Material containing modified 6-chloro-1H-pyrazolo [4, 3-C] pyridine-alcohol and preparation method thereof
By modifying the combination of 6-chloro-1H-pyrazolo[4,3-C]pyridin-ol with polyurethane and calcium carbonate, a material with improved flame retardant effect was prepared, which solved the problem of insufficient flame retardant effect in the prior art, while maintaining good antibacterial properties.
Patent Information
- Application Number
- CN202411934842.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-05-13
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The existing 6-chloro-1H-pyrazolo[4,3-c]pyridin-ol exhibits significant activity in antibacterial aspects, but its flame retardant effect has not been improved, limiting its application field.
Materials with improved flame retardant effects were prepared by extruding modified 6-chloro-1H-pyrazolo[4,3-C]pyridin-ol, polyurethane and calcium carbonate in a twin-screw extruder and molding in a flat vulcanizer.
The material forms a carbon layer and releases sulfate or sulfur dioxide at high temperatures, significantly slowing down the combustion rate, improving the flame retardant effect, while retaining good antibacterial properties.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of materials, in particular to a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol and a preparation method thereof. Background Art
[0002] 6-Chloro-1H-pyrazolo[4,3-c]pyridine-alcohol is an organic compound with the chemical formula C6H3Cl2N3·xH2O, usually in the form of light yellow or off-white powder. This compound has a wide range of applications in the fields of medicine and pesticides, especially in antibacterial properties, but its flame retardant effect has not been improved, which greatly limits its application areas. Therefore, how to avoid this phenomenon is the key to solving the problem. Summary of the invention
[0003] 1. Technical issues to be resolved In view of the deficiencies in the prior art, the present invention provides a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol and a preparation method thereof, which has good antibacterial and flame retardant effects.
[0004] (II) Technical solution To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, characterized in that it comprises the following components by weight: 5-10 parts by weight of modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, 25-40 parts by weight of polyurethane, and 1-3 parts by weight of calcium carbonate.
[0005] Preferably, the preparation method of the modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is: (1) 0.68-0.71 g of chitosan was dissolved in 1% acetic acid solution, and then an initiator 1-hydroxybenzotriazole monohydrate was added to react for 0.4-0.6 h, and then 0.3-0.5 g of (3-carboxypropyl) triphenylphosphonium bromide was added thereto, and nitrogen was introduced for protection, and the reaction was carried out at 70-90 ° C for 12-14 h, and then 0.5-0.9 g of acrylic acid was added, and the reaction was continued for 40-50 min. After the reaction, the reaction was dialyzed with a dialysis bag with a molecular weight cutoff of 3500 for 2-3 days to obtain modified chitosan; (2) adding modified chitosan to N,N-dimethylformamide solvent, stirring and dispersing, then adding mercaptoethylamine and benzoin dimethyl ether photoinitiator, irradiating with ultraviolet light for 3-5 hours at 20-40° C., centrifuging, washing and drying to obtain intermediate 1; (3) adding intermediate 1 and 1,3-propane sultone to acetone solvent for dissolution, then dropping a 2-5% sodium hydroxide solution, reacting at 60-85° C. for 6-10 hours, concentrating under reduced pressure to remove the solvent, and recrystallizing the crude product in ethanol to obtain intermediate 2; (4) Add intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol to N,N-dimethylformamide solvent, stir and mix, and react at 90-110°C for 5-8 hours. After reaction, evaporate under reduced pressure and wash to obtain modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol.
[0006] Preferably, the mass of the initiator 1-hydroxybenzotriazole monohydrate in (1) is 0.01-0.02 g.
[0007] Preferably, the mass ratio of the modified chitosan, mercaptoethylamine and benzoin dimethyl ether photoinitiator in (2) is 1:1.2-1.3:0.01-0.02.
[0008] Preferably, the mass ratio of the intermediate 1 to 1,3-propane sultone in (3) is 0.6-1.1:1.
[0009] Preferably, the mass ratio of the intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol in (4) is 1:2.1-2.3.
