Culture bottles and their preparation process

Abstract

This invention belongs to the technical field of polymer compound composition, specifically relating to a culture bottle and its preparation process. The culture bottle comprises the following components by weight: 130 parts polypropylene, 6-10 parts hexagonal boron nitride nanosheets, 3-6.5 parts modifying agent, 6-8 parts P(MPC-co-BMC), 3-8 parts reinforcing agent, 1.5-4 parts compatibilizer, 0.5-1 part antioxidant, and 0.5-0.8 parts lubricant. The preparation process involves blending the components in the culture bottle, followed by plasticizing, injection molding, and blow molding to obtain the culture bottle. This invention, by compounding multiple components such as hexagonal boron nitride nanosheets, modifying agent, and P(MPC-co-BMC) with polypropylene, simultaneously solves the problems of insufficient high-temperature resistance and easy drug adsorption in culture bottles.

Description

Technical Field

[0001] This invention belongs to the field of polymer compound composition technology, specifically relating to a culture bottle and its preparation process. Background Technology

[0002] In bacterial culture, in addition to basic aseptic techniques and culture medium preparation, selecting appropriate culture containers and materials is crucial. Currently, plastic culture bottles, while retaining the advantages of good transparency and controllable pressure resistance of glass culture bottles, further offer the benefits of lower cost, lighter weight, and larger capacity.

[0003] For some drug screening or signaling molecule research experiments, it is necessary to add specific drugs or active small molecules, such as doxorubicin, propofol, verapamil, kinase inhibitors, and certain fluorescent dyes, to the culture medium. However, plastic culture bottles, especially those made of polystyrene or polypropylene, can adsorb some drugs, such as doxorubicin, leading to a decrease in the actual effective drug concentration and affecting the accuracy of experimental results. Furthermore, compared to glass culture bottles, plastic materials have inherently lower high-temperature resistance. Plastic bottles must be sterilized at strictly controlled temperatures; otherwise, the bottles may deform or crack, affecting the sealing effect and sometimes posing a risk of incomplete sterilization, which can affect the accuracy of subsequent experimental data.

[0004] Chinese patent CN109971070A discloses a polypropylene medicine bottle formulation for high-temperature sterilization, which is made from the following raw materials in parts by weight: 80.0~100.0 parts of heat-resistant homopolymer polypropylene resin, 5.0~20.0 parts of impact-resistant copolymer polypropylene resin, 0~10.0 parts of high-density polyethylene resin, 0.5~5.0 parts of color masterbatch, 0.02~1.00 parts of structural stabilizer, 0.2~5.0 parts of maleic anhydride-grafted polypropylene resin, and 0.01~3.00 parts of PXA-LA particles.

[0005] The patent adds PXA-LA particles, which are lignin-acrylic acid polymer complexes. The original design purpose was to adsorb small molecule impurities in polypropylene and prevent dissolution. However, if this formula is used to prepare culture bottles, microporous materials such as PXA-LA particles may adsorb drugs (such as doxorubicin) in the culture medium, resulting in a decrease in the actual drug concentration and affecting the accuracy of experimental data.

[0006] Chinese patent CN113801355A discloses a method for hydrophilic treatment of the surface of a plastic cell culture flask, comprising the following steps: 1) performing a first swelling treatment on the cell culture flask with a first solvent; 2) coating the surface with a first modifier to generate a reactive liquid crystal mixture; 3) removing the first solvent that has penetrated into the surface of the cell culture flask using a solution containing the reactive liquid crystal mixture; 4) performing corona discharge treatment to form a hydrophilic layer on the surface; 5) performing a second swelling treatment on the cell culture flask with a second solvent under pressure; 6) performing a surface modification treatment on the cell culture flask with a solution containing a second modifier; 7) performing a deswelling treatment on the cell culture flask using a vacuum drying method with progressively decreasing negative pressure, followed by washing with water to obtain a cell culture flask with a hydrophilic surface.

