A heterocyclic polyol acid compound, a preparation method and application thereof

Abstract

The application discloses a heterocyclic polyol acid compound and a preparation method and application thereof. The heterocyclic polyol acid compound has a structure shown in formula I, wherein Y comprises a substituted or unsubstituted heterocyclic group, R1 and R2 are independently selected from a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, and X comprises oxygen or sulfur. The heterocyclic polyol acid compound contains hydroxyl / mercapto groups, so that the compound can be used as a polyurethane chain extender, contains carboxylic acid groups, so that the compound can be used to prepare waterborne polyurethane by salification, and contains amide bonds, so that the synthesized polyurethane can have intermolecular hydrogen bonds, and the mechanical properties of the polyurethane are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic chemistry, and particularly relates to a heterocyclic polyol acid compound and a preparation method and application thereof. BACKGROUND

[0002] Polyurethane is one of the most widely used polymer materials at present. Due to its high wear resistance, high flexibility, strong bonding strength and excellent chemical resistance, it can meet the needs of various applications and has been widely used in the fields of coatings, home appliances, automobiles, buildings and the like. However, the traditional polyurethane uses a large amount of organic solvents in the preparation process, resulting in that the final product has high toxicity and strong pollution. With the strengthening of human environmental protection consciousness, the development of safe, non-toxic, solvent-free and green polyurethane has become a development trend.

[0003] Waterborne polyurethane has been paid more and more attention due to its green environmental protection performance and has a wide application prospect. In the preparation process of waterborne polyurethane, isocyanate, polyol, chain extender, salt forming agent and other additives are used. The chain extender plays an important role in the synthesis of polyurethane. Different functional group structures of the chain extender can lead to the innovation of polyurethane materials. Therefore, the in-depth research on the chain extender has become one of the popular attention directions of polyurethane materials. SUMMARY

[0004] To solve all or part of the above technical problems, the application provides the following technical scheme:

[0005] The main purpose of the application is to provide a heterocyclic polyol acid compound, which has the structure shown in formula I

[0006]

[0007] In the formula, Y includes a substituted or unsubstituted heterocyclic group, R1 and R2 are independently selected from a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, and X includes oxygen or sulfur. The substituted or unsubstituted alkyl group can be a straight-chain alkyl group or a branched-chain alkyl group.

[0008] The above technical scheme has the beneficial effects that the presence of oxygen, sulfur and nitrogen atoms in the heterocyclic group forms intermolecular hydrogen bonds, which is beneficial to improve the mechanical properties of polyurethane when the heterocyclic group is used in the synthesis of polyurethane. At the same time, the rigid structure of the heterocyclic group can further improve the mechanical properties of polyurethane.

[0009] In some embodiments, the heterocyclic polyol acid compound, Y comprises a nitrogen heterocycle, an oxygen heterocycle, or a sulfur heterocycle. Preferably, Y comprises a furan group, a tetrahydrofuran group, a pyrrole group, a pyridine group, a piperidine group, a thiophene group, an imidazole group, or a pyrazine group. More preferably, Y comprises a 2,5-furan group, a 2,5-tetrahydrofuran group, a 2,5-pyrrole group, or a 2,5-thiophene group.

[0010] In some embodiments, the heterocyclic polyol acid compound, R1, R2 are independently selected from a substituted or unsubstituted C1-C6 linear or branched alkyl group, or a substituted or unsubstituted aromatic ring. Further, R1, R2 are independently selected from a C1-C6 linear or branched alkyl group, or a substituted or unsubstituted phenyl group.

[0011] Preferably, R1, R2 are independently selected from a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a phenyl ring, or a phenethyl group.

[0012] A second object of the present application is to provide a method for preparing a heterocyclic polyol acid compound, the method comprising: subjecting a heterocyclic compound and a compound M to an amidation reaction, the heterocyclic compound having at least two substitution chains on a heterocyclic group thereof, and each of the substitution chains having at least one active group, the compound M containing an amino group and a carboxyl group, and further containing a hydroxyl group and / or a mercapto group, and at least one amino group of the compound M being subjected to the amidation reaction with the active group.

[0013] In some embodiments, the compound M has a structure as shown in Formula II:

[0014]

[0015] wherein R comprises a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and X comprises oxygen or sulfur.

