A kind of UV-proof polyvinyl chloride solid medicinal hard tablet and its preparation method

Abstract

The present invention relates to the technical field of pharmaceutical packaging materials, and in particular to a UV-proof polyvinyl chloride solid pharmaceutical hard tablet and a preparation method thereof. The UV-proof polyvinyl chloride solid pharmaceutical hard tablet comprises the following raw materials: polyvinyl chloride resin, methyl methacrylate-butadiene-styrene copolymer, thermal stabilizer, internal lubricant, external lubricant, copolymer of 2-methyl methacrylate and butyl acrylate, and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate. The present invention significantly improves the material's ability to block ultraviolet rays by integrating a specific proportion of high-efficiency UV stabilizers and antioxidant combinations in a PVC matrix, while ensuring the chemical and physical stability of the material during long-term storage.

Description

Technical Field

[0001] The invention relates to the technical field of pharmaceutical packaging materials, and in particular to an anti-ultraviolet polyvinyl chloride solid pharmaceutical hard sheet and a preparation method thereof. Background Art

[0002] In the current pharmaceutical packaging field, polyvinyl chloride (PVC) is widely used in the packaging of a variety of drugs, especially solid drugs, due to its excellent physical and chemical stability properties. PVC not only has excellent barrier properties, high transparency and excellent processing convenience, making it one of the first choices for pharmaceutical packaging materials. However, PVC is highly sensitive to ultraviolet rays, which may cause chemical decomposition during the long-term storage of drugs, thereby adversely affecting the stability and safety of drugs. Ultraviolet radiation may cause the drug to decompose and produce harmful substances, and these decomposition products will reduce the efficacy of the drug. Therefore, it is particularly urgent to develop a PVC pharmaceutical hard sheet that can effectively resist ultraviolet radiation. In addition, the PVC material itself will accelerate aging when exposed to ultraviolet rays, and its internal structure may be damaged, which not only shortens its service life in direct contact packaging applications for drugs, but also may affect the overall safety and reliability of drug packaging.

[0003] For traditional PVC materials, although the overall performance can be improved by adding various stabilizers, antioxidants and UV absorbers to make them better meet the needs of pharmaceutical packaging, the use of these additives is often accompanied by potential migration and long-term safety issues. For example, after long-term contact with drugs, some stabilizers may migrate into the drugs, and this migration may bring potential safety risks. In addition, ordinary PVC materials are prone to accelerated aging under the dual influence of high temperature and light. This aging process is usually manifested as a decrease in physical properties, such as weakening of material strength and yellowing of color. Therefore, in order to overcome these shortcomings, it is urgent to develop a new type of PVC material. This new type of PVC material must not only have higher chemical stability and UV resistance, but also meet more stringent pharmaceutical packaging standards to ensure that the shelf life of the drugs is extended, while ensuring the safety and effectiveness of the drugs during storage and use. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention aims to provide an anti-ultraviolet polyvinyl chloride solid medicinal hard tablet and a preparation method thereof.

[0005] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0006] The invention discloses an anti-ultraviolet polyvinyl chloride solid medicinal hard tablet, which comprises the following raw materials: polyvinyl chloride resin, methyl methacrylate-butadiene-styrene copolymer, heat stabilizer, internal lubricant, external lubricant, copolymer of 2-methyl methacrylate and butyl acrylate and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate.

[0007] Preferably, a UV-resistant polyvinyl chloride solid pharmaceutical hard tablet comprises the following raw materials in percentage by weight:

[0008] Methyl methacrylate-butadiene-styrene copolymer 1-5%;

[0009] Heat stabilizer 0.3-2.0%;

[0010] Internal lubricant 0.1-0.9%;

[0011] External lubricant 0.1-0.4%;

[0012] 2-Copolymer of methyl methacrylate and butyl acrylate 0.3-1.2%;

[0013] Bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate 0.8-3.5%;

[0014] The balance is polyvinyl chloride resin.