[0007] The patented two-step swelling, modification, corona discharge, and deswelling process is cumbersome and requires specific equipment, which is not conducive to large-scale production. In addition, the repeated swelling and shrinkage process will accumulate stress inside the material, which can cause structural changes in the culture bottle. After long-term high-temperature sterilization cycles, it will affect the mechanical strength of the culture bottle. Summary of the Invention

[0008] The purpose of this invention is to provide a culture bottle that simultaneously solves the problems of insufficient high-temperature resistance and easy adsorption of drugs in culture bottles; this invention also provides a preparation process for the culture bottle.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0010] The culture bottle of the present invention comprises, by weight parts, the following components: 130 parts polypropylene, 6-10 parts hexagonal boron nitride nanosheets, 3-6.5 parts modifying agent, 6-8 parts poly(2-methacryloyloxyethylphosphorylcholine-co-butyl methacrylate) (P(MPC-co-BMC)), 3-8 parts reinforcing agent, 1.5-4 parts compatibilizer, 0.5-1 part antioxidant, and 0.5-0.8 parts lubricant.

[0011] in:

[0012] The modified additives include 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 1-naphthyl phosphate monosodium salt monohydrate; by mass parts, 0.8~2.5 parts of 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 2~4 parts of 1-naphthyl phosphate monosodium salt monohydrate.

[0013] The reinforcing agent is cellulose nanocrystals.

[0014] The compatibilizer is hexadecylpyridine chloride or hexadecylpyridine bromide.

[0015] The antioxidant is one of 2,6-di-tert-butyl-p-cresol, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, or 2,2'-methylenebis-(4-methyl-6-tert-butylphenol); the lubricant is one of magnesium stearate, paraffin wax, or polyethylene wax.

[0016] The preparation process of the culture bottle according to the present invention includes the following steps:

[0017] S1. Polypropylene, hexagonal boron nitride nanosheets, modifiers, reinforcing agents, compatibilizers, antioxidants, and lubricants are premixed, and then poly(2-methacryloyloxyethyl phosphorylcholine-co-butyl methacrylate) is added and mixed to obtain a mixture.

[0018] S2. The mixture is plasticized to obtain masterbatch;

[0019] S3. The masterbatch is injection molded to obtain a preform, and the preform is blow molded to obtain a culture bottle.

[0020] in:

[0021] In S1, the premixing speed is 500~600 rpm, the premixing time is 40~80s, and the mixing time is 3~5min.

[0022] In S2, a twin-screw extruder is used for plasticizing. The twin-screw extruder includes six temperature zones: zone 1, zone 2, zone 3, zone 4, zone 5, and zone 6. The temperatures of zones 1, 2, 3, 4, 5, and 6 are set to 175~185℃, 190~200℃, 200~220℃, 220~230℃, 220~230℃, and 210~220℃, respectively. The rotation speed of the twin-screw extruder is 150~200 rpm.

[0023] In S3, an injection molding machine is used for injection molding. The melt temperature of the masterbatch in the injection molding machine is 220~230℃, the injection pressure is 20~30MPa, the mold temperature is 35~65℃, and the holding time is 20~40s.

[0024] In S3, blow molding is performed using a blow molding machine with a blow molding pressure of 0.8~1MPa and a blow molding die temperature of 20~50℃.

[0025] The beneficial effects of this invention are as follows:

[0026] Cellulose nanocrystals, rich in hydroxyl groups, exhibit hydrophilicity. Due to the tendency to minimize surface energy, cellulose nanocrystals adsorb hexagonal boron nitride nanosheets (h-BN nanosheets). The pyridine groups of hexadecylpyridine chloride / bromide further adsorb onto the negatively charged surfaces of the cellulose nanocrystals (CNC, rich in carboxyl / hydroxyl groups) and hexagonal boron nitride nanosheets (h-BN, negatively charged at edge defects) via electrostatic interactions. The alkyl segments of hexadecylpyridine chloride / bromide coat the cellulose nanocrystals and h-BN nanosheets, forming a dispersed configuration. This dispersed configuration prevents the h-BN nanosheets from forming a stacked structure during high-speed shearing, thus avoiding an impact on their specific surface area.