[0010] Preferably, the preparation method of the polyurethane is as follows: dewatering the polyether diol and mixing it evenly with hexamethylene diisocyanate, introducing nitrogen, then dropping a dibutyltin dilaurate catalyst, reacting at 50-80°C for 2-4h to perform prepolymerization, then adding the intermediate 1, stirring to continue the chain extension reaction, reacting for 20-30min, cooling, discharging, and obtaining the polyurethane; wherein the mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and the intermediate 1 is 1.2-2:1:0.01-0.02:0.4-0.8.
[0011] Preferably, the preparation method of the material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is as follows: modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, polyurethane and calcium carbonate are extruded and granulated at 180-190°C in a twin-screw extruder, and then the granules are molded in a flat vulcanizer at 8-9MPa pressure and 185-190°C to obtain the material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol. (III) Beneficial Technical Effects The invention provides a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol by extruding modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, polyurethane and calcium carbonate in a twin-screw extruder to form granules, and then molding the granules in a flat vulcanizer to obtain the modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol material. The sulfur element contained in the modified chitosan and polyurethane can promote the formation of a carbon layer on the polymer surface at high temperature. This carbon layer can serve as a barrier layer for heat and oxygen, thereby slowing down the combustion rate and playing a flame retardant role. The sulfur element in the sodium sulfonate contained therein will release sulfate or sulfur dioxide at high temperature. These substances can dilute the oxygen in the air to a certain extent and also have a flame retardant effect. The chitosan contained therein also has a good antibacterial effect, and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol also has a good antibacterial effect. DETAILED DESCRIPTION Example 1
[0012] (1) 0.68 g of chitosan was dissolved in 1% acetic acid solution, and then 0.01 g of initiator 1-hydroxybenzotriazole monohydrate was added to react for 0.4 h, and then 0.3 g of (3-carboxypropyl) triphenylphosphonium bromide was added thereto, and nitrogen was introduced to protect the reaction at 70 °C for 12 h, and then 0.5 g of acrylic acid was added and the reaction was continued for 40 min. After the reaction, the solution was dialyzed for 2 days using a dialysis bag with a molecular weight cutoff of 3500 to obtain modified chitosan; (2) Adding modified chitosan to N,N-dimethylformamide solvent, stirring and dispersing, and then adding mercaptoethylamine and benzoin dimethyl ether photoinitiator, wherein the mass ratio of modified chitosan, mercaptoethylamine, and benzoin dimethyl ether photoinitiator is 1:1.2:0.01, irradiating with ultraviolet light at 20°C for h, centrifuging after irradiation, washing and drying to obtain intermediate 1; (3) adding intermediate 1 and 1,3-propane sultone to acetone solvent for dissolution, wherein the mass ratio of intermediate 1 to 1,3-propane sultone is 0.6:1, then dropping a 2% sodium hydroxide solution, reacting at 60° C. for 6 h, concentrating under reduced pressure to remove the solvent after the reaction, and recrystallizing the crude product in ethanol to obtain intermediate 2; (4) Adding intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol to N,N-dimethylformamide solvent, wherein the mass ratio of intermediate 2 to 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is 1:2.1, stirring and mixing, stirring and reacting at 90°C for 5 hours, and then distilling under reduced pressure and washing to obtain modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol; (5) After removing water from the polyether diol, the mixture was mixed evenly with hexamethylene diisocyanate, nitrogen was introduced, and then dibutyltin dilaurate catalyst was added dropwise, and the mixture was reacted at 50° C. for 2 hours for prepolymerization, and then intermediate 1 was added and stirred to continue the chain extension reaction. After reacting for 20 minutes, the mixture was cooled and discharged to obtain polyurethane; wherein the mass ratio of polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and intermediate 1 was 1.2:1:0.01:0.4; (6) 5 parts by weight of modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, 25 parts by weight of polyurethane and 1 part by weight of calcium carbonate are extruded into pellets in a twin-screw extruder at 180°C, and then the pellets are compression molded in a flat plate vulcanizer at a pressure of 8 MPa and at 185°C to obtain a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol. Example 2
