Layered barrel body for storing high-purity reagent and preparation process of layered barrel body

Abstract

The invention relates to a layered barrel for storing a high-purity reagent and a preparation process of the layered barrel, and belongs to the technical field of ultra-clean plastic containers. The high-density polyethylene composite material is composed of an outer layer, a middle layer and an inner layer from outside to inside, the outer layer comprises, by mass, 80-90 parts of high-density polyethylene, 3-5 parts of dark blue master batch and 5-8 parts of filler, the middle layer comprises, by mass, 80-90 parts of high-density polyethylene, 3-5 parts of light blue modified color master batch and 3-5 parts of compatilizer, and the inner layer is made of high-density polyethylene; through the design of the three layers, the barrel body has excellent anti-swelling performance, metal ions can be prevented from being separated out, stored high-purity reagents can be prevented from being polluted by impurities, and therefore high cleanliness can be guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of ultra-clean plastic container technology, and relates to a layered container for storing high-purity reagents and its preparation process. Background Technology

[0002] High-purity chemical reagents, such as semiconductor wet electronics chemicals, pure acids, and hydrogen peroxide, are key basic materials in precision manufacturing, analytical testing, and biomedicine. Their purity and stability directly affect the quality and performance of downstream products. Therefore, extremely stringent requirements are placed on packaging containers for storing such reagents, which must possess ultra-low leaching, excellent barrier properties, superior chemical stability, and good mechanical properties.

[0003] Currently, most containers used for storing high-purity reagents on the market are single-layer plastic drums, typically made of high-density polyethylene or polypropylene. While these materials offer advantages such as low cost, good processability, and impact resistance, they still suffer from the following significant technical drawbacks: insufficient barrier properties, swelling resistance, and reagent compatibility issues.

[0004] To improve barrier properties, existing technologies have developed double-layer co-extruded containers, typically with an outer / inner layer structure. The inner layer uses pure resin to ensure compatibility, while the outer layer adds color masterbatch to provide light-blocking properties. However, this structure is merely a simple superposition of functions and fails to fundamentally solve the balance problem between barrier properties and swelling resistance. The outer layer material is still the base resin, offering limited improvement in swelling resistance; the inner layer lacks a dedicated barrier layer, resulting in poor impermeability.

[0005] Therefore, there is an urgent need in this field to develop a new type of packaging container that can ensure ultra-high cleanliness while achieving excellent anti-swelling properties, so as to meet the highest standards of modern industry for the storage of high-purity reagents. Summary of the Invention

[0006] The purpose of this invention is to provide a layered container for storing high-purity reagents and its preparation process, which gives the container excellent anti-swelling properties and can prevent the precipitation of metal ions and impurities from contaminating the stored high-purity reagents, thereby ensuring high cleanliness.

[0007] The objective of this invention can be achieved through the following technical solutions: On one hand, the present invention provides a layered container for storing high-purity reagents, which consists of an outer layer, a middle layer and an inner layer from the outside to the inside. By mass, the outer layer comprises 80-90 parts of high-density polyethylene, 3-5 parts of dark blue masterbatch and 5-8 parts of filler; the middle layer comprises 80-90 parts of high-density polyethylene, 3-5 parts of light blue modified masterbatch and 3-5 parts of compatibilizer; and the inner layer is high-density polyethylene. The filler is montmorillonite treated with UV-326 anti-ultraviolet agent and ethylene-vinyl alcohol copolymer, and the modified masterbatch is plasma fluorinated.

[0008] The barrel prepared by this invention consists of three layers. The outer layer is dark blue, which can effectively absorb and block most ultraviolet and visible light, providing reliable light protection. The middle layer is light blue, which makes it easy to observe the wear and tear on the outer layer. The inner layer is made of pure high-density polyethylene, which eliminates the risk of introducing contaminants from the inner wall of the container and ensures the initial purity of the reagent.

[0009] The outer layer uses UV-326 and ethylene-vinyl alcohol copolymer-modified montmorillonite as filler, mixed with high-density polyethylene. This not only enhances the mechanical strength of the container but also significantly extends the permeation path of gas and solvent molecules due to the structure of montmorillonite. Furthermore, the EVOH-encapsulated montmorillonite bonds better with the matrix, while UV-326 provides the outer layer with long-lasting resistance to UV aging. The middle layer incorporates plasma-fluorinated modified color masterbatch, effectively resisting solvent penetration and corrosion, forming a synergistic physical-chemical barrier with the outer layer. The nanosheet filler of the outer layer and the fluorinated inert surface of the middle layer work together to form a three-dimensional barrier network from macro to micro, exhibiting significantly better resistance to solvent vapor and oxygen permeation than single-layer or ordinary multi-layer containers. This enhances the resistance to swelling and cracking in chemical reagent environments, extending the service life. These treatments further prevent contamination of the internally stored reagents by impurity ions, ensuring the high cleanliness of the layered container, making it suitable for storing high-purity reagents.

