CN112661957A - Environment-friendly synthetic method of furyl polyamide - Google Patents
Environment-friendly synthetic method of furyl polyamide Download PDFInfo
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- CN112661957A CN112661957A CN202011530950.7A CN202011530950A CN112661957A CN 112661957 A CN112661957 A CN 112661957A CN 202011530950 A CN202011530950 A CN 202011530950A CN 112661957 A CN112661957 A CN 112661957A
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Abstract
The invention discloses a green synthesis method of furan-based polyamide, which relates to the technical field of chemical synthesis, compared with the prior art, the invention uses 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate as a catalyst, has the characteristics of simple feeding mode, mild reaction, easily obtained raw materials and the like, and is suitable for industrial implementation; the prepared furyl aromatic polyamide has excellent thermodynamic property and mechanical property, can be applied to preparing fibers, membrane materials and nano particle/polymer composite materials, and has wide application range.
Description
The technical field is as follows:
the invention relates to the technical field of polyamide synthesis, in particular to a green synthesis method of furyl polyamide.
Background art:
the polyamide has the outstanding advantages of excellent mechanical property, good self-lubricating and friction-resistant properties, high heat-resistant temperature, high electrical insulation and the like, is widely applied to the fields of machinery, automobiles, electrical appliances, textile equipment, chemical equipment, aviation, metallurgy and the like, is a large amount of engineering plastics, and has important significance on national economy, social development and national defense safety. With the development of society, the demand of polyamide compounds is rapidly increasing.
The monomer 2, 5-furandicarboxylic acid of furan-based polyamides is made from biomass derived from renewable resources, as compared to petroleum-based polyamides, and CO is compared to petroleum-based feedstocks2The gas emission is obviously reduced, so the environmental friendliness is greatly improved, andone of the 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.
CN105801843A discloses a semi-biomass furyl soluble aromatic polyamide and a preparation method and application thereof. Although a furandicarboxylic acid monomer which can be derived from a biomaterial is used, wherein essential monomers for obtaining the aromatic polyamide are furandicarboxylic acid or a derivative thereof and p-phenylenediamine, and an inorganic metal salt is used as a catalyst in the synthesis thereof, it is difficult to completely remove the inorganic metal salt such as LiCl in a reaction system, and the residual inorganic salt reduces mechanical properties and mechanical system properties of the polyamide product; meanwhile, the synthesis method needs to be completed in multiple steps at a high temperature of 90-130 ℃ (namely the preparation process is complex), and the obtained aromatic polyamide has a low number average molecular weight (lower than 200000).
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 green synthesis method of furan-based polyamide, 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is used as a catalyst, furan diacid monomer and diamine monomer are used for preparing furan-based polyamide, compared with petroleum-based polyamide, the environment friendliness of furan-based polyamide is greatly improved, and the method is suitable for industrial production and has good processability.
The technical problem to be solved by the invention is realized by adopting the following technical scheme:
a green synthesis method of furan-based polyamide comprises the steps of dissolving diamine monomer in an organic solvent to form a diamine solution under the protection of inert gas, adding furan diacid monomer into the diamine solution, adding a catalyst, reacting under stirring, and separating a product after the reaction is finished to obtain the furan-based polyamide.
The organic solvent is selected from one or more of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone and acetonitrile.
The mass ratio of the organic solvent to the diamine monomer is (1:1) - (10:1), preferably 5: 1.
The molar ratio of the furan diacid monomer to the diamine monomer is (1:1) - (1:10), preferably 1: 1.
The diamine monomer is any one of propane diamine, p-phenylene diamine, m-phenylene diamine, ethylene diamine, 1, 4-butanediamine, 2, 3-diaminotoluene and 4, 4-diaminodiphenylmethane.
The structural formula of the furan diacid monomer is as follows:
wherein R is1、R2Is H or C1-C12An alkyl group.
The addition temperature of the diacid monomer is-10 ℃ to 40 ℃.
The catalyst is 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate.
The molar ratio of the catalyst to the diacid monomer is (2:1) - (12: 1).
The reaction time is 1-24h, preferably 5 h.
The separation is performed by chromatography or chromatography.
Taking furan-2, 5-dicarboxylic acid and propane diamine as examples, the reaction equation is:
compared with the inorganic metal salt catalyst such as lithium chloride used in the prior art, the 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate used 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 and mechanical properties of the prepared polymer are adversely affected due to catalyst residues, and can prepare the furan-based polyamide polymer through a simple reaction process under mild reaction conditions (at normal temperature and normal pressure), and the catalyst 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: compared with the prior art, the method uses 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate as a catalyst, has the characteristics of simple feeding mode, mild reaction, easily obtained raw materials and the like, and is suitable for industrial implementation; the prepared furyl aromatic polyamide has excellent thermodynamic property and mechanical property, can be applied to preparing fibers, membrane materials and nano particle/polymer composite materials, and has wide application range.
