High temperature and pressure resistant modified polypropylene resin, preparation and vaccine bottle processed therewith

Abstract

The application relates to the technical field of medical packaging materials, and particularly discloses a high-temperature and high-pressure resistant modified polypropylene resin, a preparation method thereof and a vaccine bottle processed by using the same. The high-temperature and high-pressure resistant modified polypropylene resin is mainly made of the following raw materials: polypropylene resin, hydrogenated styrene-butadiene-styrene block copolymer, modified nano montmorillonite, organic phosphate nucleating agent, calcium stearate, hindered phenolic antioxidant and phosphite antioxidant. The modified nano montmorillonite is obtained by treating nano montmorillonite with 3-(methacryloyloxy)propyl trimethoxysilane, maleic anhydride, glycidyl methacrylate and dodecafluoroheptyl methacrylate. The modified polypropylene resin has the characteristics of high tensile strength, high impact strength, high heat resistance and high barrier property, can meet the high-temperature sterilization requirement of 121 DEG C for 30 min, and the vaccine bottle does not soften, deform or collapse during high-temperature sterilization, and the sealing integrity is maintained.

Description

Technical Field

[0001] This application relates to the field of medical packaging materials technology, and more specifically, it relates to a high-temperature and high-pressure resistant modified polypropylene resin, the preparation of such resin, and vaccine vials processed therefrom. Background Technology

[0002] Polypropylene resin, due to its good chemical stability, non-toxicity, and ease of processing and molding, has become one of the most important basic materials in the medical packaging field, widely used in the manufacture of medical devices such as infusion bottles, syringes, and vaccine vials. For vaccine vials, after filling, they need to undergo high-temperature sterilization at 121°C for 30 minutes. At this time, polypropylene resin needs to have a high heat distortion temperature to ensure that the vaccine vial does not decompose, soften, or deform under high-temperature sterilization, does not contaminate the contents, and maintains its seal integrity. However, the heat distortion temperature of existing polypropylene resins or modified polypropylene resins is often below 110°C, resulting in insufficient heat resistance, tensile strength often below 20 MPa, and slightly inferior mechanical properties. Therefore, developing a modified polypropylene resin with high heat resistance and high mechanical properties is of great significance for improving the quality of vaccine vials and meeting the requirements of high-temperature sterilization. Summary of the Invention

[0003] In order to improve the heat distortion temperature and tensile strength of modified polypropylene resin, this application provides a high-temperature and high-pressure resistant modified polypropylene resin, its preparation, and a vaccine vial processed therefrom.

[0004] In a first aspect, this application provides a high-temperature and high-pressure resistant modified polypropylene resin, employing the following technical solution: The high-temperature and high-pressure resistant modified polypropylene resin is mainly composed of the following raw materials in parts by weight: 80-90 parts polypropylene resin, 5-13 parts hydrogenated styrene-butadiene-styrene block copolymer, 4-6 parts modified nano-montmorillonite, 0.1-0.5 parts organophosphate nucleating agent, 0.2-0.6 parts calcium stearate, 0.05-0.25 parts hindered phenolic antioxidant, and 0.05-0.25 parts phosphite antioxidant; the modified nano-montmorillonite is obtained by treating nano-montmorillonite with 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate.

[0005] The high-temperature and high-pressure modified polypropylene resin of this application, through the synergistic effect between raw materials, achieves a tensile strength >35MPa and a notched impact strength >8kJ / m. 2 Heat distortion temperature > 125℃, oxygen permeability < 240cm³ 3 / (m 2It exhibits high tensile strength, high impact strength, high heat resistance and high barrier properties (24h·0.1MPa), meets the high temperature sterilization requirements of 121℃ for 30min, and does not decompose, soften, deform or collapse during high temperature sterilization, does not contaminate the contents and maintains the integrity of the seal.