[0015] Preferably, a UV-resistant polyvinyl chloride solid pharmaceutical hard tablet comprises the following raw materials in percentage by weight:

[0016] Methyl methacrylate-butadiene-styrene copolymer 2-4%;

[0017] Heat stabilizer 0.5-1.5%;

[0018] Internal lubricant 0.3-0.7%;

[0019] External lubricant 0.15-0.25%;

[0020] 2-Copolymer of methyl methacrylate and butyl acrylate 0.5-1.0%;

[0021] Bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate 1.0-3.0%;

[0022] The balance is polyvinyl chloride resin.

[0023] Preferably, the heat stabilizer is a methyltin heat stabilizer; preferably, the methyltin heat stabilizer is at least one of dimethyltin dithioacetate isooctyl ester, methyltin tris(isooctyl thioglycolate) and coordinated methyltin mercaptan.

[0024] Preferably, the methyl tin heat stabilizer is at least one of YT-181 heat stabilizer and SW-977 heat stabilizer.

[0025] Preferably, the methyl tin heat stabilizer is composed of 50-75wt% YT-181 heat stabilizer and 25-50wt% SW-977 heat stabilizer.

[0026] The invention also provides a method for preparing an ultraviolet-proof polyvinyl chloride solid medicinal hard tablet, which comprises the following steps: raw material mixing, mixing and extruding, calendering and peeling.

[0027] Preferably, the die head temperature is controlled at 120-180° C. in the mixing and extruding step.

[0028] Preferably, the roller temperature in the calendering step is controlled at 170-240°C.

[0029] Preferably, the rotation speed in the calendering step is controlled at 12-25 m / min.

[0030] The UV-proof polyvinyl chloride solid medicinal hard tablet of the present invention is endowed with high mechanical properties, high heat resistance, excellent processing properties and the like after being modified.

[0031] The UV-proof polyvinyl chloride solid medicinal hard sheet of the present invention is a plastic sheet, which is formed into a blister shape after later thermoforming, and is compounded with medicinal aluminum foil to form a blister packaging system; it has UV-proof function and is mainly used for packaging oral solid preparations.

[0032] The PVC blister package prepared from the UV-resistant polyvinyl chloride solid medicinal hard sheet prepared by the present invention has the following characteristics:

[0033] 1. Completely and effectively protect drugs.

[0034] 2. Safety and convenience of medication.

[0035] 3. Unique defensive packaging.

[0036] 4. Green and environmentally friendly packaging, recyclable.

[0037] 5. Suitable for OTC drug packaging, convenient, clear and effective medication guidance. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The present invention is a process flow chart of the production of UV-resistant polyvinyl chloride solid medicinal hard tablets.

[0039] Figure 2 This is a photo of the UV-resistant polyvinyl chloride solid medicinal hard tablet prepared by the present invention. DETAILED DESCRIPTION

[0040] A UV-proof polyvinyl chloride solid medicinal hard tablet, comprising the following raw materials in percentage by weight:

[0041] Methyl methacrylate-butadiene-styrene copolymer 2.7%;

[0042] Heat stabilizer 0.9%;

[0043] Internal lubricant 0.5%;

[0044] External lubricant 0.2%;

[0045] 2-Copolymer of methyl methacrylate and butyl acrylate 0.7%;

[0046] Bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate 1.9%;

[0047] The balance is polyvinyl chloride resin.

[0048] The methyl methacrylate-butadiene-styrene copolymer, referred to as MBS resin, CAS No. 25053-09-2, is used to enhance toughness and improve the impact resistance of the product. M-61 Taiwan Plastics Co., Ltd. was selected.

[0049] The heat stabilizer can be YT-181 heat stabilizer provided by Yunnan Tin Industry Tin Chemical Materials Co., Ltd., the main components of which are dimethyltin dithioacetate (CAS No. 57583-35-4) and methyltin tris(isooctyl thioglycolate) (CAS No. 57583-34-3), appearance and properties: colorless transparent liquid; relative density 1.17, flash point 150°C (closed cup), boiling point 221.1°C. The main function is to prevent the decomposition of polyvinyl chloride.