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 protection of inert gas, 1mol of propylene diamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 2
Under the protection of inert gas, 1mol of propylene diamine is dissolved in acetonitrile (the amount of the acetonitrile is 8 times of the mass of the diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the mixture is reacted for 4 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 3
Under the protection of inert gas, 1.5mol of propylene diamine is dissolved in N-methyl pyrrolidone (the amount of the N-methyl pyrrolidone is 5 times of the mass of the diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at 30 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 4
Under the protection of inert gas, 2mol of propylene diamine is dissolved in N, N-dimethylacetamide (the amount of N, N-dimethylacetamide is 5 times of the mass of diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 6 hours under stirring, and after the reaction is finished, a product is separated by chromatography to obtain the furyl polyamide.
Example 5
Under the protection of inert gas, 1mol of p-phenylenediamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 6
Under the protection of inert gas, 1mol of 2, 3-diaminotoluene is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 7
Under the protection of inert gas, 1mol of 4, 4-diaminodiphenylmethane is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 8
Under the protection of inert gas, 1mol of 1, 4-butanediamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of furan-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 9
Under the protection of inert gas, 1mol of propylene diamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3-methylfuran-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 10
Under the protection of inert gas, 1mol of propane diamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3, 4-dimethylfuran-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 11
Under the protection of inert gas, 1mol of propylene diamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3-ethylfuran-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 6 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 12
Under the protection of inert gas, 1mol of propylene diamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3-propylfuran-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 6 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 13
Under the protection of inert gas, 1mol of p-phenylenediamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3-methylfuran-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 14
Under the protection of inert gas, 1mol of ethylenediamine is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3-methylfuran-2, 5-dicarboxylic acid is added into the diamine solution at the temperature of 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 15
Under the protection of inert gas, 1mol of 2, 3-diaminotoluene is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3-methylfuran-2, 5-dicarboxylic acid is added into the diamine solution at 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography to obtain the furyl polyamide.
Example 16
Under the protection of inert gas, 1mol of 4, 4-diaminodiphenylmethane is dissolved in N, N-dimethylformamide (the amount of the N, N-dimethylformamide is 5 times of the mass of the diamine) to form a diamine solution, 1mol of 3-methylfuran-2, 5-dicarboxylic acid is added into the diamine solution at 20 ℃, 3mol of 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate is added at the same time, the reaction is carried out for 5 hours under stirring, and after the reaction is finished, a product is separated by utilizing chromatography 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 (10)
1. A green synthesis method of furyl polyamide is characterized in that: under the protection of inert gas, dissolving a diamine monomer in an organic solvent to form a diamine solution, adding a furan diacid monomer into the diamine solution, adding a catalyst, reacting under stirring, and separating a product after the reaction is finished to obtain the furan-based polyamide.
2. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the organic solvent is selected from one or more of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone and acetonitrile.
3. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the mass ratio of the organic solvent to the diamine monomer is (1:1) - (10: 1); the molar ratio of the furan diacid monomer to the diamine monomer is (1:1) - (1: 10).
4. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the diamine monomer is any one of propane diamine, p-phenylene diamine, m-phenylene diamine, ethylene diamine, 1, 4-butanediamine, 2, 3-diaminotoluene and 4, 4-diaminodiphenylmethane.
5. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the structural formula of the furan diacid monomer is as follows:
wherein R is1、R2Is H or C1-C12An alkyl group.
6. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the addition temperature of the diacid monomer is-10 ℃ to 40 ℃.
7. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the catalyst is 6-chlorobenzotriazole-1, 1,3, 3-tetramethylurea hexafluorophosphate.
8. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the molar ratio of the catalyst to the diacid monomer is (2:1) - (12: 1).
9. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the reaction time is 1-24 h.
10. The green synthesis process of furan-based polyamide according to claim 1, characterized in that: the separation is performed by chromatography or chromatography.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103974765A (en) * | 2011-09-15 | 2014-08-06 | 因思特艾克申有限公司 | Sorbent comprising on its surface an aliphatic unit for the purification of organic molecules |
| CN105801843A (en) * | 2016-04-19 | 2016-07-27 | 东华大学 | Semi-biomass furyl soluble aromatic polyamide and preparation method and application thereof |
| 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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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103974765A (en) * | 2011-09-15 | 2014-08-06 | 因思特艾克申有限公司 | Sorbent comprising on its surface an aliphatic unit for the purification of organic molecules |
| CN105801843A (en) * | 2016-04-19 | 2016-07-27 | 东华大学 | Semi-biomass furyl soluble aromatic polyamide and preparation method and application thereof |
| 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 |
Non-Patent Citations (1)
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| 王德心: "《活性多肽与药物开发》", 30 June 2008, 中国医药科技出版社 * |
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