[0013] (1) 0.71 g of chitosan was dissolved in 1% acetic acid solution, and then 0.02 g of initiator 1-hydroxybenzotriazole monohydrate was added to react for 0.6 h, and then 0.5 g of (3-carboxypropyl) triphenylphosphonium bromide was added, and nitrogen was introduced to react at 90 ° C for 14 h, and then 0.9 g of acrylic acid was added and the reaction was continued for 50 min. After the reaction, it was dialyzed for 3 days with a dialysis bag with a molecular weight cutoff of 3500 to obtain modified chitosan; (2) Add modified chitosan to N,N-dimethylformamide solvent, stir and disperse, then add mercaptoethylamine and benzoin dimethyl ether photoinitiator, wherein the mass ratio of modified chitosan, mercaptoethylamine and benzoin dimethyl ether photoinitiator is 1:1.3:0.02, irradiate with ultraviolet light at 40°C for 5 hours, centrifuge and separate after irradiation, wash and dry to obtain intermediate 1; (3) adding intermediate 1 and 1,3-propane sultone to acetone solvent for dissolution, wherein the mass ratio of intermediate 1 to 1,3-propane sultone is 1.1:1, then adding dropwise a 5% sodium hydroxide solution, reacting at 85°C for 10 hours, and concentrating under reduced pressure to remove the solvent after the reaction, and the crude product is recrystallized in ethanol to obtain intermediate 2; (4) Adding intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol to N,N-dimethylformamide solvent, wherein the mass ratio of intermediate 2 to 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is 1:2.3, stirring and mixing, stirring and reacting at 110° C. for 8 h, and then distilling under reduced pressure and washing to obtain modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol; (5) After removing water from the polyether diol, the mixture was mixed evenly with hexamethylene diisocyanate, nitrogen was introduced, and then dibutyltin dilaurate catalyst was added dropwise, and the mixture was reacted at 80° C. for 4 hours for prepolymerization, and then intermediate 1 was added and stirred to continue the chain extension reaction. After reacting for 30 minutes, the mixture was cooled and discharged to obtain polyurethane; wherein the mass ratio of polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and intermediate 1 was 2:1:0.02:0.8; (6) 10 parts by weight of modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, 40 parts by weight of polyurethane and 3 parts by weight of calcium carbonate are extruded into pellets in a twin-screw extruder at 190° C., and then the pellets are compression molded in a flat vulcanizer at a pressure of 9 MPa and at 190° C. to obtain a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol. Example 3
[0014] (1) 0.69 g of chitosan was dissolved in 1% acetic acid solution, and then 0.015 g of initiator 1-hydroxybenzotriazole monohydrate was added to react for 0.5 h, and then 0.4 g of (3-carboxypropyl)triphenylphosphonium bromide was added, and nitrogen was introduced to react at 80 ° C for 13 h, and then 0.8 g of acrylic acid was added and the reaction was continued for 45 min. After the reaction, it was dialyzed for 2 days with a dialysis bag with a molecular weight cutoff of 3500 to obtain modified chitosan; (2) Add modified chitosan to N,N-dimethylformamide solvent, stir and disperse, then add mercaptoethylamine and benzoin dimethyl ether photoinitiator, wherein the mass ratio of modified chitosan, mercaptoethylamine and benzoin dimethyl ether photoinitiator is 1:1.5:0.02, irradiate with ultraviolet light at 30°C for 4 hours, centrifuge, wash and dry to obtain intermediate 1; (3) adding intermediate 1 and 1,3-propane sultone to acetone solvent for dissolution, wherein the mass ratio of intermediate 1 to 1,3-propane sultone is 0.8:1, then adding dropwise a 3% sodium hydroxide solution, reacting at 75°C for 8 hours, and concentrating under reduced pressure to remove the solvent after the reaction, and the crude product is recrystallized in ethanol to obtain intermediate 2; (4) Adding intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol to N,N-dimethylformamide solvent, wherein the mass ratio of intermediate 2 to 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is 1:2.2, stirring and mixing, stirring and reacting at 100° C. for 6 h, and then distilling under reduced pressure and washing to obtain modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol; (5) After removing water from the polyether diol, the mixture was mixed evenly with hexamethylene diisocyanate, nitrogen was introduced, and then dibutyltin dilaurate catalyst was added dropwise, and the mixture was reacted at 70° C. for 3 hours for prepolymerization, and then intermediate 1 was added and stirred to continue the chain extension reaction. After reacting for 25 minutes, the mixture was cooled and discharged to obtain polyurethane; wherein the mass ratio of polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and intermediate 1 was 1.6:1:0.015:0.6; (6) 8 parts by weight of modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, 30 parts by weight of polyurethane and 2 parts by weight of calcium carbonate are extruded into pellets at 185° C. in a twin-screw extruder, and the pellets are compression molded in a flat plate vulcanizer at a pressure of 8 MPa and at 190° C. to obtain a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol. Example 4
[0015] (1) 0.68 g of chitosan was dissolved in 1% acetic acid solution, and then 0.01 g of initiator 1-hydroxybenzotriazole monohydrate was added to react for 0.4 h, and then 0.3 g of (3-carboxypropyl) triphenylphosphonium bromide was added thereto, and nitrogen was introduced to protect the reaction at 70 °C for 12 h, and then 0.5 g of acrylic acid was added and the reaction was continued for 40 min. After the reaction, the solution was dialyzed for 2 days using a dialysis bag with a molecular weight cutoff of 3500 to obtain modified chitosan; (2) Adding modified chitosan to N,N-dimethylformamide solvent, stirring and dispersing, and then adding mercaptoethylamine and benzoin dimethyl ether photoinitiator, wherein the mass ratio of modified chitosan, mercaptoethylamine, and benzoin dimethyl ether photoinitiator is 1:1.2:0.01, irradiating with ultraviolet light at 20°C for h, centrifuging after irradiation, washing and drying to obtain intermediate 1; (3) adding intermediate 1 and 1,3-propane sultone to acetone solvent for dissolution, wherein the mass ratio of intermediate 1 to 1,3-propane sultone is 1.1:1, then adding dropwise a 5% sodium hydroxide solution, reacting at 85°C for 10 hours, and concentrating under reduced pressure to remove the solvent after the reaction, and the crude product is recrystallized in ethanol to obtain intermediate 2; (4) Adding intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol to N,N-dimethylformamide solvent, wherein the mass ratio of intermediate 2 to 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is 1:2.3, stirring and mixing, stirring and reacting at 110° C. for 8 h, and then distilling under reduced pressure and washing to obtain modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol; (5) After removing water from the polyether diol, the mixture was mixed evenly with hexamethylene diisocyanate, nitrogen was introduced, and then dibutyltin dilaurate catalyst was added dropwise, and the mixture was reacted at 70° C. for 3 hours for prepolymerization, and then intermediate 1 was added and stirred to continue the chain extension reaction. After reacting for 25 minutes, the mixture was cooled and discharged to obtain polyurethane; wherein the mass ratio of polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and intermediate 1 was 1.6:1:0.015:0.6; (6) 8 parts by weight of modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, 30 parts by weight of polyurethane and 2 parts by weight of calcium carbonate are extruded into pellets at 185° C. in a twin-screw extruder, and the pellets are compression molded in a flat plate vulcanizer at a pressure of 8 MPa and at 190° C. to obtain a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol.
[0016] Comparative Example 1 Compared with Example 4, this comparative example differs in that no modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is added.
[0017] A Staphylococcus aureus liquid with a concentration of 2×108 CFU / mL was added to a sterilized culture dish as a test strain, and then a solid agar medium was added and dissolved, cooled to 45°C, and then poured into the culture dish, 20 mL was poured into each plate with an inner diameter of 10 cm, and then the materials of the embodiments of the present invention and the comparative example (with a diameter of 3 cm and a thickness of 1 mm) were placed on the culture plate, and cultured in a constant temperature incubator for 12 hours at a temperature of 37°C. After culture, the diameter of the inhibition zone was measured. The test results are shown in Table 1.
