CN112694611A - Method for catalytically synthesizing furyl polyamide under normal pressure - Google Patents
Method for catalytically synthesizing furyl polyamide under normal pressure Download PDFInfo
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- CN112694611A CN112694611A CN202011527461.6A CN202011527461A CN112694611A CN 112694611 A CN112694611 A CN 112694611A CN 202011527461 A CN202011527461 A CN 202011527461A CN 112694611 A CN112694611 A CN 112694611A
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- C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
- C08G69/40—Polyamides containing oxygen in the form of ether groups
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Abstract
The invention discloses a method for catalytically synthesizing furan-based polyamide under normal pressure, which relates to the technical field of polyamide synthesis, and adopts benzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate as a catalyst to replace an inorganic metal salt catalyst commonly used in the prior art, so that the problem that the thermodynamic property and the mechanical property of the prepared polymer are adversely affected due to catalyst residue can be solved, the furan-based polyamide polymer can be prepared by utilizing the catalyst through a simple reaction process at normal temperature and normal pressure, and the prepared furan-based polyamide polymer can be applied to the fields of preparing fibers, membrane materials, nano particle/polymer composite materials and the like.
Description
The technical field is as follows:
the invention relates to the technical field of polyamide synthesis, in particular to a method for catalytically synthesizing furyl polyamide under normal pressure.
Background art:
at present, the bio-based polymer materials widely used mainly include polylactic acid (PLA), Polyhydroxyalkanoate (PHA), polyglycolic acid (PGA), polybutylene succinate (PBS), and the like. They all belong to aliphatic polymers, and because of lack of rigid aromatic ring structure in the molecular structure, the mechanical properties (such as strength, modulus, creep resistance and the like) and heat resistance (such as thermal mechanical properties, thermal deformation temperature and the like) of the aliphatic polymers are obviously lower than petroleum-based high polymer materials such as polyethylene terephthalate (PET), Polycarbonate (PC), aromatic nylon (PA), bisphenol A type Epoxy resin (Epoxy) and the like, and the application range of the aliphatic polymers is severely limited.
The molecular structure of the 2, 5-furandicarboxylic acid (2,5-FDCA) contains aromatic rings, so that the heat resistance and the mechanical property of the synthetic bio-based polymer material can be effectively improved, and the oxygen barrier property of the polyester material containing the furan rings can be improved by 5-10 times compared with that of a large amount of PET used for packaging materials, so that the quality guarantee period of agricultural products, fish products and meat products can be effectively prolonged.
Compared with petroleum-based polyamide, the monomer 2, 5-furandicarboxylic acid of furan-based polyamide is prepared from biomass from renewable resources, and the emission of CO2 gas is remarkably reduced compared with petroleum-based raw materials, so that the environment-friendly degree is greatly improved, and the compound is also one of twelve most potential bio-based platform compounds screened by the U.S. department of energy. From the viewpoint of structural properties, furandicarboxylic acid is a five-membered aromatic ring, the structure is similar to that of thermal properties terephthalic acid, but since the furan ring has oxygen atoms, intermolecular hydrogen bonding force is reduced, van der waals force is enhanced, and thus solubility and processability are significantly enhanced. In addition, the introduction of oxygen atoms greatly enhances the coloring performance of the furan-based polyamide, which is particularly beneficial to the application in the field of fibers, and the characteristics enable the furan-based polyamide to have excellent development potential and application prospect.
CN104245793A discloses compositions and articles made therefrom relating to furan group meta-aramid and methods of making the same. Among the basic monomers used to obtain furan-based polyamide polymers are furandicarboxylic acid or its derivatives and m-phenylenediamine, which requires the use of inorganic metal salts such as LiCl as catalysts. Whereas inorganic metal salts such as LiCl are difficult to completely remove in the reaction system, the remaining inorganic salts may degrade the mechanical properties and mechanical system properties of the polyamide product.
Therefore, there is a need in the art for a simple synthesis method that avoids the use of conventional hazardous inorganic salt catalysts for the synthesis of furan-based polyamide polymers.