[0010] As a preferred embodiment of the present invention, the preparation process of the modified color masterbatch is as follows: By weight, 10-15 parts of color masterbatch are dispersed in 150-200 parts of ethanol aqueous solution, and ultrasonically treated at 500-800W for 30-60 minutes to obtain color masterbatch dispersion. 1-1.5 parts of silane coupling agent KH560 are added, and the mixture is stirred at 60-70℃ and 300-500rpm for 6-12 hours. After stirring, the product is washed by centrifugation with ethanol and deionized water, dried at 80-90℃ for 24-40 hours, and then ball-milled to obtain pretreated color masterbatch. The pretreated color masterbatch is then subjected to plasma fluorination treatment to obtain modified color masterbatch.

[0011] In this invention, the light blue masterbatch in the middle layer material undergoes modification treatment. First, it is treated with KH560 to improve the interfacial bonding force between the masterbatch and the high-density polyethylene matrix, thereby reducing interfacial defects and enhancing the mechanical properties and stability of the composite material. Furthermore, fluorine atoms are introduced onto the surface of the pretreated masterbatch, and a dense fluorinated layer is formed through plasma treatment. This layer possesses extremely high chemical inertness and extremely low surface energy, effectively resisting and blocking the penetration, precipitation, and adsorption of chemical solvents, thus helping to improve the cleanliness of the container environment.

[0012] The masterbatch is first treated with silane to improve its dispersibility and interfacial strength, reducing micropores and defects at the interface. Then, plasma fluorination treatment imparts surface inertness. The combination of these two methods allows the modified masterbatch to be uniformly dispersed in the plastic matrix while actively blocking permeation, thus constructing a dual anti-permeation system. This avoids stress concentration and microcracks caused by interfacial debonding in solvent environments, thereby improving the tank's resistance to environmental stress cracking and preventing deformation or breakage due to swelling.

[0013] By modifying the masterbatch, a physical barrier can be formed, blocking the migration path of metal ions from the masterbatch to external reagents. Therefore, reagent molecules cannot penetrate this inert barrier to reach the internal pigments, thus preventing the dissolution and removal of metal ions. Furthermore, surface fluorination treatment avoids ion exchange or dissolution processes.

[0014] As a preferred embodiment of the present invention, the preparation process of the filler is as follows: A UV-resistant agent solution with a volume ratio of 1:1 was mixed with a montmorillonite suspension and stirred at 70°C and 500 rpm for 20-25 hours. After centrifugation, washing, drying at 60°C for 48 hours, and ball milling through a 300-mesh sieve, pretreated montmorillonite was obtained. Ethylene-vinyl alcohol copolymer particles were dried in a vacuum oven at 90°C for 8 hours. The dried ethylene-vinyl alcohol copolymer particles with a mass ratio of 90:(5-10) were premixed with the pretreated montmorillonite in a high-speed mixer for 5 minutes. After melt blending at 200-215°C and granulation, the filler was obtained.

[0015] During the preparation of the filler, montmorillonite is first treated with an anti-UV agent. The anti-UV agent molecules organically modify the sodium-based montmorillonite, expanding its interlayer spacing. The adsorption of the montmorillonite into the modified interlayer via van der Waals forces and hydrogen bonds facilitates subsequent insertion of the ethylene-vinyl alcohol copolymer. This results in a composite filler that improves compatibility with EVOH and provides UV protection, enhancing barrier properties and mechanical performance. Furthermore, encapsulating the montmorillonite filler with EVOH prevents impurities from contacting the contents. The addition of the anti-UV agent prevents photo-oxidative degradation of the outer high-density polyethylene layer under UV irradiation, avoiding damage to the tank's structural integrity and reducing pathways for metal ion migration.

[0016] As a preferred embodiment of the present invention, the mass ratio of the outer layer, the middle layer and the inner layer is 1:(2~4):1.

