Polymer containing ester-imide structural unit and preparation method thereof

Abstract

The invention discloses a polymer and a preparation method thereof. The polymer comprises an ester-imide structural unit as shown in a formula (I) and / or (II) and an optional structural unit as shown in a formula (III) and / or (IV) and / or (V) and / or (VI). The polymer disclosed by the invention has the properties of polyester and polyimide, is simple in preparation process, green and efficient, and has an industrial application prospect. # imgabs0 #

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials and chemical engineering, and in particular to a polymer and a preparation method thereof. The polymer comprises an ester-imide structural unit. Background Art

[0002] In the face of the increasingly serious energy crisis and environmental pollution, the development of renewable resources has become a general trend. With the rapid growth of human demand for degradable polymer materials and high-performance materials, the development of polymers derived from renewable resources has become an indispensable choice. With the rapid development of biotechnology, not only can renewable biomass resources be used to manufacture chemicals with the same structure as those derived from traditional petrochemical processes, but they can also be directly used as alternative monomers for the synthesis of polymers, such as ethylene glycol, 1,4-butanediol, ethylene, phenol, etc.; novel structural compounds can also be obtained for the development of new polymers, such as vanillin, furandicarboxylic acid, 2,5-pyridinedicarboxylic acid, amino acids, amino alcohols, etc. The novel structure gives polymer materials special properties and provides options for potential applications.

[0003] Polyester is a type of polymer material containing ester bonds in the repeating unit of the polymer, which is widely used in chemical fiber, packaging industry, electronic appliances, medical and health care, construction, automobile and other fields. At present, only polybutylene adipate / terephthalate (PBAT), polylactic acid (PLA), polybutylene succinate (PBS), polyhydroxyalkanoic acid (PHA) and others are considered to be degradable polyesters, which are not enough to meet the demand for degradable and high-performance polyesters in social development.

[0004] At present, the industrial polyester synthesis method usually adopts the condensation polymerization of dibasic acid and diol, and obtains polyester products with different properties by adjusting the structure of dibasic acid and diol, such as aromatic polyester, which contains aromatic rings in its structure, so the polyester is relatively rigid, has good mechanical properties and thermal stability; aliphatic polyester, which contains flexible fatty chains in its structure, has good processing properties; aromatic-aliphatic polyester, which can obtain polyester materials with both rigidity and flexibility by adjusting the comonomer. However, the synthesis process of industrial polyester inevitably involves the use of catalysts, the regulation of the ratio of raw material monomers, the occurrence of side reactions, and the limited molecular weight of the prepared polymer. Therefore, a method for synthesizing polyester without catalyst has been developed. For example, CN110790906A and CN112831033B disclose a method for synthesizing polyester without catalyst using an excess molar ratio of cyclic dicarboxylic acid or its cyclic anhydride.

[0005] Polyimide broadly refers to a class of polymer materials containing an imide ring structure in the polymer repeating unit. It has excellent mechanical properties, high and low temperature resistance, chemical stability and dielectric properties, and is widely used in aerospace, microelectronics, liquid crystal display and other fields. Polyimide is considered to be one of the polymer materials with the best comprehensive performance, and functionalized polyimide has attracted much attention. Traditional polyimide has poor processing performance due to its high glass transition temperature and difficulty in solubility in common organic solvents. Its film products are usually prepared by preparing polyamic acid solution and performing imidization, dehydration and cyclization at high temperature. Therefore, the development of new processes and new materials for the synthesis of polyimide has important research value and significance.

[0006] Polyesterimide is a new type of polymer material, which contains both ester bonds and imide ring structures in its main chain structure, and has the properties of both polyester and polyimide. The method of synthesizing polyesterimide by one-pot method of the present invention has simple process, green and environmental protection, and excellent comprehensive material performance, which has not been reported at home and abroad. Summary of the invention

[0007] The object of the present invention is to provide a polymer and a preparation method thereof, wherein the polymer comprises an ester-imide structural unit, and the polymer can be used in the fields of engineering plastics, degradable plastics, etc., has a simple preparation process, less pollution, easy operation, excellent comprehensive material performance, and has industrial prospects.

[0008] In one aspect of the present invention, a polymer is provided, comprising an ester-imide structural unit of formula (I) and / or (II), and optionally a structural unit of formula (III) and / or (IV) and / or (V) and / or (VI),

[0009]

[0010]

[0011] in:

[0012] R1 is a residue of a diol containing an amino group, preferably at least one of a trivalent alkyl group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a trivalent alkyl-aryl-alkyl group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro,

[0013] R2 is an easily cyclizable dibasic acid residue, preferably at least one of an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms, an alkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an arylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a heteroarylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged ring group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro,

[0014] R3 is different from R2 and is a residue of any dibasic acid, preferably at least one of an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms, an alkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an arylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a heteroarylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged ring group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro,

[0015] R4 is at least one of an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an -alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkylene group, an alkylene group, a polyether segment or an alkylene group interrupted by one or more N atoms.

[0016] In one embodiment of the present invention, R1 is a residue of a diol containing an amino group, preferably a trivalent alkyl group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a trivalent alkyl-aryl-alkyl group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro. The trivalent alkyl-aryl-alkyl group is preferably a trivalent C1-C 10 Alkyl-C6-C 10 Aryl-C1-C 10 The alkyl group is preferably a trivalent C1-C5 alkyl-C6-C8 aryl-C1-C5 alkyl group, and more preferably a trivalent C1-C3 alkyl-C6-C8 aryl-C1-C3 alkyl group.

[0017] In the context of the present invention, halogen may be fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine. The alkyl group as a substituent may be a C1-C8 alkyl group, preferably a C1-C6 alkyl group, more preferably a C1-C3 alkyl group.

[0018] In a preferred embodiment of the present invention, R1 is selected from at least one of the following structures:

[0019]

[0020] In the above formula, * indicates the bonding site to the O atom, and ** indicates the bonding site to the N atom.

[0021] In one embodiment of the present invention, R2 is a residue of an easily cyclized dibasic acid, preferably an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms, an alkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an arylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a heteroarylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged ring group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro. The alkylene group may be C2-C 10 The alkylene group is preferably a C2-C6 alkylene group, more preferably a C2-C5 alkylene group, and most preferably an ethylene group, 1-methylethylene, 1,1-dimethylethylene, 1,2-dimethylethylene, 1,1,2,2-tetramethylethylene, 1-phenylethylene, 1-benzylethylene, 1,1-diphenylethylene, 1,1-dibenzylethylene, 1,2-diphenylethylene, 1,2-dibenzylethylene, propylene, 1-methylpropylene, 2-methylpropylene, 1,1-dimethylpropylene, 1,2-dimethylpropylene, 2,2-dimethylpropylene, 1,3-dimethylpropylene, 1-phenylpropylene, 2-phenylpropylene, 1,2-diphenylpropylene, 2,2-diphenylpropylene or 1,3-diphenylpropylene. The alkenylene group may be a C2-C6 alkylene group. 10Alkenylene, preferably C2-C6 alkenylene, more preferably C2-C3 alkenylene, most preferably vinylene, 1-methylvinylene, 1,2-dimethylvinylene or propenylene. Alkylene which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms may be interrupted by one or more O atoms, such as 1-3 oxygen atoms, such as 2-oxa-1,3-ethylene. The cycloalkylene may be C3-C8 cycloalkylene, preferably C4-C6 cycloalkylene, most preferably cyclobutylene (e.g. 1,2-cyclobutylene) or cyclohexylene (e.g. 1,6-cyclohexylene). The cycloalkenylene may be C4-C8 cycloalkenylene, preferably C4-C6 cycloalkenylene, most preferably 3-cyclohexene-1,6-diyl. The arylene may be C6-C 10 Arylene, preferably phenylene, such as 1,6-phenylene. The heteroarylene may be a 5-18 membered heteroaryl group containing one or more, preferably 1-3, such as 1 or 2 heteroatoms selected from N, S and O, examples of which include furanylene (such as 2,3-furanyl or 3,4-furanyl), pyridinylene (such as 2,3-pyridinyl or 3,4-pyridinyl), thienylene, pyrrolylene, imidazolylene, pyrazolylene, pyrazinylene or pyrimidinylene, preferably furanylene or pyridinylene. The bridging ring group may be norbornene.