[0050] The heat stabilizer can also be SW-977 heat stabilizer provided by Hubei Benxing Chemical Co., Ltd., the main component (98%) is coordinated methyltin mercaptan, CAS No. 1208990-22-0. Appearance and properties: colorless transparent liquid; with a slight thiol odor; flash point (closed cup): >96.0℃; density: 1.185×10 3 kg / m 3 ; Slightly soluble in water; Viscosity: 77.25mm 2 / s, pH4.0. The main function is to prevent the decomposition of polyvinyl chloride.

[0051] In order to further improve the thermal stability, the present invention adopts the addition of 5-methylpyrimidine-2,4,6 (1H, 3H, 5H)-trione (CAS No.: 2417-22-3, provided by Shanghai Chuangsai Technology Co., Ltd.) and methyltin heat stabilizer for functional compounding. Specifically, the methyltin heat stabilizer is composed of 40-60wt% YT-181 heat stabilizer, 20-30wt% SW-977 heat stabilizer, and 20-30wt% 5-methylpyrimidine-2,4,6 (1H, 3H, 5H)-trione.

[0052] The internal lubricant is fatty acid polyol partial ester, which improves the free flow of PVC during processing, reduces viscosity, and keeps the residual material between rollers stable. The internal lubricant G62 provided by Hangzhou Zimo Chemical Co., Ltd. is selected.

[0053] The external lubricant is a multifunctional fatty acid ester, which improves the demoulding effect during the product processing and can significantly improve the PVC calendering process. The external lubricant G70S provided by Hangzhou Zimo Chemical Co., Ltd. is selected.

[0054] The copolymer of 2-methyl methacrylate and butyl acrylate, Butyl acrylate-methylmethacrylate polymers, CAS No. 25852-37-3, is used to improve processing performance. The P-201 processing aid or P-251 processing aid provided by Taiwan Plastics Industry Co., Ltd. is selected.

[0055] The light stabilizer bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, referred to as light stabilizer 770, has a CAS number of 52829-07-9. Light stabilizer 770 provided by Suqian Liansheng Additive Co., Ltd. is selected. Light stabilizer 770 is a low molecular weight, high-efficiency hindered amine light stabilizer, which has good compatibility with most polymers and has excellent synergistic effect when used with antioxidants and ultraviolet absorbers.

[0056] The polyvinyl chloride resin, polyvinyl chloride, English abbreviation PVC (Polyvinyl chloride), is a polymer formed by the polymerization of vinyl chloride monomer (VCM) in the presence of initiators such as peroxides and azo compounds; or under the action of light and heat according to the free radical polymerization mechanism. Vinyl chloride homopolymers and vinyl chloride copolymers are collectively referred to as polyvinyl chloride resins. PVC for pharmaceutical packaging is a white powder with an amorphous structure, a small degree of branching, a relative density of about 1.4, a glass transition temperature of 77-90°C, and begins to decompose at about 170°C. It has poor stability to light and heat. It will decompose at temperatures above 100°C or after long-term exposure to sunlight to produce hydrogen chloride, and further autocatalytic decomposition, causing discoloration, and the physical and mechanical properties also decline rapidly. In practical applications, stabilizers must be added to improve the stability to heat and light.

[0057] The molecular weight of industrially produced PVC is generally in the range of 50,000-110,000, with large polydispersity. The molecular weight increases with the decrease of polymerization temperature. It has no fixed melting point, starts to soften at 80-85℃, becomes viscoelastic at 130℃, and starts to change into viscous flow at 160-180℃. It has good mechanical properties, with a tensile strength of about 60MPa and an impact strength of 5-10kJ / m 2 ; Has excellent dielectric properties.