[0006] The high-temperature and high-pressure modified polypropylene resin of this application uses polypropylene resin as the matrix. Hydrogenated styrene-butadiene-styrene block copolymer is added to improve low-temperature toughness. Calcium stearate, hindered phenolic antioxidants, and phosphite antioxidants are also added to ensure processing stability and long-term thermo-oxidative aging stability. An organophosphate nucleating agent is also added, which can improve crystallization temperature, crystallization rate, crystallinity, and crystallization uniformity, resulting in finer grains, a more regular structure, and reduced crystallization defects, thus improving mechanical properties, heat resistance, and barrier properties. Modified nano-montmorillonite is also added, and maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate are grafted onto the nano-montmorillonite to form an organic polymer layer of moderate thickness, stable structure, and synergistic function. It not only forms a layered barrier network, reducing oxygen permeation pathways, but also effectively transfers stress. At the same time, it can effectively improve compatibility and dispersion uniformity, enhance interfacial bonding, reduce interfacial defects, and form covalent bonds at the interface to build a cross-linked network structure, strengthen chemical bonding, increase cross-linking density, enhance overall integrity and network structure stability, reduce network structure defects, and improve mechanical properties and barrier properties, enabling modified polypropylene resin to exhibit superior comprehensive performance.

[0007] Optionally, the modified nano-montmorillonite is prepared using the following method: S1. Mix ethanol aqueous solution and nano-montmorillonite, adjust the pH value to 4-5, heat to 50-70℃, add 3-(methacryloyloxy)propyltrimethoxysilane, stir for 4-6 hours, filter, wash, and dry to obtain silane-grafted nano-montmorillonite. S2. Mix N,N-dimethylformamide and silane-grafted nano-montmorillonite, add maleic anhydride, glycidyl methacrylate and dodecafluoroheptyl methacrylate, stir for 1-3 hours, heat to 70-90℃, add initiator, stir for 7-9 hours, filter, wash and dry to obtain modified nano-montmorillonite.

[0008] Optionally, the weight ratio of the nano-montmorillonite, 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate is 10:(2-4):(0.5-1.5):(1.5-2.5):(0.5-1.5).

[0009] By employing the above technical solution, 3-(methacryloyloxy)propyltrimethoxysilane is first grafted onto nano-montmorillonite using siloxy groups, introducing carbon-carbon unsaturated bonds. Then, under the action of an initiator, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate are grafted onto the nano-montmorillonite through in-situ polymerization to obtain modified nano-montmorillonite. The preparation method of this application adopts a two-step approach, ensuring effective anchoring of the silane coupling agent, efficient copolymerization and grafting of the three functional monomers, and the formation of an organic polymer layer on the surface of the nano-montmorillonite. This significantly improves the performance of the modified nano-montmorillonite and endows the modified polypropylene resin with excellent mechanical properties and barrier properties.

[0010] Optionally, the weight ratio of the nano-montmorillonite to the initiator is 10:(0.5-0.7).

[0011] By adopting the above technical solution and optimizing the amount of initiator, not only can the copolymerization reaction be effectively initiated, but also a suitable grafting rate and graft chain structure can be obtained. This avoids the situation where the side reactions increase or the modification effect decreases due to too much or too little initiator, and ensures the quality stability and consistency of modified nano-montmorillonite.

[0012] Optionally, the initiator is selected from one or more combinations of benzoyl peroxide, azobisisobutyronitrile, dilauryl peroxide, and tert-butyl peroxide.

[0013] Optionally, in step S1, the weight ratio of the nano-montmorillonite and the ethanol aqueous solution is 1:(15-25), and the mass concentration of the ethanol aqueous solution is 40-80%.

[0014] In several implementation schemes, the weight ratio of nano-montmorillonite to ethanol aqueous solution is 1:10. It can also be set to 1:15, 1:16, 1:17, 1:18, 1:19, 1:21, 1:22, 1:23, 1:24, 1:25, etc., as needed, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0015] In several implementations, the mass concentration of the ethanol aqueous solution is 60%, but it can also be set to 40%, 50%, 70%, 80%, etc. as needed, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0016] Optionally, in step S1, the solution used to adjust the pH value is an aqueous hydrochloric acid solution with a mass concentration of 10-30%.

[0017] In several implementations, the mass concentration of the hydrochloric acid aqueous solution is 20%, but it can also be set to 10%, 30%, etc. as needed, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0018] Optionally, in step S2, the weight ratio of the nano-montmorillonite and N,N-dimethylformamide is 1:(15-25).