[0016] In some preferred embodiments, the compound M comprises at least one of 2-amino-4-hydroxybenzoic acid, 4-amino-3-hydroxybenzoic acid, 2-amino-3-p-hydroxyphenylpropionic acid, 2-amino-3-hydroxypropionic acid, 2-amino-3-mercapto propionic acid, and 2-amino-3-hydroxybutyric acid. The compound M can be biologically derived, and has the characteristics of non-toxicity, good biocompatibility, and biodegradability.

[0017] In some embodiments, the heterocyclic compound has a structure as shown in Formula III,

[0018] R4-Y-R3

[0019] III

[0020] wherein Y comprises a substituted or unsubstituted heterocyclic group, and R3, R4 are independently selected from an ester group or an acyl chloride group.

[0021] In some preferred embodiments, Y comprises a furan group, a tetrahydrofuran group, a pyrrole group, a pyridine group, a piperidine group, a thiophene group, an imidazole group, or a pyrazine group. More preferably, the heterocyclic compound comprises at least one of 2,5-pyrrole dicarboxylic dichloride, 2,5-tetrahydrofuran dicarboxylic dichloride, 2,5-furan dicarboxylic dichloride, 2,5-thiophene dicarboxylic dichloride, 4,6-pyrimidine dicarboxylic dichloride, and 2,6-pyridine dicarboxylic dichloride.

[0022] Further, the preparation method comprises uniformly dispersing the compound M and the heterocyclic compound in a solution to form a mixed reaction solution for the amidation reaction.

[0023] Further, the preparation method specifically comprises uniformly dispersing the heterocyclic compound and the compound M in a solvent to form a mixed reaction solution, adjusting the pH of the mixed reaction solution to 7-8.5, and performing the amidation reaction at a temperature of 0-50°C to obtain the heterocyclic polyol acid compound. The solvent comprises, but is not limited to, a combination of one or more of water or an organic solvent, an ionic liquid, and the like non-aqueous solvent. For example, the organic solvent can be selected from at least one of a monohydric alcohol, an ether, a ketone, a halogenated hydrocarbon, a nitrogen compound, and a sulfur compound.

[0024] In some preferred embodiments, the heterocyclic compound is uniformly dispersed in a first solvent to form a solution A, the compound M is uniformly dispersed in a second solvent to form a solution B, and the solution A and the solution B are uniformly mixed to obtain the mixed reaction solution; the first solvent and the second solvent are independently selected from at least one of water, chloroform, dichloroethane, carbon tetrachloride, ethanol, THF (tetrahydrofuran), acetone, dichloromethane, DMF (N,N-dimethylformamide), and DMSO (dimethyl sulfoxide).

[0025] In some embodiments, the molar ratio of the heterocyclic compound to the compound M in the mixed reaction solution is 1:2-1:10. Preferably, the molar ratio of the heterocyclic compound to the compound M is 1:2-1:4.

[0026] In some embodiments, the reaction time of the amidation reaction is 1-10 h.

[0027] In some embodiments, after the amidation reaction is completed, the reaction product is subjected to post-treatment, and the post-treatment comprises first adjusting the pH of the reaction product to 4-5 using an acid, and then purifying.

[0028] In some embodiments, the amidation reaction can be carried out in the presence of an auxiliary agent or the like. Illustratively, the auxiliary agent can include a catalyst or the like. The catalyst includes, but is not limited to, one or more of triethylamine, pyridine, sodium ethoxide, and sodium carbonate.

[0029] In some embodiments, the entire synthesis reaction of the heterocyclic polyol acid compound can be carried out in one reaction vessel, i.e., by one-pot reaction synthesis.

[0030] A third object of the present application is to provide a heterocyclic polyol acid compound prepared by the preparation method described in the above technical solution.

[0031] A fourth object of the present application is to provide a derivative of any one of the above-mentioned heterocyclic polyol acid compounds, which includes at least one of a salt, an ester, and an amide.

[0032] A fifth object of the present application is to provide the use of the heterocyclic polyol acid compound in the above technical solution in the preparation of a polyurethane chain extender or as a polyurethane chain extender.

[0033] A sixth object of the present application is to provide a synthesis method of a waterborne polyurethane, comprising: reacting a mixed reaction system comprising isocyanate, polyol, solvent, and chain extender to obtain a waterborne polyurethane; wherein the chain extender comprises the heterocyclic polyol acid compound of any one of the above technical solutions.

