CN112094407A - Biguanide group covalent organic framework material and preparation method and application thereof - Google Patents
Biguanide group covalent organic framework material and preparation method and application thereof Download PDFInfo
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- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
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- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
- C08G63/06—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from hydroxycarboxylic acids
- C08G63/08—Lactones or lactides
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- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
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- C08G63/823—Preparation processes characterised by the catalyst used for the preparation of polylactones or polylactides
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Abstract
The invention discloses a biguanide group covalent organic framework material and a preparation method and application thereof, wherein the biguanide group covalent organic framework material has a two-dimensional organic framework, and a specific biguanide structure can be directly used as a catalyst for direct polycondensation of lactic acid to polylactic acid and ring-opening polymerization of lactide body to polylactic acid. According to the invention, biguanide is introduced into the covalent organic framework material, so that excellent catalytic effects of direct polycondensation of lactic acid to polylactic acid and ring-opening polymerization of lactide bulk to polylactic acid are achieved, the polymerization degree of the polymer can be controlled and synthesized according to requirements, the molecular weight distribution index PDI is narrow, the catalyst and the product are easy to separate, no catalyst residue exists in the product, and the synthesized polylactic acid has high biological safety; meanwhile, the covalent organic framework material constructed by the biguanide can be repeatedly utilized, so that the application cost is greatly reduced, and the covalent organic framework material can be widely popularized and applied.
Description
Technical Field
The invention relates to a biguanide group covalent organic framework material and a preparation method and application thereof, belonging to the technical field of guanidine heterogeneous catalysts.
Background
With the rapid development of the biomedical field at home and abroad, the demand for a medical degradable material with excellent biocompatibility and safety is rapidly increased, and the medical degradable material can be particularly applied to drug carriers, tissue repair materials and the like. Polylactic acid has attracted a great deal of attention because of its good biocompatibility and degradability, and has many important applications in the field of biomedicine. Heretofore, the commercial production of polylactic acid is mainly synthesized by a stannous octoate ring-opening polymerization method, but a tin-containing catalyst cannot be completely removed from a polymer after the polymerization reaction. Therefore, it is necessary to develop a tin-free, non-toxic and easily separable catalyst.
Covalent Organic framework materials (COFs) are porous compounds with a periodic structure linked by Covalent bonds from Organic building blocks. In stark contrast to covalent polymers attached by irreversible condensation, COFs exhibit a highly ordered crystal structure by reversible reactions. In contrast to conventional crystalline porous solids, such as zeolites and Metal Organic Frameworks (MOFs), COFs have precisely predefinable structures and tailored functions, allowing structural and chemical control of the function. Different compositions, porosities, pore sizes and the like can be designed according to requirements to achieve specific purposes.
In general, methods for synthesizing COFs include solvothermal methods, ionothermal methods, microwave irradiation methods, mechanical milling methods, and the like. The most common preparation method of COFs is a solvothermal method, i.e. reaction monomers, solvents and catalysts are added into a system, and reaction is carried out after oxygen is removed through freeze-pumping circulation operation, and in a closed reaction system, through controlling the types of solvents, the proportion of solvents or the reaction pressure, a thermodynamically stable product is generated in a relatively slow process. The traditional homogeneous catalysis has many defects, such as difficult separation of reaction products and catalysts, difficult reuse of the catalysts and great waste, and the like, and the use of the COFs catalysts can effectively solve the problems. Because the structure of COFs is stable and insoluble in solvent, it can be used as a nano-reactor in a small space. After the reaction is finished, the product can be easily separated from the reaction mixture and can be repeatedly used.
Guanidine, a nitrogen-containing organic compound, is a strong organic base with a basicity comparable to that of strong inorganic bases and a basicity similar to that of sodium hydroxide, and the presence of a wide variety of guanidine catalysts (bicyclic, monocyclic and acyclic) allows many of the basic organic transformations to be achieved efficiently. However, guanidine compounds are more polar, which makes separation and purification difficult and also imposes more restrictions on the synthesis method. Therefore, the guanidine compound is introduced into the covalent organic framework material to be used as a heterogeneous catalyst, can be recycled simply and greatly reduces the purification cost and the production cost. In the modification of biguanide, it has been previously reported that metformin is immobilized on SiO by introducing it into a functional guanidine ionic liquid2And the like, but the overall catalytic recovery efficiency is not high. In addition, guanidine is also applied to the research of synthesizing polylactic acid, for example, the invention of Chinese patent publication No. CN 102875779B reports a process method for synthesizing medical biodegradable polylactic acid by catalyzing polycondensation of lactic acid with bicyclic guanidine, and for example, the invention of Chinese patent publication No. CN 104892916B reports a process for synthesizing polylactic acid by controlling the activity ring-opening polymerization of lactide catalyzed by organic guanidine-nontoxic alcohol, but the processes still do not ideally improve the catalytic efficiency and the recycling rate. Therefore, the heterogeneous catalyst of the novel guanidine compound is synthesized by combining the advantages of the covalent organic framework material, and the good catalytic activity of recycling is achieved, so that the heterogeneous catalyst still has great research and utilization values.