[0017] As a preferred embodiment of the present invention, the compatibilizer is at least one of maleic anhydride-grafted polyethylene, maleic anhydride-grafted ethylene-vinyl acetate, and polyamide.

[0018] Compatibilizers reduce interfacial tension, promoting the wetting and dispersion of the middle layer components in the HDPE matrix, maximizing their anti-permeability and barrier effects, and avoiding performance defects caused by agglomeration.

[0019] As a preferred embodiment of the present invention, the gas introduced during plasma treatment is carbon tetrafluoride and argon in a volume ratio of (1~3):1, and the treatment is carried out for 13~35 minutes at a frequency of 13.56 MHz and a power of 50~100 W.

[0020] As a preferred technical solution of the present invention, the montmorillonite suspension is: a montmorillonite suspension with a mass fraction of 6~10% obtained by mixing sodium-based montmorillonite with deionized water and ultrasonically treating it at 600W and 60℃ for 30min.

[0021] As a preferred technical solution of the present invention, the anti-ultraviolet solution is prepared by stirring UV-326 anti-ultraviolet agent with anhydrous ethanol at 50°C until completely dissolved to obtain an anti-ultraviolet agent solution with a concentration of 5~7%.

[0022] This invention uses UV-326 because this reagent has polar functional groups, readily interacts with montmorillonite, and has high thermal stability and resistance to processing temperatures.

[0023] A process for preparing a layered container for storing high-purity reagents includes the following steps: S1. After the three layers of raw materials are mixed evenly and dried, they are fed into the three different screw extruders of the three-layer co-extrusion blow molding machine. S2. High-purity nitrogen is used to blow the molten raw material in the extruder to form a multi-layer barrel blank. The temperature of each screw extruder is 180~230℃ for the outer layer, 190~235℃ for the middle layer, and 200~250℃ for the inner layer. The blowing ratio is 2.7~3.3 and the traction speed is 6~8m / min.

[0024] S3. In a Class 1000 clean environment, water is introduced to cool and solidify the multi-layer barrel blank, and then purged with high-purity nitrogen gas to obtain the layered barrel body used for storing high-purity reagents.

[0025] As a preferred embodiment of the present invention, the flow rate of the high-purity nitrogen gas is 35~55 m³ / h. 3In step S3, the cooling time is 150-210 seconds, and the water flow rate is 15-20 m³ / h. 3 / h.

[0026] This invention utilizes a three-layer co-extrusion, high-purity nitrogen blow molding technology, with the inner layer having the highest temperature (200~250℃). This ensures full plasticization of HDPE, resulting in a more densely packed molecular chain arrangement and an extremely smooth inner wall, thereby reducing the surface area and adsorption points in contact with chemical solvents from the source. The gradient temperature setting of the three layers enables simultaneous extrusion of the three layers, avoiding interlayer interference.

[0027] The beneficial effects of this invention are: This invention provides a layered container for storing high-purity reagents. The container consists of three layers. The outer layer is dark blue, made from dark blue masterbatch, montmorillonite treated with UV-326 anti-ultraviolet agent and ethylene-vinyl alcohol copolymer, and high-density polyethylene. This ensures the mechanical strength of the layered container. Furthermore, the addition of modified montmorillonite extends the permeation path of gas and solvent molecules, and the anti-ultraviolet agent also improves the anti-aging ability of the outer layer, extending its service life. The middle layer is prepared from modified light blue masterbatch, high-density polyethylene, and a compatibilizer. The masterbatch, pretreated with a silane coupling agent, is modified by plasma. This modification improves the interfacial bonding between the masterbatch and the high-density polyethylene matrix through the compatibilizer, reducing interfacial defects. Additionally, plasma fluorination effectively resists and blocks the penetration and adsorption of chemical solvents, improving the container's impermeability. The inner layer is made of high-density polyethylene, ensuring the high cleanliness of the container. Through the design of the above three layers, the container has excellent anti-permeability and anti-swelling properties, which can prevent metal ions from leaching out and contaminating the stored high-purity reagents, thus ensuring the high cleanliness of the container. Detailed Implementation

[0028] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with embodiments, is provided below.

[0029] The high-density polyethylene is Qatar TR571, and the ethylene-vinyl alcohol copolymer was purchased from Dongguan Jinshixiang Plastic Raw Materials Co., Ltd., with the grade SP441B. The main components of the masterbatch used are: 65% pigment, 12% linear low-density polyethylene (ExxonMobil LL6201), 20% low-density polyethylene (Qatar Petrochemical MG70), and 3% silicone masterbatch (Dow Corning MB50-002).