[0022] In one embodiment of the present invention, R3 is different from R2 and is any dibasic acid residue, for example, it can be the residue of the easily cyclizable dibasic acid described above for R2; or R3 can be the residue of a dibasic acid that is not easily cyclizable, and the dibasic acid that is not easily cyclizable can be, for example, terephthalic acid, 2,5-furandicarboxylic acid, oxalic acid, malonic acid, 1,6-hexanedicarboxylic acid, 1,10-decanedioic acid, 1,18-octadecane dioic acid. Preferably, R3 is an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms, an alkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an arylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a heteroarylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged ring group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro. The alkylene group may be C2-C 10The alkylene group is preferably a C2-C6 alkylene group, more preferably a C2-C5 alkylene group, and most preferably an ethylene group, 1-methylethylene, 1,1-dimethylethylene, 1,2-dimethylethylene, 1,1,2,2-tetramethylethylene, 1-phenylethylene, 1-benzylethylene, 1,1-diphenylethylene, 1,1-dibenzylethylene, 1,2-diphenylethylene, 1,2-dibenzylethylene, propylene, 1-methylpropylene, 2-methylpropylene, 1,1-dimethylpropylene, 1,2-dimethylpropylene, 2,2-dimethylpropylene, 1,3-dimethylpropylene, 1-phenylpropylene, 2-phenylpropylene, 1,2-diphenylpropylene, 2,2-diphenylpropylene or 1,3-diphenylpropylene. The alkenylene group may be a C2-C6 alkylene group. 10 Alkenylene, preferably C2-C6 alkenylene, more preferably C2-C3 alkenylene, most preferably vinylene, 1-methylvinylene, 1,2-dimethylvinylene or propenylene. Alkylene which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms may be interrupted by one or more O atoms, such as 1-3 oxygen atoms, such as 2-oxa-1,3-ethylene. The cycloalkylene may be C3-C8 cycloalkylene, preferably C4-C6 cycloalkylene, most preferably cyclobutylene (e.g. 1,2-cyclobutylene) or cyclohexylene (e.g. 1,6-cyclohexylene). The cycloalkenylene may be C4-C8 cycloalkenylene, preferably C4-C6 cycloalkenylene, most preferably 3-cyclohexene-1,6-diyl. The arylene may be C6-C 10 Arylene, preferably phenylene, such as 1,6-phenylene. The heteroarylene may be a 5-18 membered heteroaryl group containing one or more, preferably 1-3, such as 1 or 2 heteroatoms selected from N, S and O, examples of which include furanylene (such as 2,3-furanyl or 3,4-furanyl), pyridinylene (such as 2,3-pyridinyl or 3,4-pyridinyl), thienylene, pyrrolylene, imidazolylene, pyrazolylene, pyrazinylene or pyrimidinylene, preferably furanylene or pyridinylene. The bridging ring group may be norbornene.

[0023] R4 is an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an -alkylene-cycloalkylene-alkylene-, a polyether segment, or an alkylene group which is interrupted by one or more N atoms. The alkylene group may be C2-C 30 Alkylene, preferably C2-C 25 Alkylene, more preferably C2-C 20Alkylene, such as ethylene, isopropyl (such as 1,3-propylene), butylene (such as 1,4-butylene), pentylene (such as 1,5-pentylene), hexylene (such as 1,6-hexylene), heptylene (such as 1,7-heptylene), octylene (such as 1,8-octylene), decylene (such as 1,10-decylene), octadecylene (such as 1,18-octadecylene). The cycloalkylene may be cyclopropylene, cyclobutylene, cyclopentylene or cyclohexylene. The polyether segment may be a polyethylene glycol segment, a polypropylene glycol segment or a polytetrahydrofuran diol segment, each of which may contain 2-1000 repeating structural units, preferably 2-500 repeating structural units, more preferably 2-250 repeating structural units, and most preferably 2-100 repeating structural units. The chain of the alkylene group interrupted by one or more N atoms may be interrupted by 1-10 N atoms, more preferably 1-5 N atoms, more preferably 1-3 N atoms, and most preferably 1 N atom; wherein the N atoms are substituted by alkyl groups, such as methyl or ethyl. Preferably, R4 is at least one of the following structural formulas,

[0024]

[0025]

[0026] wherein * is a connection site with other parts of the molecule, x is an integer of 2-20, preferably an integer of 2-18, m is an integer of 2-8, preferably an integer of 2-6, more preferably an integer of 2-4, y is an integer of 2-1000, preferably an integer of 2-500, more preferably an integer of 2-250, and most preferably an integer of 2-100.

[0027] In the polymer of the present invention, the number of structural units of formula (I), (II), (III), (IV), (V) and (VI) is not particularly limited and may be a number of 0-1000, preferably 0-500, more preferably 0-250, for example 5, 10, 15, 20, 25, 30, 35, provided that the sum of the numbers of structural units of formula (I) and (II) is at least 5, preferably at least 10, more preferably at least 15. Due to the characteristics of polymers, this number is an average degree of polymerization, so it may be an integer or a fraction.

[0028] In one embodiment of the present invention, in one aspect of the present invention, the polymer of the present invention comprises ester-imide structural units of formula (I) and / or (II), and optionally structural units of formula (III) and / or (IV) and / or (V) and / or (VI); preferably consists of ester-imide structural units of formula (I) and / or (II), and optionally structural units of formula (III) and / or (IV) and / or (V) and / or (VI). In another embodiment of the present invention, the polymer of the present invention comprises structural units of formula (I) and optionally structural units of formula (III), preferably consists of structural units of formula (I) and optionally structural units of formula (III). In another embodiment of the present invention, the polymer of the present invention comprises structural units of formula (I), optionally structural units of formula (III), optionally structural units of formula (V) and optionally structural units of formula (VI), preferably consists of structural units of formula (I), optionally structural units of formula (III), optionally structural units of formula (V) and optionally structural units of formula (VI). In another embodiment of the present invention, the polymer of the present invention comprises structural units of formula (II) and optional structural units of formula (IV), preferably consists of structural units of formula (II) and optional structural units of formula (IV). In another embodiment of the present invention, the polymer of the present invention comprises structural units of formula (II), optional structural units of formula (IV), optional structural units of formula (V) and optional structural units of formula (VI), preferably consists of structural units of formula (II), optional structural units of formula (IV), optional structural units of formula (V) and optional structural units of formula (VI).

[0029] In a preferred embodiment of the present invention, the polymer of the present invention has the structural formula shown below:

[0030]

[0031] wherein m1 is 5-1000, preferably 10-500, more preferably 15-200; m2 is 0-100, preferably 0-25, more preferably 0-10; m3 is 5-1000, preferably 10-500, more preferably 15-200; m4 and m5 are each independently 0-1000, preferably 10-500, more preferably 15-200, provided that m3+m4 is at least 5, preferably m6 is a number of 0-100, preferably 0-25, more preferably 0-10, m7 is a number of 5-1000, preferably 10-500, more preferably 15-200; m8 and m9 are each independently a number of 0-1000, preferably 10-500, more preferably 15-200, provided that m8+m9 is a number of at least 5, preferably at least 10, more preferably at least 15, m 10 and m 11Each independently represents a number from 0 to 1000, preferably from 0 to 250, more preferably from 0 to 50; m 12 is a number ranging from 0 to 100, preferably from 0 to 25, more preferably from 0 to 10, m 13 is 5-1000, preferably 10-500, more preferably 15-200, m 14 and m 15 Each independently represents a number of 0-1000, preferably 0-250, more preferably 0-50.

[0032] The polymer of the present invention can be a random copolymer or a block copolymer, and it can have a number average molecular weight of 3000-500000Da, preferably 8000-200000Da, more preferably 10000-100000Da, and most preferably 12000-50000Da. The polymer of the present invention can have a weight average molecular weight of 6000-600000Da, preferably 9000-300000Da, more preferably 12000-120000Da, and most preferably 15000-80000Da. The polymer of the present invention can have a molecular weight distribution of 1.01-8.00, preferably 1.10-5.00, more preferably 1.15-3.00, and most preferably 1.20-2.00. The parameters are obtained by gel permeation chromatography (GPC) test.

[0033] In another aspect of the present invention, there is provided a method for preparing a polymer comprising an ester-imide structural unit of formula (I) and / or (II), and optionally a structural unit of formula (III) and / or (IV) and / or (V) and / or (VI),

[0034]

[0035]

[0036] Wherein R1, R2, R3 and R4 are as defined above, the method comprises:

[0037] The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and OH-R1(NH2)-OH, or a mixture of OH-R1(NH2)-OH and OH-R4-OH as a raw material to carry out esterification reaction, amidation reaction and imide cyclization reaction;

[0038] The second stage: in the absence of a catalyst or in the presence of a catalyst, HOOC-R2-COOH or HOOC-R3-COOH is added to further carry out esterification reaction and imide cyclization reaction to obtain a carboxyl-terminated prepolymer;

[0039] The third stage: in the absence of catalyst or in the presence of catalyst, remove cyclic anhydride and water to obtain high molecular weight polymer.

