CN116715789A - Preparation method of high-quality crosslinked povidone - Google Patents
Preparation method of high-quality crosslinked povidone Download PDFInfo
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- CN116715789A CN116715789A CN202310041334.2A CN202310041334A CN116715789A CN 116715789 A CN116715789 A CN 116715789A CN 202310041334 A CN202310041334 A CN 202310041334A CN 116715789 A CN116715789 A CN 116715789A
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- CN
- China
- Prior art keywords
- stirring
- purified water
- nitrogen
- polymerization kettle
- crosslinked povidone
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- WHNWPMSKXPGLAX-UHFFFAOYSA-N N-Vinyl-2-pyrrolidone Chemical compound C=CN1CCCC1=O WHNWPMSKXPGLAX-UHFFFAOYSA-N 0.000 title claims abstract description 38
- 229920000036 polyvinylpyrrolidone Polymers 0.000 title claims abstract description 29
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 title claims abstract description 29
- 229940069328 povidone Drugs 0.000 title claims abstract description 29
- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 78
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 39
- 238000003756 stirring Methods 0.000 claims abstract description 34
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 32
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 30
- 239000008213 purified water Substances 0.000 claims abstract description 28
- 230000005587 bubbling Effects 0.000 claims abstract description 19
- 238000005406 washing Methods 0.000 claims abstract description 17
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims abstract description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000001301 oxygen Substances 0.000 claims abstract description 15
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 15
- 238000001914 filtration Methods 0.000 claims abstract description 14
- 238000006243 chemical reaction Methods 0.000 claims abstract description 12
- 238000000034 method Methods 0.000 claims abstract description 10
- 238000010438 heat treatment Methods 0.000 claims abstract description 9
- 239000000203 mixture Substances 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 8
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims abstract description 7
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 7
- 239000000178 monomer Substances 0.000 claims abstract description 7
- 239000012043 crude product Substances 0.000 claims abstract description 6
- 239000007788 liquid Substances 0.000 claims abstract description 6
- 239000000126 substance Substances 0.000 claims abstract description 4
- 238000004806 packaging method and process Methods 0.000 claims abstract description 3
- 238000007873 sieving Methods 0.000 claims abstract description 3
- 239000000047 product Substances 0.000 claims description 14
- 238000001816 cooling Methods 0.000 claims description 7
- 229960000913 crospovidone Drugs 0.000 claims description 7
- 229920000523 polyvinylpolypyrrolidone Polymers 0.000 claims description 7
- 235000013809 polyvinylpolypyrrolidone Nutrition 0.000 claims description 7
- 239000003513 alkali Substances 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 2
- 238000006073 displacement reaction Methods 0.000 claims description 2
- 238000004321 preservation Methods 0.000 claims description 2
- 238000001291 vacuum drying Methods 0.000 claims description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 abstract description 12
- 230000036571 hydration Effects 0.000 abstract description 10
- 238000006703 hydration reaction Methods 0.000 abstract description 10
- 235000011121 sodium hydroxide Nutrition 0.000 abstract description 4
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 239000000463 material Substances 0.000 abstract description 2
- 230000000052 comparative effect Effects 0.000 description 6
- 238000004090 dissolution Methods 0.000 description 5
- 239000003814 drug Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 238000011049 filling Methods 0.000 description 3
- 239000000825 pharmaceutical preparation Substances 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 2
- 238000004132 cross linking Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000002522 swelling effect Effects 0.000 description 1
- 229920003176 water-insoluble polymer Polymers 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F126/00—Homopolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a single or double bond to nitrogen or by a heterocyclic ring containing nitrogen
- C08F126/06—Homopolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a single or double bond to nitrogen or by a heterocyclic ring containing nitrogen by a heterocyclic ring containing nitrogen
- C08F126/10—N-Vinyl-pyrrolidone
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2/00—Processes of polymerisation
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
The invention discloses a preparation method of high-quality crosslinked povidone, which comprises the following steps: adding monomer NVP, purified water and alkali metal hydroxide into a polymerization kettle, starting stirring after all the monomer NVP, purified water and alkali metal hydroxide are added, starting a nitrogen bubbling device, bubbling high-purity nitrogen to remove dissolved oxygen in the reaction liquid, and closing the nitrogen bubbling device; air in the polymerization kettle is replaced by high-purity nitrogen; starting a steam valve of the polymerization kettle to obtain a crude product of the crosslinked povidone; opening a purified water valve of the polymerization kettle, adding purified water into the polymerization kettle, stirring, adding acetic acid to adjust the pH to 3-4, heating to 80 ℃, continuously stirring and washing for 2 hours, adding purified water into the filtered substance, adding liquid caustic soda to adjust the pH to 6-7, and centrifugally filtering to obtain a mixture; drying, controlling water content to be less than 3.0%, sieving, and packaging. The invention optimizes the production process of the conventional crosslinked povidone, and increases the bubbling procedure of high-purity nitrogen to remove the dissolved oxygen in the reaction materials through optimizing the process parameters, thereby obtaining the crosslinked povidone with high hydration capacity.