Disclosure of Invention
The invention aims to solve the problem that the existing guanidine catalyst is limited in application of catalyzing direct polycondensation of lactic acid into polylactic acid and ring-opening polymerization of lactide body into polylactic acid due to difficult synthesis and complicated separation and purification of guanidine compounds. According to the invention, biguanide is introduced into the covalent organic framework material, so that excellent catalytic effects of direct polycondensation of lactic acid to polylactic acid and ring-opening polymerization of lactide bulk to polylactic acid are achieved, the polymerization degree of the polymer can be controlled and synthesized according to requirements, the molecular weight distribution index PDI is narrow, the catalyst and the product are easy to separate, no catalyst residue exists in the product, and the synthesized polylactic acid has high biological safety; meanwhile, the covalent organic framework material constructed by the biguanide can be recycled, so that the application cost is greatly reduced.
In order to achieve the purpose, the invention adopts the following technical scheme:
the first aspect of the invention provides a biguanide group covalent organic framework material, which is abbreviated as COF-JNU, and has a characteristic structure shown in formula 1:
in the formula 1, ` L `1' is
Structure; "L2' is
One of the structures.
In a second aspect of the invention, there is provided a process for preparing a biguanide-based covalent organic framework material COF-JNU, comprising the steps of: aromatic amine and 1, 4-benzene dicyandiamide or sodium dicyandiamide react for 24-48 h in water or an organic solvent by using hydrochloric acid as a catalyst at the molar ratio of 2:3 under the protection of nitrogen at the temperature of 90-100 ℃, and the biguanide group covalent organic framework material COF-JNU is obtained after the reaction is finished and is subjected to centrifugation, washing and drying.
Further, the aromatic amine is one of melamine, 1,3, 5-triaminobenzene, 2,4, 6-tris (4-aminophenyl) -1,3, 5-triazine or 1,3, 5-tris (4-aminophenyl) benzene.
Further, the organic solvent is one or more of dimethyl sulfoxide, N-dimethylformamide and dioxane which are mixed for use.
Furthermore, the addition amount of the hydrochloric acid is 2-3 times of the equivalent of the aromatic amine.
The third aspect of the invention provides an application of biguanide group covalent organic framework material COF-JNU in direct polycondensation of lactic acid to polylactic acid, wherein the biguanide group covalent organic framework material COF-JNU is added into a reaction system in two steps to perform catalytic reaction, and the catalytic reaction equation is shown as the following formula 2:
wherein the first step of reaction is the synthesis of OLLA, namely, the L-lactic acid and COF-JNU (the mass of the L-lactic acid is 0.5%) with predetermined amounts are placed in a 30torr sealed reaction kettle under the protection of nitrogen, and the reaction is carried out for 2-3 h at 135 ℃ to obtain a viscous liquid mixture of OLLA; and the second step of reaction is the synthesis of polylactic acid PLLA, namely, continuously heating the viscous liquid mixture of the OLLA prepared in the first step to 175 ℃, simultaneously reducing the pressure in the reaction kettle to 10torr, reacting for 0.5-4 h, cooling to room temperature after the reaction is finished, dissolving the reaction liquid in acetone, filtering and recovering a catalyst COF-JNU, pouring the filtrate into water, standing, centrifugally separating precipitates, and drying in vacuum at room temperature to obtain a white solid, namely the polylactic acid PLLA. The yield of the catalytic reaction for directly condensing lactic acid into polylactic acid by adopting the biguanide group covalent organic framework material COF-JNU is more than 94 percent, and the range of Mn is 1 x 104～4.5×104And PDI is 1.10-1.30.
