the composite molded packaging bottles, remove unqualified products, and then package and store them in the warehouse.

[0016] The injection molding machine parameters for S1 are set as follows: front barrel temperature 200-210℃, middle barrel temperature 210-220℃, rear barrel temperature 190-200℃, mold temperature 50-60℃, injection pressure 80-100MPa, holding pressure 40-60MPa, holding time 15-20s, and cooling time 20-25s.

[0017] According to step S3, the antibacterial modified starch is made into a hydrolyzable inner wall coating, specifically including the following steps: Take the modified starch copolymer and add it to the mixing tank equipped with a high-speed disperser. Add deionized water and adjust the solid content of the system. Disperse at high speed for 2-2.5 hours to form a uniform viscous liquid. Reduce the speed and slowly add p-toluenesulfonate pyridinium salt. Continue stirring for 1 hour to ensure that p-toluenesulfonate pyridinium salt is completely and uniformly dispersed. Add adhesion promoter, hydrophobic modifier, thickener and preservative to obtain starch casting solution. The starch casting solution was degassed using a centrifugal degassing machine and then transferred to a casting machine. The casting machine was started to coat the starch casting solution onto the inner wall of the ABS bottle substrate, resulting in a hydrolyzable inner wall coating.

[0018] Preferably, the solid content of the starch casting solution is 40%, and the mass ratio of the modified starch copolymer to p-toluenesulfonate pyridinium salt is 10:0.6-0.8; Preferably, the dip coating process parameters of S3 are: dip coating speed 4-6 cm / s, residence time 8-12 s; the gradient drying parameters are: first zone 40℃ residence time 12-18 min, second zone 50℃ residence time 10-15 min, third zone 60℃ residence time 6-10 min.

[0019] Preferably, in step S4, the hot stamping process parameters are: hot stamping temperature 75-80℃, hot stamping pressure 0.3-0.5MPa, hot stamping speed 1.8-2.2m / min, hot stamping time 0.8-1s, and cooling with 40℃ cold air for 4-6s after hot stamping.

[0020] Each hydroxypropyl starch-cinnamaldehyde acetal macromolecular chain is grafted with multiple cinnamaldehyde units, and each cinnamaldehyde unit carries a polymerizable olefin double bond, thus providing a large number of reaction sites for methacryloyloxyethyltrimethylammonium chloride. While loading quaternary ammonium salt functional groups to play a bactericidal role, methacryloyloxyethyltrimethylammonium chloride also plays a role in crosslinking starch molecular chains. This many-to-many reaction mode will theoretically eventually form a huge, three-dimensional, insoluble and infusible network polymer crosslinking structure. However, when the coating is placed in hot water above 60°C, the latent acid agent p-toluenesulfonic acid pyridinium salt undergoes thermal decomposition, releasing the strong protic acid p-toluenesulfonic acid, and the released H... + The hydrolysis of the acetal bond leads to the reverse reaction of stage ① acetalization, generating the original hydroxypropyl starch and cinnamaldehyde. The network structure of the coating is destroyed, and acid hydrolysis occurs. Meanwhile, when the molar substitution degree of hydroxypropyl starch is greater than 0.1, it can gelatinize in hot water at 60-65℃, and the molecular chains absorb water, swell, unfold, and completely dissolve under the action of water. At room temperature, this cross-linked structure significantly improves the coating's mechanical strength, density, and acid and alkali resistance, enabling it to withstand mechanical stress during encapsulation, storage, and use, remaining intact and insoluble. In 60°C hot water, acid hydrolysis breaks acetal bonds and some glycosidic bonds, but the cross-linking points (CC bonds) remain very stable and do not break. However, once enough acetal bonds and starch chains break, the entire three-dimensional network disintegrates into multiple fragments bound by the cross-linking points, achieving rapid swelling and fragmented dissolution. The coating then detaches from the ABS substrate, allowing for substrate recycling.

[0021] Compared with the prior art, the beneficial effects of the present invention are: First, by constructing a temperature-responsive cross-linking-hydrolysis dynamic network, the stability of the coating during service and rapid, controllable peeling during recycling were achieved. The core component of the hydrolyzable inner wall coating, antibacterial modified starch, is a three-dimensional cross-linked network constructed from acetal bonds and C / C covalent bonds. Under room temperature and normal operating conditions, the dense C / C bond network and stable acetal structure endow the coating with excellent mechanical strength, chemical resistance, and strong adhesion to the ABS substrate, ensuring the integrity of the packaging bottle during filling, storage, and use. When recycling is required, placing the packaging bottle in hot water at >60°C causes the uniformly distributed latent acid agent (pyridinium salt of p-toluenesulfonate) in the coating to decompose upon heating, releasing a strong protic acid (H2O). + H +The highly efficient catalytic hydrolysis of acetal bonds breaks the chemical bridge connecting starch chains and cinnamaldehyde derivatives. Simultaneously, the thermal environment promotes the gelatinization and swelling of hydroxypropyl starch molecular chains through water absorption. Under the synergistic effect of these two actions, the originally robust three-dimensional network disintegrates at the cross-linking points, breaking into tiny fragments bound by C-C bonds. These fragments rapidly swell and disperse in water, allowing the coating to quickly and completely detach from the ABS substrate surface, greatly simplifying the subsequent substrate cleaning and recycling process.