[0040] or,

[0041] The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and OH-R1(NH2)-OH, or a mixture of OH-R1(NH2)-OH and OH-R4-OH as a raw material to carry out esterification reaction, amidation reaction and imide cyclization reaction;

[0042] The second stage: adding HOOC-R2-COOH or HOOC-R3-COOH, further carrying out esterification reaction and imide cyclization reaction to obtain a carboxyl-terminated prepolymer, and then adding a catalyst and OH-R4-OH to react to obtain a hydroxyl-terminated prepolymer.

[0043] The third stage: in the presence of a catalyst, OH-R4-OH and water are removed to obtain a high molecular weight polymer.

[0044] The HOOC-R2-COOH is a dibasic acid that is easily cyclized, that is, a dibasic carboxylic acid that easily forms a cyclic anhydride in the absence of a catalyst or under a catalyst condition. Dibasic acids that are easily cyclized are known to those skilled in the art, for example, see CN110790906B. HOOC-R2-COOH may be selected from an alkanedicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkanedicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl interrupted by one or more O atoms, an alkenedicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen or alkyl, a cycloalkanedicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkenedicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an aromatic dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged cyclic dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro. Preferably, HOOC-R2-COOH can be selected from at least one of succinic acid, 2-methylsuccinic acid, 2-phenylsuccinic acid, 2-benzylsuccinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylsuccinic acid, 2,3-diphenylsuccinic acid, 1,2-cyclobutanedicarboxylic acid, 2,2,3,3-tetramethylsuccinic acid, methylmaleic acid, dimethylmaleic acid, phthalic acid, hexahydrophthalic acid, norbornene dicarboxylic acid, tetrahydrophthalic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 3-phenylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, diglycolic acid, 2,3-furandicarboxylic acid, 3,4-furandicarboxylic acid, 2,3-pyridinedicarboxylic acid, and 3,4-pyridinedicarboxylic acid. The cyclic anhydride of HOOC-R2-COOH can be preferably selected from succinic anhydride, 2-methylsuccinic anhydride, 2-phenylbutyric anhydride, 2-benzylsuccinic anhydride, 2,2-dimethylsuccinic anhydride, 2,3-dimethylsuccinic anhydride, 2,3-diphenylsuccinic anhydride, 1,2-cyclosuccinic anhydride, 2,2,3,3-tetramethylsuccinic anhydride, methylmaleic anhydride, dimethylmaleic anhydride, phthalic anhydride At least one of dihydrophthalic anhydride, hexahydrophthalic anhydride, nadic anhydride, tetrahydrophthalic anhydride, glutaric anhydride, 2-methylglutaric anhydride, 3-methylglutaric anhydride, 3-phenylglutaric anhydride, 2,2-dimethylglutaric anhydride, 3,3-dimethylglutaric anhydride and diglycolic anhydride, 2,3-furandicarboxylic anhydride, 3,4-furandicarboxylic anhydride, 2,3-pyridinedicarboxylic anhydride and 3,4-pyridinedicarboxylic anhydride.

[0045] The OH-R1(NH2)-OH is an amino-containing diol. The amino-containing diol can be selected from an alkanediolamine that is unsubstituted or substituted with a substituent selected from a halogen, an alkyl group or a nitro group, or an alkyl-aryl-alkyldiolamine that is unsubstituted or substituted with a substituent selected from a halogen, an alkyl group or a nitro group. Preferably, the amino-containing diol can be selected from at least one of 3-amino-1,2-propylene glycol, 2-amino-1,3-propylene glycol, 2-amino-1,3-butanediol, 2-amino-1,4-butanediol, 2-amino-1,5-pentanediol, 3-amino-1,5-pentanediol, 5-amino-1,3-benzenedimethanol and 2-amino-1,3-phenylenedimethanol.

[0046] The HOOC-R3-COOH can be any dibasic acid different from HOOC-R2-COOH, for example, it can be the easily cyclized dibasic acid described above for HOOC-R2-COOH; or it can be a dibasic acid that is not easily cyclized, such as terephthalic acid, 2,5-furandicarboxylic acid, oxalic acid, malonic acid, 1,6-hexanedicarboxylic acid, 1,10-decanedioic acid, and 1,18-octadecanedicarboxylic acid. Preferably, HOOC-R3-COOH can be selected from an alkane dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkane dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms, an alkene dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen or alkyl, a cycloalkane dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkene dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an aromatic dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged cyclic dicarboxylic acid which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro. Preferably, HOOC-R3-COOH can be selected from succinic acid, 2-methylsuccinic acid, 2-phenylsuccinic acid, 2-benzylsuccinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylsuccinic acid, 2,3-diphenylsuccinic acid, 1,2-cyclobutanediol, 2,2,3,3-tetramethylsuccinic acid, oxalic acid, malonic acid, 1,6-hexanediol, 1,10-decanedioic acid, 1,18-octadecanediol, maleic acid, methylmaleic acid, dioctanoic acid, 1,6-hexanedioic acid, 1,10-decanedioic acid, 1,18-octadecanediol, maleic acid, methylmaleic acid, dioctanoic acid, 1,2-cyclobutanediol, 2,2,3,3-tetramethylsuccinic acid, oxalic acid, malonic ... 1,2- At least one of methylmaleic acid, phthalic acid, hexahydrophthalic acid, nadic acid, tetrahydrophthalic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 3-phenylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, diglycolic acid, 2,3-furandicarboxylic acid, 3,4-furandicarboxylic acid, 2,3-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, terephthalic acid, and 2,5-furandicarboxylic acid.

[0047] The OH-R4-OH diol can be selected from alkylene glycols that are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, OH-alkylene-cycloalkylene-alkylene-OH that are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, polyether glycol, or alkylene glycols separated by one or more N atoms; preferably selected from at least one of alkylene glycols containing 2 to 18 carbon atoms, polyethylene glycol, polypropylene glycol, polytetrahydrofuran glycol, N-methyldiethanolamine, and N-ethyldiethanolamine. The OH-R4-OH diol can be preferably selected from at least one of ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,18-octadecanediol, polyethylene glycol, and 1,4-cyclohexanedimethanol.

[0048] The first and second stages are carried out in the absence of a catalyst or in the presence of a catalyst, preferably in the absence of a catalyst. If the third stage is to remove cyclic anhydrides, it can be carried out in the absence of a catalyst or in the presence of a catalyst; if the third stage is to remove glycols, it is carried out in the presence of a catalyst. The catalyst can be selected from at least one of aluminum chloride, ferric chloride, boron trifluoride, stannous chloride, stannous octoate, stannous isooctanoate, dibutyltin dilaurate, monobutyltin oxide, antimony trioxide, zinc oxide, isopropyl titanate, and tetrabutyl titanate. If used, the amount of the catalyst can be 1-2000ppm, preferably 10-1000ppm, based on the total weight of the reactants.

[0049] The excess molar ratio in the first stage refers to the molar ratio of (HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH) to (OH-R1(NH2)-OH, or a mixture of OH-R1(NH2)-OH and OH-R4-OH) of (1.01 to 10):1, preferably (1.5 to 4):1.

[0050] The reaction temperature of the amidation reaction, esterification reaction and imide cyclization reaction in the first stage and the second stage can be 60-300° C., preferably 100-250° C., and the reaction time can be 0.1-72 hours, preferably 3-24 hours.

[0051] The first stage can be carried out in air or inert atmosphere, for example, nitrogen or argon atmosphere. The second stage can be carried out in inert atmosphere, for example, nitrogen or argon atmosphere.

[0052] The prepolymer obtained in the second stage may have a number average molecular weight of 2000-10000Da, preferably 4000-8000Da, a weight average molecular weight of 2500-30000Da, preferably 5000-10000Da, and a molecular weight distribution of 1.01-5.00, preferably 1.10-4.00, more preferably 1.15-3.00, and most preferably 1.20-2.00.

[0053] In the third stage, the carboxyl or hydroxyl terminated prepolymer forms anhydride or diol through "biting back" at the end of the molecular chain and evaporates to obtain a high molecular weight polyester. The reaction temperature in the third stage can be 150-300°C, preferably 180-250°C, and the reaction time can be 6-72 hours, preferably 6-48 hours. The vacuum degree during decompression is less than 200Pa, preferably less than 100Pa. The third stage is carried out under reduced pressure. The purpose of reduced pressure is to separate small molecules with relatively low boiling points such as water, cyclic anhydrides or diols from the product system, promote the growth of polymer chains, and improve polymerization efficiency.

[0054] The first stage and the second stage of the polymer preparation method of the present invention comprise the reaction process shown in the following formula:

[0055]

[0056] The polymer of the present invention may have a number average molecular weight of 3000-500000Da, preferably 8000-200000Da, more preferably 10000-100000Da, most preferably 12000-50000Da. The polymer of the present invention may have a weight average molecular weight of 6000-600000Da, preferably 9000-300000Da, more preferably 12000-120000Da, most preferably 15000-80000Da. The polymer of the present invention may have a molecular weight distribution of 1.01-8.00, preferably 1.10-5.00, more preferably 1.15-3.00, most preferably 1.20-2.00. The parameters are obtained by gel permeation chromatography (GPC) test.

