CN109970973B - Nylon 1 and preparation method and application thereof - Google Patents
Nylon 1 and preparation method and application thereof Download PDFInfo
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- CN109970973B CN109970973B CN201711448265.8A CN201711448265A CN109970973B CN 109970973 B CN109970973 B CN 109970973B CN 201711448265 A CN201711448265 A CN 201711448265A CN 109970973 B CN109970973 B CN 109970973B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/18—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of substituted ureas
- C07C273/1872—Preparation of compounds comprising a -N-C(O)-N-C(O)-N- moiety
- C07C273/1881—Preparation of compounds comprising a -N-C(O)-N-C(O)-N- moiety from urea
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C275/00—Derivatives of urea, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C275/46—Derivatives of urea, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups containing any of the groups, X being a hetero atom, Y being any atom, e.g. acylureas
- C07C275/58—Y being a hetero atom
- C07C275/62—Y being a nitrogen atom, e.g. biuret
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G71/00—Macromolecular compounds obtained by reactions forming a ureide or urethane link, otherwise, than from isocyanate radicals in the main chain of the macromolecule
- C08G71/02—Polyureas
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/54—Improvements relating to the production of bulk chemicals using solvents, e.g. supercritical solvents or ionic liquids
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Abstract
The invention belongs to the field of functional polymer materials, and particularly relates to nylon 1, a preparation method thereof and application thereof in the direction of an electric functional material. The structural formula of the nylon 1 is
In the formula R1、R2Is a terminal capping group, and n is 10 to 500, more preferably 10 to 300. The nylon 1 has amide bonds, peptide bonds and urea bonds with the highest density, the maximum dipole concentration and the maximum dipole moment, the thermal decomposition temperature of the nylon 1 reaches 280-370 ℃, and the molecular structure is regular. The invention further provides a preparation method of the nylon 1, in particular to a method for preparing the nylon 1 polymer with expected polymerization degree by using supercritical carbon dioxide to perform condensation polymerization of urea, no toxic substance is used or generated in the whole reaction process, no pollution is caused to the environment, and CO is realized by adopting a green synthesis process2The comprehensive and effective utilization of the process is realized. The invention further provides the use of the aforementioned nylon 1 as a ferroelectric material.
Description
Technical Field
The invention belongs to the field of functional polymer materials, and particularly relates to nylon 1, a preparation method thereof and application thereof in the direction of an electric functional material.
Background
Nylon (polyamide) has been used as the earliest polymer material for industrialization for over 50 years, and is widely applied to the fields of machinery, traffic, electricity, chemical industry, textile and daily necessities due to small specific gravity, wear resistance, oil resistance and easy processing. In recent years, research on special electrical properties of odd nylon (such as nylon 11, nylon 7, nylon 5 and the like) shows that the odd nylon has excellent ferroelectric, thermoelectric, piezoelectric and dielectric properties and has wide application prospects as an electronic sensor (the odd nylon is a ferroelectric polymer with super-strong dielectric effect, and the introduction of the first Chinese functional material and the academic conference thereof (1992)).
At present, the preparation of odd nylon mainly uses non-renewable downstream petroleum products as raw materials, and mainly adopts diacid-diamine system condensation polymerization or lactam ring-opening polymerization. At present, part of products are industrialized, but the problems of low yield, consumption of non-renewable resources, influence on environment by raw materials and the like exist.
For piezoelectric materials, PVDF and VDF copolymers are still the only commercially viable piezoelectric polymers. Nylon has a series of excellent comprehensive properties, so that nylon becomes a piezoelectric polymer with the most application potential. Odd nylons including nylon 5, nylon 7, nylon 9 and nylon 11, which have been reported so far, have ferroelectricity and piezoelectricity, and the remanent polarization and coercive electric field of the odd nylons linearly increase with the increase of the dipole density. In theory, nylon 1 has the highest density of amide, peptide, urea, imide and hydrogen bonds, with a very large dipole moment, five times the dipole concentration of nylon 11. However, nylon 1 with very low molecular weight, such as biuret and triurea, can only be prepared at present, and is mainly used in the fields of fertilizer, feed, adhesive, special reagent and the like, and the piezoelectric functional nylon 1 with higher molecular weight is not reported at home and abroad.
Disclosure of Invention
The invention aims to provide a high-performance nylon 1 product which has higher molecular weight and ideal thermal stability and mechanical performance on the premise of maintaining and improving the inherent good piezoelectric performance of odd nylon materials.