[0022] Secondly, by chemically grafting antibacterial and hydrophobic functional groups to the starch backbone, a long-lasting and stable surface function of the coating is achieved. The antibacterial and hydrophobic properties of the coating do not rely on physical blending, but rather on permanent covalent bonding. During preparation, cinnamaldehyde is suspended from the starch chain via a stable COC bond through an acetal reaction. The terminal olefin double bond then undergoes free radical copolymerization with a quaternary ammonium salt monomer (methacryloyloxyethyltrimethylammonium chloride) to form a graft copolymer with a C / C bond as the main chain. This design allows the bactericidal quaternary ammonium salt cationic groups to directly become part of the polymer side chain through strong C / C bonds, avoiding the migration and loss of small-molecule antibacterial agents and providing long-lasting and efficient contact antibacterial capabilities. Simultaneously, long-chain alkylsilane hydrophobic modifiers combine with the coating system through chemical reactions, forming stable low surface energy regions on and within the coating surface. This endows the coating with excellent hydrophobic properties, effectively resisting the wetting and residue of contents and further enhancing water resistance. This chemically bonded functionalization method ensures the stable existence and efficient performance of functional groups throughout the coating's service life.

[0023] Third, by adopting a bio-based core and environmentally friendly composite process, the entire chain from raw materials to end products achieves green sustainability. This solution incorporates environmental protection principles in multiple stages. First, the inner coating uses renewable modified starch as the main raw material, replacing traditional petroleum-based polymers and reducing the carbon footprint at the source. Second, the hot stamping layer uses nickel-free aluminum plating and acrylic resin hot melt adhesive, avoiding the use of heavy metal nickel and the volatile organic compound (VOC) pollution from solvent-based adhesives. The composite process is completed through a precisely controlled hot stamping process, which is efficient and clean. Finally, the entire packaging bottle is integrally molded, with a streamlined structure. This not only reduces material and energy consumption from assembling multiple parts but also, through the controllable hydrolysis characteristics of the inner coating, ensures that the ABS substrate is virtually uncontaminated during recycling, allowing for high-quality recycling. This composite structural design of "bio-based functional coating + easily recyclable substrate + clean exterior" systematically solves the pain points of difficult recycling and mixed materials in traditional cosmetic packaging while ensuring product performance and aesthetics. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the environmentally friendly cosmetic packaging bottle produced by this invention; Among them, ① hydrolyzable inner wall coating; ② substrate layer; ③ hot stamping layer. Detailed Implementation

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with existing known technologies. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0026] Example 1: An easily separable, environmentally friendly cosmetic packaging bottle based on an integrated composite structure, comprising a three-layer structure integrally molded from the inside out, namely: Substrate layer: ABS resin layer, melt flow rate at 220℃ is 1.6-2.0g / 10min, heat distortion temperature ≥90℃; Hydrolyzable inner wall coating: prepared from antibacterial modified starch, adhesion promoter, hydrophobic modifier, thickener and preservative in a mass ratio of 30:1.5:1.2:0.3:0.7, with a dry film thickness of 0.2-0.3 mm; Hot stamping layer: includes a PET carrier layer, a nickel-free aluminum plating layer and a hot melt adhesive layer that are laminated in sequence, wherein the thickness of the PET carrier layer is 10-15μm; The adhesion promoter is a PU dispersion; the hydrophobic modifier is a long-chain alkyl silane; the thickener is sodium hydroxymethyl cellulose; the preservative is phenoxyethanol; the hot melt adhesive layer is an acrylic resin adhesive layer with a thickness of 3-5 μm; and the nickel-free aluminum plating layer has a thickness of 0.1-0.3 μm.

[0027] The method for preparing the antibacterial modified starch includes the following steps: ① The acetal reaction of hydroxypropyl starch with cinnamaldehyde: Add dimethyl sulfoxide to the reaction vessel, start stirring, slowly add hydroxypropyl starch, heat to 80°C, maintain the temperature and stir until the starch is completely dissolved, and obtain a transparent and viscous starch solution. The temperature inside the reactor was lowered to 50°C, p-toluenesulfonic acid was added, and the mixture was stirred to disperse it evenly. Cinnamaldehyde was slowly added dropwise. After the addition was complete, the temperature was maintained at 50°C and the reaction was carried out in the dark for 12 hours to obtain cinnamaldehyde starch acetal. After the reaction is complete, anhydrous sodium carbonate is slowly added to the reaction vessel to neutralize the acid in the system until it is neutral. The cinnamaldehyde starch acetal was transferred to a precipitation tank containing ethanol, stirred vigorously to allow precipitation, centrifuged to separate the precipitate, collected and vacuum dried to obtain hydroxypropyl starch-cinnamaldehyde acetal. ②Grafted copolymerization of quaternary ammonium salts: Add N,N-dimethylformamide to the polymerization reactor, start stirring, add hydroxypropyl starch-cinnamaldehyde acetal, heat to 70°C, and stir until completely dissolved; Methacryloxyethyltrimethylammonium chloride and azobisisobutyronitrile were added to a reactor; nitrogen was continuously introduced into the reactor to remove oxygen, and then the inlet and outlet were closed to maintain a slight positive pressure in the system; the reaction was carried out at 70°C under nitrogen protection for 8 hours to obtain a quaternary ammonium salt copolymer. After the reaction was completed, the quaternary ammonium salt copolymer was cooled to room temperature, poured into acetone, and stirred rapidly to precipitate the copolymer. The precipitate was filtered, collected, washed with acetone, and dried under vacuum to obtain the modified starch copolymer, i.e., antibacterial modified starch.

