Supramolecular catalyst based on beta-diimine as well as preparation method and application of supramolecular catalyst

Abstract

The invention relates to a supramolecular catalyst based on beta-diimine as well as a preparation method and application of the supramolecular catalyst. The invention relates to application of a beta-diimine-based supramolecular catalyst in preparation of polyester. The relative position of metal in the supramolecular catalyst based on beta-diimine is controllable, adaptive monomer structures are diversified, the variety of prepared polyesters is rich, the application range of the polyesters is widened, and meanwhile, the supramolecular catalyst based on beta-diimine has the prospect of realizing industrial production.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to a supramolecular catalyst based on beta-diimine and a preparation method and application thereof. Background Art

[0002] Among the numerous polyester synthesis routes, compared with lactone ring opening and polycondensation of polyols and polyacids, the preparation of polyester by copolymerization of alkylene oxides and cyclic anhydrides has the advantages of high conversion rate, high atom economy, and easy control of the molecular weight and molecular weight distribution of polyester; the prepared polyester has good renewability, biocompatibility and degradability.

[0003] Despite the advantages of this route, the current technical defects also limit its wide-scale application. The main reasons are the limited understanding of the structure-property relationship of polyester and the single or unsuitable synthesis methods for industrial production, which is mainly reflected in the lack of high-performance catalysts. Metal catalysts based on β-diimine have high reactivity and selectivity and are one of the most widely used catalytic systems. However, the catalytic efficiency of this catalyst still cannot meet the large-scale production of this polymer.

[0004] The present invention fully studies the catalytic mechanism of the metal catalyst based on β-diimine, strives to improve the disadvantage of insufficient catalytic efficiency of the catalytic system, and designs and synthesizes a supramolecular catalyst based on β-diimine. Summary of the invention

[0005] In view of the deficiencies of the prior art, the present invention provides a supramolecular catalyst based on β-diimine and a preparation method and application thereof.

[0006] To this end, the first aspect of the present invention provides a supramolecular catalyst based on β-diimine, wherein the supramolecular catalyst has the structure of the following formula (1):

[0007]

[0008] Wherein, m≥1 and is an integer; n≥1 and is an integer; M and M1 are the same or different, and are independently selected from metal elements; X and Y are the same or different, and are independently selected from Lewis acid ions.

[0009] In some embodiments of the present invention, the M is selected from any one of Co, Al, Cr, and Zn.

[0010] In some embodiments of the present invention, the M1 is selected from any one of Li, Na, and K.

[0011] In some embodiments of the present invention, X is selected from Cl -1 、NO3 -1 、ClO4-1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4 -1 、N3 -1 Any one of .

[0012] In some embodiments of the present invention, Y is selected from Cl -1 、NO3 -1 、ClO4 -1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4 -1 、N3 -1 Any one of .

[0013] In some embodiments of the present invention, m=1, 2, 3.

[0014] In some embodiments of the present invention, n=1, 2, 3.

[0015] The supramolecular catalyst connects two metal centers through a cyclic ligand, improving the problem of low catalytic activity of single metal. The cyclic ligand contains multiple coordination active centers, among which the number of oxygen atoms is adjustable, and the distance between oxygen atoms and nitrogen atoms is adjustable. At the same time, the cyclic ligand is flexible, and the bimetallic can be adjusted to a suitable distance according to different monomers. Through the synergistic catalysis of the bimetallic, the epoxyalkane and the cyclic anhydride are copolymerized. In addition, the bimetallic catalyst structure is more stable, and the ligand and metal are more tightly bound, so that the supramolecular catalyst can be stably stored in the air without the need for anhydrous and oxygen-free protection.

[0016] The second aspect of the present invention provides a method for preparing a supramolecular catalyst based on β-diimine, comprising reacting malondialdehyde and polyol diamine at 0.1-3Mpa under the protection of an inert gas to obtain a cyclic ligand, mixing the cyclic ligand with MY, dissolving the cyclic ligand with an organic solvent 1 and reacting the mixture, and then adding M1X to react to obtain a supramolecular catalyst based on β-diimine.

[0017] In some embodiments of the present invention, after the addition of M1X for reaction, the organic solvent 1 is removed under reduced pressure, and then the organic solvent 2 is added for washing and filtration, and the filter cake is collected and vacuum dried.

[0018] In some embodiments of the present invention, the molar ratio of malondialdehyde to polyol diamine is 0.8-2.0:1.