[0027] In the modified additives, the thionyl group (C=S) in the trisodium trithione salt of 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione forms a multi-level coordination relationship with the phosphate group in the monosodium hydrate of 1-naphthyl phosphate. Due to the molecular characteristics of the two modified additives, they tend to form a stable planar configuration. At this time, the rigid aromatic rings (naphthalene ring and triazine ring) in the modified additives can fully form π-π stacking interactions with the six-membered boron nitrogen ring of h-BN nanosheets and anchor them on the surface of h-BN nanosheets. This allows the dispersed configuration and the modified additives to form heterogeneous nucleation regions, regulate and reduce the activation energy barrier of polypropylene segment adsorption, and induce molten polypropylene nucleation by orientation, effectively improving the heat distortion temperature and toughness of the prepared culture bottles in high-temperature environments.

[0028] Since P(MPC-co-BMC) is an amphiphilic block copolymer, it can freely interpenetrate between the dispersed configuration and the polypropylene matrix. On the one hand, it initially reduces the slip resistance between polypropylene chains and the dispersed configuration, promoting the dispersion of the dispersed configuration in the polypropylene matrix. Conversely, P(MPC-co-BMC) can also use the dispersed configuration as an anchor point. The hydrophobic chain ends in P(MPC-co-BMC) are entangled with the chlorinated / brominated hexadecylpyridine segments. Driven by minimizing surface energy, the hydrophilic segments diffuse away from the polypropylene matrix, i.e., towards the surface. The phosphorylcholine groups have a cell membrane-like surface structure, improving the hydrophilicity of the polypropylene matrix surface and constructing a hydration layer barrier. This effectively reduces drug adsorption while also acting as a series dispersed configuration, preventing premature precipitation of the dispersed configuration during high-temperature melting, and improving the dimensional stability of polypropylene. This, in turn, improves the high-temperature resistance of the prepared culture bottles.

[0029] In P(MPC-co-BMC), the phosphorylcholine groups, through dipole-dipole interactions, can help stabilize the ion pairs of 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 1-phosphonaphthyl ester monosodium salt monohydrate, maintaining the uniformity of surface charge distribution. The dipole interactions help to dynamically balance the surface charge, improving the chemical stability of the modifier during high-temperature processing. The dipole interactions can also enhance the interfacial bonding between P(MPC-co-BMC) and the dispersed configuration, maintaining the stability of the dispersed configuration at high temperatures, further strengthening the bonding between the modifier and the polypropylene matrix, promoting heterogeneous nucleation, and refining the grain size. Detailed Implementation

[0030] The present invention will now be described and illustrated in detail with reference to the embodiments.

[0031] The raw materials used in the following examples and comparative examples are all commercially available products. Polypropylene, grade M250E, was provided by Shanghai Petrochemical; hexagonal boron nitride nanosheets were provided by Xi'an Ruixi Biotechnology Co., Ltd.; cellulose nanocrystals were provided by Shanghai Maclean Biochemical Technology Co., Ltd.; P(MPC-co-BMC), which is obtained by copolymerization of two monomers, 2-methacryloyloxyethyl phosphorylcholine (MPC) and n-butyl methacrylate (BMC), was provided by Hangzhou Yuhao Chemical Technology Co., Ltd.

[0032] Example 1

[0033] Weigh out 13 kg of M250E grade polypropylene, 0.8 kg of hexagonal boron nitride nanosheets, 0.65 kg of modifying agents (including 0.25 kg of 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 0.4 kg of 1-naphthyl phosphate monosodium salt monohydrate), 0.6 kg of P(MPC-co-BMC), 0.3 kg of cellulose nanocrystals, 0.3 kg of hexadecylpyridine chloride, 0.1 kg of octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 0.05 kg of polyethylene wax for later use.