[0030] Example 1 Outer layer: 80 parts high-density polyethylene, 3 parts dark blue masterbatch and 5 parts filler; Middle layer: 80 parts high-density polyethylene, 3 parts light blue modified masterbatch and 3 parts maleic anhydride grafted polyethylene; Inner layer is high-density polyethylene, and the mass ratio of the outer layer, middle layer and inner layer is 1:2:1.

[0031] Preparation of modified masterbatch: By weight, 10 parts of masterbatch were dispersed in 150 parts of an ethanol-water solution with a volume ratio of 1:10. The mixture was ultrasonically treated at 500W for 30 minutes to obtain a masterbatch dispersion. One part of silane coupling agent KH560 was added, and the mixture was stirred at 60℃ and 300rpm for 6 hours. After stirring, the product was washed by centrifugation with ethanol and deionized water, dried at 80℃ for 24 hours, and then ball-milled to obtain pretreated masterbatch. The pretreated masterbatch was then subjected to plasma fluorination treatment to obtain modified masterbatch. The gas introduced was carbon tetrafluoride and argon with a volume ratio of 1:1, and the treatment was carried out at a frequency of 13.56 MHz and a power of 50W for 13 minutes.

[0032] Preparation of filler: Sodium-based montmorillonite was mixed with deionized water and ultrasonically treated at 600W and 60℃ for 30 min to obtain a montmorillonite suspension with a mass fraction of 6%. UV-326 anti-ultraviolet agent was stirred with anhydrous ethanol at 50℃ until completely dissolved to obtain an anti-ultraviolet agent solution with a concentration of 5%.

[0033] A UV-resistant agent solution with a volume ratio of 1:1 was mixed with a montmorillonite suspension and stirred at 70°C and 500 rpm for 20 h. After centrifugation, washing, drying at 60°C for 48 h, and ball milling through a 300-mesh sieve, pretreated montmorillonite was obtained. Ethylene-vinyl alcohol copolymer particles were dried in a vacuum oven at 90°C for 8 h. The dried ethylene-vinyl alcohol copolymer particles with a mass ratio of 90:5 were premixed with the pretreated montmorillonite in a high-speed mixer for 5 min. After melt blending at 200°C and granulation, the filler was obtained.

[0034] S1. After the three layers of raw materials are mixed evenly and dried, they are fed into the three different screw extruders of the three-layer co-extrusion blow molding machine. S2. High-purity nitrogen is used to blow the molten raw material in the extruder to form a multi-layer barrel blank. The temperature of each screw extruder is 180℃ for the outer layer, 190℃ for the middle layer, and 200℃ for the inner layer. The blowing ratio is 2.7 and the traction speed is 6m / min.

[0035] S3. In a Class 1000 cleanroom environment, the flow rate is 15m³ / h. 3 The multi-layered barrel blank is cooled by water at a flow rate of 35 m³ / h for 150 seconds, solidified, and then purged with high-purity nitrogen gas to obtain the layered barrel body used for storing high-purity reagents. 3 / h.

[0036] Example 2 Outer layer: 85 parts high-density polyethylene, 4 parts dark blue masterbatch and 6 parts filler; Middle layer: 85 parts high-density polyethylene, 4 parts light blue modified masterbatch and 4 parts maleic anhydride grafted polyethylene; Inner layer is high-density polyethylene, and the mass ratio of the outer layer, middle layer and inner layer is 1:3:1.

[0037] Preparation of modified masterbatch: By weight, 13 parts of masterbatch were dispersed in 170 parts of an ethanol-water solution with a volume ratio of 1:10. The solution was ultrasonically treated at 600W for 35 minutes to obtain a masterbatch dispersion. 1.3 parts of silane coupling agent KH560 were added, and the mixture was stirred at 65℃ and 400rpm for 10 hours. After stirring, the product was washed by centrifugation with ethanol and deionized water, dried at 85℃ for 30 hours, and then ball-milled to obtain pretreated masterbatch. The pretreated masterbatch was then subjected to plasma fluorination treatment to obtain modified masterbatch. The gas introduced was carbon tetrafluoride and argon with a volume ratio of 2:1, and the treatment was carried out at a frequency of 13.56 MHz and a power of 80W for 25 minutes.