[0057] The polymers of the present invention can be synthesized using monomers of biological origin. As a characteristic of polymers synthesized using monomers of biological origin, the polymers of the present invention have a 14 C / 12 C ratio. As another alternative, the polymers of the present invention may also be synthesized using monomers of petroleum origin.

[0058] In one embodiment of the present invention, the polymer of the present invention can also be obtained by subjecting an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH to an amide-acid structure-containing diol as shown in formula (VII) to esterification and imide cyclization to obtain a carboxyl-terminated prepolymer, and then removing the cyclic anhydride and water, or reacting the prepolymer with OH-R4-OH to obtain a hydroxyl-terminated prepolymer, and then removing OH-R4-OH and water; or by subjecting an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH to an amide-acid structure-containing diol as shown in formula (VIII) to esterification to obtain a carboxyl-terminated prepolymer, and then removing the cyclic anhydride and water, or reacting the prepolymer with OH-R4-OH to obtain a hydroxyl-terminated prepolymer, and then removing OH-R4-OH and water:

[0059]

[0060] wherein R1, R2, R3 and R4 are as defined above.

[0061] Therefore, in another aspect of the present invention, the present invention relates to a process for preparing a polymer comprising ester-imide structural units of formula (I) and / or (II) and optionally structural units of formula (III) and / or (IV) and / or (V) and / or (VI),

[0062]

[0063]

[0064] Wherein R1, R2, R3 and R4 are as defined above, the method comprises:

[0065] The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an amide-acid structure represented by formula (VII) as raw materials, and performing an esterification reaction and an imide cyclization reaction to obtain a carboxyl-terminated prepolymer;

[0066] The second stage: removing the cyclic anhydride and water in the absence of a catalyst or in the presence of a catalyst to obtain a high molecular weight polymer; or

[0067] The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an amide-acid structure represented by formula (VII) as raw materials, performing an esterification reaction and an imide cyclization reaction to obtain a carboxyl-terminated prepolymer, and then adding a catalyst and reacting with OH-R4-OH to obtain a hydroxyl-terminated prepolymer,

[0068] The second stage: removing OH-R4-OH and water in the presence of a catalyst to obtain a high molecular weight polymer; or

[0069] The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an imide structure represented by formula (VIII) as raw materials, and performing an esterification reaction to obtain a carboxyl-terminated prepolymer;

[0070] The second stage: removing the cyclic anhydride and water in the absence of a catalyst or in the presence of a catalyst to obtain a high molecular weight polymer; or

[0071] The first stage: in the absence of a catalyst or in the presence of a catalyst, an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an imide structure represented by formula (VIII) are used as raw materials to carry out an esterification reaction to obtain a carboxyl-terminated prepolymer, and then a catalyst is added to react with OH-R4-OH to obtain a hydroxyl-terminated prepolymer.

[0072] The second stage: in the presence of a catalyst, OH-R4-OH and water are removed to obtain a high molecular weight polymer.

[0073] The specific reaction conditions are the same as those described above for the method using diolamine monomers.

[0074] The diol containing an amide-acid structure shown in formula (VII) can be synthesized by methods known in the art. Preferably, the diol containing an amide-acid structure shown in formula (VII) can be obtained by reacting an amino diol containing OH-R1(NH2)-OH with an acid anhydride of HOOC-R2-COOH in an organic solvent at room temperature under the action of a catalyst, and then acidifying with an acidifying agent.

[0075] Therefore, in another aspect of the present invention, the present invention relates to a method for preparing a diol containing an amide-acid structure shown in formula (VII), which comprises: reacting the corresponding OH-R1(NH2)-OH amino diol with the anhydride of HOOC-R2-COOH in water or an organic solvent in the presence of a catalyst, and then acidifying with an acidifying agent, wherein R1 and R2 are as defined above.

[0076] The organic solvent may be selected from esters such as ethyl acetate and butyl acetate; nitriles such as acetonitrile; amides such as N,N-dimethylformamide and N,N-dimethylacetamide; dimethyl sulfoxide; dioxane; ethers such as trimethyl glycerol and dimethyl sorbitol, etc. The catalyst may be selected from potassium carbonate, sodium carbonate, cesium carbonate, sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, disodium hydrogen phosphate, dipotassium hydrogen phosphate, triethylamine, triisopropylamine, trioctylamine, tetramethylguanidine, pyridine, piperidine, 1,8-diazacyclo[5,4,0]undecene-7, 1,5-diazabicyclo[4.3.0]non-5-ene, etc.

[0077] The acidifying agent can be selected from, for example, hydrochloric acid, phosphoric acid, boric acid, nitric acid, sulfuric acid, acetic acid, sodium dihydrogen phosphate, potassium dihydrogen phosphate, and the like.

[0078] The reaction may be carried out at a temperature of -20-100° C. Preferably, the reaction temperature is 0-50° C. The molar ratio of the amino-containing diol to the acid anhydride may be 1:5 to 5:1, preferably 1:2 to 2:1, and more preferably 1:1.

[0079] The diol containing an imide structure shown in formula (VIII) can be synthesized by methods known in the art. Preferably, the diol containing an imide structure shown in formula (VIII) can be obtained by reacting an amino diol containing OH-R1(NH2)-OH with an acid anhydride of HOOC-R2-COOH in an organic solvent in the presence of a catalyst.

[0080] Therefore, in another aspect of the present invention, the present invention relates to a method for preparing a diol containing an imide structure shown in formula (VIII), which comprises: reacting the corresponding OH-R1(NH2)-OH amino diol with the anhydride of HOOC-R2-COOH in water or an organic solvent in the presence of a catalyst, wherein R1 and R2 are as defined above.

[0081] The organic solvent may be selected from esters such as ethyl acetate and butyl acetate; nitriles such as acetonitrile; amides such as N,N-dimethylformamide and N,N-dimethylacetamide; dimethyl sulfoxide; dioxane; ethers such as trimethyl glycerol and dimethyl sorbitol, etc. The catalyst may be selected from potassium carbonate, sodium carbonate, cesium carbonate, sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, disodium hydrogen phosphate, dipotassium hydrogen phosphate, triethylamine, triisopropylamine, trioctylamine, tetramethylguanidine, pyridine, piperidine, 1,8-diazacyclo[5,4,0]undecene-7, 1,5-diazabicyclo[4.3.0]non-5-ene, etc.

[0082] The reaction may be carried out at a temperature of 0-200° C. Preferably, the reaction temperature is 80-150° C. The molar ratio of the amino-containing diol to the acid anhydride may be 1:5 to 5:1, preferably 1:2 to 2:1, and more preferably 1:1.

[0083] When HOOC-R2-COOH is succinic acid, the diol containing an imide structure represented by formula (VIII) is a structure represented by the following formula:

[0084]

[0085] It can be achieved through Obtained by hydrogenation of double bonds.

[0086] The hydrogenation conditions are selected from methods known in the art. Preferably, the double bond hydrogenation reaction can be carried out using Ru / C (5 wt% Ru loading) catalyst, tetrahydrofuran solvent, 10-100 bar hydrogen pressure, and room temperature reaction conditions.

[0087] The polymer material protected by the present invention has the following characteristics:

[0088] 1. The monomer raw materials are derived from biomass resources. For example, 3-amino-1,2-propanediol and 2-amino-1,3-propanediol can be derived from glycerol, and succinic acid can be obtained by biological fermentation. They are green polymer materials.

[0089] 2. The sources of raw materials are diverse, including amino diols, diols, easily cyclized dibasic acids, and dibasic acids with a wide range of selectivity.

[0090] 3. The polymer structure is diverse and has adjustable properties, and rigid aromatic structures or flexible aliphatic structures can be introduced.

[0091] 4. The polymer synthesized by the present invention has the properties of both polyester and polyimide, and has the properties of melt processing performance, high and low temperature resistance, etc.

[0092] 5. The polymerization process provided by the present invention is simple, green and environmentally friendly, has high polymerization efficiency, and has broad industrial application prospects.

[0093] The polymer of the invention can be degraded and used as degradable plastics. In addition, it can also be used in the fields of optoelectronic materials, engineering plastics, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0094] Figure 1 This is a comparison diagram of the H NMR spectra during the reaction process of Example 1.

[0095] Figure 2 This is the H-NMR spectrum of the prepolymer of Example 1.

[0096] Figure 3 This is the H NMR spectrum of the product removed under reduced pressure in Example 1.

[0097] Figure 4 This is the infrared spectrum of the target product prepared in Example 1.