The invention also aims to provide the preparation method of the high-performance nylon 1, which is environment-friendly, high in production efficiency and controllable in cost.
It is another object of the present invention to provide an electronic device, particularly a polymer capacitor, containing the nylon 1.
Specifically, the invention provides nylon 1, which has the following molecular formula:
in the formula, R1、R2Is a terminal group, and n is preferably 10 to 500, more preferably 10 to 300.
Further, R1And R2The same or different, and one or more than two of hydroxyl, amino, alkyl and the like.
The invention also provides a preparation method of the nylon 1, which comprises the following steps:
s1, adding urea and an auxiliary agent into the reaction kettle, removing air in the kettle, heating and introducing carbon dioxide to make the carbon dioxide in a supercritical state;
s2, heating to the reaction temperature under stirring, and carrying out polycondensation reaction in supercritical carbon dioxide;
s3, stopping stirring, and then: when preparing the nylon 1 with n less than 100, directly carrying out the next step; when preparing nylon 1 with n being more than or equal to 100, curing the product of the step S2, and then carrying out the next step;
and S4, naturally cooling the reaction kettle to room temperature, and discharging.
Compared with the traditional urea condensation reaction, the method for synthesizing the nylon 1 fully utilizes the by-product NH generated in the reaction3，NH3And excess carbon dioxide to form urea, thereby eliminating the need for separate removal of by-products. The invention adopts cheap carbon dioxide and urea as raw materials, and adopts a one-pot methodThe nylon 1 with different molecular weights is prepared, so that the application range of the product is widened on the premise of keeping good piezoelectric performance of odd nylon.
As for the specific process parameters of the supercritical carbon dioxide polycondensation, from the viewpoint of reducing energy consumption, the temperature is preferably raised to 160 ℃ in the step S2, the pressure of the autoclave is preferably controlled to 7.4-20MPa, and the reaction time is further preferably controlled to 4-12 h.
Further, the auxiliary agent can be carbonate, organic acid salt, alkali metal salt of alcohol, preferably carbonate or bicarbonate, specifically can be selected from one or more of potassium carbonate, sodium carbonate, zinc carbonate, sodium bicarbonate, potassium bicarbonate, ammonium carbonate and ammonium bicarbonate in different proportions, and the dosage of the auxiliary agent is 0.1-5% of the mass of the urea.
In step S3, the stirring is stopped and then the step S4 is directly carried out, and the sticky nylon 1 with n less than 100 can be obtained; in order to prepare the powdered nylon 1 with n ≥ 100, the process may be performed before proceeding to step S4, specifically, the temperature is continuously raised after stopping stirring, and the process is performed at 200-.
Further, the preparation method further comprises the following steps:
s5, washing the product of the step S4 with water, washing with alcohol and drying.
Preferably, the step S5 sequentially uses deionized water and ethanol as detergents, and the drying treatment is drying at 80-120 ℃ for 3-8h under normal pressure or vacuum, preferably drying at 110 ℃ for 4h under vacuum.
The invention also provides the use of the nylon 1, including but not limited to its application as a ferroelectric material.
The nylon 1 molecule provided by the invention has amide bonds, peptide bonds and urea bonds with the highest density, has the maximum dipole concentration and the maximum dipole moment, and is a potential high-performance multifunctional material. While not wishing to be bound by any theory, it is speculated that the nylon 1 provided by the present invention has a planar molecular structure with a high density of hydrogen bonds as shown in fig. 1, and the structure has high stability, which is the structural basis for the nylon 1 to have the aforementioned properties.
The invention has the following beneficial effects:
1. the thermal decomposition temperature of the nylon 1 synthesized by the invention reaches 280-370 ℃, and the molecular structure is regular (XRD presents a single peak). The addition of 5 percent of the additive has remarkable improvement on the ferroelectric property of the nylon 11, so that the maximum polarization strength (P) of the nylon 11 at 20Mv/mmax) From 0.25mC/m2Increased to 1.35mC/m2。
2. In the whole reaction process, no toxic raw material is used, and the by-product is water and other non-toxic substances, so that compared with the traditional phosgene method or cyanuric chloride method, the method can avoid using substances with higher toxicity and cannot corrode a reaction container.
3. Compared with the traditional urea polycondensate synthesis, the polymer of the invention can reach 500 degree of polymerization, which is much higher than products with the degree of polymerization less than 6 such as biuret, triurea and tetraurea disclosed in the prior art; the invention avoids the defects of high cost and use or generation of extremely toxic substances of cyanogen acids in the urea polycondensation process in the prior art, does not use or generate any toxic substance in the whole process, does not pollute the environment, and realizes CO2The comprehensive and effective utilization of the method and the device realize a green synthesis process.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.