Description
Technical Field
The invention relates to the technical field of pharmaceutical chemicals, in particular to a preparation method of high-quality crosslinked povidone.
Background
The cross-linked povidone is a high molecular water-insoluble polymer obtained by cross-linking polymerization reaction of N-vinyl pyrrolidone, has very high capillary activity, excellent hydration capacity and larger specific surface area, almost has no gel tendency, and can quickly absorb water into a pharmaceutical preparation, so that the cross-linked povidone is widely used as a super disintegrating agent in various pharmaceutical preparations, so that the preparation quickly swells and disintegrates, and the drug dissolution and bioavailability are effectively improved.
The hydration capacity of the crospovidone is a key functional index affecting the disintegration and dissolution of the medicine, the hydration capacity is not specified in Chinese pharmacopoeia, the hydration capacity is specified in European pharmacopoeia, and the hydration capacity of the crospovidone is 3-9; the hydration capacity of the domestic produced crospovidone is lower and is generally between 3 and 5, so that the disintegration and dissolution effects are poor in the application of the pharmaceutical preparation.
The conventional preparation method of the crosslinked povidone mainly comprises the steps of carrying out self-crosslinking polymerization on N-vinyl pyrrolidone, purified water and sodium hydroxide under a certain condition to obtain a crude crosslinked povidone product, and washing and drying the crude crosslinked povidone product to obtain the crosslinked povidone product.
In the conventional preparation process of the crosslinked povidone, nitrogen is not thoroughly replaced, the reaction system cannot reach the completely anaerobic condition, and the existence of trace oxygen causes slow polymerization reaction and influences the quality of products; and the product has low hydration capability and poor swelling property, so that the medicine has longer disintegration time and poor dissolution effect.
Disclosure of Invention
The invention provides a preparation method of high-quality crosslinked povidone for solving the defects in the prior art.
In order to solve the technical problems, the invention adopts the following technical scheme: a preparation method of high-quality crosslinked povidone comprises the following steps:
nitrogen bubbling and displacement: adding a certain amount of monomer NVP, purified water and alkali metal hydroxide into a polymerization kettle, starting stirring after all the components are added, starting a nitrogen bubbling device, bubbling high-purity nitrogen for a period of time to remove dissolved oxygen in the reaction liquid, and closing the nitrogen bubbling device; then, starting a nitrogen replacement system to replace air in the polymerization kettle with high-purity nitrogen;
polymerization reaction: starting a steam valve of the polymerization kettle, heating to 120-130 ℃, reacting for 3-3.5h at a heat preservation temperature, and then cooling to 90-100 ℃ to react for 2h to obtain a crude product of the crosslinked povidone;
washing: opening a purified water valve of the polymerization kettle, adding purified water into the polymerization kettle, stirring, adding acetic acid to adjust the pH to 3-4, heating to 80 ℃, continuously stirring and washing for 2 hours, and centrifugally filtering after washing is finished; adding purified water into the filtered substances, starting stirring, adding liquid alkali to adjust the pH to 6-7, stirring for 10-20min, and centrifugally filtering to obtain a mixture;
and (3) drying: adding the mixture into a vacuum single cone dryer, vacuum drying at 90-100deg.C, controlling water content to be less than 3.0%, sieving, and packaging.
Preferably, the monomer NVP, purified water, alkali metal hydroxide ratio is: 75-80:20-25:0.5-0.8, and stirring speed is 40-50rpm; the dissolved oxygen in the reaction mass was removed by bubbling with high purity nitrogen.
Preferably, bubbling high-purity nitrogen for 3-4 hours to remove dissolved oxygen in the reaction liquid, vacuumizing, filling nitrogen, and repeating for 4 times until oxygen in the reaction system is completely removed; an initial 0.2MPa nitrogen blanket.
Preferably, in the polymerization reaction, the temperature is reduced to 90-100 ℃ for reaction for 2 hours, then the temperature is reduced to below 50 ℃ and the crude product of the crosslinked povidone is obtained.
Preferably, in the washing process, the initial temperature is 23-25 ℃ at normal temperature.
Preferably, in the washing process, adding liquid alkali to adjust the pH to 6-7, stirring for 10-20min, and centrifugally filtering; after filtration, purified water was further added, stirring was started, stirring was continued for 10-20min, and centrifugal filtration was performed to obtain a mixture, which was the final mixture.