[0098] Figure 5 This is the H NMR spectrum of the target product prepared in Example 1.

[0099] Figure 6 This is the NMR carbon spectrum of the target product prepared in Example 1.

[0100] Figure 7 This is the TGA test curve of the target product prepared in Example 1.

[0101] Figure 8 This is the DSC test curve of the target product prepared in Example 1.

[0102] Fig. 9 This is a comparison chart of the GPC test curves of the target products prepared in Examples 1, 15 and 16.

[0103] Fig.10 This is the H NMR spectrum of the target product prepared in Example 12.

[0104] Fig.11 This is a comparison chart of the GPC test curves of the target products prepared in Examples 2, 3, 4, 5, 9 and 11.

[0105] Fig.12 This is the H NMR spectrum of the target product prepared in Example 17.

[0106] Fig.13 This is the H NMR spectrum of the target product prepared in Example 22.

[0107] Fig.14 This is the H NMR spectrum of the target product prepared in Example 23.

[0108] Fig.15 This is the H NMR spectrum of the target product prepared in Example 27.

[0109] Fig.16This is the H NMR spectrum of the target product prepared in Example 28.

[0110] Fig.17 This is the NMR carbon spectrum of the target product prepared in Example 28.

[0111] Fig.18 This is the H NMR spectrum of the target product prepared in Example 29.

[0112] Fig.19 This is the NMR carbon spectrum of the target product prepared in Example 29.

[0113] Fig. 20 This is the H NMR spectrum of the target product prepared in Example 30.

[0114] Fig.21 This is the H NMR spectrum of the target product prepared in Example 31.

[0115] Fig. 22 This is the H NMR spectrum of the target product prepared in Example 32.

[0116] Fig.23 This is the H NMR spectrum of the target product prepared in Example 33.

[0117] Fig.24 This is the H NMR spectrum of the target product prepared in Example 34.

[0118] Fig.25 This is the H NMR spectrum of the target product prepared in Example 35. DETAILED DESCRIPTION

[0119] The following specific embodiments are helpful for understanding the present invention, but these embodiments do not limit the scope of the present invention.

[0120] Example 1

[0121]

[0122] 3-Amino-1,2-propanediol (40 mmol) and succinic acid (88 mmol) were added to a 150 mL three-necked flask, mechanically stirred, and heated to 180 ° C under nitrogen conditions to carry out esterification and imide cyclization reactions. In the initial stage of the reaction, water vapor can be observed at the outlet. The reaction was carried out for 16 hours to obtain a succinic acid-terminated prepolymer. Turn off the nitrogen, use an oil pump to evacuate the vacuum to less than 100 Pa, gradually heat up to 220 ° C, and the reaction is completed after 16 hours. During the reaction, white solids can be observed to be attached to the vacuum inlet. The number average molecular weight of the prepolymer obtained by gel permeation chromatography (GPC) test is 7575 Da, the weight average molecular weight is 9318 Da, and the molecular weight distribution is 1.23. The number average molecular weight of the final polycondensation product is 22311 Da, the weight average molecular weight is 29161 Da, and the molecular weight distribution is 1.31.

[0123] Figure 1 The comparison diagram of the H NMR spectrum during the reaction of this example is shown in Figure 1. Samples were taken at 10min, 30min, 60min, 120min, 180min, 240min, and 360min, and the H NMR spectrum was measured using DMSO-d6 as the solvent. The chemical shift of 7.8 to 7.9ppm represents the amide bond hydrogen proton peak in the reaction system. As the reaction time increases, the amide bond hydrogen proton peak gradually disappears during the reaction. Figure 2 The nuclear magnetic hydrogen spectrum of the prepolymer shows that the following reaction process exists during the reaction:

[0124]

[0125] Figure 2 This is the H NMR spectrum of the prepolymer. In the spectrum, the hydrogen proton chemical shift peak of the carboxyl group can be clearly observed, while the hydrogen proton chemical shift peak of the amide group and the hydrogen proton chemical shift peak of 3-amino-1,2-propanediol are not observed, indicating that 3-amino-1,2-propanediol is completely reacted to obtain a succinic acid-terminated prepolymer.

[0126] Figure 3 The H-NMR spectrum of the white solid attachment shows that the substance is succinic anhydride, indicating that succinic anhydride is included in the components removed during the polycondensation stage.

[0127] Figure 4 This is the infrared spectrum of the target product prepared in this example.

[0128] Figure 5 and Figure 6 They are respectively the H NMR spectrum and C NMR spectrum of the target product prepared in this example.

[0129] Figure 7 and Figure 8 They are TGA and DSC test curves of the target product prepared in this example.

[0130] Embodiments 2 to 7

[0131] The synthesis steps are the same as those in Example 1, except that the feed ratio of 3-amino-1,2-propanediol to succinic acid is replaced with 1:2 (Example 2), 1:2.1 (Example 3), 1:2.3 (Example 4), 1:2.4 (Example 5), 1:2.5 (Example 6) and 1:3 (Example 7) in sequence.

[0132] The target product obtained in Example 2 has a number average molecular weight of 13767 Da, a weight average molecular weight of 17453 Da, and a molecular weight distribution of 1.27.

[0133] The target product obtained in Example 3 has a number average molecular weight of 18138 Da, a weight average molecular weight of 25008 Da, and a molecular weight distribution of 1.38.

[0134] The target product obtained in Example 4 has a number average molecular weight of 21799 Da, a weight average molecular weight of 28718 Da, and a molecular weight distribution of 1.32.

[0135] The target product obtained in Example 5 has a number average molecular weight of 21829 Da, a weight average molecular weight of 32102 Da, and a molecular weight distribution of 1.47.

[0136] The target product obtained in Example 6 has a number average molecular weight of 22103 Da, a weight average molecular weight of 32831 Da, and a molecular weight distribution of 1.49.

[0137] The target product obtained in Example 7 has a number average molecular weight of 21089 Da, a weight average molecular weight of 34006 Da, and a molecular weight distribution of 1.61.

[0138] Embodiments 8 to 11

[0139] The synthesis steps are the same as those in Example 1, except that the reaction temperature in the prepolymerization stage is replaced with 140°C (Example 8), 160°C (Example 9), 200°C (Example 10) and 220°C (Example 11) in sequence.

[0140] The target product obtained in Example 8 has a number average molecular weight of 15410 Da, a weight average molecular weight of 19379 Da, and a molecular weight distribution of 1.26.

[0141] The target product obtained in Example 9 has a number average molecular weight of 18162 Da, a weight average molecular weight of 24020 Da, and a molecular weight distribution of 1.32.

[0142] The target product obtained in Example 10 has a number average molecular weight of 19079 Da, a weight average molecular weight of 25610 Da, and a molecular weight distribution of 1.34.

[0143] The target product obtained in Example 11 has a number average molecular weight of 17512 Da, a weight average molecular weight of 22106 Da, and a molecular weight distribution of 1.26.

[0144] Fig. 9 This is a comparison chart of the GPC test curves of the target products prepared in Examples 2, 3, 4, 5, 9 and 11.

[0145] Example 12

[0146] The synthesis steps were the same as those in Example 1, except that the reaction time of the prepolymerization stage was replaced with 3 hours. The target product obtained had a number average molecular weight of 12670 Da, a weight average molecular weight of 17358 Da, and a molecular weight distribution of 1.37. Fig.10 The results of H-NMR spectrum test showed that the product structure contained amide bonds.

[0147] Example 13

[0148] The synthesis steps were the same as those in Example 1, except that the reaction time of the prepolymerization stage was replaced with 24 hours. The target product obtained had a number average molecular weight of 22038 Da, a weight average molecular weight of 30096 Da, and a molecular weight distribution of 1.36.

[0149] Embodiment 14

[0150] The synthesis steps were the same as those in Example 1, except that the reaction time of the polycondensation stage was replaced with 48 hours. The target product obtained had a number average molecular weight of 23048 Da, a weight average molecular weight of 30189 Da, and a molecular weight distribution of 1.31.

[0151] Embodiments 15-16

[0152] The synthesis steps are the same as those of Example 1, except that 10 mg of antimony trioxide (Example 15) and 2 mg of tetrabutyl titanate (Example 16) are added during the polycondensation stage.

[0153] The target product obtained in Example 15 has a number average molecular weight of 31684 Da, a weight average molecular weight of 43152 Da, and a molecular weight distribution of 1.36.

[0154] The target product obtained in Example 16 has a number average molecular weight of 32271 Da, a weight average molecular weight of 50697 Da, and a molecular weight distribution of 1.57.

[0155] Fig.11 This is a comparison chart of the GPC test curves of the target products prepared in Examples 1, 15 and 16.