[0034] The weighed raw materials (excluding P(MPC-co-BMC)) are fed into a high-speed mixer and mixed at 500 rpm for 70 seconds. Then, P(MPC-co-BMC) is added. Mix for 4 minutes to obtain a mixture; feed the mixture into a twin-screw extruder, which has 6 temperature zones. The temperatures of zones 1, 2, 3, 4, 5, and 6 are set to 180℃, 200℃, 220℃, 220℃, and 215℃ respectively, and the screw speed is set to 200 rpm. After extrusion and granulation, masterbatch is obtained and stored for later use; feed the masterbatch into an injection molding machine, setting the masterbatch melt temperature to 220℃, the injection pressure to 25MPa, the mold temperature to 50℃, and the holding time to 30s. After injection and shaping, a preform is obtained; then the preform is fed into a blow molding machine, setting the blow molding pressure to 0.9MPa and the blow molding mold temperature to 35℃. After blow molding, cooling, and demolding, a culture bottle is obtained.

[0035] The twin-screw extruder, injection molding machine, and blow molding machine used in this embodiment are all commercially available equipment. The same applies to the following embodiments and comparative examples.

[0036] Example 2

[0037] Weigh out 13 kg of M250E grade polypropylene, 0.6 kg of hexagonal boron nitride nanosheets, 0.45 kg of modifying agents (including 0.08 kg of 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 0.37 kg of 1-naphthyl phosphate monosodium salt monohydrate), 0.8 kg of P(MPC-co-BMC), 0.8 kg of cellulose nanocrystals, 0.15 kg of hexadecylpyridine bromide, 0.08 kg of 2,6-di-tert-butyl-p-cresol, and 0.08 kg of paraffin for later use.

[0038] The weighed raw materials (excluding P(MPC-co-BMC)) are fed into a high-speed mixer and mixed at 550 rpm for 80 seconds. Then, P(MPC-co-BMC) is added. Mix for 5 minutes to obtain a mixture; feed the mixture into a twin-screw extruder, which includes 6 temperature zones. The temperatures of zones 1, 2, 3, 4, 5, and 6 are set to 175℃, 195℃, 210℃, 230℃, 230℃, and 220℃ respectively, and the screw speed is set to 150 rpm. After extrusion and granulation, masterbatch is obtained and stored for later use; feed the masterbatch into an injection molding machine, setting the masterbatch melt temperature to 230℃, the injection pressure to 20MPa, the mold temperature to 65℃, and the holding time to 40s. After injection and shaping, a preform is obtained; then the preform is fed into a blow molding machine, setting the blow molding pressure to 0.8MPa and the blow molding mold temperature to 20℃. After blow molding, cooling, and demolding, a culture bottle is obtained.

[0039] Example 3

[0040] Weigh out 13 kg of M250E grade polypropylene, 1 kg of hexagonal boron nitride nanosheets, 0.3 kg of modifying agents (including 0.1 kg of 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 0.2 kg of 1-naphthyl phosphate monosodium salt monohydrate), 0.7 kg of P(MPC-co-BMC), 0.6 kg of cellulose nanocrystals, 0.4 kg of hexadecylpyridine chloride, 0.05 kg of 2,2'-methylenebis-(4-methyl-6-tert-butylphenol), and 0.06 kg of magnesium stearate for later use.