Compared with the prior art, the invention has the following effects: the invention optimizes the production process of the conventional crosslinked povidone, and increases the bubbling procedure of high-purity nitrogen to remove the dissolved oxygen in the reaction materials through optimizing the process parameters, so as to obtain the crosslinked povidone with high hydration capacity, wherein the hydration capacity is more than 6.2; greatly shortens the disintegration time of the medicine and effectively improves the dissolution rate and bioavailability of the medicine.
Detailed Description
The invention will be described in detail with reference to examples.
Example 1
200g of NVP, 50g of purified water and 1.25g of potassium hydroxide are added into a 1L polymerization kettle, stirring is started, the stirring speed is 40rpm, high-purity nitrogen is introduced to bubble for 3 hours, dissolved oxygen in the reaction liquid is removed, and a nitrogen bubbling device is closed; vacuumizing, filling nitrogen, repeating for 4 times, completely removing oxygen in the reaction system, and replacing air in the polymerization kettle with high-purity nitrogen; an initial 0.2MPa nitrogen blanket. Heating to 120 ℃ in the first stage, and reacting for 3h at a temperature; cooling to 100 ℃ for continuous reaction for 2 hours, cooling to below 50 ℃ and discharging to obtain a crude product of the crosslinked povidone;
washing and drying: opening a purified water valve of the polymerization kettle, adding 2L of purified water, starting stirring, adding acetic acid to adjust the pH to 3, heating to 80 ℃, stirring for 2 hours, and filtering; adding the wet product into a 3L flask, adding 2L of purified water, stirring, adding liquid caustic soda to adjust pH to 7, stirring at room temperature for 17min, and filtering; adding the wet product into a 3L flask again, adding 2L of purified water, stirring at room temperature for 17min, and filtering; and (3) drying the wet product at 90 ℃ in vacuum until the moisture is less than 3.0%, thus obtaining 172g of finished product of crosslinked povidone.
Example 2
400kg of monomer NVP, 100kg of purified water and 2.5kg of alkali metal hydroxide are put into a polymerization kettle, stirring is started, the rotating speed is regulated to 40rpm, then a nitrogen bubbling device is started, high-purity nitrogen is introduced to bubble for 3 hours to remove dissolved oxygen in the reaction liquid, and the nitrogen bubbling device is closed; then, starting a nitrogen replacement system, vacuumizing, filling nitrogen, and repeating for 4 times to replace the air in the polymerization kettle with high-purity nitrogen;
polymerization reaction: starting a steam valve of the polymerization kettle, heating to 125 ℃, preserving heat for reaction for 3 hours, and then cooling to 97 ℃ for reaction for 2 hours to obtain a crude product of the crosslinked povidone;
washing: opening a purified water valve of the polymerization kettle, adding 2L of purified water, starting stirring, adding acetic acid to adjust the pH to 3-4, heating to 80 ℃, stirring, washing for 2h, and centrifuging; adding the wet product into a water-washing kettle, adding purified water, starting stirring, adding liquid caustic soda to adjust the pH to 6, stirring at room temperature for 15min, and centrifuging; adding the wet product into a water-washing kettle, adding purified water, stirring at room temperature for 15min, and centrifuging;
and (3) drying: and (3) adding the wet product into a vacuum single cone dryer, drying in vacuum at 97 ℃, and controlling the moisture to be less than 3.0%, thus obtaining 350kg of finished product of crosslinked povidone.
Comparative example 1
In comparison with example 2, the air in the polymerizer was not replaced with high purity nitrogen, and the remainder was the same as in example 2.
Comparative example 2
Compared with example 2, the pH was not continuously adjusted, and the temperature was raised and then the pH was continuously adjusted, in the same manner as in example 2.
Yield tests were carried out on the crospovidone obtained in examples 1-2 and comparative examples 1-2, and specific data are shown in table 1.
TABLE 1
| Example 1 | Example 2 | Comparative example 1 | Comparative example 2 | |
| Yield (%) | 86％ | 87.5％ | 80％ | 78.2％ |
As can be seen from Table 1, the purity of example 2 was higher than that of example 1 and comparative examples 1-2.
The foregoing examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the patent and scope of the invention should be pointed out with reference to the appended claims.