[0019] In some embodiments of the present invention, after the reaction of the malondialdehyde and the polyol diamine, the excess malondialdehyde is removed under reduced pressure.

[0020] In some embodiments of the present invention, the molar ratio of the cyclic ligand to MY is 0.8-2.0:1.

[0021] In some embodiments of the present invention, the molar ratio of the cyclic ligand to M1X is 0.8-2.0:1.

[0022] In some embodiments of the present invention, the organic solvent 1 includes any one of dichloromethane, dichloroethane, 1,4-dioxane, toluene, and tetrahydrofuran.

[0023] In some embodiments of the present invention, the organic solvent 2 includes any one of cyclohexane, n-hexane, methanol, ethanol, and isopropanol.

[0024] In some embodiments of the present invention, the reaction temperature of the malondialdehyde and the polyol diamine is 100-150° C., and the reaction time is 16-24 hours.

[0025] In some embodiments of the present invention, the reaction temperature of the cyclic ligand and MY is 25-40° C., and the reaction time is 20-24 h.

[0026] In some embodiments of the present invention, the reaction temperature after adding M1X is 75-100° C., and the reaction time is 20-24 h.

[0027] In some embodiments of the present invention, the washing and filtration are repeated 2-5 times, preferably 3 times.

[0028] In some embodiments of the present invention, the M is selected from any one of Co, Al, Cr, and Zn.

[0029] In some embodiments of the present invention, the M1 is selected from any one of Li, Na, and K;

[0030] In some embodiments of the present invention, X is selected from Cl -1 、NO3 -1 、ClO4 -1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4 -1 、N3 -1 Any of the following:

[0031] In some embodiments of the present invention, Y is selected from Cl -1 、NO3 -1 、ClO4 -1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4-1 、N3 -1 Any one of .

[0032] In some embodiments of the present invention, the polyol diamine has a structure of the following formula (2):

[0033]

[0034] Wherein, m≥1 and is an integer; n≥1 and is an integer.

[0035] In some embodiments of the present invention, m=1, 2, 3.

[0036] In some embodiments of the present invention, n=1, 2, 3.

[0037] In some embodiments of the present invention, the cyclic ligand has a structure of the following formula (3):

[0038]

[0039] Wherein, m≥1 and is an integer; n≥1 and is an integer.

[0040] In some embodiments of the present invention, m=1, 2, 3.

[0041] In some embodiments of the present invention, n=1, 2, 3.

[0042] In some embodiments of the present invention, the synthesis reaction equation of the supramolecular catalyst based on β-diimine is:

[0043]

[0044] The third aspect of the present invention provides a supramolecular catalyst prepared by the method described in the second aspect of the present invention.

[0045] The fourth aspect of the present invention provides a use of the supramolecular catalyst described in the first aspect of the present invention or the supramolecular catalyst described in the third aspect of the present invention in the preparation of polyester.

[0046] The fifth aspect of the present invention provides a method for preparing polyester, comprising mixing a supramolecular catalyst based on β-diimine, alkylene oxide and cyclic anhydride, selectively adding an organic solvent 3 to react at 0.1-3Mpa to obtain a crude product; washing and precipitating the crude product to obtain polyester.

[0047] In some embodiments of the present invention, the crude product is dissolved in dichloromethane, methanol is added, and the mixture is stirred vigorously to precipitate the polymer.

[0048] In some embodiments of the present invention, the crude product washing precipitate is repeated 3-5 times.

[0049] In some embodiments of the present invention, the molar ratio of the β-diimine-based supramolecular catalyst to the alkylene oxide is 1:300-10000.

[0050] In some embodiments of the present invention, the molar ratio of the alkylene oxide to the cyclic anhydride is 0.2-1.2:1.

[0051] In some embodiments of the present invention, the organic solvent 3 includes any one of 1,4-dioxane, toluene, xylene, and ethylene dichloride.

[0052] In some embodiments of the present invention, the reaction comprises the following conditions: the reaction temperature is 25-130° C., preferably 80-120° C.; and / or the reaction time is 2.0-12.0 h.

[0053] In some embodiments of the present invention, the cyclic anhydride is selected from any one of the cyclic anhydrides of the following structures:

[0054]

[0055] In some embodiments of the present invention, the alkylene oxide is selected from any one of the alkylene oxides of the following structures:

[0056]

[0057] In some embodiments of the present invention, the number average molecular weight of the polyester is ≥3.0 kg / mol.