[0019] In several implementations, the weight ratio of nano-montmorillonite to N,N-dimethylformamide is 1:10. However, the weight ratio can also be set to 1:15, 1:16, 1:17, 1:18, 1:19, 1:21, 1:22, 1:23, 1:24, 1:25, etc., as needed. But it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0020] Optionally, the average sheet thickness of the nano-montmorillonite is ≤25nm, and the average sheet diameter is 50-200nm.

[0021] By adopting the above technical solution, the average sheet thickness and average sheet diameter of nano-montmorillonite are optimized, ensuring the stability of the nano-montmorillonite source. This is also beneficial for the subsequent modification treatment of nano-montmorillonite and its dispersion in polypropylene resin, and improves the tensile strength, impact strength and barrier properties of the modified polypropylene resin, thus improving the overall performance of the modified polypropylene resin.

[0022] Optionally, the organophosphate nucleating agent is selected from one or more combinations of nucleating agent NA-11, nucleating agent NA-21, nucleating agent HPN-68, and nucleating agent NP-509.

[0023] By adopting the above technical solution, the organophosphate nucleating agent is optimized, which facilitates the selection of organophosphate nucleating agents. Moreover, organophosphate nucleating agents can induce polypropylene resin to form fine and regular crystals, increase crystallization temperature, crystallization rate and crystallinity, which is beneficial to improving the mechanical properties, heat resistance and barrier properties of modified polypropylene resin.

[0024] Optionally, the hindered phenolic antioxidant is selected from one or more combinations of antioxidant 1010, antioxidant 1076, and antioxidant 1790.

[0025] Optionally, the phosphite antioxidant is selected from one or more combinations of antioxidant 168, antioxidant 626, and antioxidant TNPP.

[0026] By adopting the above technical solutions, hindered phenolic antioxidants and phosphite antioxidants are optimized, facilitating their selection. Furthermore, the synergistic effect between hindered phenolic and phosphite antioxidants enhances antioxidant properties, prevents high-temperature thermal degradation and discoloration during processing, and ensures the stability of the modified polypropylene resin's performance.

[0027] Secondly, this application provides a method for preparing the aforementioned high-temperature and high-pressure modified polypropylene resin, employing the following technical solution: A method for preparing the high-temperature and high-pressure resistant modified polypropylene resin involves mixing polypropylene resin, hydrogenated styrene-butadiene-styrene block copolymer, modified nano-montmorillonite, organophosphate, calcium stearate, hindered phenolic antioxidant, and phosphite antioxidant, followed by melt extrusion, cooling, and granulation to obtain the modified polypropylene resin.

[0028] By adopting the above technical solution, the raw materials are mixed, melt-extruded, cooled and granulated. The steps are simple, highly operable, and convenient for the preparation of modified polypropylene resin, making it suitable for large-scale industrial mass production.

[0029] Optionally, the melt extrusion temperature is divided into six zones, with the temperatures of zones one through six being 170℃, 180℃, 190℃, 200℃, 205℃, and 210℃, respectively.

[0030] Thirdly, this application provides a vaccine vial, which adopts the following technical solution: A vaccine vial includes a vial body and a vial cap, wherein the vial body is made of the aforementioned high-temperature and high-pressure modified polypropylene resin.

[0031] Optionally, the bottom of the bottle is concave and forms a rounded bottom.

[0032] Optionally, the thickness of the bottle bottom is 2-3mm.

[0033] In summary, this application has at least the following beneficial effects: 1. The high-temperature and high-pressure modified polypropylene resin of this application, through the synergistic effect of the raw materials, possesses high tensile strength, high impact strength, and high heat resistance, meeting the requirements for high-temperature sterilization at 121℃ for 30 minutes. Furthermore, during high-temperature sterilization, the vaccine vials do not soften, deform, or collapse, maintaining their seal integrity. Moreover, it also exhibits high barrier properties, effectively blocking oxygen and delaying vaccine oxidation and deterioration.