[0058] The natural color of PVC is slightly yellow and translucent, with a glossy appearance. Its transparency is better than that of polyethylene and polypropylene, but worse than that of polystyrene. Depending on the amount of additives used, it is divided into soft and hard PVC. Soft products are soft and tough, and feel sticky. The hardness of hard products is higher than that of low-density polyethylene, but lower than that of polypropylene, and whitening will occur at the bends. It has stable chemical properties; it is not easily corroded by acids and alkalis; it is relatively resistant to heat.

[0059] Polyvinyl chloride has the advantages of flame retardancy (flame retardancy value of 40 or more), high chemical resistance (resistance to concentrated hydrochloric acid, 90% sulfuric acid, 60% nitric acid and 20% sodium hydroxide), good mechanical strength and electrical insulation.

[0060] PVC has poor light and heat stability. The softening point is 80℃, and it starts to decompose at 130℃. Without heating the stabilizer, PVC starts to decompose at 100℃, and decomposes faster above 130℃. When heated, it releases hydrogen chloride gas, which changes its color from white to light yellow to red to brown to black. Ultraviolet rays and oxygen in sunlight can cause photo-oxidative decomposition of PVC, thereby reducing the flexibility of PVC and finally making it brittle. It has stable physical and chemical properties, is insoluble in water, alcohol, and gasoline, and has low gas and water vapor permeability; it can withstand any concentration of hydrochloric acid, sulfuric acid below 90%, nitric acid below 50-60%, and caustic soda solution below 20% at room temperature, and has a certain resistance to chemical corrosion; it is quite stable to salts, but can be dissolved in organic solvents such as ether, ketones, chlorinated aliphatic hydrocarbons and aromatic hydrocarbons.

[0061] Rigid polyvinyl chloride (without plasticizer) has good mechanical strength, weather resistance and flame retardancy. It can be used alone as a structural material and applied in the chemical industry to manufacture pipes, plates and injection molded products. Some high-quality products are used in the production of pharmaceutical packaging.

[0062] Specifically, TL-800 polyvinyl chloride resin provided by Tianjin LG Bohai Chemical Co., Ltd. can be used. Appearance and properties: white or light yellow powder; odor: odorless; relative density (water=1): 1.41; solubility: insoluble in most organic solvents; average molecular weight: 43374; degree of polymerization: 780-840.

[0063] Or use HG-800 polyvinyl chloride resin provided by Hanwha Chemical (Ningbo) Co., Ltd., appearance and properties: white or light yellow powder; appearance change: the color will change under heating or light conditions; odor: odorless; relative density (water = 1): 1.41; solubility: insoluble in water; molecular weight: 47499.10-52499.00; degree of polymerization: 760-840.

[0064] The present invention also provides a method for preparing a UV-resistant polyvinyl chloride solid medicinal hard tablet, comprising the following steps: raw material mixing, mixing and extruding, calendering and peeling;

[0065] Raw material mixing: Mix the raw materials evenly according to the ratio;

[0066] Mixing and extrusion: Use a planetary screw extruder to mix and extrude the raw materials, and control the die temperature at 120-180℃;

[0067] Calendering: The molten material is processed into a film through a calender, the roller temperature is controlled at 170-240℃, and the speed is controlled at 12-25m / min.

[0068] Stripping: The calendered film is processed by stripping rollers and cooling rollers.

[0069] The core process is described in detail as follows:

[0070] Mixing and extrusion: Use a planetary screw extruder to mix the materials. The material is pushed from the feeding section to the planetary section, and under the continuous and strong push of the rear screw feed, it moves to the extrusion of the front head of the screw, passing through the internal thread teeth between the main screw and the barrel and the meshing planetary screw teeth. The screws in the planetary section rotate continuously, so that the material is subjected to strong extrusion, rolling and shearing forces in the gap between the meshing and rotating thread teeth. The material is constantly turned and mixed in this section, and finally becomes a molten state and is evenly plasticized. The key to this process is to control the temperature of the sleeve to cooperate with the shearing and internal friction of the material to enhance plasticization. The temperature is controlled at 120-180℃ according to the formula and material characteristics. At this temperature, the material is plasticized evenly, and there is no obvious decomposition under the action of the heat stabilizer in the formula. The material is uniform and suitable for calendering.