[0028] In ①, the molar substitution degree of hydroxypropyl starch must be ≥0.1, that is, an average of 0.1 hydroxypropyl groups are introduced on each unit of glucose residue; the solid content of the starch solution is 10%; the mass of p-toluenesulfonic acid added is 2% of the mass of hydroxypropyl starch; and the mass ratio of hydroxypropyl starch to cinnamaldehyde is 12:5.

[0029] In step ②, the mass ratio of cinnamaldehyde starch acetal to methacryloyloxyethyltrimethylammonium chloride is 70:30-40; methacryloyloxyethyltrimethylammonium chloride is added in the form of an 80% (w / w) aqueous solution of methacryloyloxyethyltrimethylammonium chloride; the amount of azobisisobutyronitrile added is 0.3% of the total mass of cinnamaldehyde starch acetal and methacryloyloxyethyltrimethylammonium chloride, and it is added in the form of a 10% (w / w) N,N-dimethylformamide solution of azobisisobutyronitrile.

[0030] The molding process for easily separable, environmentally friendly cosmetic packaging bottles based on an integrated composite structure includes the following steps: S1. Substrate layer injection molding: ABS resin raw material is added to the injection molding machine, melted, injected, held under pressure, cooled and then demolded to obtain ABS bottle substrate; S2. Substrate pretreatment: The inner wall of the ABS bottle substrate is subjected to plasma treatment and primer treatment, and the outer wall of the ABS bottle substrate is subjected to corona treatment and dust removal treatment. S3. Inner wall coating: Antibacterial modified starch is prepared into starch casting liquid, and the casting liquid is coated onto the inner wall of ABS bottle substrate by dip coating method. After pre-drying and gradient drying, a hydrolyzable inner wall coating is formed. S4. Hot stamping on the outer wall: The environmentally friendly hot stamping foil is laminated to the outer wall of the ABS bottle substrate using a hot stamping process to form an environmentally friendly hot stamping layer. S5. Finished Product Processing: Perform performance testing on the composite molded packaging bottles, remove unqualified products, and then package and store them in the warehouse.

[0031] The injection molding machine parameters of S1 are set as follows: front barrel temperature 200℃, middle barrel temperature 210℃, rear barrel temperature 190℃, mold temperature 50℃, injection pressure 80MPa, holding pressure 40MPa, holding time 20s, and cooling time 20s.

[0032] In step S3, the antibacterial modified starch is made into a hydrolyzable inner wall coating, specifically including the following steps: Take the modified starch copolymer and add it to the mixing tank equipped with a high-speed disperser. Add deionized water, adjust the solid content of the system, and disperse at high speed for 2 hours to form a uniform viscous liquid. Reduce the speed and slowly add p-toluenesulfonate pyridinium salt. Continue stirring for 1 hour to ensure that p-toluenesulfonate pyridinium salt is completely and uniformly dispersed. Add adhesion promoter, hydrophobic modifier, thickener and preservative to obtain starch casting liquid. The starch casting solution was degassed using a centrifugal degassing machine and then transferred to a casting machine. The casting machine was started to coat the starch casting solution onto the inner wall of the ABS bottle substrate, resulting in a hydrolyzable inner wall coating.

[0033] The solid content of the starch casting solution is 40%, and the mass ratio of modified starch copolymer to p-toluenesulfonic acid pyridinium salt is 10:0.8. The dip coating process parameters for S3 are: dip coating speed 4cm / s, residence time 12s; the gradient drying parameters are: first zone 40℃ residence time 12min, second zone 50℃ residence time 15min, third zone 60℃ residence time 6min.

[0034] In S4, the hot stamping process parameters are: stamping temperature 80℃, stamping pressure 0.5MPa, stamping speed 2.2m / min, stamping time 1s, and cooling with 40℃ cold air for 6s after stamping.

[0035] Example 2: An easily separable, environmentally friendly cosmetic packaging bottle based on an integrated composite structure, comprising a three-layer structure integrally molded from the inside out, as follows: Substrate layer: ABS resin layer, melt flow rate at 220℃ is 1.6-2.0g / 10min, heat distortion temperature ≥90℃; Hydrolyzable inner wall coating: prepared from antibacterial modified starch, adhesion promoter, hydrophobic modifier, thickener and preservative in a mass ratio of 28:2:1:0.5:0.5, with a dry film thickness of 0.2-0.3 mm; Hot stamping layer: includes a PET carrier layer, a nickel-free aluminum plating layer and a hot melt adhesive layer that are laminated in sequence, wherein the thickness of the PET carrier layer is 10-15μm; The adhesion promoter is a PU dispersion; the hydrophobic modifier is a long-chain alkyl silane; the thickener is sodium hydroxymethyl cellulose; the preservative is phenoxyethanol; the hot melt adhesive layer is an acrylic resin adhesive layer with a thickness of 3-5 μm; and the nickel-free aluminum plating layer has a thickness of 0.1-0.3 μm.