[0156] Examples 17 to 21

[0157] The synthesis steps are the same as those in Example 1, except that 3-amino-1,2-propanediol is replaced by 2-amino-1,3-propanediol (Example 17), 2-amino-1,3-butanediol (Example 18), 2-amino-1,4-butanediol (Example 19), 2-amino-1,5-pentanediol (Example 20), and 5-amino-1,3-benzenedimethanol (Example 21).

[0158] The target product obtained in Example 17 has a number average molecular weight of 31938 Da, a weight average molecular weight of 58389 Da, and a molecular weight distribution of 1.83. Fig.12 This is the H NMR spectrum of the target product prepared in Example 17.

[0159] The target product obtained in Example 18 has a number average molecular weight of 38630 Da, a weight average molecular weight of 60271 Da, and a molecular weight distribution of 1.56.

[0160] The target product obtained in Example 19 has a number average molecular weight of 41269 Da, a weight average molecular weight of 68370 Da, and a molecular weight distribution of 1.66.

[0161] The target product obtained in Example 20 has a number average molecular weight of 38670 Da, a weight average molecular weight of 61392 Da, and a molecular weight distribution of 1.59.

[0162] The target product obtained in Example 21 has a number average molecular weight of 23271 Da, a weight average molecular weight of 44380 Da, and a molecular weight distribution of 1.91.

[0163] Embodiments 22 to 25

[0164] The synthesis steps are the same as those in Example 1, except that 3-amino-1,2-propanediol is replaced by 2-amino-1,3-propanediol, and succinic acid is replaced by 2-methylsuccinic acid (Example 22), 2-phenylsuccinic acid (Example 23), 2,2-dimethylsuccinic acid (Example 24), and phthalic acid (Example 25) in sequence.

[0165] The target product obtained in Example 22 has a number average molecular weight of 39266 Da, a weight average molecular weight of 67536 Da, and a molecular weight distribution of 1.72. Fig.13 This is the H NMR spectrum of the target product prepared in Example 22.

[0166] The target product obtained in Example 23 has a number average molecular weight of 39683 Da, a weight average molecular weight of 60709 Da, and a molecular weight distribution of 1.53. Fig.14 This is the H NMR spectrum of the target product prepared in Example 23.

[0167] The target product obtained in Example 24 has a number average molecular weight of 41603 Da, a weight average molecular weight of 62369 Da, and a molecular weight distribution of 1.50.

[0168] The target product obtained in Example 25 has a number average molecular weight of 40359 Da, a weight average molecular weight of 61950 Da, and a molecular weight distribution of 1.53.

[0169] Embodiments 26 to 27

[0170] The synthesis steps are the same as those of Example 1, except that 3-amino-1,2-propanediol is replaced by 2-amino-1,3-propanediol, and succinic acid is replaced by succinic anhydride (Example 26) and phthalic anhydride (Example 27) in sequence.

[0171] The target product obtained in Example 26 has a number average molecular weight of 38352 Da, a weight average molecular weight of 63966 Da, and a molecular weight distribution of 1.67.

[0172] The target product obtained in Example 27 has a number average molecular weight of 25401 Da, a weight average molecular weight of 32407 Da, and a molecular weight distribution of 1.28.

[0173] Fig.15 This is the H NMR spectrum of the target product prepared in Example 27.

[0174] Embodiment 28

[0175]

[0176] 3-amino-1,2-propanediol (50 mmol), 1,4-butanediol (50 mmol), and succinic acid (160 mmol) were added to a 150 mL three-necked flask, mechanically stirred, and heated to 180 ° C under nitrogen conditions to carry out esterification and imide cyclization reactions. In the initial stage of the reaction, water vapor can be observed at the outlet. The reaction was carried out for 16 hours to obtain a succinic acid-terminated prepolymer. Turn off the nitrogen, use an oil pump to evacuate the vacuum to less than 100 Pa, gradually heat up to 240 ° C, and the reaction ends after 24 hours. During the reaction, white solids can be observed adhering to the vacuum inlet. The number average molecular weight of the final polycondensation product obtained by gel permeation chromatography (GPC) test is 36670 Da, the weight average molecular weight is 55560 Da, and the molecular weight distribution is 1.52.

[0177] Fig.16 and Fig.17 They are respectively the H NMR spectrum and C NMR spectrum of the target product prepared in this example.

[0178] Embodiment 29

[0179] The synthesis steps are the same as those in Example 27, except that 1,4-butanediol is replaced with an equal molar amount of 1,4-cyclohexanedimethanol, and the target product obtained has a number average molecular weight of 36419 Da, a weight average molecular weight of 48560 Da, and a molecular weight distribution of 1.33.

[0180] Fig.18 This is the H NMR spectrum of the target product prepared in this example.

[0181] Fig.19 This is the carbon NMR spectrum of the target product prepared in this example.

[0182] Embodiment 30

[0183]

[0184] Add 2-amino-1,3-propanediol (40 mmol) and succinic acid (65 mmol) to a 150 mL three-necked flask, stir mechanically, react at 100 ° C for 1 hour, add terephthalic acid (20 mmol), heat to 160 ° C, react under nitrogen for 10 hours, heat to 200 ° C, continue to react under nitrogen for 16 hours, and obtain a prepolymer with a carboxyl terminal group. Turn off the nitrogen, use an oil pump to evacuate the vacuum to less than 100 Pa, and start from 200 ° C and end by heating 10 ° C every 4 hours to 260 ° C. The number average molecular weight of the polymer obtained by gel permeation chromatography (GPC) test is 27080 Da, the weight average molecular weight is 46306 Da, and the molecular weight distribution is 1.71.

[0185] Fig. 20 This is the H NMR spectrum of the target product prepared in this example.

[0186] Examples 31 to 33

[0187] The synthesis steps are the same as those of Example 30, except that terephthalic acid is replaced by 20 mmol of oxalic acid (Example 31), 20 mmol of 1,6-hexanediol (Example 32), and 20 mmol of 1,10-decanedioic acid (Example 33).

[0188] The target product obtained in Example 31 has a number average molecular weight of 25308 Da, a weight average molecular weight of 41506 Da, and a molecular weight distribution of 1.64. Fig.21 This is the H NMR spectrum of the target product prepared in Example 31.

[0189] The target product obtained in Example 32 has a number average molecular weight of 29481 Da, a weight average molecular weight of 47169 Da, and a molecular weight distribution of 1.60. Fig. 22 This is the H NMR spectrum of the target product prepared in Example 32.

[0190] The target product obtained in Example 33 has a number average molecular weight of 32096 Da, a weight average molecular weight of 54242 Da, and a molecular weight distribution of 1.69. Fig.23 This is the H NMR spectrum of the target product prepared in Example 33.

[0191] Embodiment 34

[0192]

[0193] Add 2-amino-1,3-propanediol (40 mmol), hexanediol (20 mmol), succinic acid (90 mmol) to a 150 mL three-necked flask, stir mechanically, react at 100 ° C for 1 hour, add terephthalic acid (20 mmol), heat to 160 ° C, react under nitrogen for 10 hours, heat to 200 ° C, continue to react under nitrogen for 16 hours, and obtain a prepolymer with a carboxyl terminal group. Turn off the nitrogen, use an oil pump to evacuate the vacuum to less than 100 Pa, and start from 200 ° C and end by heating 10 ° C every 4 hours to 260 ° C. The number average molecular weight of the polymer obtained by gel permeation chromatography (GPC) test is 25061 Da, the weight average molecular weight is 46864 Da, and the molecular weight distribution is 1.87.

[0194] Fig.24 This is the H NMR spectrum of the target product prepared in Example 34.

[0195] Embodiment 35

[0196]

[0197] Add 2-amino-1,3-propanediol (20 mmol), 1,4-butanediol (40 mmol), succinic acid (70 mmol) to a 150 mL three-necked flask, stir mechanically, react at 100 ° C for 10 minutes, add 1,6-hexanediol (20 mmol), heat to 160 ° C, react under nitrogen for 10 hours, heat to 200 ° C, continue to react under nitrogen for 16 hours, and obtain a prepolymer with a carboxyl terminal group. Turn off the nitrogen, use an oil pump to evacuate the vacuum to less than 100 Pa, and start from 200 ° C and end by heating 10 ° C every 4 hours to 260 ° C. The number average molecular weight of the polymer obtained by gel permeation chromatography (GPC) test is 31078 Da, the weight average molecular weight is 49414 Da, and the molecular weight distribution is 1.59.

[0198] Fig.25 This is the H NMR spectrum of the target product prepared in Example 35.