[0058] In some embodiments of the present invention, the number average molecular weight of the polyester is 3.0-100.0 kg / mol.

[0059] In some embodiments of the present invention, the molecular weight distribution of the polyester is ≤1.3.

[0060] In some embodiments of the present invention, the molecular weight distribution of the polyester is 1.1-1.3.

[0061] Beneficial effects:

[0062] 1. The β-diimine-based supramolecular catalyst provided by the present invention uses a flexible cyclic ligand containing multiple coordination active centers, the number of oxygen atoms is adjustable, and the distance between oxygen atoms and nitrogen atoms is adjustable. Therefore, the relative position of the bimetal is controllable, the adaptable monomer structure is diverse, and a rich variety of polyesters can be prepared.

[0063] 2. The β-diimine-based supramolecular catalyst provided by the present invention is a heteronuclear multimetallic catalyst, which can achieve bimetallic synergistic catalysis and has higher activity than traditional monometallic catalysts, greatly reducing the proportion of catalyst usage.

[0064] 3. The β-diimine-based supramolecular catalyst provided by the present invention has a stable structure and a tight binding between the ligand and the metal, so that the supramolecular catalyst can be stably stored in the air without the need for anhydrous and oxygen-free protection.

[0065] 4. The polyester prepared using the supramolecular catalyst based on β-diimine provided by the present invention has a number average molecular weight of up to 99.7 kg / mol, a molecular weight distribution of 1.1-1.3, mild reaction conditions, and has industrial prospects. DETAILED DESCRIPTION

[0066] In order to make the present invention easier to understand, the present invention will be described in detail below with reference to embodiments. These embodiments are only for illustration and are not intended to limit the application scope of the present invention.

[0067] The reagents and materials used in the present invention are shown in Table 1:

[0068] Table 1 Reagents and materials

[0069] Raw material name Purity / Specification source Malondialdehyde Analytical grade Commercially available Polyol diamine Analytical grade Commercially available <![CDATA[Zn(NO3)2]]> Analytical grade Commercially available <![CDATA[Co(OAc)2]]> Analytical grade Commercially available

[0070] The structures of the alkylene oxide, cyclic anhydride and β-diimine-based supramolecular catalyst used in the examples are shown below:

[0071] Cyclic anhydrides:

[0072]

[0073] Alkylene oxide:

[0074]

[0075]

[0076] Example 1

[0077] The present embodiment provides a method for preparing a supramolecular catalyst based on β-diimine, comprising: adding 7.2 g of malondialdehyde (100.0 mmol) and 18.9 g of polyol diamine (90.9 mmol; n=1, m=1) into an autoclave under the protection of an inert gas, setting the pressure to 0.1 MPa, continuing to stir and react at 100° C. for 16 h, cooling to room temperature, and removing excess malondialdehyde under reduced pressure to obtain a cyclic ligand (n=1, m=1); under the protection of an inert gas, 2.4 g of cyclic ligand (10.0 mmol) and 1.8 g of Co(OAc)2 (10.0 mmol) were mixed, dissolved in dichloromethane and stirred at 25 °C for 24 h, and then 0.5 g of NaCl (8.0 mmol) was added. The reaction was stopped after stirring at 75 °C for 24 h, and the dichloromethane was removed under reduced pressure. Cyclohexane was added for washing and filtration. The filter cake was collected and repeated three times. The catalyst was dried in vacuo to obtain the supramolecular catalyst 1c based on β-diimine.

[0078] Example 2

[0079] The present embodiment provides a preparation method of a supramolecular catalyst based on β-diimine, comprising: adding 7.2 g of malondialdehyde and 25.5 g of polyol diamine (90.9 mmol; n=2, m=2) into an autoclave under inert gas protection, setting the pressure to 1 MPa, continuing to react at 120° C. with stirring for 19 h, cooling to room temperature, and removing excess malondialdehyde under reduced pressure to obtain a cyclic ligand (n=2, m=2); mixing 3.2 g of the cyclic ligand (10.0 mmol) and 2 g of CrCl3 (12.5 mmol) under inert gas protection, dissolving them with dichloroethane, stirring at 30° C. for 20 h, adding 0.4 g of LiCl (10.0 mmol), stirring at 95° C. for 22 h, stopping the reaction, removing dichloroethane under reduced pressure, adding n-hexane for washing, filtering, collecting the filter cake, repeating the process three times, and vacuum drying to obtain a supramolecular catalyst 2c based on β-diimine.