Claims (6)
1. The preparation method of the high-quality crosslinked povidone is characterized by comprising the following steps of:
nitrogen bubbling and displacement: adding a certain amount of monomer NVP, purified water and alkali metal hydroxide into a polymerization kettle, starting stirring after all the components are added, starting a nitrogen bubbling device, bubbling high-purity nitrogen for a period of time to remove dissolved oxygen in the reaction liquid, and closing the nitrogen bubbling device; then, starting a nitrogen replacement system to replace air in the polymerization kettle with high-purity nitrogen;
polymerization reaction: starting a steam valve of the polymerization kettle, heating to 120-130 ℃, reacting for 3-3.5h at a heat preservation temperature, and then cooling to 90-100 ℃ to react for 2h to obtain a crude product of the crosslinked povidone;
washing: opening a purified water valve of the polymerization kettle, adding purified water into the polymerization kettle, stirring, adding acetic acid to adjust the pH to 3-4, heating to 80 ℃, continuously stirring and washing for 2 hours, and centrifugally filtering after washing is finished; adding purified water into the filtered substances, starting stirring, adding liquid alkali to adjust the pH to 6-7, stirring for 10-20min, and centrifugally filtering to obtain a mixture;
and (3) drying: adding the mixture into a vacuum single cone dryer, vacuum drying at 90-100deg.C, controlling water content to be less than 3.0%, sieving, and packaging.
2. The method for preparing high-quality crospovidone according to claim 1, wherein the ratio of monomer NVP, purified water and alkali metal hydroxide is: 75-80:20-25:0.5-0.8, and stirring speed is 40-50rpm; the dissolved oxygen in the reaction mass was removed by bubbling with high purity nitrogen.
3. The method for preparing high-quality crosslinked povidone according to claim 2, wherein the high-purity nitrogen is bubbled for 3-4 hours to remove dissolved oxygen in the reaction liquid, and then the vacuum is pumped, the nitrogen is filled, and the process is repeated for 4 times until oxygen in the reaction system is completely removed; an initial 0.2MPa nitrogen blanket.
4. The method for preparing high-quality crosslinked povidone according to claim 2, wherein in the polymerization reaction, the raw product of crosslinked povidone is obtained by cooling to 90-100 ℃ for 2 hours, then cooling to below 50 ℃ and discharging.
5. A method for preparing high quality crospovidone according to claim 3 wherein the initial temperature in the washing process is 23-25 ℃.
6. The method for preparing high-quality crospovidone according to claim 4, wherein in the washing process, when adding alkali to adjust the pH to 6-7, stirring for 10-20min, and centrifugally filtering; after filtration, purified water was further added, stirring was started, stirring was continued for 10-20min, and centrifugal filtration was performed to obtain a mixture, which was the final mixture.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310041334.2A CN116715789A (en) | 2023-01-13 | 2023-01-13 | Preparation method of high-quality crosslinked povidone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310041334.2A CN116715789A (en) | 2023-01-13 | 2023-01-13 | Preparation method of high-quality crosslinked povidone |
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| Publication Number | Publication Date |
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| CN116715789A true CN116715789A (en) | 2023-09-08 |
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|---|---|---|---|
| CN202310041334.2A Pending CN116715789A (en) | 2023-01-13 | 2023-01-13 | Preparation method of high-quality crosslinked povidone |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6660800B1 (en) * | 2002-10-17 | 2003-12-09 | Arco Chemical Technology, L.P. | Process for making crosslinked polyvinylpyrrolidone |
| CN101935370A (en) * | 2010-08-06 | 2011-01-05 | 安徽山河药用辅料股份有限公司 | Method for preparing polyvinylpolypyrrolidone |
| CN106800616A (en) * | 2016-12-22 | 2017-06-06 | 安徽山河药用辅料股份有限公司 | A kind of preparation method of high bulk density PVPP |
| CN109485771A (en) * | 2018-10-30 | 2019-03-19 | 焦作中维特品药业股份有限公司 | A kind of preparation method of crospovidone |
| CN111378060A (en) * | 2020-03-30 | 2020-07-07 | 衢州建华南杭药业有限公司 | Method for producing crospovidone based on popcorn polymerization mechanism of in-situ generation of cross-linking agent |
-
2023
- 2023-01-13 CN CN202310041334.2A patent/CN116715789A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6660800B1 (en) * | 2002-10-17 | 2003-12-09 | Arco Chemical Technology, L.P. | Process for making crosslinked polyvinylpyrrolidone |
| CN101935370A (en) * | 2010-08-06 | 2011-01-05 | 安徽山河药用辅料股份有限公司 | Method for preparing polyvinylpolypyrrolidone |
| CN106800616A (en) * | 2016-12-22 | 2017-06-06 | 安徽山河药用辅料股份有限公司 | A kind of preparation method of high bulk density PVPP |
| CN109485771A (en) * | 2018-10-30 | 2019-03-19 | 焦作中维特品药业股份有限公司 | A kind of preparation method of crospovidone |
| CN111378060A (en) * | 2020-03-30 | 2020-07-07 | 衢州建华南杭药业有限公司 | Method for producing crospovidone based on popcorn polymerization mechanism of in-situ generation of cross-linking agent |
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