Claims

1. A polymer comprising ester-imide structural units of formula (I) and / or (II) and optionally structural units of formula (III) and / or (IV) and / or (V) and / or (VI), in: R1 is a residue of a diol containing an amino group, preferably at least one of a trivalent alkyl group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a trivalent alkyl-aryl-alkyl group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, R2 is a residue of an easily cyclizable dibasic acid, preferably at least one of an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is interrupted by one or more O atoms, an alkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a cycloalkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an arylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a heteroarylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged ring group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, R3 is different from R2 and is the residue of any dibasic acid, for example, it is the residue of the easily cyclized dibasic acid described above for R2; or R2 is the residue of a dibasic acid that is not easily cyclized, and the dibasic acid that is not easily cyclized may be, for example, terephthalic acid or sebacic acid; preferably, R3 is an alkylene group that is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, an alkylene group that is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and is separated by one or more O atoms, an alkenylene group that is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an alkylene group that is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro The invention relates to at least one of a substituted cycloalkylene group, a cycloalkenylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an arylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a heteroarylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or a bridged ring group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, and R4 is at least one of an alkylene group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, an -alkylene-cycloalkylene-alkylene- group which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, a polyether segment or an alkylene group which is interrupted by one or more N atoms.

2. The polymer of claim 1, wherein the trivalent alkyl-aryl-alkyl group in the definition of R1 is a trivalent C1-C 10 Alkyl-C6-C 10 Aryl-C1-C 10 Alkyl, preferably a trivalent C1-C5 alkyl-C6-C8 aryl-C1-C5 alkyl, more preferably a trivalent C1-C3 alkyl-C6-C8 aryl-C1-C3 alkyl, Preferably, R1 is selected from at least one of the following structures: In the above formula, * represents the connection site with the O atom, ** represents the connection site with the N atom; and / or The alkylene group in the definition of R2 is C2-C 10 The alkylene group is preferably a C2-C6 alkylene group, more preferably a C2-C5 alkylene group, and most preferably an ethylene group, 1-methylethylene, 1,1-dimethylethylene, 1,2-dimethylethylene, 1,1,2,2-tetramethylethylene, 1-phenylethylene, 1-benzylethylene, 1,1-diphenylethylene, 1,1-dibenzylethylene, 1,2-diphenylethylene, 1,2-dibenzylethylene, propylene, 1-methylpropylene, 2-methylpropylene, 1,1-dimethylpropylene, 1,2-dimethylpropylene, 2,2-dimethylpropylene, 1,3-dimethylpropylene, 1-phenylpropylene, 2-phenylpropylene, 1,2-diphenylpropylene, 2,2-diphenylpropylene or 1,3-diphenylpropylene; the alkenylene group in the definition of R2 is C2-C6 10 The alkenylene group is preferably a C2-C6 alkenylene group, more preferably a C2-C3 alkenylene group, and most preferably vinylene, 1-methylvinylene, 1,2-dimethylvinylene or propenylene group; the alkylene group in the definition of R2, which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, is interrupted by 1-3 oxygen atoms, such as 2-oxa-1,3-ethylene; the cycloalkylene group in the definition of R2 is a C3-C8 cycloalkylene group, preferably a C4-C6 cycloalkylene group, and most preferably a cyclobutylene or cyclohexylene group; the cycloalkenylene group in the definition of R2 may be a C4-C8 cycloalkenylene group, preferably a C4-C6 cycloalkenylene group, and most preferably a 3-cyclohexene-1,6-diyl group; the arylene group in the definition of R2 is a C6-C 10 Arylene, preferably phenylene, such as 1,6-phenylene; the bridging ring group in the definition of R2 is norbornene; and / or The alkylene group in the definition of R3 is C2-C 10 The alkylene group is preferably a C2-C6 alkylene group, more preferably a C2-C5 alkylene group, and most preferably an ethylene group, 1-methylethylene, 1,1-dimethylethylene, 1,2-dimethylethylene, 1,1,2,2-tetramethylethylene, 1-phenylethylene, 1-benzylethylene, 1,1-diphenylethylene, 1,1-dibenzylethylene, 1,2-diphenylethylene, 1,2-dibenzylethylene, propylene, 1-methylpropylene, 2-methylpropylene, 1,1-dimethylpropylene, 1,2-dimethylpropylene, 2,2-dimethylpropylene, 1,3-dimethylpropylene, 1-phenylpropylene, 2-phenylpropylene, 1,2-diphenylpropylene, 2,2-diphenylpropylene or 1,3-diphenylpropylene; the alkenylene group in the definition of R2 is C2-C6 10 The alkenylene group is preferably a C2-C6 alkenylene group, more preferably a C2-C3 alkenylene group, and most preferably vinylene, 1-methylvinylene, 1,2-dimethylvinylene or propenylene group; the alkylene group in the definition of R2, which is unsubstituted or substituted with a substituent selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, is interrupted by 1-3 oxygen atoms, such as 2-oxa-1,3-ethylene; the cycloalkylene group in the definition of R2 is a C3-C8 cycloalkylene group, preferably a C4-C6 cycloalkylene group, and most preferably a cyclobutylene or cyclohexylene group; the cycloalkenylene group in the definition of R2 may be a C4-C8 cycloalkenylene group, preferably a C4-C6 cycloalkenylene group, and most preferably a 3-cyclohexene-1,6-diyl group; the arylene group in the definition of R2 is a C6-C 10 Arylene, preferably phenylene, such as 1,6-phenylene; the bridging ring group in the definition of R2 is norbornene; and / or The alkylene group in the definition of R4 is C2-C 30 Alkylene, preferably C2-C 25 Alkylene, more preferably C2-C 20 Alkylene, such as ethylene, isopropyl, butylene, pentylene, hexylene, heptylene, octylene, decylene, octadecylene; the cycloalkylene in the definition of R3 is cyclopropylene, cyclobutylene, cyclopentylene or cyclohexylene; the polyether segment in the definition of R3 is a polyethylene glycol segment, a polypropylene glycol segment or a polytetrahydrofuran diol segment, each of which contains 2-1000 repeating structural units, preferably 2-500 repeating structural units, more preferably 2-250 repeating structural units, and most preferably 2-100 repeating structural units; the alkylene in the definition of R3 is separated by one or more N atoms, and the chain is separated by 1-10 N atoms, more preferably 1-5 N atoms, more preferably 1-3 N atoms, and most preferably 1 N atom; preferably, R3 is at least one of the following structural formulas, wherein * is a connection site with other parts of the molecule, x is an integer of 2-20, preferably an integer of 2-18, m is an integer of 2-8, preferably an integer of 2-6, more preferably an integer of 2-4, y is an integer of 2-1000, preferably an integer of 2-500, more preferably an integer of 2-250, and most preferably an integer of 2-100.

3. The polymer according to claim 1 or 2, having a 14 C / 12 C ratio; or the polymer is synthesized using monomers derived from petroleum.

4. A method for preparing a polymer comprising an ester-imide structural unit of formula (I) and / or (II) and optionally a structural unit of formula (III) and / or (IV) and / or (V) and / or (VI), Wherein R1, R2, R3 and R4 are as defined in claim 1 or 2, the method comprising: The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and OH-R1(NH2)-OH, or a mixture of OH-R1(NH2)-OH and OH-R4-OH as a raw material to carry out esterification reaction, amidation reaction and imide cyclization reaction; The second stage: in the absence of a catalyst or in the presence of a catalyst, HOOC-R2-COOH or HOOC-R3-COOH is added to further carry out esterification reaction and imide cyclization reaction to obtain a carboxyl-terminated prepolymer; The third stage: in the absence of catalyst or in the presence of catalyst, remove cyclic anhydride and water to obtain high molecular weight polymer. or, The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and OH-R1(NH2)-OH, or a mixture of OH-R1(NH2)-OH and OH-R4-OH as a raw material to carry out esterification reaction, amidation reaction and imide cyclization reaction; The second stage: adding HOOC-R2-COOH or HOOC-R3-COOH, further carrying out esterification reaction and imide cyclization reaction to obtain a carboxyl-terminated prepolymer, and then adding a catalyst and OH-R4-OH to react to obtain a hydroxyl-terminated prepolymer. The third stage: in the presence of a catalyst, OH-R4-OH and water are removed to obtain a high molecular weight polymer.

5. The method according to claim 4, characterized in that: HOOC-R2-COOH is selected from the group consisting of easily cyclized dibasic acids; preferably selected from the group consisting of alkanedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, alkanedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl, aryl, arylalkyl or alkylaryl and are interrupted by one or more O atoms, alkenedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen or alkyl, cycloalkanedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, cycloalkenedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, aromatic dicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, or The substituent-substituted bridged ring dicarboxylic acid is more preferably selected from at least one of succinic acid, 2-methylsuccinic acid, 2-phenylsuccinic acid, 2-benzylsuccinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylsuccinic acid, 2,3-diphenylsuccinic acid, 1,2-cyclobutanedicarboxylic acid, 2,2,3,3-tetramethylsuccinic acid, methylmaleic acid, dimethylmaleic acid, phthalic acid, hexahydrophthalic acid, norbornene dicarboxylic acid, tetrahydrophthalic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 3-phenylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, diglycolic acid, 2,3-furandicarboxylic acid, 3,4-furandicarboxylic acid, 2,3-pyridinedicarboxylic acid, and 3,4-pyridinedicarboxylic acid.