The invention content is as follows:
the technical problem to be solved by the invention is to provide a method for catalytically synthesizing furan-based polyamide under normal pressure, benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is used as a catalyst, and furan-based polyamide is prepared from diamine and furan diacid monomer.
The technical problem to be solved by the invention is realized by adopting the following technical scheme:
a method for catalytically synthesizing furan-based polyamide under normal pressure comprises the steps of adding furan-2, 5-dicarboxylic acid into a propane diamine solution at the temperature of-10-40 ℃ under the normal pressure condition, adding benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate, stirring the obtained mixture for reaction under the protection of inert gas, and separating a product after the reaction is finished to obtain the furan-based polyamide.
The propane diamine solution is obtained by dissolving propane diamine in an organic solvent.
The organic solvent is at least one of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone and acetonitrile.
The mass ratio of the organic solvent to the propane diamine is (1:1) - (10:1), preferably 5: 1.
The molar ratio of furan-2, 5-dicarboxylic acid to propylenediamine is (1:1) to (1:10), preferably 1: 1.
The molar ratio of the benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate to the furan-2, 5-dicarboxylic acid is (2:1) - (12: 1).
The reaction time is 1-24h, preferably 5 h.
The separation is performed by chromatography or chromatography.
The propane diamine can be replaced by p-phenylenediamine, m-phenylenediamine, ethylenediamine, 1, 4-butanediamine, 2, 3-diaminotoluene or 4, 4-diaminodiphenylmethane.
The furan-2, 5-dicarboxylic acid may be replaced with a furan-2, 5-dicarboxylic acid derivative.
The specific structural formula of the furan-2, 5-dicarboxylic acid derivative is as follows:
wherein R is1、R2Is H or C1-C12An alkyl group.
Compared with the inorganic metal salt catalyst such as lithium chloride used in the prior art, the benzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate serving as the catalyst in the invention can be easily and thoroughly removed from the reaction system (for example, can be removed by washing with an organic solvent), solves the problem that the thermodynamic property and mechanical property of the prepared polymer are adversely affected due to catalyst residue, can prepare the furan-based polyamide polymer through a simple reaction process under mild reaction conditions (at normal temperature and normal pressure), and is cheap and easy to obtain.
In the present invention, the molecular weight of the obtained furyl aromatic polyamide can be determined by methods well known to those skilled in the art. For example, it can be obtained using Gel Permeation Chromatography (GPC).
The high molecular weight furyl aromatic polyamide provided by the invention has excellent thermodynamic property and mechanical property, and can be applied to preparing fibers, membrane materials, nano particles/polymer composite materials and the like. For example, a solution obtained by dissolving the obtained polymer in a suitable solvent, wherein the content of the polymer may be, for example, 0.1 to 50% by weight, may be formed into fibers or filaments by means of the spinning techniques of the resins of the art. The resulting fibers or filaments may be treated using conventional techniques to neutralize, wash, dry and/or heat treat the fibers or filaments to provide stable and useful fibers or filaments.
The invention has the beneficial effects that: according to the invention, benzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is used as a catalyst to replace a common inorganic metal salt catalyst in the prior art, so that the problem that the thermodynamic property and the mechanical property of the prepared polymer are adversely affected due to catalyst residue can be solved, the furan-based polyamide polymer can be prepared by using the catalyst through a simple reaction process at normal temperature and normal pressure, and the prepared furan-based polyamide polymer can be applied to the fields of preparation of fibers, membrane materials, nano-particle/polymer composite materials and the like.
The specific implementation mode is as follows:
in order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.
Example 1
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylformamide dissolved with 1.5mol of propane diamine at 25 ℃, 2.5mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 8 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 2
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylformamide dissolved with 1mol of propylene diamine at 25 ℃, 2.5mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 3
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylformamide dissolved with 1mol of propane diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished to obtain the furyl polyamide.
Example 4
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 5
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 6
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N-methylpyrrolidone dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished to obtain the furyl polyamide.