Fig. 1 is a schematic molecular structure diagram of nylon 1 provided by the present invention.
FIG. 2 is an NMR spectrum of nylon 1 prepared in example 3.
FIG. 3 is an XRD spectrum of nylon 1 prepared in example 3.
FIG. 4 is a TG curve of nylon 1 prepared in example 3.
FIG. 5 shows the curves of the hysteresis loop of nylon 1 prepared in example 3 before and after it is applied to the modification of the ferroelectric properties of nylon 11.
Detailed Description
The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1: oligomer nylon 1, average degree of polymerization n is 10.
Putting 60g of urea and 0.3g of potassium carbonate into a high-pressure reaction kettle, vacuumizing to remove air in the kettle, heating to 32 ℃, and introducing carbon dioxide to ensure that the pressure in the kettle is 8-9MPa and the carbon dioxide is in a supercritical state. Stirring and heating to 135 ℃, continuously reacting for 4 hours, stopping stirring, closing heating, naturally cooling the reaction kettle to room temperature, and discharging. Then, the impurities such as urea, auxiliary agent and the like which do not participate in the reaction in the product are cleaned by water and ethanol, and the filtration is carried out. Finally dried under vacuum at 110 ℃ for 4 hours. 40.8g of powdered oligomer nylon 1 was obtained with a yield of 68%. The intrinsic viscosity measured by an Ubbelohde viscometer with dimethyl sulfoxide as a solvent was 0.1044 dL/g.
Example 2: low molecular weight nylon 1, average degree of polymerization n is 30.
Putting 60g of urea and 0.3g of potassium carbonate into a high-pressure reaction kettle, vacuumizing to remove air in the kettle, heating to 32 ℃, and introducing carbon dioxide to ensure that the pressure in the kettle is 9-9.5MPa and the carbon dioxide is in a supercritical state. Stirring and heating to 140 ℃, continuously reacting for 5 hours, stopping stirring, closing heating, naturally cooling the reaction kettle to room temperature, and discharging. Then, the impurities such as urea, auxiliary agent and the like which do not participate in the reaction in the product are cleaned by water and ethanol, and the filtration is carried out. Finally dried under vacuum at 110 ℃ for 4 hours. 37.8g of low-molecular-weight nylon 1 was obtained in the form of powder with a yield of 63%. The intrinsic viscosity measured by an Ubbelohde viscometer with dimethyl sulfoxide as a solvent was 0.1872 dL/g.
Example 3: the average degree of polymerization of the medium molecular weight nylon 1, n, is 100.
Putting 60g of urea, 0.3g of potassium carbonate and 0.1g of zinc carbonate into a high-pressure reaction kettle, vacuumizing to remove air in the kettle, heating to 32 ℃, and introducing carbon dioxide to ensure that the pressure in the kettle is 10-12MPa and the carbon dioxide is in a supercritical state. Stirring was started and the temperature was raised to 145 ℃ for 7 hours, and stirring was stopped. Continuously heating to 260 ℃ for curing for 2 hours, closing the heating, naturally cooling the reaction kettle to room temperature, and discharging. Then, impurities such as urea, catalyst and the like which do not participate in the reaction in the product are cleaned by water and ethanol, and are filtered. Finally dried under vacuum at 110 ℃ for 4 hours. 33.6g of powdery nylon 1 having a medium molecular weight was obtained in a yield of 56%. The intrinsic viscosity measured by an Ubbelohde viscometer with dimethyl sulfoxide as a solvent was 0.3587 dL/g. The NMR spectrum (deuterated DMSO is used as solvent), XRD diffraction spectrum and thermal weight loss curve of the product are respectively shown in figures 2, 3 and 4.
In FIG. 2, a in the graph (a) is the peak of the H proton linked to N in the repeating unit; in FIG. b, b is a peak of carbonyl carbon atoms in the repeating unit.
Example 4: high molecular weight nylon 1 had an average degree of polymerization n of 300.