6. The method according to claim 4 or 5, characterized in that OH-R1(NH2)-OH is selected from an alkanediolamine which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro, or an alkyl-aryl-alkyldiolamine which is unsubstituted or substituted with a substituent selected from halogen, alkyl or nitro; Preferably, it is at least one selected from 3-amino-1,2-propanediol, 2-amino-1,3-propanediol, 2-amino-1,3-butanediol, 2-amino-1,4-butanediol, 2-amino-1,5-pentanediol, 3-amino-1,5-pentanediol, 5-amino-1,3-benzenedimethanol and (2-amino-1,3-phenylene)dimethanol.

7. The method according to any one of claims 4 to 6, characterized in that: HOOC-R3-COOH is any dibasic acid different from HOOC-R2-COOH, for example, it can be selected from the dibasic acid that is easy to cyclize as defined in claim 4, or the dibasic acid that is not easy to cyclize, such as terephthalic acid, 2,5-furandicarboxylic acid, oxalic acid, malonic acid, 1,6-hexanedicarboxylic acid, 1,10-decanedioic acid, 1,18-octadecanedicarboxylic acid; preferably, HOOC-R3-COOH is selected from a substituent that is unsubstituted or selected from halogen, alkyl, aryl, arylalkyl or alkylaryl. Substituted alkanedicarboxylic acids, alkanedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl, aryl, arylalkyl or alkylaryl, interrupted by one or more O atoms, alkenedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen or alkyl, cycloalkanedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, cycloalkenedicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, substituted aromatic dicarboxylic acids, or bridged cyclic dicarboxylic acids which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro; more preferably selected from succinic acid, 2-methylsuccinic acid, 2-phenylsuccinic acid, 2-benzylsuccinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylsuccinic acid, 2,3-diphenylsuccinic acid, oxalic acid, malonic acid, 1,6-hexanedicarboxylic acid, 1,10-decanedioic acid, 1,18-octadecanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, 2,2,3,3-tetramethylsuccinic acid, cis-butanedicarboxylic acid At least one of maleic acid, methylmaleic acid, dimethylmaleic acid, phthalic acid, hexahydrophthalic acid, norbornene diacid, tetrahydrophthalic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 3-phenylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethylglutaric acid, diglycolic acid, 2,3-furandicarboxylic acid, 3,4-furandicarboxylic acid, 2,3-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, terephthalic acid, and 2,5-furandicarboxylic acid.

8. The method according to any one of claims 4 to 7, characterized in that: OH-R4-OH is selected from alkylene glycols which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, OH-alkylene-cycloalkylene-alkylene-OH which are unsubstituted or substituted with substituents selected from halogen, alkyl or nitro, polyether glycols, or alkylene glycols interrupted by one or more N atoms; Preferably, at least one selected from alkylene glycols containing 2 to 18 carbon atoms, polyethylene glycol, polypropylene glycol, polytetrahydrofuran diol, N-methyldiethanolamine, and N-ethyldiethanolamine; More preferably, it is at least one selected from ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,18-octadecanediol, and polyethylene glycol.

9. The method according to any one of claims 4 to 8, characterized in that: The catalyst is selected from at least one of aluminum chloride, ferric chloride, boron trifluoride, stannous chloride, stannous octoate, stannous isooctanoate, dibutyltin dilaurate, monobutyltin oxide, antimony trioxide, zinc oxide, isopropyl titanate, and tetrabutyl titanate.

10. The method according to any one of claims 4 to 9, characterized in that: The molar ratio of (HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH) to (OH-R1(NH2)-OH, or a mixture of OH-R1(NH2)-OH and OH-R4-OH) in the first stage is (1.01-10):1, preferably (1.5-4):1; and / or The reaction temperature of the amidation reaction, esterification reaction and imide cyclization reaction in the first stage and the second stage is 60-300°C, preferably 100-250°C, and the reaction time can be 4-72 hours, preferably 6-24 hours; The reaction temperature in the third stage is 150-300° C., preferably 180-250° C., the reaction time can be 6-72 hours, preferably 6-48 hours, and the vacuum degree is less than 200 Pa, preferably less than 100 Pa.

11. The method according to any one of claims 4 to 10, characterized in that: The first and second stages include the following reaction processes, 12. A method for preparing a polymer comprising an ester-imide structural unit of formula (I) and / or (II) and optionally a structural unit of formula (III) and / or (IV) and / or (V) and / or (VI), Wherein R1, R2, R3 and R4 are as defined above, the method comprises: The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an amide-acid structure represented by formula (VII) as raw materials, and performing an esterification reaction and an imide cyclization reaction to obtain a carboxyl-terminated prepolymer; The second stage: removing cyclic anhydride and water in the absence of catalyst or in the presence of catalyst to obtain a high molecular weight polymer; or The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an amide-acid structure represented by formula (VII) as raw materials, performing an esterification reaction and an imide cyclization reaction to obtain a carboxyl-terminated prepolymer, and then adding a catalyst and reacting with OH-R4-OH to obtain a hydroxyl-terminated prepolymer, The second stage: in the presence of a catalyst, OH-R4-OH and water are removed to obtain a high molecular weight polymer; or The first stage: in the absence of a catalyst or in the presence of a catalyst, using an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an imide structure represented by formula (VIII) as raw materials, and performing an esterification reaction to obtain a carboxyl-terminated prepolymer; The second stage: removing cyclic anhydride and water in the absence of catalyst or in the presence of catalyst to obtain a high molecular weight polymer; or The first stage: in the absence of a catalyst or in the presence of a catalyst, an excess molar ratio of HOOC-R2-COOH or its cyclic anhydride and / or HOOC-R3-COOH and a diol containing an imide structure represented by formula (VIII) are used as raw materials to carry out an esterification reaction to obtain a carboxyl-terminated prepolymer, and then a catalyst is added to react with OH-R4-OH to obtain a hydroxyl-terminated prepolymer. The second stage: in the presence of a catalyst, OH-R4-OH and water are removed to obtain a high molecular weight polymer; wherein R1, R2, R3 and R4 are as defined in claim 1 or 2.

13. A method for preparing a diol containing an amide-acid structure represented by formula (VII), comprising: exist The corresponding OH-R1(NH2)-OH amino diol is reacted with the anhydride of HOOC-R2-COOH in water or an organic solvent in the presence of a catalyst, and then acidified with an acidifying agent, wherein R1 and R2 are as defined in claim 1 or 2, 14. The method of claim 13, wherein the organic solvent is selected from esters such as ethyl acetate and butyl acetate; nitriles such as acetonitrile; amides such as N,N-dimethylformamide and N,N-dimethylacetamide; dimethyl sulfoxide; dioxane; ethers such as trimethyl glycerol and dimethyl sorbitol; and / or The catalyst is selected from potassium carbonate, sodium carbonate, cesium carbonate, sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, disodium hydrogen phosphate, dipotassium hydrogen phosphate, triethylamine, triisopropylamine, trioctylamine, tetramethylguanidine, pyridine, piperidine or 1,8-diazacyclo[5,4,0]undecene-7, 1,5-diazabicyclo[4.3.0]non-5-ene; and / or The acidifying agent is selected from hydrochloric acid, phosphoric acid, boric acid, nitric acid, sulfuric acid, acetic acid, sodium dihydrogen phosphate or potassium dihydrogen phosphate.

15. A method for preparing a diol containing an imide structure represented by formula (VIII), comprising: exist The corresponding OH-R1(NH2)-OH amino diol is reacted with the anhydride of HOOC-R2-COOH in water or an organic solvent in the presence of a catalyst, wherein R1 and R2 are as defined in claim 1 or 2, 16. The method of claim 15, wherein the organic solvent is selected from esters such as ethyl acetate and butyl acetate; nitriles such as acetonitrile; amides such as N,N-dimethylformamide and N,N-dimethylacetamide; dimethyl sulfoxide; dioxane; ethers such as trimethyl glycerol and dimethyl sorbitol; and / or The catalyst is selected from potassium carbonate, sodium carbonate, cesium carbonate, sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, disodium hydrogen phosphate, dipotassium hydrogen phosphate, triethylamine, triisopropylamine, trioctylamine, tetramethylguanidine, pyridine, piperidine, 1,8-diazacyclo[5,4,0]undecene-7 or 1,5-diazabicyclo[4.3.0]non-5-ene.

17. A method for synthesizing a compound represented by formula (VIIII): Including Double bond hydrogenation.

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