The fourth aspect of the invention provides an application of biguanide group covalent organic framework material COF-JNU in the lactide bulk ring-opening polymerization to polylactic acid, wherein the biguanide group covalent organic framework material COF-JNU is directly added into a reaction system for lactide bulk ring-opening polymerization to polylactic acid to perform catalytic reaction, and the catalytic reaction equation is shown as the following formula 3:
the method comprises the following specific steps: and (2) placing a monomer L-lactide and COF-JNU (accounting for 0.5% of the mass of the L-lactide) in a reaction kettle under the protection of nitrogen, reacting for 0.5-4 h at 130 ℃, cooling to room temperature after the reaction is finished, dissolving the reaction solution in acetone, filtering to recover a catalyst COF-JNU, pouring the filtrate into water, standing, centrifugally separating precipitates, and drying in vacuum at room temperature to obtain a white solid, namely the polylactic acid PLLA. The yield of the catalytic reaction of the biguanide group covalent organic framework material COF-JNU for the ring-opening polymerization of lactide into polylactic acid is more than 95%, and the range of Mn is 1 x 104～5×104And PDI is 1.10-1.30.
Further, the covalent organic framework material COF-JNU constructed by biguanide can be used for the next round of heterogeneous catalytic reaction after the reaction liquid is filtered after being simply treated after catalyzing direct polycondensation of lactic acid to polylactic acid and the ring-opening polymerization of lactide body to polylactic acid, and the catalyst can be recovered after being washed and dried.
Compared with the prior art, the invention has the advantages and beneficial effects that:
(1) the biguanide group covalent organic framework material COF-JNU has better thermal stability, catalytic activity and recycling performance;
(2) the biguanide group covalent organic framework material COF-JNU can be prepared under the condition of various single or mixed solvents, and the synthetic method has universality, simple synthetic method and controllable structure;
(3) the biguanide group covalent organic framework material COF-JNU has high catalytic efficiency in the application of catalyzing direct polycondensation of lactic acid to polylactic acid and ring-opening polymerization of lactide body to polylactic acid, the polymerization degree of the polymer can be controlled and synthesized according to the requirement, and the molecular weight distribution index PDI is narrow;
(4) the biguanide group covalent organic framework material COF-JNU is easy to separate catalyst from product in the application of catalyzing direct polycondensation of lactic acid to polylactic acid and ring-opening polymerization of lactide body to polylactic acid, and the product has no catalyst residue, and the synthesized polylactic acid has high biological safety.
Drawings
FIG. 1 is an infrared spectrum of COF-JNU-01 of example 1 of the present invention;
FIG. 2 is a transmission electron micrograph of COF-JNU-01 of example 1 of the present invention at 200 nm;
FIG. 3 is a transmission electron micrograph of COF-JNU-01 at 500nm of example 1 of the present invention;
FIG. 4 is a thermogravimetric analysis diagram of COF-JNU-01 of example 1 of the present invention;
FIG. 5 is a nitrogen adsorption-desorption graph of COF-JNU-01 of example 1 of the present invention.
Detailed Description
The present invention is further illustrated by the following figures and preferred examples, which are carried out on the premise of the technical scheme of the present invention, and detailed embodiments and processes are given, but the scope of the present invention is not limited to the following examples, and the experimental methods without specific conditions noted in the following examples are generally performed according to conventional conditions or conditions recommended by manufacturers.