[0034] Compared with the prior art, the present application has at least the following technical effects:

[0035] (1) The present application provides a heterocyclic polyol acid compound containing hydroxyl / mercapto, carboxylic acid group, and heterocyclic group, wherein the hydroxyl / mercapto enables the compound to be used as a polyurethane chain extender, the carboxylic acid group can be salted to increase the solubility of the polyurethane in water, and the rigid structure of the heterocyclic group and the intermolecular hydrogen bond formed by the amide bond in the structure of the heterocyclic polyol acid compound can improve the mechanical properties of the polyurethane.

[0036] (2) The novel heterocyclic polyol acid compound is semi / full biobased, has the advantages of non-toxicity, good biocompatibility, and biodegradability. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0038] Figure 1 Figure 1 is a nuclear magnetic resonance chart of a heterocyclic polyol acid compound prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0039] The technical solutions of the present application will be described in detail below with specific examples, so that those skilled in the art can better understand and implement the technical solutions of the present application. The specific functional details disclosed herein should not be interpreted as limiting, but only as a basis for the claims and for teaching those skilled in the art to employ the representative basis of the present application in different ways in any appropriate detailed embodiment.

[0040] Example 1:

[0041] 15 g of 2-amino-3-p-hydroxyphenylpropionic acid was weighed and dissolved in water, and the pH was adjusted to 8.0-8.5; 4.0 g of 2,5-pyrrole dicarboxylic acid chloride was dissolved in chloroform;

[0042] The 2,5-pyrrole dicarboxylic acid chloride solution was added dropwise to the 2-amino-3-p-hydroxyphenylpropionic acid solution at 10-15°C, and the pH was maintained between 8.0-8.5, and after the dropwise addition was completed, the reaction was continued for 2 h; after the reaction was completed, the reaction product was neutralized to a pH of about 5 using acid, and then purified using a silica gel column to obtain the product, with a yield of 68%.

[0043] 1 The H NMR data is δ 12.86 (s, 2H), 12.38 (s, 1H), 9.36 (s, 2H), 9.06 (s, 2H), 7.71 (s, 2H), 9.96 (d, 2H), 6.68 (d, 2H), 4.72 (t, 2H), 3.12 (m, 4H).

[0044] The product structure is as follows:

[0045]

[0046] Example 2:

[0047] 10 g of 2-amino-5-hydroxybenzoic acid was dissolved in an alkaline aqueous solution, and the pH was controlled at 7.5±0.5; 4.2 g of 2,5-furan dicarboxylic acid chloride was dissolved in dichloroethane;

[0048] The acid chloride solution was slowly added dropwise to the 2-amino-5-hydroxybenzoic acid solution at 15±5°C, and the pH was maintained at 7.5-8.0 using pyridine, and after the dropwise addition was completed, stirring was continued for 2 h; after the reaction was completed, the upper aqueous solution was taken, and neutralized to a pH of 4-5 using hydrochloric acid, and then purified using a silica gel column to obtain the product, with a yield of 69%.

[0049] The NMR spectrum of the product is shown in Figure 1 1 H NMR data is δ 13.08 (s, 2H), 12.05 (s, 2H), 9.43 (s, 2H), 8.48 (d, 2H), 7.66 (d, 4H), 7.23 (dd, 2H).

[0050] The structure of the product is as follows:

[0051]

[0052] Example 3:

[0053] Take 20g 2-amino-3-mercapto propionic acid and dissolve it in water, adjust the pH to 8.0-8.5; take 10.5g 2, 5-thiophene dicarboxylic acid chloride and dissolve it in dichloroethane;

[0054] At 10±5°C, the 2, 5-thiophene dicarboxylic acid chloride solution is added dropwise to the 2-amino-3-mercapto propionic acid solution, and sodium carbonate is used to maintain the pH at 8.0-8.5, and after the dropwise addition is completed, the reaction is continued for 3h; after the reaction is completed, the reaction product is adjusted to pH 4-4.5 with acid, and then purified using a silica gel column to obtain the product, with a yield of 43%.