[0071] Calendering: During the entire forming process of calendered products, the influence of various process parameters of the calender is the most critical. It is an important condition to ensure the quality of product forming. During the calendering process of the sheet, the temperature and speed of the rollers in the calender, the speed ratio between the rollers, the working surface gap between the rollers, and the amount of molten material between two adjacent rollers are all major factors affecting the forming quality of the calendered products.

[0072] 1) The temperature of the roller is one of the important conditions to ensure that the calendered plastic is rolled into a film in a molten state. The temperature of the roller mainly comes from the heat-conducting oil, a heat-conducting medium, which is input into the roller body. It circulates inside the roller, performs heat exchange, and heats the roller body, causing the roller temperature to gradually rise. Another factor is that during the roller calendering of plastics, the rolling friction between the roller and the raw material and the shear friction between the raw materials generate heat, which will also cause the roller temperature to change. The amount of heat generated by the shear friction between the raw materials is related to the working speed of the roller and the viscosity of the raw material itself: the higher the roller speed and the greater the viscosity of the raw material, the more friction heat is generated; otherwise, the less friction heat is generated. The temperature of the roller is generally controlled between 170-240℃. Since the calendered melt is easy to be wrapped on the roller with high roller temperature and fast speed, the roller temperature control of the roller should be that the sheet roller is higher than the sheet feeding roller, and the temperature difference between the rollers is generally controlled between 5-10℃. In the case of special products, the temperature of the last sheet roller is slightly lower than the previous roller.

[0073] 2) Roller speed The speed of the roller is generally controlled according to the raw material properties and thickness of the calendered product. Usually, when producing rigid polyvinyl chloride products, the roller speed is controlled at 12-25m / min.

[0074] The speed ratio between the rollers refers to the ratio of the linear speeds of the roller working surfaces. There is a certain speed ratio between the rollers for adjusting the forming of calendered products, the purpose is to make the calendered molten material adhere to the roller surface of the fast roller more smoothly. The speed difference between adjacent rollers increases the shearing effect of the molten material and extends it, improving the plasticization quality of the molten material; in this way, the product quality is also improved at the same time. The size of the speed ratio between the rollers is related to the roller speed and the thickness of the product. If the speed ratio is adjusted according to the wrapping of the molten material, it should be based on the molten material neither wrapping the roller nor sucking the roller. If the speed difference between the rollers is too large, the roller wrapping phenomenon will occur; if the speed difference between the rollers is too small, air is easily trapped, the sheet sucks the roller poorly, and bubbles are easily generated in the product. The speed ratio between the rollers is basically controlled at about 1: (1.1-1.2) times, preferably 1: 1.15.

[0075] 3) Roller temperature and roller speed When adjusting and controlling the roller temperature during the production of calendered plastic products, attention should be paid to the mutual influence of roller speed and roller temperature. The fast or slow change of roller speed affects the shearing and extension of the raw materials during calendering, and the heat generated by the friction between the raw materials also changes accordingly. In this way, the roller temperature will also rise and fall accordingly. Therefore, attention should be paid to the influence relationship between them during production operation: if one of the two changes, the other should also be adjusted accordingly, so as to ensure smooth production and stable product quality.

[0076] 4) Roller gap adjustment Roller gap refers to the distance between the working surfaces of each roller. This roller distance (also the gap between the working surfaces of the rollers) is to control the thickness of the product and the amount of melt between the rollers. The gap between the rollers is adjusted based on the gap between the last set of rollers that produce the film. This gap is close to the molding thickness of the product.