[0018] Table 1: Antimicrobial testing.
[0019]
[0020] It can be seen from Table 1 that Examples 1-4 of the present invention have better antibacterial effects than Comparative Example 1.
[0021] Use an oxygen index meter to test the limiting oxygen index of the material; use a horizontal and vertical combustion instrument to test the combustion level of the material.
[0022] Table 2: Flame retardancy test.
[0023]
[0024] It can be seen from Table 2 that Examples 1-4 have better flame retardant effects than Comparative Example 1.
[0025] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.
Claims
1. A material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, characterized in that: The invention comprises the following components by weight: 5-10 parts by weight of modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, 25-40 parts by weight of polyurethane and 1-3 parts by weight of calcium carbonate.
2. The material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol according to claim 1, characterized in that The preparation method of the modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is as follows: (1) 0.68-0.71 g of chitosan was dissolved in 1% acetic acid solution, and then an initiator 1-hydroxybenzotriazole monohydrate was added to react for 0.4-0.6 h, and then 0.3-0.5 g of (3-carboxypropyl) triphenylphosphonium bromide was added thereto, and nitrogen was introduced for protection, and the reaction was carried out at 70-90 ° C for 12-14 h, and then 0.5-0.9 g of acrylic acid was added, and the reaction was continued for 40-50 min. After the reaction, the reaction was dialyzed with a dialysis bag with a molecular weight cutoff of 3500 for 2-3 days to obtain modified chitosan; (2) adding modified chitosan to N,N-dimethylformamide solvent, stirring and dispersing, then adding mercaptoethylamine and benzoin dimethyl ether photoinitiator, irradiating with ultraviolet light for 3-5 hours at 20-40° C., centrifuging, washing and drying to obtain intermediate 1; (3) adding intermediate 1 and 1,3-propane sultone to acetone solvent for dissolution, then dropping a 2-5% sodium hydroxide solution, reacting at 60-85° C. for 6-10 hours, concentrating under reduced pressure to remove the solvent, and recrystallizing the crude product in ethanol to obtain intermediate 2; (4) Add intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol to N,N-dimethylformamide solvent, stir and mix, and react at 90-110°C for 5-8 hours. After reaction, evaporate under reduced pressure and wash to obtain modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol.
3. The material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol according to claim 2, characterized in that: The mass of the initiator 1-hydroxybenzotriazole monohydrate in (1) is 0.01-0.02 g.
4. The material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol according to claim 2, characterized in that The mass ratio of the modified chitosan, mercaptoethylamine and benzoin dimethyl ether photoinitiator in (2) is 1:1.2-1.3:0.01-0.
02.
5. The material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol according to claim 2, characterized in that: The mass ratio of the intermediate 1 to 1,3-propane sultone in (3) is 0.6-1.1:
1.
6. The material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol according to claim 2, characterized in that: The mass ratio of the intermediate 2 and 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol in (4) is 1:2.1-2.
3.
7. The material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol according to claim 1, characterized in that: The preparation method of the polyurethane comprises the following steps: removing water from the polyether diol and mixing it evenly with hexamethylene diisocyanate, introducing nitrogen, then dropping a dibutyltin dilaurate catalyst, reacting at 50-80°C for 2-4h to perform prepolymerization, then adding an intermediate 1, stirring to continue a chain extension reaction, reacting for 20-30min, cooling, discharging, and obtaining the polyurethane; wherein the mass ratio of the polyether diol, the hexamethylene diisocyanate, the dibutyltin dilaurate catalyst, and the intermediate 1 is 1.2-2:1:0.01-0.02:0.4-0.
8.
8. A method for preparing a material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol as claimed in any one of claims 1 to 7, characterized in that: The preparation method of the material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol is as follows: modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol, polyurethane and calcium carbonate are extruded and granulated at 180-190° C. in a twin-screw extruder, and then the granules are molded in a flat vulcanizer at 185-190° C. under a pressure of 8-9 MPa to obtain the material containing modified 6-chloro-1H-pyrazolo[4,3-C]pyridine-alcohol.