[0055] 1 H NMR data is δ 12.45 (s, 2H), 8.78 (s, 2H), 8.45 (s, 2H), 4.78 (t, 2H), 3.15 (m, 4H), 1.43 (s, 2H).

[0056] The structure of the product is as follows:

[0057]

[0058] Example 4:

[0059] Take 15g 2-amino-3-hydroxy propionic acid and dissolve it in water, adjust the pH to 7.5-8.0; take 7.8g 2, 5-tetrahydrofuran dimethyl ester and dissolve it in carbon tetrachloride;

[0060] At room temperature, the 2, 5-tetrahydrofuran dimethyl ester solution is added dropwise to the 2-amino-3-hydroxy propionic acid solution, and triethylamine is used to maintain the pH at 7.0-8.0, and after the dropwise addition is completed, the reaction is continued for 3h; after the reaction is completed, the pH of the reaction product is adjusted to 4.5-5.0 with acid, and then purified using a silica gel column to obtain the product, with a yield of 57%.

[0061] 1 ​H NMR data is δ 12.39 (s, 2H), 9.89 (s, 1H), 9.46 (s, 1H), 9.38 (s, 2H), 5.37 (s, 2H), 4.64 (m, 2H), 4.37 (d, 2H), 1.16 (d, 6H).

[0062] The product structure is:

[0063]

[0064] Example 5:

[0065] Take 20 g of 2-amino-3-hydroxybutyric acid and dissolve it in water, adjust the pH to 7.5-8.0; take 12 g of 4, 6-pyrimidine dicarboxylic acid chloride and dissolve it in carbon tetrachloride;

[0066] Under ice bath conditions, the 4, 6-pyrimidine dicarboxylic acid chloride solution is added dropwise to the 2-amino-3-hydroxybutyric acid solution, and the pH is maintained at 7.5-8.0, and after the dropwise addition is completed, the reaction is continued for 2 h; after the reaction is completed, the pH of the reaction product is adjusted to 4.0-4.5 with acid, and the product is obtained by silica gel column purification, with a yield of 68%.

[0067] 1 H NMR data is δ 12.39 (s, 2H), 9.89 (s, 1H), 9.46 (s, 1H), 9.38 (s, 2H), 5.37 (s, 2H), 4.64 (m, 2H), 4.37 (d, 2H), 1.16 (d, 6H).

[0068] The product structure is:

[0069]

[0070] Example 6:

[0071] Take 20 g of 2-amino-2-hydroxyacetic acid and dissolve it in water, adjust the pH to 8.0-8.5; take 9.6 g of 2, 6-pyridine dicarboxylic acid chloride and dissolve it in carbon tetrachloride;

[0072] Under ice bath conditions, the 2, 6-pyridine dicarboxylic acid chloride solution is added dropwise to the 2-amino-2-hydroxyacetic acid solution, and the pH is maintained at 7.5-8.0, and after the dropwise addition is completed, the reaction is continued for 2 h; after the reaction is completed, the pH of the reaction product is adjusted to 4.0-4.5 with acid, and the product is obtained by silica gel column purification, with a yield of 56%.

[0073] 1HNMR data is δ 12.23 (s, 2H), 10.38 (s, 2H), 8.80 (d, 2H), 8.56 (t, 1H), 6.57 (s, 2H), 4.12 (s, 2H).

[0074]

[0075] Example 7:

[0076] The heterocyclic polyol acid compound obtained in Example 2 is used as a chain extender in the synthesis of polyurethane:

[0077] 50 g of polytetrahydrofuran (number average molecular weight 1000), 20.8 g of isophorone diisocyanate, 80 ml of acetone are weighed and heated to 70°C for 3h, then 6.53 g of the chain extender in Example 2 is added, the temperature is raised to 100°C for 5h, the temperature is lowered to 50°C, 3.5 g of triethylamine is added for neutralization, 200 g of water is added and stirred for 30 min, then the acetone is removed by distillation under reduced pressure, and an aqueous polyurethane is obtained.

[0078] A sample is prepared, dried, and tested by a universal testing machine to have a tensile strength of 29.3 MPa, and the aqueous polyurethane is successfully prepared, indicating that the product in Example 2 can be used as a polyurethane chain extender.

[0079] Comparative Example 1:

[0080] Comparative Example 1 and Example 1 only differ in that the chain extender used in Example 7 is replaced by dimethylol propionic acid, and the other operation steps are consistent with Example 7. A comparative sample is prepared by the same steps as Example 7, and its tensile strength is 21.6 MPa.