[0036] The method for preparing the antibacterial modified starch includes the following steps: ① The acetal reaction of hydroxypropyl starch with cinnamaldehyde: Add dimethyl sulfoxide to the reaction vessel, start stirring, slowly add hydroxypropyl starch, heat to 80°C, maintain the temperature and stir until the starch is completely dissolved, and obtain a transparent and viscous starch solution. The temperature inside the reactor was lowered to 50°C, p-toluenesulfonic acid was added, and the mixture was stirred to disperse it evenly. Cinnamaldehyde was slowly added dropwise. After the addition was complete, the temperature was maintained at 50°C, and the reaction was carried out in the dark for 12 hours to obtain cinnamaldehyde starch acetal. After the reaction is complete, anhydrous sodium carbonate is slowly added to the reaction vessel to neutralize the acid in the system until it is neutral. The cinnamaldehyde starch acetal was transferred to a precipitation tank containing ethanol, stirred vigorously to allow precipitation, centrifuged to separate the precipitate, collected and vacuum dried to obtain hydroxypropyl starch-cinnamaldehyde acetal. ②Grafted copolymerization of quaternary ammonium salts: Add N,N-dimethylformamide to the polymerization reactor, start stirring, add hydroxypropyl starch-cinnamaldehyde acetal, heat to 70°C, and stir until completely dissolved; Methacryloxyethyltrimethylammonium chloride and azobisisobutyronitrile were added to a reactor; nitrogen was continuously introduced into the reactor to remove oxygen, and then the inlet and outlet were closed to maintain a slight positive pressure in the system; the reaction was carried out at 70°C under nitrogen protection for 8 hours to obtain a quaternary ammonium salt copolymer. After the reaction was completed, the quaternary ammonium salt copolymer was cooled to room temperature, poured into acetone, and stirred rapidly to precipitate the copolymer. The precipitate was filtered, collected, washed with acetone, and dried under vacuum to obtain the modified starch copolymer, i.e., antibacterial modified starch.

[0037] In ①, the hydroxypropyl molar substitution degree of hydroxypropyl starch must be ≥0.1, that is, an average of 0.1 hydroxypropyl groups are introduced on each unit of glucose residue; the solid content of the starch solution is 10%; the mass of p-toluenesulfonic acid added is 1.5% of the mass of hydroxypropyl starch; and the mass ratio of hydroxypropyl starch to cinnamaldehyde is 13:5.

[0038] In step ②, the mass ratio of cinnamaldehyde starch acetal to methacryloyloxyethyltrimethylammonium chloride is 70:35; methacryloyloxyethyltrimethylammonium chloride is added in the form of an 80% (w / w) aqueous solution of methacryloyloxyethyltrimethylammonium chloride; the amount of azobisisobutyronitrile added is 0.3% of the total mass of cinnamaldehyde starch acetal and methacryloyloxyethyltrimethylammonium chloride, and it is added in the form of a 10% (w / w) N,N-dimethylformamide solution of azobisisobutyronitrile.

[0039] The molding process for easily separable, environmentally friendly cosmetic packaging bottles based on an integrated composite structure includes the following steps: S1. Substrate layer injection molding: ABS resin raw material is added to the injection molding machine, melted, injected, held under pressure, cooled and then demolded to obtain ABS bottle substrate; S2. Substrate pretreatment: The inner wall of the ABS bottle substrate is subjected to plasma treatment and primer treatment, and the outer wall of the ABS bottle substrate is subjected to corona treatment and dust removal treatment. S3. Inner wall coating: Antibacterial modified starch is prepared into starch casting liquid, and the casting liquid is coated onto the inner wall of ABS bottle substrate by dip coating method. After pre-drying and gradient drying, a hydrolyzable inner wall coating is formed. S4. Hot stamping on the outer wall: The environmentally friendly hot stamping foil is laminated to the outer wall of the ABS bottle substrate using a hot stamping process to form an environmentally friendly hot stamping layer. S5. Finished Product Processing: Perform performance testing on the composite molded packaging bottles, remove unqualified products, and then package and store them in the warehouse.

[0040] The injection molding machine parameters of S1 are set as follows: front barrel temperature 200℃, middle barrel temperature 210℃, rear barrel temperature 190℃, mold temperature 50℃, injection pressure 80MPa, holding pressure 40MPa, holding time 20s, and cooling time 20s.

[0041] In step S3, the antibacterial modified starch is made into a hydrolyzable inner wall coating, specifically including the following steps: Take the modified starch copolymer and add it to the mixing tank equipped with a high-speed disperser. Add deionized water, adjust the solid content of the system, and disperse at high speed for 2 hours to form a uniform viscous liquid. Reduce the speed and slowly add p-toluenesulfonate pyridinium salt. Continue stirring for 1 hour to ensure that p-toluenesulfonate pyridinium salt is completely and uniformly dispersed. Add adhesion promoter, hydrophobic modifier, thickener and preservative to obtain starch casting liquid. The starch casting solution was degassed using a centrifugal degassing machine and then transferred to a casting machine. The casting machine was started to coat the starch casting solution onto the inner wall of the ABS bottle substrate, resulting in a hydrolyzable inner wall coating.