[0034] 2. The high-temperature and high-pressure modified polypropylene resin of this application uses polypropylene resin as the matrix. Based on this, an organophosphate nucleating agent is added, which can improve the crystallization temperature, crystallization rate, crystallinity, and crystallization uniformity, resulting in finer grains and a more regular structure. Modified nano-montmorillonite is also added, forming a moderately thick, structurally stable, and functionally synergistic organic polymer layer on the surface of the nano-montmorillonite. This not only forms a layered barrier network but also effectively transfers stress, enhances interfacial bonding, constructs a cross-linked network structure, strengthens chemical bonds, increases cross-linking density, and improves mechanical properties and barrier properties. Furthermore, the modified polypropylene resin exhibits a tensile strength >35MPa and a notched impact strength >8kJ / m². 2 Heat distortion temperature > 125℃, oxygen permeability < 240cm³ 3 / (m 2 (24h·0.1MPa), exhibiting superior overall performance. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the vaccine vial used in Example 1.

[0036] Explanation of the attached diagram labels: 11. Bottle body; 12. Bottle cap. Detailed Implementation

[0037] The present application will be further described in detail below with reference to the embodiments. These embodiments are for illustrative purposes only and are not limited to the scope of application of the present application. Unless otherwise specified, the raw materials or components used in the present application can be obtained commercially or by conventional methods.

[0038] Preparation Example Preparation Example 1 A modified nano-montmorillonite, prepared by the following method: S1. At a rotation speed of 500 r / min, 10 kg of nano-montmorillonite was added to 200 kg of a 60% (w / w) ethanol aqueous solution and stirred for 30 min. The pH was adjusted to 4.5 using a 20% (w / w) hydrochloric acid aqueous solution. Then, the temperature was raised to 60℃, and 2 kg of 3-(methacryloyloxy)propyltrimethoxysilane was added, and the mixture was stirred for 5 h. Afterward, the mixture was filtered. It was washed twice with a 60% (w / w) ethanol aqueous solution (50 kg of ethanol aqueous solution each time) and once with anhydrous ethanol (50 kg of anhydrous ethanol each time). The mixture was then dried at 80℃ to obtain silane-grafted nano-montmorillonite.

[0039] Among them, the nano-montmorillonite is sodium-based nano-montmorillonite, with an average sheet thickness of 20 nm and an average sheet diameter of 100 nm.

[0040] S2. At a rotation speed of 500 r / min, add the silane-grafted nano-montmorillonite obtained in step S1 to 200 kg of N,N-dimethylformamide and stir for 30 min. Add 1 kg of maleic anhydride, 2 kg of glycidyl methacrylate, and 1 kg of dodecafluoroheptyl methacrylate, and stir for 2 h. Then raise the temperature to 80℃, add 0.6 kg of initiator, and stir for 8 h. Afterward, filter, wash twice with 50 kg of N,N-dimethylformamide each time, and wash twice with 50 kg of anhydrous ethanol each time. Dry at 80℃ to obtain modified nano-montmorillonite.

[0041] The initiator is selected from benzoyl peroxide.

[0042] Preparation Example 2 A modified nano-montmorillonite differs from Preparation Example 1 in that the amounts of 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, dodecafluoroheptyl methacrylate, and initiator are different, and the amounts of 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, dodecafluoroheptyl methacrylate, and initiator added are 1 kg, 0.5 kg, 2.5 kg, 1.5 kg, and 0.5 kg respectively.

[0043] Preparation Example 3 A modified nano-montmorillonite differs from Preparation Example 1 in that the amounts of 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, dodecafluoroheptyl methacrylate, and initiator are different, and the amounts of 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, dodecafluoroheptyl methacrylate, and initiator added are 3 kg, 1.5 kg, 1.5 kg, 0.5 kg, and 0.7 kg, respectively.

[0044] Example

[0045] Table 1. Raw material usage of modified polypropylene resin (unit: kg).

[0046] .

[0047] Example 1 A high-temperature and high-pressure resistant modified polypropylene resin is provided. The raw materials and their proportions are shown in Table 1.

[0048] Among them, the polypropylene resin was selected from Yanshan Petrochemical's metallocene polypropylene MT1002; the hydrogenated styrene-butadiene-styrene block copolymer was selected from Baling Petrochemical's SEBS YH-503T; the organophosphate nucleating agent was selected from nucleating agent NA-11; the hindered phenolic antioxidant was selected from antioxidant 1010; the phosphite antioxidant was selected from antioxidant 168; and the modified nano-montmorillonite was prepared using the method of Preparation Example 1.