[0038] Preparation of filler: Sodium-based montmorillonite was mixed with deionized water and ultrasonically treated at 600W and 60℃ for 30 min to obtain a montmorillonite suspension with a mass fraction of 8%. UV-326 anti-ultraviolet agent was stirred with anhydrous ethanol at 50℃ until completely dissolved to obtain an anti-ultraviolet agent solution with a concentration of 6%.

[0039] A UV-resistant agent solution with a volume ratio of 1:1 was mixed with a montmorillonite suspension and stirred at 70°C and 500 rpm for 22 hours. After centrifugation, washing, drying at 60°C for 48 hours, and ball milling through a 300-mesh sieve, pretreated montmorillonite was obtained. Ethylene-vinyl alcohol copolymer particles were dried in a vacuum oven at 90°C for 8 hours. The dried ethylene-vinyl alcohol copolymer particles with a mass ratio of 90:7 were premixed with the pretreated montmorillonite in a high-speed mixer for 5 minutes. After melt blending at 205°C and granulation, the filler was obtained.

[0040] S1. After the three layers of raw materials are mixed evenly and dried, they are fed into the three different screw extruders of the three-layer co-extrusion blow molding machine. S2. The molten raw material in the extruder is blown into shape by high-purity nitrogen to obtain a multi-layer barrel blank. The temperature of each screw extruder is 200℃ for the outer layer, 215℃ for the middle layer, and 230℃ for the inner layer. The blow-up ratio is 3 and the traction speed is 7m / min.

[0041] S3. In a Class 1000 cleanroom environment, the flow rate is 17m³ / h. 3 The multi-layered barrel blank is cooled by water at a flow rate of 45 m³ / h for 190 s, solidified, and then purged with high-purity nitrogen gas to obtain the layered barrel body used for storing high-purity reagents.3 / h.

[0042] Example 3 Outer layer: 90 parts high-density polyethylene, 5 parts dark blue masterbatch and 8 parts filler; Middle layer: 90 parts high-density polyethylene, 5 parts light blue modified masterbatch and 5 parts maleic anhydride grafted polyethylene; Inner layer is high-density polyethylene, and the mass ratio of the outer layer, middle layer and inner layer is 1:4:1.

[0043] Preparation of modified masterbatch: By weight, 15 parts of masterbatch were dispersed in 200 parts of an ethanol-water solution with a volume ratio of 1:10. The solution was ultrasonically treated at 800W for 60 minutes to obtain a masterbatch dispersion. 1.5 parts of silane coupling agent KH560 were added, and the mixture was stirred at 70℃ and 500rpm for 12 hours. After stirring, the product was washed with ethanol and deionized water by centrifugation, dried at 90℃ for 40 hours, and then ball-milled to obtain pretreated masterbatch. The pretreated masterbatch was then subjected to plasma fluorination treatment to obtain modified masterbatch. The gas introduced was carbon tetrafluoride and argon with a volume ratio of 3:1, and the treatment was carried out at a frequency of 13.56 MHz and a power of 100W for 35 minutes.

[0044] Preparation of filler: Sodium-based montmorillonite was mixed with deionized water and ultrasonically treated at 600W and 60℃ for 30 minutes to obtain a 10% montmorillonite suspension. UV-326 anti-ultraviolet agent was stirred with anhydrous ethanol at 50℃ until completely dissolved to obtain a 7% anti-ultraviolet agent solution.

[0045] A UV-resistant agent solution with a volume ratio of 1:1 was mixed with a montmorillonite suspension and stirred at 70°C and 500 rpm for 25 h. After centrifugation, washing, drying at 60°C for 48 h, and ball milling through a 300-mesh sieve, pretreated montmorillonite was obtained. Ethylene-vinyl alcohol copolymer particles were dried in a vacuum oven at 90°C for 8 h. The dried ethylene-vinyl alcohol copolymer particles with a mass ratio of 90:10 were premixed with the pretreated montmorillonite in a high-speed mixer for 5 min. After melt blending at 215°C and granulation, the filler was obtained.

[0046] S1. After the three layers of raw materials are mixed evenly and dried, they are fed into the three different screw extruders of the three-layer co-extrusion blow molding machine. S2. High-purity nitrogen is used to blow the molten raw material in the extruder to form a multi-layer barrel blank. The temperature of each screw extruder is 230℃ for the outer layer, 235℃ for the middle layer, and 250℃ for the inner layer. The blowing ratio is 3.3 and the traction speed is 8m / min.