[0042] The solid content of the starch casting solution is 40%, and the mass ratio of the modified starch copolymer to p-toluenesulfonic acid pyridinium salt is 10:0.7. The dip coating process parameters for S3 are: dip coating speed 4cm / s, residence time 12s; the gradient drying parameters are: first zone 40℃ residence time 12min, second zone 50℃ residence time 15min, third zone 60℃ residence time 6min.

[0043] In S4, the hot stamping process parameters are: stamping temperature 80℃, stamping pressure 0.5MPa, stamping speed 2.2m / min, stamping time 1s, and cooling with 40℃ cold air for 6s after stamping.

[0044] Example 3: An easily separable, environmentally friendly cosmetic packaging bottle based on an integrated composite structure, comprising a three-layer structure integrally molded from the inside out, namely: Substrate layer: ABS resin layer, melt flow rate at 220℃ is 1.6-2.0g / 10min, heat distortion temperature ≥90℃; Hydrolyzable inner wall coating: prepared from antibacterial modified starch, adhesion promoter, hydrophobic modifier, thickener and preservative in a mass ratio of 25:2.5:0.8:0.7:0.3, with a dry film thickness of 0.2-0.3 mm; Hot stamping layer: includes a PET carrier layer, a nickel-free aluminum plating layer and a hot melt adhesive layer that are laminated in sequence, wherein the thickness of the PET carrier layer is 10-15μm; The adhesion promoter is a PU dispersion; the hydrophobic modifier is a long-chain alkyl silane; the thickener is sodium hydroxymethyl cellulose; the preservative is phenoxyethanol; the hot melt adhesive layer is an acrylic resin adhesive layer with a thickness of 3-5 μm; and the nickel-free aluminum plating layer has a thickness of 0.1-0.3 μm.

[0045] The method for preparing the antibacterial modified starch includes the following steps: ① The acetal reaction of hydroxypropyl starch with cinnamaldehyde: Add dimethyl sulfoxide to the reaction vessel, start stirring, slowly add hydroxypropyl starch, heat to 80°C, maintain the temperature and stir until the starch is completely dissolved, and obtain a transparent and viscous starch solution. The temperature inside the reactor was lowered to 50°C, p-toluenesulfonic acid was added, and the mixture was stirred to disperse it evenly. Cinnamaldehyde was slowly added dropwise. After the addition was complete, the temperature was maintained at 50°C, and the reaction was carried out in the dark for 12 hours to obtain cinnamaldehyde starch acetal. After the reaction is complete, anhydrous sodium carbonate is slowly added to the reaction vessel to neutralize the acid in the system until it is neutral. The cinnamaldehyde starch acetal was transferred to a precipitation tank containing ethanol, stirred vigorously to allow precipitation, centrifuged to separate the precipitate, collected and vacuum dried to obtain hydroxypropyl starch-cinnamaldehyde acetal. ②Grafted copolymerization of quaternary ammonium salts: Add N,N-dimethylformamide to the polymerization reactor, start stirring, add hydroxypropyl starch-cinnamaldehyde acetal, heat to 70°C, and stir until completely dissolved; Methacryloxyethyltrimethylammonium chloride and azobisisobutyronitrile were added to a reactor; nitrogen was continuously introduced into the reactor to remove oxygen, and then the inlet and outlet were closed to maintain a slight positive pressure in the system; the reaction was carried out at 70°C under nitrogen protection for 8 hours to obtain a quaternary ammonium salt copolymer. After the reaction was completed, the quaternary ammonium salt copolymer was cooled to room temperature, poured into acetone, and stirred rapidly to precipitate the copolymer. The precipitate was filtered, collected, washed with acetone, and dried under vacuum to obtain the modified starch copolymer, i.e., antibacterial modified starch.

[0046] In ①, the hydroxypropyl molar substitution degree of hydroxypropyl starch must be ≥0.1, that is, an average of 0.1 hydroxypropyl groups are introduced on each unit of glucose residue; the solid content of the starch solution is 10%; the mass of p-toluenesulfonic acid added is 1% of the mass of hydroxypropyl starch; and the mass ratio of hydroxypropyl starch to cinnamaldehyde is 15:5.

[0047] In step ②, the mass ratio of cinnamaldehyde starch acetal to methacryloyloxyethyltrimethylammonium chloride is 70:40; methacryloyloxyethyltrimethylammonium chloride is added in the form of an 80% (w / w) aqueous solution of methacryloyloxyethyltrimethylammonium chloride; the amount of azobisisobutyronitrile added is 0.3% of the total mass of cinnamaldehyde starch acetal and methacryloyloxyethyltrimethylammonium chloride, and it is added in the form of a 10% (w / w) azobisisobutyronitrile N,N-dimethylformamide solution.