[0049] A method for preparing a high-temperature and high-pressure resistant modified polypropylene resin includes the following steps: Hydrogenated styrene-butadiene-styrene block copolymer, modified nano-montmorillonite, organophosphates, calcium stearate, hindered phenolic antioxidants, and phosphite antioxidants were added to polypropylene resin at a rotation speed of 500 r / min, and the mixture was stirred for 10 min. Then, a twin-screw extruder was used for melt extrusion, followed by cooling and granulation to obtain modified polypropylene resin.

[0050] The melt extrusion temperature is divided into six zones, with temperatures of 170℃, 180℃, 190℃, 200℃, 205℃, and 210℃ respectively. The screw speed of the twin-screw extruder is 300 r / min.

[0051] Example 2 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that the raw material ratio of the modified polypropylene resin is different, and the raw material ratio of the modified polypropylene resin is shown in Table 1.

[0052] Example 3 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that the raw material ratio of the modified polypropylene resin is different, and the raw material ratio of the modified polypropylene resin is shown in Table 1.

[0053] Example 4 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that the modified nano-montmorillonite in the raw materials of the modified polypropylene resin comes from a different source, and the modified nano-montmorillonite is prepared using the method of Preparation Example 2.

[0054] Example 5 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that the modified nano-montmorillonite in the raw materials of the modified polypropylene resin comes from a different source, and the modified nano-montmorillonite is prepared using the method of Preparation Example 3.

[0055] Comparative Example Comparative Example 1 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that an equal amount of polypropylene resin is used to replace the organophosphate nucleating agent in the raw materials of the modified polypropylene resin.

[0056] Comparative Example 2 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that an equal amount of nano-montmorillonite is used to replace the modified nano-montmorillonite in the raw materials of the modified polypropylene resin.

[0057] Comparative Example 3 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that, in the preparation method of the modified nano-montmorillonite in the raw materials of the modified polypropylene resin, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate are replaced with an equal amount of 3-(methacryloyloxy)propyltrimethoxysilane.

[0058] Comparative Example 4 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that, in the preparation method of modified nano-montmorillonite in the raw materials of the modified polypropylene resin, maleic anhydride is used to replace glycidyl methacrylate and dodecafluoroheptyl methacrylate in equal amounts.

[0059] Comparative Example 5 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that, in the preparation method of modified nano-montmorillonite in the raw materials of the modified polypropylene resin, maleic anhydride and dodecafluoroheptyl methacrylate are replaced with an equal amount of glycidyl methacrylate.

[0060] Comparative Example 6 A high-temperature and high-pressure resistant modified polypropylene resin differs from Example 1 in that, in the preparation method of modified nano-montmorillonite in the raw materials of the modified polypropylene resin, maleic anhydride and glycidyl methacrylate are replaced with an equal amount of dodecylfluoroheptyl methacrylate.

[0061] Application examples Application Example 1 A type of vaccine vial, as shown in the reference Figure 1 The vaccine vial includes a vial body 11 and a vial cap 12. The bottom of the vial body 11 is concave and forms a rounded bottom. The thickness of the bottom of the vial body 11 is 2.3 mm, and the thickness of the vial body 11 is 1 mm. By making the bottom concave and forming a rounded bottom, and increasing the thickness of the bottom, the high temperature and high pressure resistance of the vaccine vial can be effectively improved.

[0062] The bottle body 11 is made of modified polypropylene resin, which is prepared using the method described in Example 1.

[0063] Application Example 2-5 A vaccine vial differs from Application Example 1 in that the source of the modified polypropylene resin is different, and the modified polypropylene resins of Application Examples 2-5 were prepared sequentially using the methods of Examples 2-5, respectively.

[0064] Comparative application examples Comparative Application Examples 1-6 A vaccine vial differs from Application Example 1 in that the source of the modified polypropylene resin is different, and the modified polypropylene resins of Comparative Application Examples 1-6 were prepared sequentially using the methods of Comparative Examples 1-6.

[0065] Performance testing (1) The modified polypropylene resins obtained in Examples 1-5 were taken as samples respectively, and biosafety and chemical safety tests were conducted on the modified polypropylene resins obtained in Examples 1-5 according to the Pharmacopoeia of the People's Republic of China (2025 edition).