[0041] The weighed raw materials (excluding P(MPC-co-BMC)) are fed into a high-speed mixer and mixed at 600 rpm for 40 seconds. Then, P(MPC-co-BMC) is added. Mix for 3 minutes to obtain a mixture; feed the mixture into a twin-screw extruder, which includes 6 temperature zones. The temperatures of zones 1, 2, 3, 4, 5, and 6 are set to 185℃, 190℃, 200℃, 225℃, 225℃, and 210℃ respectively, and the screw speed is set to 180 rpm. After extrusion and granulation, masterbatch is obtained and stored for later use; feed the masterbatch into an injection molding machine, setting the masterbatch melt temperature to 225℃, the injection pressure to 30MPa, the mold temperature to 35℃, and the holding time to 20s. After injection and shaping, a preform is obtained; then the preform is fed into a blow molding machine, setting the blow molding pressure to 1.0MPa and the blow molding mold temperature to 50℃. After blow molding, cooling, and demolding, a culture bottle is obtained.

[0042] Comparative Example 1

[0043] Without adding hexagonal boron nitride nanosheets, the rest of the operation process and raw materials used are the same as in Example 1.

[0044] Comparative Example 2

[0045] Without adding cellulose nanocrystals, the rest of the operation process and raw materials used are the same as in Example 1.

[0046] Comparative Example 3

[0047] Without adding 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt, the rest of the operation process and raw materials used are the same as in Example 1.

[0048] Comparative Example 4

[0049] Without adding 1-naphthyl phosphate monosodium salt monohydrate, the rest of the operation process and raw materials used are the same as in Example 1.

[0050] Comparative Example 5

[0051] Without adding P (MPC-co-BMC), the rest of the operation process and raw materials used are the same as in Example 1.

[0052] Comparative Example 6

[0053] Without adding hexadecylpyridine chloride, the remaining procedures and raw materials used are the same as in Example 1.

[0054] Implementation effect evaluation

[0055] High-temperature resistance test: Culture bottles prepared in the examples and comparative examples were used. The initial bottle mouth diameter, height, and bottom diameter were recorded. The bottles were kept at 121℃ high-temperature steam for 30 minutes, followed by 135℃ high-temperature steam for 30 minutes, and then naturally cooled to room temperature. The minimum values ​​of the bottle mouth diameter, height, and bottom diameter after the test were recorded, with a dimensional change rate of less than 0.5%. The bottles were visually inspected for obvious deformation, cracking, and inability to tighten the caps. The relevant test results are shown in Table 1.

[0056] Table 1. High Temperature Resistance Test Table for Culture Bottles

[0057]

[0058] Drug adsorption test: The culture bottles prepared in the examples and comparative examples were added to 200 mL of 4-hydroxyethylpiperazine ethanesulfonic acid buffer (pH=7.6) and doxorubicin solution at 10 °C until the doxorubicin concentration was 5.5 μM, which was recorded as C0. The bottles were shaken in a shaker, and samples were taken at four time points: 10 min, 25 min, 50 min, and 100 min to detect the doxorubicin concentration C1.

[0059] In a separate comparative example, commercially available polypropylene (made primarily of polypropylene M250E and containing small amounts of high-density polyethylene 5502 and high-density polyethylene 5000S) culture bottles were used. At 10°C, 200 mL of 4-hydroxyethylpiperazine ethanesulfonic acid buffer (pH=7.6) and doxorubicin solution were added to each bottle until the doxorubicin concentration reached 5.5 μM, denoted as C0. Then, 1 mL of anti-adsorption agent and 0.5 mL of Tween-40 were added. The bottles were shaken in a shaker, and samples were taken at four time points: 10 min, 25 min, 50 min, and 100 min to determine the doxorubicin concentration C1.

[0060] The specific test results of doxorubicin adsorption are shown in Table 2. Adsorption rate = C1 / C0 × 100%.

[0061] Table 2 Test Table of Drug Adsorption in Microbial Culture Bottles

[0062]

[0063] As can be seen from Table 2: (1) When no anti-adsorbent was added, the anti-adsorption effect of the culture bottle prepared by the present invention was better than that of the comparative example in the whole process of 10~100 min. This indicates that when the key components are missing, the effect of the dispersion configuration of the present invention on the modified additive and P(MPC-co-BMC) and the synergistic effect of P(MPC-co-BMC) and dispersion configuration cannot be formed.