[0048] The molding process for easily separable, environmentally friendly cosmetic packaging bottles based on an integrated composite structure includes the following steps: S1. Substrate layer injection molding: ABS resin raw material is added to the injection molding machine, melted, injected, held under pressure, cooled and then demolded to obtain ABS bottle substrate; S2. Substrate pretreatment: The inner wall of the ABS bottle substrate is subjected to plasma treatment and primer treatment, and the outer wall of the ABS bottle substrate is subjected to corona treatment and dust removal treatment. S3. Inner wall coating: Antibacterial modified starch is prepared into starch casting liquid, and the casting liquid is coated onto the inner wall of ABS bottle substrate by dip coating method. After pre-drying and gradient drying, a hydrolyzable inner wall coating is formed. S4. Hot stamping on the outer wall: The environmentally friendly hot stamping foil is laminated to the outer wall of the ABS bottle substrate using a hot stamping process to form an environmentally friendly hot stamping layer. S5. Finished Product Processing: Perform performance testing on the composite molded packaging bottles, remove unqualified products, and then package and store them in the warehouse.

[0049] The injection molding machine parameters of S1 are set as follows: front barrel temperature 200℃, middle barrel temperature 210℃, rear barrel temperature 190℃, mold temperature 50℃, injection pressure 80MPa, holding pressure 40MPa, holding time 20s, and cooling time 20s.

[0050] In step S3, the antibacterial modified starch is made into a hydrolyzable inner wall coating, specifically including the following steps: Take the modified starch copolymer and add it to the mixing tank equipped with a high-speed disperser. Add deionized water, adjust the solid content of the system, and disperse at high speed for 2 hours to form a uniform viscous liquid. Reduce the speed and slowly add p-toluenesulfonate pyridinium salt. Continue stirring for 1 hour to ensure that p-toluenesulfonate pyridinium salt is completely and uniformly dispersed. Add adhesion promoter, hydrophobic modifier, thickener and preservative to obtain starch casting liquid. The starch casting solution was degassed using a centrifugal degassing machine and then transferred to a casting machine. The casting machine was started to coat the starch casting solution onto the inner wall of the ABS bottle substrate, resulting in a hydrolyzable inner wall coating.

[0051] The solid content of the starch casting solution is 40%, and the mass ratio of modified starch copolymer to p-toluenesulfonic acid pyridinium salt is 10:0.6. The dip coating process parameters for S3 are: dip coating speed 4cm / s, residence time 12s; the gradient drying parameters are: first zone 40℃ residence time 12min, second zone 50℃ residence time 15min, third zone 60℃ residence time 6min.

[0052] In S4, the hot stamping process parameters are: stamping temperature 80℃, stamping pressure 0.5MPa, stamping speed 2.2m / min, stamping time 1s, and cooling with 40℃ cold air for 6s after stamping.

[0053] Based on this, the following design was also created: Comparative Example 1: The formulation and experimental method are the same as those in Example 2, but in ①, the mass ratio of hydroxypropyl starch to cinnamaldehyde is 5:5.

[0054] Comparative Example 2: The formulation and experimental method are the same as those in Example 2, but in ①, the mass ratio of hydroxypropyl starch to cinnamaldehyde is 30:5.

[0055] Comparative Example 3: The formulation and experimental method are the same as those in Example 2, but in step ②, the mass ratio of cinnamaldehyde starch acetal to methacryloyloxyethyltrimethylammonium chloride is 70:10.

[0056] Comparative Example 4: The formulation and experimental method are the same as those in Example 2, but in step ②, the mass ratio of cinnamaldehyde starch acetal to methacryloyloxyethyltrimethylammonium chloride is 70:50.

[0057] Comparative Example 5: The formulation and experimental methods were the same as in Example 2, but ordinary starch was used instead of hydroxypropyl starch.

[0058] The antibacterial properties of the product were tested according to GB / T 31402-2015 "Test Method for Antibacterial Properties of Plastic Surfaces"; the water resistance of the product at 25℃ was tested according to ASTM D5946; the adhesion of the inner wall coating of the product was tested according to GB / T 9286-2021 "Cross-cut Test for Paints and Varnishes"; the time required for the coating to completely detach from the substrate was recorded under 65℃ hot water conditions with a full bottle; the cleanliness and color of the ABS bottle flakes after the inner coating was separated and dried were compared with those of the virgin ABS; the corresponding results are summarized and plotted in Table 1: Table 1. Performance test data of environmentally friendly packaging bottles (1) Data analysis shows that: By precisely controlling the degree of reaction between acetalization and graft copolymerization, an "ideal crosslinking network" with both high stability and rapid response was constructed. In Examples 1-3, a balance between crosslinking density and network regularity was achieved by controlling the ratio of hydroxypropyl starch to cinnamaldehyde (mass ratio 12-15:5) and cinnamaldehyde acetal to quaternary ammonium salt monomer (mass ratio 70:30-40). Data show that the three-dimensional network formed under this ratio not only ensures the integrity of the coating (adhesion and water resistance are both optimal at level 0), but also leaves sufficient and uniformly distributed acid-sensitive points (acetal bonds) for subsequent hydrolysis.

[0059] Comparative Example 1 (excessive cinnamaldehyde content) resulted in overly dense crosslinking points and a rigid network. Although it slightly accelerated hydrolysis (28h), the high internal stress of the coating and decreased density led to deterioration in adhesion (Grade 1), water resistance (Grade 1), and antibacterial properties (~96%). Comparative Example 2 (excessively low cinnamaldehyde content) resulted in insufficient crosslinking and a loose network, manifesting as decreased water resistance and adhesion. Furthermore, due to insufficient hydrolyzable bonds, the detachment time was extended to 55h.