[0080] Example 3

[0081] The present embodiment provides a method for preparing a supramolecular catalyst based on β-diimine, comprising: adding 7.2 g of malondialdehyde and 32.0 g of polyol diamine (90.9 mmol; n=3, m=3) into an autoclave under inert gas protection, setting the pressure to 2 MPa, continuing to stir the reaction at 150° C. for 24 h, cooling to room temperature, and removing excess malondialdehyde under reduced pressure to obtain a cyclic ligand (n=3, m=3); mixing 3.9 g of the cyclic ligand (10.0 mmol) and 0.7 g of AlCl3 (5.0 mmol) under inert gas protection, dissolving the mixture with toluene, and stirring the mixture at 40° C. for 24 h, adding 0.7 g of CF3COOK (5.0 mmol), stirring the mixture at 100° C. for 22 h, stopping the reaction, removing toluene under reduced pressure, adding isopropanol for washing, filtering, collecting the filter cake, repeating the process three times, and vacuum drying to obtain a supramolecular catalyst 3c based on β-diimine.

[0082] Example 4

[0083] The present embodiment provides a method for preparing a supramolecular catalyst based on β-diimine, comprising: adding 7.2 g of malondialdehyde and 32.0 g of polyol diamine (n=3, m=3) into an autoclave under the protection of an inert gas, setting the pressure to 3 MPa, continuing to react at 150° C. with stirring for 24 h, cooling to room temperature, and removing excess malondialdehyde under reduced pressure to obtain a cyclic ligand (n=3, m=3); mixing 3.9 g of the cyclic ligand and 1.9 g of Zn(NO3)2 (10.0 mmol) under the protection of an inert gas, dissolving 1,4-dioxane in the mixture, stirring at 40° C. for 24 h, adding 0.7 g of KCl (10.0 mmol), stirring at 100° C. for 24 h, stopping the reaction, removing 1,4-dioxane under reduced pressure, adding ethanol for washing, filtering, collecting the filter cake, repeating three times, and vacuum drying to obtain a supramolecular catalyst 4c based on β-diimine.

[0084] Example 5

[0085] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas into the reactor for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 1c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 1c to the alkylene oxide 1b is 1:300, and the molar ratio of the alkylene oxide 1b to the cyclic anhydride 1a is 0.2:1, adding toluene, reacting at 0.1 MPa and 25° C. for 2 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using the reaction mixture for the reaction; 1 H NMR and GPC tests; the remaining crude polymer was dissolved in a small amount of dichloromethane, and a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly and vacuum dried to obtain polyester 1.

[0086] 1 H NMR test showed that the polyester alternation degree was 99.1%, and GPC test showed that the number average molecular weight was 3.9 kg / mol and the molecular weight distribution was 1.1.

[0087] Example 6

[0088] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas into the reactor for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 1c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 1c to the alkylene oxide 2b is 1:1000, and the molar ratio of the alkylene oxide 2b to the cyclic anhydride 2a is 0.5:1, adding 1,4-dioxane, reacting at 1 MPa and 50° C. for 3 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using the reaction mixture for the reaction; 1 H NMR and GPC tests; the remaining crude polymer was dissolved in a small amount of dichloromethane, and a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly and vacuum dried to obtain polyester 2.

[0089] 1 H NMR test showed that the polyester alternation degree was 99.2%, and GPC test showed that the number average molecular weight was 22.2 kg / mol and the molecular weight distribution was 1.1.

[0090] Example 7

[0091] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas into the reactor for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 2c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 2c to the alkylene oxide 3b is 1:2000, and the molar ratio of the alkylene oxide 3b to the cyclic anhydride 3a is 1:1, adding xylene, reacting at 2 MPa and 75° C. for 3.5 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using the reaction mixture for the reaction; 1 H NMR and GPC tests; the remaining crude polymer was dissolved in a small amount of dichloromethane, and a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly and vacuum dried to obtain polyester 3.

[0092] 1 H NMR test showed that the polyester alternation degree was 99.8%, and GPC test showed that the number average molecular weight was 28.9 kg / mol and the molecular weight distribution was 1.1.

[0093] Example 8

[0094] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas into the reactor for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 2c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 2c to the alkylene oxide 4b is 1:5000, and the molar ratio of the alkylene oxide 4b to the cyclic anhydride 4a is 1.2:1, adding ethylene dichloride, reacting at 3 MPa and 75° C. for 10 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using the reaction mixture for the reaction; 1 H NMR and GPC tests; the remaining crude polymer was dissolved in a small amount of dichloromethane, and a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly and vacuum dried to obtain polyester 4.