[0077] 5) The amount of stock between the rollers during production should be adjusted appropriately according to the surface quality of the molded product: when there is too much stock, the molten material does not rotate well between the two rollers, which can easily cause bubbles on the surface of the plastic film, and the thickness deviation of the product fluctuates greatly, making the product quality unstable. If there is too little stock between the two rollers, the film edge may crack or break due to the unstable amount of material entering the gap between the rollers. For the calendering of hard sheets, too much stock between the rollers can easily cause scars on the surface of the product and increase the operating load of the rollers.

[0078] Stripping and cooling system: The post-processing work after calendering of polyvinyl chloride sheets, that is, the speed adjustment of the stripping roller and the cooling roller, also has a great influence on the quality of the products. In order to ensure the stability of the production quality of calendered products and make the production of calendered plastic products go smoothly, the working speed of the stripping roller and the cooling roller must match and coordinate with the speed of the calender roller.

[0079] 1) Adjustment of the speed of the stripping roller The speed of the stripping roller has a significant impact on the quality of the product. In general, the speed of the stripping roller should be slightly faster than that of the roller. When the material rolls, it means that the speed of the stripping roller is slow. The speed of the stripping roller should be adjusted faster to increase the speed difference between the stripping roller and the calender roller. If the film is severely stretched after being stripped, it means that the speed of the stripping roller is too fast. The speed of the stripping roller should be appropriately slowed down to reduce the speed difference between the stripping roller and the calender roller.

[0080] 2) Adjustment of the speed of the cooling roller. The speed of this group of rollers should be slightly faster than that of the stripping roller. The rollers in this group of rollers are arranged in the running order and basically maintain the same speed. The sheet should be kept slightly tense when running here. In order to ensure the quality of the product and avoid the sheet from generating large internal stress or shrinkage, pay attention to the adjustment of the cooling roller speed, which should be based on not causing cold stretching of the product.

[0081] The present invention provides a novel UV-proof polyvinyl chloride solid pharmaceutical hard sheet and a preparation method thereof. The hard sheet significantly improves the material's ability to block UV rays by integrating a specific proportion of a high-efficiency UV stabilizer and an antioxidant combination in a PVC matrix, while ensuring the chemical and physical stability of the material during long-term storage. This innovative PVC pharmaceutical hard sheet can not only effectively extend the shelf life of drugs, but also ensure the efficacy and safety of drugs by preventing the generation of harmful substances, meeting the high standards of modern drug packaging.

[0082] Example 1

[0083] A UV-resistant polyvinyl chloride solid medicinal hard tablet, the raw materials are composed of the following mass percentages:

[0084] Methyl methacrylate-butadiene-styrene copolymer M-61 2.7％ Methyl tin heat stabilizer YT-181 0.9％ Internal lubricant G62 0.5％ External lubricant G70S 0.2％ P-201 processing aid 0.7％ Light Stabilizer 770 1.9％ TL-800 polyvinyl chloride resin margin.

[0085] The method for preparing the UV-resistant polyvinyl chloride solid medicinal hard tablet comprises the following steps: raw material mixing, mixing and extruding, calendering and peeling;

[0086] Raw material mixing: Mix the raw materials evenly according to the ratio;

[0087] Compounding and extrusion: Use planetary screw extruder to compound and extrude the raw materials;

[0088] Calendering: The molten material is processed into a film through a calender;

[0089] Stripping: The calendered film is processed by stripping rollers and cooling rollers.

[0090] A 0.30 mm thick UV-resistant polyvinyl chloride solid medicinal hard sheet was prepared.

[0091] Production line: Tianlixing 2# production line, temperature: ℃, speed: m / min

[0092]

[0093] The process flow chart of the production of UV-resistant polyvinyl chloride solid medicinal hard tablets of the present invention is shown in Figure 1 ; The actual photo of the UV-proof polyvinyl chloride solid medicinal hard tablet prepared in Example 1 is shown in Figure 2 .