[0066] After testing, the modified polypropylene resins of Examples 1-5 showed no sensitization in skin sensitization tests, no cytotoxicity in cytotoxicity tests, bacterial endotoxin ≤0.25 EU / mL, residue on ignition content ≤0.1%, no detection of heavy metal leaching, and no detection of easily oxidized leaching. The modified polypropylene resins of Examples 1-5 have good safety and biocompatibility and meet the requirements of the pharmacopoeia.

[0067] (2) The modified polypropylene resins obtained in Examples 1-5 and Comparative Examples 1-6 were taken as samples, and the following performance tests were performed on the modified polypropylene resins. The test results are shown in Table 2.

[0068] The tensile strength was tested in accordance with GB / T1040.2-2022 "Determination of tensile properties of plastics - Part 2: Test conditions for molded and extruded plastics".

[0069] According to GB / T1843-2008 "Determination of Impact Strength of Plastic Cantilever Beams", the notched impact strength was tested.

[0070] The heat distortion temperature was tested in accordance with GB / T1634.2-2019 "Determination of heat distortion temperature of plastics - Part 2: Plastics, hard rubber and long fiber reinforced composites".

[0071] According to GB / T19789-2021 "Test Method for Oxygen Permeability of Plastic Films and Sheets for Packaging Materials - Coulometric Test", the oxygen permeability is tested, and the lower the oxygen permeability, the better the barrier properties.

[0072] Table 2 Test Results

[0073] As can be seen from Table 2, the modified polypropylene resin of this application has high tensile strength and notched impact strength, with a tensile strength of 35.4-36.8 MPa and a notched impact strength of 8.2-9.5 kJ / m. 2 It exhibits high tensile strength and high impact strength, resulting in superior mechanical properties. Furthermore, it possesses a high heat distortion temperature and low oxygen permeability, with a heat distortion temperature of 128-134℃ and an oxygen permeability of 213-238 cm⁻¹. 3 / (m 2 The modified polypropylene resin of this application exhibits high heat resistance and high barrier properties (24h, 0.1MPa). Through the synergistic effect of the raw materials, it possesses superior overall performance, meeting the requirements for high-temperature sterilization at 121℃ for 30 minutes.

[0074] Comparative Example 1 and Example 1 were compared. The modified polypropylene resin of Comparative Example 1 did not contain an organophosphate nucleating agent in its raw material; the modified polypropylene resin of Example 1 contained an organophosphate nucleating agent in its raw material. This shows that adding an organophosphate nucleating agent to the raw material is beneficial for improving the mechanical properties, heat resistance, and barrier properties of the modified polypropylene resin. This may be because organophosphate nucleating agents can increase the crystallization temperature and crystallization rate, improve the crystal structure, reduce crystallization defects, and refine the grains, thereby enabling the modified polypropylene resin to exhibit superior overall performance.

[0075] Comparative Example 2 and Example 1 were compared. Nano-montmorillonite was added to the raw material of the modified polypropylene resin in Comparative Example 2; modified nano-montmorillonite was added to the raw material of the modified polypropylene resin in Example 1. It can be seen that modifying nano-montmorillonite improves its performance and enhances the mechanical properties and barrier properties of the modified polypropylene resin.

[0076] Comparative Examples 3-6 and Example 1 are compared. The modified montmorillonite nanomaterials of the modified polypropylene resin in Comparative Example 3 were obtained by treating nano-montmorillonite with 3-(methacryloyloxy)propyltrimethoxysilane; the modified montmorillonite nanomaterials of the modified polypropylene resin in Comparative Example 4 were obtained by treating nano-montmorillonite with 3-(methacryloyloxy)propyltrimethoxysilane and maleic anhydride; the modified montmorillonite nanomaterials of the modified polypropylene resin in Comparative Example 5 were obtained by treating nano-montmorillonite with 3-(methacryloyloxy)propyltrimethoxysilane and glycidyl methacrylate; the modified montmorillonite nanomaterials of the modified polypropylene resin in Comparative Example 6 were obtained by treating nano-montmorillonite with 3-(methacryloyloxy)propyltrimethoxysilane and dodecafluoroheptyl methacrylate; the modified montmorillonite nanomaterials of the modified polypropylene resin in Example 1 were obtained by treating nano-montmorillonite with 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate. This demonstrates that by in-situ polymerization, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate are grafted onto nano-montmorillonite to form a multifunctional synergistic organic polymer layer. This effectively improves compatibility and dispersion uniformity, enhances interfacial bonding, reduces interfacial defects, and forms covalent bonds at the interface to construct a cross-linked network structure. This strengthens chemical bonding, increases cross-linking density, enhances overall integrity and network structure stability, reduces network structure defects, improves tensile strength and notched impact strength, and reduces oxygen permeability, resulting in modified polypropylene resin exhibiting superior comprehensive performance.