Example 7
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into acetonitrile dissolved with 1mol of propane diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, a product is separated to obtain the furan-based polyamide.
Example 8
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of p-phenylenediamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 9
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of m-phenylenediamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 10
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 11
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of ethylenediamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, a product is separated, so that the furyl polyamide is obtained.
Example 12
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of 1, 4-butanediamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, a product is separated, so that the furyl polyamide is obtained.
Example 13
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of 2, 3-diaminotoluene at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, a product is separated, so that the furyl polyamide is obtained.
Example 14
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of 4, 4-diaminodiphenylmethane at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, the product is separated, so that the furyl polyamide is obtained.
Example 15
Under the condition of normal pressure, 1mol of furan-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and a product is separated after the reaction is finished, so that the furyl polyamide is obtained.
Example 16
Under the condition of normal pressure, 1mol of 3-methylfuran-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, the product is separated, so that the furyl polyamide is obtained.
Example 17
Under the condition of normal pressure, 1mol of 3, 4-dimethylfuran-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, a product is separated to obtain the furyl polyamide.
Example 18
Under the condition of normal pressure, 1mol of 3, 4-diethylfuran-2, 5-dicarboxylic acid is added into N, N-dimethylacetamide dissolved with 1mol of propylene diamine at 25 ℃, 4mol of benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate is added, the obtained mixture is stirred and reacts for 5 hours under the protection of inert gas, and after the reaction is finished, a product is separated to obtain the furyl polyamide.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (9)
1. A method for catalytically synthesizing furyl polyamide under normal pressure is characterized in that: under the condition of normal pressure, adding furan-2, 5-dicarboxylic acid into a propane diamine solution at the temperature of-10-40 ℃, adding benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate, stirring the obtained mixture under the protection of inert gas for reaction, and separating a product after the reaction is finished to obtain the furyl polyamide.
2. The process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to claim 1, wherein: the propane diamine solution is obtained by dissolving propane diamine in an organic solvent.
3. The process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to claim 2, wherein: the organic solvent is at least one of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone and acetonitrile.
4. The process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to claim 2, wherein: the mass ratio of the organic solvent to the propane diamine is (1:1) - (10: 1).
5. The process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to claim 1, wherein: the molar ratio of the furan-2, 5-dicarboxylic acid to the propane diamine is (1:1) - (1: 10).
6. The process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to claim 1, wherein: the molar ratio of the benzotriazole-N, N, N ', N' -tetramethylurea hexafluorophosphate to the furan-2, 5-dicarboxylic acid is (2:1) - (12: 1).
7. The process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to claim 1, wherein: the reaction time is 1-24 h.
8. Process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to any of claims 1 to 7, wherein: the propane diamine can be replaced by p-phenylenediamine, m-phenylenediamine, ethylenediamine, 1, 4-butanediamine, 2, 3-diaminotoluene or 4, 4-diaminodiphenylmethane.
9. Process for the catalytic synthesis of furanyl polyamides under atmospheric pressure according to any of claims 1 to 7, wherein: the furan-2, 5-dicarboxylic acid may be replaced with a furan-2, 5-dicarboxylic acid derivative.
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Citations (2)
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CN107857746A (en) * | 2017-11-10 | 2018-03-30 | 东华大学 | The crosslinked polyamide of a kind of furyl diacid monomer and soluble aromatic polyamides with repeating processing and its preparation method and application |
CN110256668A (en) * | 2019-06-04 | 2019-09-20 | 中国科学技术大学 | High molecular weight furyl aromatic polyamides and its preparation method and application |
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CN107857746A (en) * | 2017-11-10 | 2018-03-30 | 东华大学 | The crosslinked polyamide of a kind of furyl diacid monomer and soluble aromatic polyamides with repeating processing and its preparation method and application |
CN110256668A (en) * | 2019-06-04 | 2019-09-20 | 中国科学技术大学 | High molecular weight furyl aromatic polyamides and its preparation method and application |
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