[0095] 1 H NMR test showed that the polyester alternation degree was 99.3%. GPC test showed that the number average molecular weight was 56.7 kg / mol and the molecular weight distribution was 1.1.

[0096] Example 9

[0097] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas into the reactor for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 3c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 3c to the alkylene oxide 5b is 1:5000, and the molar ratio of the alkylene oxide 5b to the cyclic anhydride 5a is 0.8:1, adding toluene, reacting at 3 MPa and 100° C. for 8.5 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using the reaction mixture for the reaction; 1 H NMR and GPC tests; the remaining crude polymer was dissolved in a small amount of dichloromethane, and a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly and vacuum dried to obtain polyester 5.

[0098] 1 H NMR test showed that the polyester alternation degree was 99.2%, and GPC test showed that the number average molecular weight was 99.7 kg / mol and the molecular weight distribution was 1.2.

[0099] Example 10

[0100] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas in preparation for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 3c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 3c to the alkylene oxide 6b is 1:10000, and the molar ratio of the alkylene oxide 6b to the cyclic anhydride 6a is 1:1, adding toluene, reacting at 0.7 MPa and 130° C. for 12 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using it for 1 H NMR and GPC tests; the remaining crude polymer was dissolved in a small amount of dichloromethane, and a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly and vacuum dried to obtain polyester 6.

[0101] 1 H NMR test showed that the polyester alternation degree was 99.0%, and GPC test showed that the number average molecular weight was 63.1 kg / mol and the molecular weight distribution was 1.3.

[0102] Embodiment 11

[0103] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas into the reactor for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 4c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 4c to the alkylene oxide 7b is 1:10000, and the molar ratio of the alkylene oxide 7b to the cyclic anhydride 7a is 0.9:1, adding 1,4-dioxane, reacting at 1.5 MPa and 120° C. for 6 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using the reaction mixture for the reaction; 1 H NMR and GPC test. The remaining reaction polymer crude product was dissolved in a small amount of dichloromethane, and then a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly, and the polyester 7 was obtained by vacuum drying.

[0104] 1 H NMR test showed that the polyester alternation degree was 99.4%, and GPC test showed that the number average molecular weight was 44.8 kg / mol and the molecular weight distribution was 1.3.

[0105] Example 12

[0106] The present embodiment provides a method for preparing polyester, comprising: drying a 100 mL high-pressure reactor equipped with a magnet at 120° C. for more than 12 hours, evacuating the reactor until it cools to room temperature, and flushing nitrogen gas in preparation for use; under nitrogen protection, weighing a certain amount of supramolecular catalyst 4c based on β-diimine at room temperature, wherein the molar ratio of the supramolecular catalyst 4c to alkylene oxide 8b is 1:10000, and the molar ratio of alkylene oxide 8b to cyclic anhydride 8a is 1:1, adding toluene, reacting at 0.5 MPa and 100° C. for 9 hours, stopping stirring, taking out a very small amount of the reaction polymer, and using it for 1 H NMR and GPC tests; the remaining crude polymer was dissolved in a small amount of dichloromethane, and a large amount of methanol was added and stirred vigorously to precipitate the polymer. This precipitation process was repeated repeatedly and vacuum dried to obtain polyester 8.

[0107] 1 H NMR test showed that the polyester alternation degree was 99.5%, and GPC test showed that the number average molecular weight was 42.4 kg / mol and the molecular weight distribution was 1.2.

[0108] Comparative Example 1

[0109] This comparative example provides a method for preparing a polyester which is the same as the method in Example 5, except that Co(OAc)2 and NaCl are used as catalysts.

[0110] The results showed that no polymer was precipitated, indicating that the polymerization reaction did not proceed.

[0111] From the test results of Examples 5-12, it can be seen that the polyesters 1-8 prepared using the supramolecular catalyst provided by the present application have a polyester alternation degree greater than 99.0%, which proves that the supramolecular catalyst provided by the present application has good selectivity, less prepared polyether by-products, and good material degradability; GPC test shows that the number average molecular weight can be as high as 99.7 kg / mol, which proves that the prepared polyether material has good mechanical properties; the molecular weight distribution is narrow, which proves that the active center of the supramolecular catalyst provided by the present application is uniform and the catalytic activity is high.