[0047] S3. In a Class 1000 cleanroom environment, the flow rate is 20m³ / h. 3The multi-layered barrel blank is cooled by water at a flow rate of 55 m³ / h for 210 seconds, solidified, and then purged with high-purity nitrogen gas to obtain the layered barrel body used for storing high-purity reagents. 3 / h.

[0048] Comparative Example 1 Comparative Example 1 is basically the same as Example 1, except that the outer filler in this comparative example was not treated with ethylene-vinyl alcohol copolymer.

[0049] Comparative Example 2 Comparative Example 2 is basically the same as Example 1, except that the outer layer filler in this comparative example is untreated montmorillonite.

[0050] Comparative Example 3 Comparative Example 3 is basically the same as Example 1, except that the color masterbatch in this comparative example was not treated with KH560.

[0051] Comparative Example 4 Comparative Example 4 is basically the same as Example 1, except that the color masterbatch in this comparative example was not treated with plasma.

[0052] Comparative Example 5 Comparative Example 5 is basically the same as Example 1, except that the color masterbatch in this comparative example has not undergone any modification treatment.

[0053] Performance testing: 1. Swelling resistance: Sample pieces of a specified size (50mm * 25mm * original wall thickness) were cut from the barrel walls of the barrels obtained in Examples 1-3 and Comparative Examples 1-5. These samples were then immersed in a 31.5% hydrogen peroxide solution at 40°C for 7 days. The swelling resistance was measured by detecting the percentage change in volume of the sample pieces. The results are shown in Table 1. Table 1 Group Volume change percentage / % Example 1 2.4 Example 2 2.1 Example 3 2.6 Comparative Example 1 5.7 Comparative Example 2 8.3 Comparative Example 3 4.9 Comparative Example 4 7.8 Comparative Example 5 8.7 2. The layered barrels prepared in Examples 1-3 were filled with 36% hydrochloric acid by mass, heated to 85°C for 7 days, and then the number of metal ions precipitated in the immersion solution was tested using ICP-MS / MS, referring to Method SEMI F57. The method detection limit (MDL) was 0.01, and the unit was μg / m³. 2 ND indicates not detected, meaning the result is below the detection limit. The results are shown in Table 2 below: Table 2 Test Project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Na 0.356 0.343 0.361 0.481 0.532 0.422 0.463 0.586 Mg 0.321 0.318 0.336 0.424 0.496 0.389 0.447 0.543 Al 0.627 0.617 0.645 0.687 0.708 0.703 0.754 0.897 K 0.365 0.360 0.372 0.399 0.431 0.405 0.458 0.588 Ti 0.621 0.616 0.633 0.649 0.702 0.699 0.738 0.872 V 0.068 0.064 0.079 0.098 0.105 0.099 0.107 0.120 Cr 0.325 0.320 0.331 0.357 0.379 0.366 0.383 0.416 Mn 0.057 0.052 0.060 0.072 0.092 0.065 0.090 0.105 Fe 0.364 0.355 0.371 0.390 0.409 0.380 0.397 0.410 Ni 0.330 0.320 0.336 0.359 0.368 0.349 0.371 0.380 Cu 0.013 0.008 0.016 0.044 0.052 0.019 0.023 0.030 Zn 0.271 0.265 0.275 0.290 0.309 0.292 0.307 0.313 Mo 0.830 0.824 0.840 0.871 0.906 0.862 0.895 0.910 Ag 0.014 0.012 0.016 0.028 0.037 0.030 0.049 0.056 Sr ND ND ND ND ND ND ND ND Zr ND ND ND ND ND ND ND ND Co ND ND ND ND ND ND ND ND Pt ND ND ND ND ND ND ND ND Based on the above data, it can be seen that the barrel has excellent anti-swelling properties, and in Examples 1-3, the number of metal ions precipitated from Al, Fe, Mn, and Zn is ≤1ug / m³. 2 The number of metal ions precipitated by As, Mg, Ti, and V is ≤2 μg / m³.2 The number of metal ions precipitated by Cr, Ni, Ag, and Mo is ≤1 μg / m³. 2 The number of metal ions deposited for Cu, K, Na, Co, Ga, Sr, Zr, and Pt is ≤0.5 ug / m³. 2 Therefore, the layered container prepared by this invention can have excellent cleanliness when storing high-purity reagents.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A layered container for storing high-purity reagents, characterized in that, The material is composed of an outer layer, a middle layer, and an inner layer from the outside in. By mass, the outer layer comprises 80-90 parts high-density polyethylene, 3-5 parts dark blue masterbatch, and 5-8 parts filler; the middle layer comprises 80-90 parts high-density polyethylene, 3-5 parts light blue modified masterbatch, and 3-5 parts compatibilizer; and the inner layer is high-density polyethylene. The filler is montmorillonite treated with UV-326 anti-ultraviolet agent and ethylene-vinyl alcohol copolymer. The modified masterbatch is plasma fluorinated.