[0060] Second, by chemically grafting quaternary ammonium salt functional groups into the network in a covalent manner, efficient and long-lasting antibacterial properties are achieved. At the same time, the degree of introduction of the functional groups directly affects the network structure and separation efficiency. In the examples, an appropriate amount of quaternary ammonium salt monomer (such as the 70:35 ratio in Example 2) provides a near-high antibacterial rate, and the CC bonds formed by its polymerization also serve as additional crosslinking points, further strengthening the network.

[0061] Comparative Example 3 (insufficient quaternary ammonium monomers, 70:10) resulted in a significant decrease in antibacterial performance (~88%). Simultaneously, due to insufficient network cross-linking, its mechanical strength was poor (both water resistance and adhesion were grade 2). Although it detached relatively quickly due to its fragile structure (24h), the peeling was incomplete (residual rate 0.92%). Comparative Example 4 (excessive quaternary ammonium monomers, 70:50) exhibited poor water resistance (grade 2) due to the excessive hydrophilic quaternary ammonium altering the network's hydrophilic-hydrophobic balance. Furthermore, the excessively high cross-linking density hindered water penetration and chain segment movement, making hydrolysis and detachment extremely difficult (60h), resulting in a high residual rate (0.95%). This demonstrates that the dual cross-linking network constructed by the "cinnamaldehyde acetal bridge" and the "quaternary ammonium salt copolymerization point" in this invention is the core element for simultaneously achieving high antibacterial activity and controllable separation.

[0062] Third, using hydroxypropyl starch as the reaction framework and introducing a latent acid agent are prerequisites for ensuring homogeneous film formation, stable adhesion, and hot water-triggered directional hydrolysis separation. The hydroxypropyl starch (MS≥0.1) used in the examples, due to its good solubility and high reactivity, ensured the uniform and sufficient conduct of the acetal reaction and subsequent copolymerization, which is the basis for obtaining Grade 0 adhesion and Grade 0 water resistance. Comparative Example 5 used ordinary starch, which has strong intermolecular hydrogen bonds, few and uneven reaction sites, resulting in insufficient modification and a loose and defective coating structure. Its performance deteriorated: extremely poor antibacterial properties (~76%), extremely poor water resistance and adhesion (Grade 4), and although it detached quickly (12h) due to its fragile structure, the peeling process was disintegration rather than orderly hydrolysis, resulting in a large amount of residue on the ABS substrate (2.35%) and significant discoloration (ΔE2.76), seriously affecting the recycling quality. In contrast, in the embodiment, the uniformly dispersed latent acid agent (pyridinium p-toluenesulfonate) releases H⁺ at specific points in 65°C hot water, attacking the uniformly distributed acetal bonds in the network, causing the entire network to dissociate in an orderly manner "from the inside out," achieving complete and clean stripping within 38-45 hours (residual rate <0.5%, color difference ΔE <1), balancing the stripping efficiency with the cleanliness of the recycled substrate.

[0063] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An easily separable, environmentally friendly cosmetic packaging bottle based on an integrated composite structure, characterized in that: It includes a three-layer structure formed by integrated composite molding from the inside out, namely: Hydrolyzable inner wall coating: prepared from antibacterial modified starch, adhesion promoter, hydrophobic modifier, thickener, preservative and p-toluenesulfonate pyridinium salt, with a dry film thickness of 0.2-0.3 mm; The mass ratio of the antibacterial modified starch, adhesion promoter, hydrophobic modifier, thickener, and preservative is 25-30:1.5-2.5:0.8-1.2:0.3-0.7:0.3-0.7, and the mass ratio of the antibacterial modified starch to p-toluenesulfonic acid pyridinium salt is 10:0.6-0.