The reagents used in the examples of the invention and the comparative examples are shown in table 1 below, but are not limited thereto:
TABLE 1
| Name of reagent | Molecular formula | CAS number | Suppliers of goods | Purity of |
| Dicyandiamide sodium salt | C2N3Na | 1934-75-4 | SHANGHAI ALADDIN BIOCHEMICAL TECHNOLOGY Co.,Ltd. | 96％ |
| Hydrochloric acid (aqueous HCl) | / | 7647-01-0 | SINOPHARM CHEMICAL REAGENT Co.,Ltd. | 36～38％ |
| Ethanol | C2H6O | 64-17-5 | SHANGHAI TITAN TECHNOLOGY Co.,Ltd. | 99.5％ |
| Melamine | C3H6N6 | 108-78-1 | SHANGHAI TITAN TECHNOLOGY Co.,Ltd. | 99％ |
| P-phenylenediamine | C6H8N2 | 106-50-3 | SHANGHAI ALADDIN BIOCHEMICAL TECHNOLOGY Co.,Ltd. | 99％ |
| 4-aminoacetophenones | C8H9NO | 99-92-3 | SHANGHAI TITAN TECHNOLOGY Co.,Ltd. | 99％ |
| P-toluenesulfonic acid monohydrate | TsOH·H2O | 6192-52-5 | SINOPHARM CHEMICAL REAGENT Co.,Ltd. | 99％ |
| Ethyl acetate | C4H8O2 | 141-78-6 | SHANGHAI TITAN TECHNOLOGY Co.,Ltd. | 99.5％ |
| Anhydrous sodium sulfate | Na2SO4 | 15124-09-1 | SINOPHARM CHEMICAL REAGENT Co.,Ltd. | 98％ |
| Nitrogen gas | N2 | 7727-37-9 | Taihu gas Co Ltd of Wuxi City | 99.2％ |
| 4-aminobenzonitrile | C7H6N2 | 873-74-5 | SHANGHAI ALADDIN BIOCHEMICAL TECHNOLOGY Co.,Ltd. | 98％ |
| 1,3, 5-triaminobenzene | C6H9N3 | 108-72-5 | BIDE PHARMATECH Ltd. | 95％ |
| Chloroform | CHCl3 | 67-66-3 | SINOPHARM CHEMICAL REAGENT Co.,Ltd. | 99.7％ |
| Trifluoromethanesulfonic acid | CF3SO3H | 1493-13-6 | SHANGHAI TITAN TECHNOLOGY Co.,Ltd. | 99％ |
| Sodium hydroxide | NaOH | 1310-73-2 | Chemical test of national medicine groupAgents Ltd | 97％ |
| L-lactic acid | C3H6O3 | 79-33-4 | BIDE PHARMATECH Ltd. | 95％ |
| Acetone (II) | C3H6O | 67-64-1 | SINOPHARM CHEMICAL REAGENT Co.,Ltd. | 99.5％ |
| L-lactide | C6H8O4 | 4511-42-6 | BIDE PHARMATECH Ltd. | 99％ |
Example 1
A method for preparing a biguanide-based covalent organic framework material (COF-JNU-01), comprising the steps of:
melamine (0.42g,0.33mmol), dicyandiamide sodium (0.045g,0.5mmol) and 20mL of water are weighed into a Schlenk tube, and an HCl aqueous solution (0.08mL) is added dropwise while stirring, and after the addition is finished, the reaction is carried out for 36h at 100 ℃ under the protection of nitrogen. After the reaction is finished, standing overnight, centrifuging, and washing with ethanol and water for three times respectively. After vacuum drying, yellow powder, namely the covalent organic framework material COF-JNU-01, can be obtained.
The present invention characterizes the above synthetic biguanide-based covalent organic framework material COF-JNU-01.
Wherein, FIG. 1 shows an infrared spectrogram of COF-JNU-01, which indicates the successful synthesis of COF-JNU-01.
FIG. 2 and FIG. 3 are transmission electron microscope images of COF-JNU-01 with scales of 200nm and 500nm, respectively, which show that the COF-JNU-01 is in a flake shape and is a micron-sized organic framework material, and forms a larger specific surface area, thereby being beneficial to improving catalytic reaction activity.
FIG. 4 is a thermogravimetric analysis diagram of COF-JNU-01, which shows that COF-JNU-01 has better thermal stability, thereby ensuring that the heterogeneous catalyst of the present invention has good stability during the application process.
FIG. 5 is a nitrogen adsorption-desorption graph of COF-JNU-01, which shows that COF-JNU-01 has a higher specific surface area.
Example 2
A method for preparing a biguanide-based covalent organic framework material (COF-JNU-02), comprising the steps of:
(1) synthesis of monomeric 1, 4-benzenedicyandiamide
P-phenylenediamine (1.30g,12mmol) was weighed into a boiling water solution of sodium dicyandiamide (0.49g,5.5mmol), stirred for 10 minutes, added with 1M aqueous HCl (25mL), and refluxed for 3 hours. After the reaction is finished, the solvent is removed by spinning, the residue is treated by hot ethanol, and the mixture is filtered while the residue is hot to obtain light gray solid, namely the monomer 1, 4-benzenedicyandiamide.
(2) Synthesis of monomer 1,3, 5-tri (4-aminophenyl) benzene
Weighing 4-amino acetophenone (2.7g,20mmol), adding into a reaction flask, heating to 130 deg.C, gradually melting, and adding TsOH & H in batches2O (0.54g,0.15eq), and then heated to 145 ℃ for reaction for 16 h. After the reaction, ethyl acetate was added to dissolve the reaction product, and water was added to extract the product. Adding anhydrous sodium sulfate into the organic phase, drying, and performing column chromatography to obtain yellow powder, namely the monomer 1,3, 5-tri (4-aminophenyl) benzene.