2. The layered container for storing high-purity reagents according to claim 1, characterized in that, The preparation process of the modified color masterbatch is as follows: By weight, 10-15 parts of color masterbatch are dispersed in 150-200 parts of ethanol aqueous solution, and ultrasonically treated at 500-800W for 30-60 minutes to obtain color masterbatch dispersion. 1-1.5 parts of silane coupling agent KH560 are added, and the mixture is stirred at 60-70℃ and 300-500rpm for 6-12 hours. After stirring, the product is washed by centrifugation with ethanol and deionized water, dried at 80-90℃ for 24-40 hours, and then ball-milled to obtain pretreated color masterbatch. The pretreated color masterbatch is then subjected to plasma fluorination treatment to obtain modified color masterbatch.

3. The layered container for storing high-purity reagents according to claim 1, characterized in that, The preparation process of the filler is as follows: A UV-resistant agent solution with a volume ratio of 1:1 was mixed with a montmorillonite suspension and stirred at 70°C and 500 rpm for 20-25 hours. After centrifugation, washing, drying at 60°C for 48 hours, and ball milling through a 300-mesh sieve, pretreated montmorillonite was obtained. Ethylene-vinyl alcohol copolymer particles were dried in a vacuum oven at 90°C for 8 hours. The dried ethylene-vinyl alcohol copolymer particles with a mass ratio of 90:(5-10) were premixed with the pretreated montmorillonite in a high-speed mixer for 5 minutes. After melt blending at 200-215°C and granulation, the filler was obtained.

4. The layered container for storing high-purity reagents according to claim 1, characterized in that, The mass ratio of the outer layer, middle layer and inner layer is 1:(2~4):

1.

5. The layered container for storing high-purity reagents according to claim 1, characterized in that, The compatibilizer is at least one of maleic anhydride-grafted polyethylene, maleic anhydride-grafted ethylene-vinyl acetate, and polyamide.

6. The layered container for storing high-purity reagents according to claim 2, characterized in that, The plasma treatment involves introducing carbon tetrafluoride and argon in a volume ratio of (1~3):1, and the treatment is carried out at a frequency of 13.56 MHz and a power of 50~100 W for 13~35 min.

7. The layered container for storing high-purity reagents according to claim 3, characterized in that, The montmorillonite suspension is a montmorillonite suspension with a mass fraction of 6-10% obtained by mixing sodium-based montmorillonite with deionized water and ultrasonically treating it at 600W and 60℃ for 30 minutes.

8. The layered container for storing high-purity reagents according to claim 3, characterized in that, The UV-326 UV-resistant agent solution is prepared by stirring UV-326 UV-resistant agent with anhydrous ethanol at 50°C until completely dissolved to obtain a UV-resistant agent solution with a concentration of 5-7%.

9. A preparation process for a layered container for storing high-purity reagents as described in any one of claims 1-8, characterized in that, Includes the following steps: S1. After the three layers of raw materials are mixed evenly and dried, they are fed into the three different screw extruders of the three-layer co-extrusion blow molding machine. S2. High-purity nitrogen is used to blow the molten raw material in the extruder to form a multi-layer barrel blank. The temperature of each screw extruder is 180~230℃ for the outer layer, 190~235℃ for the middle layer, and 200~250℃ for the inner layer. The blowing ratio is 2.7~3.3 and the traction speed is 6~8m / min. S3. In a Class 1000 clean environment, water is introduced to cool and solidify the multi-layer barrel blank, and then purged with high-purity nitrogen gas to obtain the layered barrel body used for storing high-purity reagents.

10. The preparation process of the layered container for storing high-purity reagents according to claim 9, characterized in that, The flow rate of the high-purity nitrogen gas is 35~55 m³ / h. 3 In step S3, the cooling time is 150-210 seconds, and the water flow rate is 15-20 m³ / h. 3 / h.