8. The adhesion promoter is a PU dispersion; the hydrophobic modifier is a long-chain alkyl silane; the thickener is sodium hydroxymethyl cellulose; and the preservative is phenoxyethanol. Substrate layer: ABS resin layer, with a melt flow rate of 1.6-2.0 g / 10 min at 220℃ and a heat distortion temperature ≥90℃; Hot stamping layer: consists of a PET carrier layer, a nickel-free aluminum plating layer and a hot melt adhesive layer, which are laminated sequentially. The thickness of the PET carrier layer is 10-15μm; the hot melt adhesive layer is an acrylic resin adhesive layer with a thickness of 3-5μm; and the thickness of the nickel-free aluminum plating layer is 0.1-0.3μm. The method for preparing the antibacterial modified starch includes the following steps: ① The acetal reaction of hydroxypropyl starch with cinnamaldehyde: Add dimethyl sulfoxide to the reaction vessel, start stirring, slowly add hydroxypropyl starch, heat to 80°C, maintain the temperature and stir until the starch is completely dissolved to obtain a starch solution; The temperature inside the reactor was lowered to 50°C, p-toluenesulfonic acid was added, and the mixture was stirred to disperse it evenly. Cinnamaldehyde was slowly added dropwise. After the addition was complete, the temperature was maintained at 50°C, and the reaction was carried out in the dark for 12 hours to obtain cinnamaldehyde starch acetal. After the reaction is complete, anhydrous sodium carbonate is slowly added to the reaction vessel to neutralize the acid in the system until it is neutral. The cinnamaldehyde starch acetal was transferred to a precipitation tank containing ethanol, stirred vigorously to precipitate, centrifuged, collected, and vacuum dried to obtain hydroxypropyl starch-cinnamaldehyde acetal. ②Grafted copolymerization of quaternary ammonium salts: Add N,N-dimethylformamide to the polymerization reactor, start stirring, add hydroxypropyl starch-cinnamaldehyde acetal, heat to 70°C, and stir until completely dissolved; Methacryloxyethyltrimethylammonium chloride and azobisisobutyronitrile were added to a reactor; nitrogen was continuously introduced into the reactor to remove oxygen, and then the inlet and outlet were closed to maintain a slight positive pressure in the system; the reaction was carried out at 70°C under nitrogen protection for 8 hours to obtain a quaternary ammonium salt copolymer. After the reaction was completed, the quaternary ammonium salt copolymer was cooled to room temperature, poured into acetone, and stirred rapidly to precipitate the copolymer. The precipitate was filtered, collected, washed with acetone, and dried under vacuum to obtain antibacterial modified starch. In step ①, the hydroxypropyl starch has a hydroxypropyl molar substitution degree ≥ 0.1; the solid content of the starch solution is 10%; the mass of p-toluenesulfonic acid added is 1%-2% of the mass of hydroxypropyl starch; and the mass ratio of hydroxypropyl starch to cinnamaldehyde is 12-15:

5. In step ②, the mass ratio of hydroxypropyl starch-cinnamaldehyde acetal to methacryloyloxyethyltrimethylammonium chloride is 70:30-40; methacryloyloxyethyltrimethylammonium chloride is added in the form of an 80% (w / w) aqueous solution of methacryloyloxyethyltrimethylammonium chloride; the amount of azobisisobutyronitrile added is 0.3% of the total mass of hydroxypropyl starch-cinnamaldehyde acetal and methacryloyloxyethyltrimethylammonium chloride, and it is added in the form of a 10% (w / w) N,N-dimethylformamide solution of azobisisobutyronitrile.

2. A molding process for an easily separable, environmentally friendly cosmetic packaging bottle based on an integrated composite structure as described in claim 1, characterized in that, Includes the following steps: S1. Substrate layer injection molding: ABS resin raw material is added to the injection molding machine, melted, injected, held under pressure, cooled and then demolded to obtain ABS bottle substrate; S2. Substrate pretreatment: The inner wall of the ABS bottle substrate is subjected to plasma treatment and primer treatment, and the outer wall of the ABS bottle substrate is subjected to corona treatment and dust removal treatment. S3. Inner wall coating: Prepare starch casting solution, and apply starch casting solution to the inner wall of ABS bottle substrate by dip coating method. After pre-drying and gradient drying, a hydrolyzable inner wall coating is formed. S4. Hot stamping on the outer wall: The environmentally friendly hot stamping foil is laminated to the outer wall of the ABS bottle substrate using a hot stamping process to form an environmentally friendly hot stamping layer. S5. Finished Product Processing: Perform performance testing on the composite molded packaging bottles, remove unqualified products, and then package and store them in the warehouse.

3. The molding process for the easily separable environmentally friendly cosmetic packaging bottle based on an integrated composite structure according to claim 2, characterized in that, The injection molding machine parameters for step S1 are set as follows: barrel front temperature 200-210℃, middle temperature 210-220℃, rear temperature 190-200℃, mold temperature 50-60℃, injection pressure 80-100MPa, holding pressure 40-60MPa, holding time 15-20s, and cooling time 20-25s.

4. The molding process for the easily separable environmentally friendly cosmetic packaging bottle based on an integrated composite structure according to claim 2, characterized in that, In step S3, the preparation process of the starch casting solution specifically includes the following steps: Take antibacterial modified starch and add it to a mixing tank equipped with a high-speed disperser. Add deionized water and adjust the solid content of the system. Disperse at high speed for 2-2.5 hours to form a uniform viscous liquid. Reduce the speed and slowly add p-toluenesulfonate pyridinium salt. Continue stirring for 1 hour to ensure that p-toluenesulfonate pyridinium salt is completely and uniformly dispersed. Add adhesion promoter, hydrophobic modifier, thickener and preservative. After degassing using a centrifugal degassing machine, obtain the starch casting solution.

5. The molding process for the easily separable environmentally friendly cosmetic packaging bottle based on an integrated composite structure according to claim 4, characterized in that, The solid content of the starch casting solution is 40%.

6. The molding process for the easily separable environmentally friendly cosmetic packaging bottle based on an integrated composite structure according to claim 2, characterized in that, The dip coating process parameters for step S3 are: dip coating speed 4-6 cm / s, residence time 8-12 s; the gradient drying parameters are: first zone 40℃ residence time 12-18 min, second zone 50℃ residence time 10-15 min, third zone 60℃ residence time 6-10 min.

7. The molding process for the easily separable environmentally friendly cosmetic packaging bottle based on an integrated composite structure according to claim 2, characterized in that, In step S4, after the hot foil stamping process, the product is cooled with 40°C cold air for 4-6 seconds.

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