[0064] (2) Compared with the direct addition of anti-adsorption agents, the culture bottle prepared by the present invention is directly doped with P(MPC-co-BMC) to form a synergistic effect with the dispersed configuration: the hydrophobic chain ends in P(MPC-co-BMC) are anchored to the dispersed configuration, while the hydrophilic chain segments diffuse to the surface of the polypropylene matrix to form a stable composite hydration layer barrier; while PEG and Tween-40 are surfactants, and the amount used in the culture operation cannot be too high. In addition, PEG and Tween-40 exist in the culture phase in the culture bottle only by physical adsorption. As small molecules or linear polymers, they are easy to migrate after long-term use, and the improvement of the anti-adsorption effect on the inner wall of the bottle is not stable enough.

Claims

1. A culture bottle, characterized in that, By weight, it contains the following components: 130 parts polypropylene, 6-10 parts hexagonal boron nitride nanosheets, 3-6.5 parts modifying agent, 6-8 parts poly(2-methacryloyloxyethyl phosphorylcholine-co-butyl methacrylate), 3-8 parts reinforcing agent, 1.5-4 parts compatibilizer, 0.5-1 part antioxidant, and 0.5-0.8 parts lubricant. The modifying agents include 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 1-naphthyl phosphate monosodium salt monohydrate; the reinforcing agent is cellulose nanocrystals; and the compatibilizer is hexadecylpyridine chloride or hexadecylpyridine bromide.

2. The culture bottle according to claim 1, characterized in that, By mass fraction, 0.8 to 2.5 parts of 1,3,5-triazine-2,4,6(1H,3H,5H)-trithione trisodium salt and 2 to 4 parts of 1-naphthyl phosphate monosodium salt monohydrate.

3. The culture bottle according to claim 1, characterized in that, The antioxidant is one of 2,6-di-tert-butyl-p-cresol, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate or 2,2'-methylenebis-(4-methyl-6-tert-butylphenol); the lubricant is one of magnesium stearate, paraffin or polyethylene wax.

4. A process for preparing a culture bottle according to any one of claims 1-3, characterized in that, Includes the following steps: S1. Polypropylene, hexagonal boron nitride nanosheets, modifiers, reinforcing agents, compatibilizers, antioxidants, and lubricants are premixed, and then poly(2-methacryloyloxyethyl phosphorylcholine-co-butyl methacrylate) is added and mixed to obtain a mixture. S2. The mixture is plasticized to obtain masterbatch; S3. The masterbatch is injection molded to obtain a preform, and the preform is blow molded to obtain a culture bottle.

5. The preparation process of the culture bottle according to claim 4, characterized in that, In S1, the premixing speed is 500~600 rpm, the premixing time is 40~80s, and the mixing time is 3~5min.

6. The preparation process of the culture bottle according to claim 4, characterized in that, In S2, a twin-screw extruder is used for plasticizing. The twin-screw extruder includes six temperature zones: zone 1, zone 2, zone 3, zone 4, zone 5, and zone 6. The temperatures of zone 1, zone 2, zone 3, zone 4, zone 5, and zone 6 are set to 175~185℃, 190~200℃, 200~220℃, 220~230℃, 220~230℃, and 210~220℃, respectively. The speed of the twin-screw extruder is 150~200 rpm.

7. The preparation process of the culture bottle according to claim 4, characterized in that, In S3, an injection molding machine is used for injection molding. The melt temperature of the masterbatch in the injection molding machine is 220~230℃, the injection pressure is 20~30MPa, the mold temperature is 35~65℃, and the holding time is 20~40s.

8. The preparation process of the culture bottle according to claim 4, characterized in that, In S3, blow molding is performed using a blow molding machine with a blow molding pressure of 0.8~1MPa and a blow molding die temperature of 20~50℃.

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