[0094] Example 2

[0095] A UV-resistant polyvinyl chloride solid medicinal hard tablet, the raw materials are composed of the following mass percentages:

[0096] Methyl methacrylate-butadiene-styrene copolymer M-61 2.7％ Methyltin heat stabilizer SW-977 0.9％ Internal lubricant G62 0.5％ External lubricant G70S 0.2％ P-201 processing aid 0.7％ Light Stabilizer 770 1.9％ TL-800 polyvinyl chloride resin margin.

[0097] The preparation method of the UV-resistant polyvinyl chloride solid medicinal hard tablet is the same as that of Example 1.

[0098] Example 3

[0099] A UV-resistant polyvinyl chloride solid medicinal hard tablet, the raw materials are composed of the following mass percentages:

[0100] Methyl methacrylate-butadiene-styrene copolymer M-61 2.7％ Methyltin heat stabilizer SW-977 0.3％ Methyl tin heat stabilizer YT-181 0.6％ Internal lubricant G62 0.5％ External lubricant G70S 0.2％ P-201 processing aid 0.7％ Light Stabilizer 770 1.9％ TL-800 polyvinyl chloride resin margin.

[0101] The preparation method of the UV-resistant polyvinyl chloride solid medicinal hard tablet is the same as that of Example 1.

[0102] Example 4

[0103] A UV-resistant polyvinyl chloride solid medicinal hard tablet, the raw materials are composed of the following mass percentages:

[0104]

[0105]

[0106] The preparation method of the UV-resistant polyvinyl chloride solid medicinal hard tablet is the same as that of Example 1.

[0107] Example 5

[0108] A UV-resistant polyvinyl chloride solid medicinal hard tablet, the raw materials are composed of the following mass percentages:

[0109] Methyl methacrylate-butadiene-styrene copolymer M-61 2.7％ 5-Methylpyrimidine-2,4,6(1H,3H,5H)-trione 0.9％ Internal lubricant G62 0.5％ External lubricant G70S 0.2％ P-201 processing aid 0.7％ Light Stabilizer 770 1.9％ TL-800 polyvinyl chloride resin margin.

[0110] The preparation method of the UV-resistant polyvinyl chloride solid medicinal hard tablet is the same as that of Example 1.

[0111] Test Example 1:

[0112] Aging test was performed on Examples 1-3: 180° C., constant temperature oven, visual inspection.

[0113] Table 1

[0114] 25min 30min 35min 40min 45min 50min 55min 60min Example 1 No color change No color change Slightly yellow Slightly yellow Yellowing Yellowing Dark yellow brown Example 2 No color change Slightly yellow Slightly yellow Slightly yellow Yellowing Dark yellow Dark yellow brown Example 3 No color change No color change No color change No color change Slightly yellow Slightly yellow Yellowing Dark yellow

[0115] Color depth classification: brown > dark yellow > yellowing > slightly yellow > no color change.

[0116] Test Example 2:

[0117] The tensile strength and elongation at break of Example 1 were tested according to YBB00212005-2015.

[0118] Table 2

[0119]

[0120] Test Example 3:

[0121] A heating expansion test was performed on Example 1 according to YBB00292004-2015, in a constant temperature oven at 100° C. for 10 min.

[0122] Table 3

[0123]

[0124] Test Example 4:

[0125] The UV aging resistance was evaluated using a UVA-340 lamp as the light source to simulate sunlight exposure. The test period was 168 hours, divided into 14 cycles, each cycle including an 8-hour drying phase (irradiance of 0.76 W / m at a wavelength of 340 nm). 2 ×nm, blackboard temperature was controlled at 60°C) and 4 hours of condensation phase (irradiance was 0.00 W / m 2 ×nm, the blackboard temperature dropped to 50°C). The determination of tensile strength retention rate follows the YBB00212005-2015 standard, and the tensile strength of the sample after UV aging is compared with that before aging, expressed as a percentage (%), to evaluate the aging resistance of the material.