(3) Synthesis of covalent organic framework materials COF-JNU-02
Monomers of 1,3, 5-tri (4-aminophenyl) benzene (0.117g,0.33mol), 1, 4-benzenedicyandiamide (0.121g,0.5mmol) and 20mL of water are weighed and added into a Schlenk tube, an HCl aqueous solution (0.08mL) is added dropwise when stirring is carried out, and after the dropwise addition is finished, the reaction is carried out for 36 hours at 100 ℃ under the protection of nitrogen. After the reaction is finished, standing overnight, centrifuging, and washing with ethanol and water for three times respectively. After vacuum drying, yellow powder, namely the covalent organic framework material COF-JNU-02, can be obtained.
Example 3
A method for preparing a biguanide-based covalent organic framework material (COF-JNU-03), comprising the steps of:
(1) synthesis of monomer 2,4, 6-tri (4-aminophenyl) -1,3, 5-triazine
Weighing 4-aminobenzonitrile (3.08g,26mmol), adding into a reaction bottle, adding 20mL of chloroform as a solvent, dropwise adding trifluoromethanesulfonic acid (8mL,88.8mmol) very slowly in an ice bath, wherein the reaction solution becomes viscous when dropwise adding, and after dropwise adding, carrying out nitrogen protection. After stirring for 1 hour, the mixture was allowed to warm to room temperature and stirred for 24 hours. After the reaction is finished, 40mL of distilled water is measured and added into the reaction solution, then 2M NaOH solution is slowly added to adjust the pH of the filtrate to be neutral, the reaction solution is changed from viscous to yellow solid to be separated out, and a crude product can be obtained by suction filtration. The crude product is washed by distilled water for five times, and light yellow powder is obtained by column chromatography, namely the monomer 2,4, 6-tri (4-aminophenyl) -1,3, 5-triazine.
(2) Synthesis of covalent organic framework materials COF-JNU-03
2,4, 6-tris (4-aminophenyl) -1,3, 5-triazine (0.118g,0.33mmol), sodium dicyandiamide (0.045g,0,5mmol) and 20mL of water are weighed and added into a Schlenk tube, an aqueous HCl solution (0.08mL) is added dropwise while stirring, and after the dropwise addition is completed, the reaction is carried out for 36h at 100 ℃ under the protection of nitrogen. After the reaction is finished, standing overnight, centrifuging, and washing with ethanol and water for three times respectively. After vacuum drying, yellow powder, namely the covalent organic framework material COF-JNU-03, can be obtained.
Example 4
A preparation method of biguanide group covalent organic framework material COF-JNU-04 comprises the following steps:
weighing 1,3, 5-triaminobenzene (0.41g,0.33mmol), 1, 4-benzenedicyandiamide (0.121g,0.5mmol (the preparation method is the same as the step (1) of the example 2)) and 20mL of water, adding into a Schlenk tube, dropwise adding HCl aqueous solution (0.08mL) while stirring, reacting at 100 ℃ for 36h under the protection of nitrogen after dropwise adding, standing overnight after the reaction is finished, centrifuging, washing with ethanol and water for three times respectively, and drying in vacuum to obtain yellow powder, namely the covalent organic framework material COF-JNU-04.
The products obtained in examples 2 to 4 were subjected to infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis and nitrogen adsorption-desorption measurement in the same manner as in example 1, and similar technical effects to those of example 1 were obtained, and the products also had good dispersibility, a high specific surface area and excellent thermal stability.
Example 5
The biguanide group covalent organic framework material COF-JNU shows excellent catalytic activity and performance convenient for separation and recovery in the application of catalyzing direct polycondensation of lactic acid to polylactic acid. The application of the biguanide-based covalent organic framework material COF-JNU-01 synthesized in example 1 in catalyzing the direct polycondensation of lactic acid to polylactic acid is illustrated as follows.
(1) Synthesis of OLLA
L-lactic acid (2g) and COF-JNU-01(0.1g) were weighed and placed in a 30torr sealed reaction vessel under nitrogen protection, and reacted at 135 ℃ for 2 hours to obtain a viscous liquid mixture of OLLA.