[0081] It can be seen that the chain extender prepared in the present application provides more intermolecular hydrogen bonds due to the presence of amide bonds, and based on the rigid structure of the heterocyclic group, the mechanical properties of the synthesized polyurethane can be improved.

[0082] Aspects, embodiments, features, and examples of the present application should be considered illustrative in all aspects and are not intended to limit the present application, and the scope of the present application is defined only by the claims. Other embodiments, modifications, and uses will be apparent to those skilled in the art without departing from the spirit and scope of the claimed application.

[0083] In addition, the applicant of the present application has also carried out tests with other raw materials, process operations, process conditions described in the present specification with reference to the foregoing examples, and all have obtained relatively ideal results.

[0084] While the present application has been described with reference to the illustrative embodiments, those with ordinary skill in the art will understand that various other changes, omissions, and / or additions can be made thereto and still be encompassed by the application. Further, many modifications can be made to adapt a particular situation or material to the teachings of the application without departing from its scope. Therefore, the scope of the application is intended to embrace all such changes, omissions, and / or additions as fall within the scope and spirit of the application. Further still, unless expressly stated to the contrary, any use of the term "first", "second", etc., herein does not denote any ordinal, or importance, but rather the terms "first", "second", etc., are merely used to distinguish one element from another.

Claims

1. A heterocyclic polyol acid compound characterized by: It has a structure as shown in formula I-1, I-2, I-3, I-4 or I-5: 。 2. The method of producing a heterocyclic polyol acid compound according to claim 1, characterized by, It comprises: The heterocyclic compound and the compound M are uniformly dispersed in a solvent to form a mixed reaction solution, and the pH of the mixed reaction solution is adjusted to 7-8.5, and the amidation reaction is carried out at a temperature of 0-50℃ to obtain the heterocyclic polyol acid compound. The heterocyclic compound is selected from at least one of 2,5-pyrrole dicarboxylic chloride, 2,5-tetrahydrofuran dimethyl ester, 2,5-furan dicarboxylic chloride, 4,6-pyrimidine dicarboxylic chloride, and 2,6-pyridine dicarboxylic chloride; and the compound M is selected from at least one of 2-amino-4-hydroxybenzoic acid, 4-amino-3-hydroxybenzoic acid, 2-amino-3-p-hydroxyphenylpropionic acid, 2-amino-3-hydroxypropionic acid, and 2-amino-3-hydroxybutyric acid.

3. The method for preparing heterocyclic polyol acid compounds according to claim 2, characterized in that: The heterocyclic compound is uniformly dispersed in a first solvent to form solution A, and the compound M is uniformly dispersed in a second solvent to form solution B, and the solution A and the solution B are uniformly mixed to obtain the mixed reaction solution; the first solvent and the second solvent are independently selected from at least one of water, chloroform, dichloroethane, carbon tetrachloride, ethanol, tetrahydrofuran, acetone, dichloromethane, N,N-dimethylformamide, and dimethyl sulfoxide.

4. The method for preparing heterocyclic polyol acid compounds according to claim 2, characterized in that: In the mixed reaction solution, the molar ratio of the heterocyclic compound to the compound M is 1:2-1:

10.

5. The method for preparing heterocyclic polyol acid compounds according to claim 4, characterized in that: The molar ratio of the heterocyclic compound to the compound M is 1:2-1:

4.

6. The method for preparing a heterocyclic polyol acid compound according to claim 2, characterized by: The reaction time of the amidation reaction is 1-10 h.

7. The method for preparing heterocyclic polyol acid compounds according to claim 2, characterized in that: After the amidation reaction is completed, the reaction product is subjected to post-treatment, and the post-treatment comprises: first adjusting the pH of the reaction product to 4-5 using an acid, and then purifying.

8. Use of the heterocyclic polyol acid compound of claim 1 in the preparation of a polyurethane chain extender or as a polyurethane chain extender.

9. Use according to claim 8, characterized in that, The use is: reacting a mixed reaction system comprising isocyanate, polyol, solvent and chain extender to obtain a waterborne polyurethane; wherein the chain extender comprises the heterocyclic polyol acid compound of claim 1.

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