[0126] Table 4

[0127] Longitudinal tensile strength retention rate / % Example 1 94.3 Example 2 92.5 Example 3 96.4 Example 4 98.7 Example 5 97.6

[0128] Test Example 5:

[0129] The yellowing index (ΔYI) of UV aging (30W UV lamp irradiation for 50 days) is in accordance with the plastic yellowness index test method in GB / T 39822-2021 "Determination of plastic yellowness index and its change value".

[0130] Table 5

[0131] Yellowing index / % Example 1 1.5 Example 2 1.9 Example 3 0.8 Example 4 0.4 Example 5 0.5

[0132] In Example 3, the combination of methyltin heat stabilizer YT-181 and SW-977 shows obvious synergistic effect, significantly improving the thermal stability of polyvinyl chloride (PVC). YT-181, including dithioacetic acid isooctyl dimethyltin and methyltin tris (thioglycolic acid isooctyl ester), mainly reacts with the hydrogen chloride released in the PVC processing process, effectively neutralizes these acidic substances, prevents them from accelerating the fracture and degradation of PVC chains. Meanwhile, the coordination type mercaptan methyltin in SW-977 utilizes its thiol group to react with the free radicals produced in the PVC decomposition process, stabilizes these reactive substances, suppresses the chain reaction caused by free radicals, thereby slowing down the aging and physical property decay of the material. This synergistic effect makes the two combined than providing more comprehensive protection when used alone, not only enhancing the chemical stability of the material, but also optimizing the physical property maintenance of PVC under high temperature conditions, thereby extending the service life of PVC products and improving its reliability in pharmaceutical packaging.

Claims

1. A UV-proof polyvinyl chloride solid medicinal hard tablet, characterized in that: Including the following raw materials in mass percentage: Methyl methacrylate-butadiene-styrene copolymer 1-5%; Heat stabilizer 0.3-2.0%; Internal lubricant 0.1-0.9%; External lubricant 0.1-0.4%; 2-Copolymer of methyl methacrylate and butyl acrylate 0.3-1.2%; Bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate 0.8-3.5%; The balance is polyvinyl chloride resin; The heat stabilizer consists of 50-75wt% YT-181 heat stabilizer and 25-50wt% SW-977 heat stabilizer, or the heat stabilizer consists of 40-60wt% YT-181 heat stabilizer, 20-30wt% SW-977 heat stabilizer, and 20-30wt% 5-methylpyrimidine-2,4,6(1H,3H,5H)-trione.

2. The UV-resistant polyvinyl chloride solid pharmaceutical hard tablet according to claim 1, characterized in that: Including the following raw materials in mass percentage: Methyl methacrylate-butadiene-styrene copolymer 2-4%; Heat stabilizer 0.5-1.5%; Internal lubricant 0.3-0.7%; External lubricant 0.15-0.25%; 2-Copolymer of methyl methacrylate and butyl acrylate 0.5-1.0%; Bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate 1.0-3.0%; The balance is polyvinyl chloride resin.

3. The method for preparing the UV-resistant polyvinyl chloride solid pharmaceutical hard tablet according to claim 1 or 2, characterized in that: The process comprises the following steps: mixing of raw materials, kneading and extrusion, calendaring and stripping.

4. The method for preparing the UV-resistant polyvinyl chloride solid pharmaceutical hard tablet according to claim 3, characterized in that: In the mixing and extruding step, the die head temperature is controlled at 120-180°C.

5. The method for preparing the UV-resistant polyvinyl chloride solid medicinal hard tablet according to claim 3, characterized in that: The roller temperature is controlled at 170-240°C during the calendering step.

6. The method for preparing the UV-resistant polyvinyl chloride solid pharmaceutical hard tablet according to claim 5, characterized in that: The rotation speed in the calendering step is controlled at 12-25 m / min.

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