(2) Synthesis of polylactic acid PLLA
And (2) continuously heating the viscous liquid mixture of the oligomeric lactic acid OLLA obtained in the step (1) to 175 ℃, simultaneously gradually reducing the pressure in the reaction kettle to 10torr, reacting for 2 hours, and cooling to room temperature after the reaction is finished. Dissolving the reaction liquid in acetone, filtering to recover the catalyst COF-JNU-01 in the filter cake for the next circulation catalysis, pouring the filtrate into water, standing, centrifugally separating the precipitate, vacuum drying at room temperature for 36 hours to obtain white solid, namely polylactic acid PLLA, with the yield of 95.1 percent and the Mn of 2.1 × 104，PDI＝1.12。
Example 6
The biguanide group covalent organic framework material COF-JNU shows excellent catalytic activity and performance of facilitating separation and recovery in the application of catalyzing the ring-opening polymerization of lactide into polylactic acid. The application of the biguanide-based covalent organic framework material COF-JNU-01 synthesized in example 1 in catalyzing the ring-opening polymerization of lactide into polylactic acid is illustrated as follows.
The monomer L-lactide (1g) and COF-JNU-01(0.05g) are placed in a reaction kettle under the protection of nitrogen, the reaction is carried out for 3h at 130 ℃, and the reaction is cooled to room temperature after the reaction is finished. Dissolving the reaction liquid in acetone, filtering to recover the catalyst COF-JNU-01 in the filter cake for the next circulation catalysis, pouring the filtrate into water, standing, centrifugally separating the precipitate, and vacuum drying at room temperature to obtain white solid, i.e. polylactic acid PLLA, with the yield of 96.2% and Mn of 3.2 × 104，PDI＝1.13。
Comparative example 1
The preparation of polylactic acid PLLA by using bicyclic guanidine as a catalyst, referring to the method provided in example 2 of the invention patent "technological method for synthesizing medical biodegradable polylactic acid by polycondensation of lactic acid catalyzed by bicyclic guanidine" of patent publication No. CN 102875779B, comprises the following steps:
80g of L-lactic acid (90% by mass) was charged into the reaction vessel, and the operation of vacuumizing and filling argon was repeated three times. Heating to 110 ℃ at 200torr, and carrying out dehydration reaction for 1 h. The autoclave was then depressurized to 100torr and the reaction was continued for 1h at 130 ℃. Then, the reaction kettle is decompressed to 30torr and continuously reacted for 1 hour at 150 ℃, and the oligomeric lactic acid OLLA is obtained.
Adding 240mg of catalyst bicyclic guanidine into the reaction kettle, decompressing the reaction kettle to 10torr, and heating to 190 ℃ for reaction for 16 hours. After the reaction was stopped, the reaction kettle was cooled to room temperature, the polymer was dissolved in acetone, then poured into 0 ℃ ethanol, filtered under reduced pressure, and the solid was dried at 50 ℃ under vacuum for 36 hours to give a white solid, i.e., polylactic acid PLLA, with a yield of 73.1%, Mn 2.3 × 10 ═4，PDI＝1.70。
Comparative example 2
The method for preparing the polylactic acid PLLA by taking guanine acetate as a catalyst and ethanol as an initiator according to the method provided by the embodiment 4 in the invention patent of patent publication No. CN 104892916B, namely the process for synthesizing the polylactic acid by catalyzing the activity of lactide through ring-opening polymerization in a controlled manner, comprises the following specific steps:
adding 100g of monomer LLA, 0.098g of catalyst guanine acetate and 0.230g of initiator ethanol into a polymerization kettle, and removing the polymerization kettle by three times of 'vacuumizing-nitrogen exchanging' circulation operationAir in the reactor, sealing the reactor after the pressure in the reactor is constant at 0.6torr, heating to 96 ℃ within 30min while stirring, and then reacting at 115 +/-1 ℃ for 80min to obtain a white solid, namely polylactic acid PLLA, wherein the yield is 83.7%, and the Mn is 2.0 multiplied by 104，PDI＝1.18。
By comparing the yield, Mn and PDI values of the polylactic acid PLLA prepared by the methods of comparative example 1 and example 5, and comparative example 2 and example 6, it can be seen that the catalytic activity is better with the biguanide-based covalent organic framework material COF-JNU of the present invention, the degree of polymerization of the polymer can be controlled and synthesized according to the need, the molecular weight distribution index PDI is narrower, and in addition, the biguanide-based covalent organic framework material COF-JNU of the present invention is easily separated from the product, and the product has no catalyst residue, and the synthesized polylactic acid has high bio-safety.