[0112] It can be seen from the results of comparative document 1 that when a traditional catalyst is used, if the same feed amount and reaction conditions as those of the supramolecular catalyst of the present application are still used, polymerization reaction cannot occur. This proves that the feed amount of the supramolecular catalyst of the present application is lower than that of the traditional catalyst, the reaction conditions are mild, and the catalytic efficiency is high.

[0113] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein, on the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A supramolecular catalyst based on β-diimine, characterized in that: The supramolecular catalyst has the structure of the following formula (1): Wherein, m≥1 and is an integer; n≥1 and is an integer; M and M1 are the same or different, and are independently selected from metal elements; X and Y are the same or different, and are independently selected from Lewis acid ions.

2. The supramolecular catalyst according to claim 1, characterized in that The M is selected from any one of Co, Al, Cr, and Zn; and / or the M1 is selected from any one of Li, Na, and K.

3. The supramolecular catalyst according to claim 1 or 2, characterized in that The X is selected from Cl -1 、NO3 -1 、ClO4 -1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4 -1 、N3 -1 Any one of; and / or, Y is selected from Cl -1 、NO3 -1 、ClO4 -1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4 -1 、N3 -1 Any one of .

4. A method for preparing a supramolecular catalyst based on β-diimine, characterized in that: The method comprises reacting malondialdehyde and polyol diamine at 0.1-3 Mpa under the protection of an inert gas to obtain a cyclic ligand, mixing the cyclic ligand with MY, dissolving the cyclic ligand with an organic solvent 1 and reacting the mixture, and then adding M1X to react to obtain a supramolecular catalyst based on β-diimine; Preferably, the molar ratio of the malondialdehyde to the polyol diamine is 0.8-2.0:1; and / or, the molar ratio of the cyclic ligand to MY is 0.8-2.0:1; and / or, the molar ratio of the cyclic ligand to M1X is 0.8-2.0:1; Preferably, the organic solvent 1 includes any one of dichloromethane, dichloroethane, 1,4-dioxane, toluene, and tetrahydrofuran; Preferably, the reaction temperature of the malondialdehyde and polyol diamine is 100-150°C, and the reaction time is 16-24h; and / or, the reaction temperature of the cyclic ligand and MY is 25-40°C, and the reaction time is 20-24h; and / or, the reaction temperature after adding M1X is 75-100°C, and the reaction time is 20-24h.

5. The method according to claim 4, characterized in that The M is selected from any one of Co, Al, Cr, and Zn; and / or, the M1 is selected from any one of Li, Na, and K; and / or, the X is selected from Cl -1 、NO3 -1 、ClO4 -1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4 -1 、N3 -1 Any one of; and / or, Y is selected from Cl -1 、NO3 -1 、ClO4 -1 ,BPh4 -1 CF3COO -1 、CH3COO -1 、BF4 -1 、N3 -1 Any one of .

6. Use of the supramolecular catalyst according to any one of claims 1 to 3 or the supramolecular catalyst prepared by the method according to claim 4 or 5 in the preparation of polyester.

7. A method for preparing polyester, characterized in that: The method comprises mixing a supramolecular catalyst based on β-diimine, an alkylene oxide and a cyclic acid anhydride, selectively adding an organic solvent 3 to react at 0.1-3 Mpa to obtain a crude product; washing and precipitating the crude product to obtain a polyester; Preferably, the molar ratio of the β-diimine-based supramolecular catalyst to the alkylene oxide is 1:300-10000; and / or the molar ratio of the alkylene oxide to the cyclic anhydride is 0.2-1.2:1; Preferably, the organic solvent 3 includes any one of 1,4-dioxane, toluene, xylene, and ethylene dichloride; Preferably, the reaction comprises the following conditions: the reaction temperature is 25-130° C., preferably 80-120° C.; and / or the reaction time is 2-12 h.

8. The method according to claim 7, characterized in that The cyclic anhydride is selected from any one of the cyclic anhydrides of the following structures:

9. The method according to claim 7 or 8, characterized in that: The alkylene oxide is selected from any one of the alkylene oxides of the following structures:

10. The method according to any one of claims 7 to 9, characterized in that: The number average molecular weight of the polyester is ≥3.0 kg / mol, preferably 3.0-100.0 kg / mol; and / or the molecular weight distribution of the polyester is ≤1.3, preferably 1.1-1.3.

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