Putting 60g of urea, 0.3g of potassium carbonate and 0.2g of zinc carbonate into a high-pressure reaction kettle, vacuumizing to remove air in the kettle, heating to 32 ℃, and introducing carbon dioxide to ensure that the pressure in the kettle is 13-15MPa and the carbon dioxide is in a supercritical state. Stirring was started and the temperature was raised to 155 ℃ for 10 hours, and stirring was stopped. Continuously heating to 300 ℃ for curing for 2 hours, closing the heating, naturally cooling the reaction kettle to room temperature, and discharging. Then, impurities such as urea, catalyst and the like which do not participate in the reaction in the product are cleaned by water and ethanol, and are filtered. Finally dried under vacuum at 110 ℃ for 4 hours. 30.6g of powdery high molecular weight nylon 1 was obtained in 51% yield. The intrinsic viscosity measured by an Ubbelohde viscometer with dimethyl sulfoxide as a solvent was 0.6529 dL/g.
Example 5
Nylon 1 prepared in example 3 and nylon 11 were mixed at a mass ratio of 5:95, and the hysteresis loop curve of the mixture is shown in FIG. 5.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (4)
1. The preparation method of nylon 1 is characterized by comprising the following steps:
s1, adding urea and an auxiliary agent into the reaction kettle, removing air in the kettle, heating and introducing carbon dioxide to make the carbon dioxide in a supercritical state;
s2, heating to the reaction temperature under stirring, and carrying out polycondensation reaction in supercritical carbon dioxide; the polycondensation reaction is carried out at 7.4-20MPa and 100-160 ℃;
s3, stopping stirring, and then: when preparing the nylon 1 with n less than 100, directly carrying out the next step; when preparing nylon 1 with n being more than or equal to 100, curing the product of the step S2, and then carrying out the next step;
s4, naturally cooling the reaction kettle to room temperature, and discharging;
the auxiliary agent is selected from one or the combination of two or more of potassium carbonate, sodium carbonate, zinc carbonate, sodium bicarbonate, potassium bicarbonate, ammonium carbonate or ammonium bicarbonate;
the molecular formula of the nylon 1 is as follows:
in the formula, R1、R2Is a capping group, n = 10-300;
R1and R2Is an amino group.
2. The preparation method of the nylon 1 of claim 1, wherein the amount of the auxiliary agent is 0.1-5% of the mass of the urea.
3. The method for preparing nylon 1 of claim 1, wherein in step S2, the polycondensation reaction time is 4 to 12 hours.
4. The method for producing nylon 1 according to claim 1, wherein in step S3, the temperature is raised continuously after the stirring is stopped, and the aging is performed at 200 to 360 ℃.
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Citations (5)
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| US3671542A (en) * | 1966-06-13 | 1972-06-20 | Du Pont | Optically anisotropic aromatic polyamide dopes |
| JPS5366897A (en) * | 1976-11-29 | 1978-06-14 | Mitsui Toatsu Chem Inc | Concentrating method for aqueous ammonia solution by reverse osmosis |
| CN1083806A (en) * | 1992-05-08 | 1994-03-16 | 乌里阿·卡萨勒有限公司 | Improved process for producing urea |
| CN102040400A (en) * | 2010-11-19 | 2011-05-04 | 中北大学 | Green synthesis process of slow release carbon base nitrogen fertilizer |
| CN107428896A (en) * | 2015-02-03 | 2017-12-01 | 伊利诺伊大学董事会 | For polymerizeing the ring-type dynamic polyureas of urea production |
-
2017
- 2017-12-27 CN CN201711448265.8A patent/CN109970973B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3671542A (en) * | 1966-06-13 | 1972-06-20 | Du Pont | Optically anisotropic aromatic polyamide dopes |
| JPS5366897A (en) * | 1976-11-29 | 1978-06-14 | Mitsui Toatsu Chem Inc | Concentrating method for aqueous ammonia solution by reverse osmosis |
| CN1083806A (en) * | 1992-05-08 | 1994-03-16 | 乌里阿·卡萨勒有限公司 | Improved process for producing urea |
| CN102040400A (en) * | 2010-11-19 | 2011-05-04 | 中北大学 | Green synthesis process of slow release carbon base nitrogen fertilizer |
| CN107428896A (en) * | 2015-02-03 | 2017-12-01 | 伊利诺伊大学董事会 | For polymerizeing the ring-type dynamic polyureas of urea production |
Non-Patent Citations (3)
| Title |
|---|
| 1222774-21-1;CHEBI;《STN REGISTRY》;20100313;CAS 1222774-21-1 * |
| CHEBI.1222774-21-1.《STN REGISTRY》.2010, * |
| The ferroelectric behavior of odd-numbered nylons;B.Z.Mei;《Ferroelectrics》;19931231(第144期);第54页表1、第1段和第58页第1段 * |
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