The above description is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto. All equivalent changes, simplifications and modifications which do not depart from the spirit and scope of the invention are intended to be covered by the scope of the invention.
Claims (10)
1. The biguanide-based covalent organic framework material is characterized in that the biguanide-based covalent organic framework material COF-JNU has a characteristic structure shown in formula 1:
in the formula 1, ` L `1' is
Structure; "L2' is
One of the structures.
2. The method of claim 1, comprising the steps of: aromatic amine and 1, 4-benzene dicyandiamide or sodium dicyandiamide react for 24-48 h in water or an organic solvent by using hydrochloric acid as a catalyst at the molar ratio of 2:3 under the protection of nitrogen at the temperature of 90-100 ℃, and the biguanide group covalent organic framework material COF-JNU is obtained after the reaction is finished and is subjected to centrifugation, washing and drying.
3. The method of claim 2, wherein the aromatic amine is one of melamine, 1,3, 5-triaminobenzene, 2,4, 6-tris (4-aminophenyl) -1,3, 5-triazine, or 1,3, 5-tris (4-aminophenyl) benzene.
4. The method for preparing a biguanide-based covalent organic framework material according to claim 2, wherein the organic solvent is one or more of dimethylsulfoxide, N-dimethylformamide and dioxane.
5. The method of claim 2, wherein the amount of hydrochloric acid added is 2 to 3 equivalents of the aromatic amine.
6. The use of a biguanide-based covalent organic framework material according to claim 1 in the direct polycondensation of lactic acid to polylactic acid.
7. The use of biguanide-based covalent organic framework material according to claim 6 in the direct polycondensation of lactic acid to polylactic acid, wherein the biguanide-based covalent organic framework material COF-JNU is added to the reaction system in two steps to perform a catalytic reaction, and the catalytic reaction equation is shown in the following formula 2:
wherein, the first step of reaction is the synthesis of OLLA; the second step reaction is the synthesis of polylactic acid PLLA.
8. The use of a biguanide-based covalent organic framework material according to claim 7 in the direct polycondensation of lactic acid to polylactic acid, wherein said first reaction step comprises: putting predetermined amounts of L-lactic acid and COF-JNU (0.5% relative to the mass of the L-lactic acid) into a 30torr sealed reaction kettle under the protection of nitrogen, and reacting for 2-3 h at 135 ℃ to obtain a viscous liquid mixture of the oligomeric lactic acid OLLA; the second reaction step comprises: and (2) continuously heating the viscous liquid mixture of the OLLA prepared in the first step to 175 ℃, simultaneously reducing the pressure in the reaction kettle to 10torr, reacting for 0.5-4 h, cooling to room temperature after the reaction is finished, dissolving the reaction liquid in acetone, filtering and recovering a catalyst COF-JNU, pouring the filtrate into water, standing, centrifugally separating precipitates, and performing vacuum drying at room temperature to obtain a white solid, namely the PLLA.
9. Use of a biguanide based covalent organic framework material according to claim 1 in the bulk ring opening polymerization of lactide into polylactic acid.