[0077] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A high-temperature and high-pressure resistant modified polypropylene resin, characterized in that: It is mainly made from the following raw materials in parts by weight: 80-90 parts of polypropylene resin, 5-13 parts of hydrogenated styrene-butadiene-styrene block copolymer, 4-6 parts of modified nano-montmorillonite, 0.1-0.5 parts of organophosphate nucleating agent, 0.2-0.6 parts of calcium stearate, 0.05-0.25 parts of hindered phenolic antioxidant, and 0.05-0.25 parts of phosphite antioxidant; the modified nano-montmorillonite is obtained by treating nano-montmorillonite with 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate.

2. The high-temperature and high-pressure resistant modified polypropylene resin according to claim 1, characterized in that: The modified nano-montmorillonite was prepared using the following method: S1. Mix ethanol aqueous solution and nano-montmorillonite, adjust the pH value to 4-5, heat to 50-70℃, add 3-(methacryloyloxy)propyltrimethoxysilane, stir for 4-6 hours, filter, wash, and dry to obtain silane-grafted nano-montmorillonite. S2. Mix N,N-dimethylformamide and silane-grafted nano-montmorillonite, add maleic anhydride, glycidyl methacrylate and dodecafluoroheptyl methacrylate, stir for 1-3 hours, heat to 70-90℃, add initiator, stir for 7-9 hours, filter, wash and dry to obtain modified nano-montmorillonite.

3. The high-temperature and high-pressure resistant modified polypropylene resin according to claim 2, characterized in that: The weight ratio of the nano-montmorillonite, 3-(methacryloyloxy)propyltrimethoxysilane, maleic anhydride, glycidyl methacrylate, and dodecafluoroheptyl methacrylate is 10:(2-4):(0.5-1.5):(1.5-2.5):(0.5-1.5).

4. The high-temperature and high-pressure resistant modified polypropylene resin according to claim 2, characterized in that: The weight ratio of the nano-montmorillonite to the initiator is 10:(0.5-0.7).

5. The high-temperature and high-pressure modified polypropylene resin according to claim 1, characterized in that: The average thickness of the nano-montmorillonite sheets is ≤25nm, and the average sheet diameter is 50-200nm.

6. The high-temperature and high-pressure resistant modified polypropylene resin according to claim 1, characterized in that: The organophosphate nucleating agent is selected from one or more combinations of nucleating agent NA-11, nucleating agent NA-21, nucleating agent HPN-68, and nucleating agent NP-509.

7. The high-temperature and high-pressure resistant modified polypropylene resin according to claim 1, characterized in that: The hindered phenolic antioxidant is selected from one or more combinations of antioxidant 1010, antioxidant 1076, and antioxidant 1790.

8. The high-temperature and high-pressure resistant modified polypropylene resin according to claim 1, characterized in that: The phosphite antioxidant is selected from one or more combinations of antioxidant 168, antioxidant 626, and antioxidant TNPP.

9. The method for preparing the high-temperature and high-pressure modified polypropylene resin according to any one of claims 1-8, characterized in that: The process includes the following steps: mixing polypropylene resin, hydrogenated styrene-butadiene-styrene block copolymer, modified nano-montmorillonite, organophosphate, calcium stearate, hindered phenolic antioxidant, and phosphite antioxidant, followed by melt extrusion, cooling, and granulation to obtain modified polypropylene resin.

10. A vaccine vial, characterized in that: It includes a bottle body (11) and a bottle cap (12), wherein the bottle body (11) is made of high temperature and high pressure resistant modified polypropylene resin as described in any one of claims 1-8.

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