10. The use of biguanide-based covalent organic framework material according to claim 9 in the bulk ring-opening polymerization of lactide into polylactic acid, wherein the biguanide-based covalent organic framework material COF-JNU is directly added into the reaction system for the bulk ring-opening polymerization of lactide into polylactic acid for catalytic reaction, and the catalytic reaction equation is shown in the following formula 3:
the method comprises the following specific steps: and (2) placing a monomer L-lactide and COF-JNU (accounting for 0.5% of the mass of the L-lactide) in a reaction kettle under the protection of nitrogen, reacting for 0.5-4 h at 130 ℃, cooling to room temperature after the reaction is finished, dissolving the reaction solution in acetone, filtering to recover a catalyst COF-JNU, pouring the filtrate into water, standing, centrifugally separating precipitates, and drying in vacuum at room temperature to obtain a white solid, namely the polylactic acid PLLA.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113304261A (en) * | 2021-05-28 | 2021-08-27 | 江南大学 | Construction and application of charge reversal type intelligent light diagnosis and treatment platform |
| CN113788937A (en) * | 2021-09-15 | 2021-12-14 | 青岛科技大学 | Synthetic method of crystalline porous polymer material confined catalytic lactide |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08291152A (en) * | 1995-04-24 | 1996-11-05 | Taiyo Ink Mfg Ltd | Cyanoguanidine derivative and thermosetting or photosetting-thermosetting resin composition using the same |
| CN101641394A (en) * | 2007-03-12 | 2010-02-03 | 巴斯夫欧洲公司 | Preparation is based on the method for the product of cyclic organic carbonates |
| CN102875779A (en) * | 2012-10-16 | 2013-01-16 | 南京大学 | Process method for synthesizing medical biodegradable polylactic acid by performing polycondensation on lactic acid through catalysis of 1,5,7-triazabicyclo[4.4.0]decane-5-ene (TBD) |
| CN104892916A (en) * | 2015-06-11 | 2015-09-09 | 南京大学 | Technology for controlled synthesis of polylactic acid through lactide activity ring-opening polymerization under catalytic action of organic guanidine-nontoxic alcohol |
| CN105093866A (en) * | 2014-05-16 | 2015-11-25 | 佳能株式会社 | Electrophotographic member, process cartridge, and electrophotographic apparatus |
| CN107129583A (en) * | 2017-05-25 | 2017-09-05 | 西北师范大学 | The synthetic method of porous organic covalent frame material with triazine structure |
| CN110121548A (en) * | 2017-01-03 | 2019-08-13 | 陈煌兴 | Branched polymeric biguanide compound and application thereof |
| CN110240705A (en) * | 2019-05-10 | 2019-09-17 | 山东省分析测试中心 | A kind of preparation method and applications of richness nitrogen covalent organic framework material |
| CN111333836A (en) * | 2020-03-12 | 2020-06-26 | 江苏科技大学 | Porous covalent organic polymer based on melamine, preparation method and application thereof |
-
2020
- 2020-09-27 CN CN202011031835.5A patent/CN112094407B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08291152A (en) * | 1995-04-24 | 1996-11-05 | Taiyo Ink Mfg Ltd | Cyanoguanidine derivative and thermosetting or photosetting-thermosetting resin composition using the same |
| CN101641394A (en) * | 2007-03-12 | 2010-02-03 | 巴斯夫欧洲公司 | Preparation is based on the method for the product of cyclic organic carbonates |
| CN102875779A (en) * | 2012-10-16 | 2013-01-16 | 南京大学 | Process method for synthesizing medical biodegradable polylactic acid by performing polycondensation on lactic acid through catalysis of 1,5,7-triazabicyclo[4.4.0]decane-5-ene (TBD) |
| CN105093866A (en) * | 2014-05-16 | 2015-11-25 | 佳能株式会社 | Electrophotographic member, process cartridge, and electrophotographic apparatus |
| CN104892916A (en) * | 2015-06-11 | 2015-09-09 | 南京大学 | Technology for controlled synthesis of polylactic acid through lactide activity ring-opening polymerization under catalytic action of organic guanidine-nontoxic alcohol |
| CN110121548A (en) * | 2017-01-03 | 2019-08-13 | 陈煌兴 | Branched polymeric biguanide compound and application thereof |
| CN107129583A (en) * | 2017-05-25 | 2017-09-05 | 西北师范大学 | The synthetic method of porous organic covalent frame material with triazine structure |
| CN110240705A (en) * | 2019-05-10 | 2019-09-17 | 山东省分析测试中心 | A kind of preparation method and applications of richness nitrogen covalent organic framework material |
| CN111333836A (en) * | 2020-03-12 | 2020-06-26 | 江苏科技大学 | Porous covalent organic polymer based on melamine, preparation method and application thereof |
Non-Patent Citations (1)
| Title |
|---|
| BIN LUO ET AL.: "Design of guanidyl-functionalized magnetic covalent organic framework for highly selective capture of endogenous phosphopeptides", 《JOURNAL OF CHROMATOGRAPHY B》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113304261A (en) * | 2021-05-28 | 2021-08-27 | 江南大学 | Construction and application of charge reversal type intelligent light diagnosis and treatment platform |
| CN113788937A (en) * | 2021-09-15 | 2021-12-14 | 青岛科技大学 | Synthetic method of crystalline porous polymer material confined catalytic lactide |
| CN113788937B (en) * | 2021-09-15 | 2023-07-04 | 青岛科技大学 | Synthesis method of lactide catalyzed by crystalline porous polymer material in limited area |
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