An immobilized catalyst and a method for preparing terpolymers of epoxides, cyclic anhydrides and carbon dioxide.

Abstract

The present invention belongs to the field of polymer materials, and specifically relates to a solid-supported catalyst and a method for preparing a terpolymer of alkylene oxide, cyclic anhydride and carbon dioxide. The solid-supported catalyst is a homonuclear bimetallic complex supported by a polymer. A high-pressure reactor is used, a certain amount of solid-supported catalyst is added, and alkylene oxide and cyclic anhydride are added in batches to prepare copolymers at a carbon dioxide pressure of 0.1 to 5.0 MPa and a reaction temperature of 25 to 120° C. The copolymer has the characteristics of aliphatic polyesters, polycarbonates and polyethers, has good biocompatibility and biodegradability, a controllable and adjustable structure, and a polymer molecular weight of 3000 to 100000 g / mol. The polymerization reaction adopted by the present invention is an atom-economic route, with simple post-processing, no waste discharge, and good industrial application prospects.

Description

Technical Field

[0001] The invention belongs to the field of polymer materials, and in particular relates to a solid-supported catalyst and a method for using the solid-supported catalyst to prepare a terpolymer of alkylene oxide, cyclic anhydride and carbon dioxide. Background Art

[0002] The copolymers of alkylene oxide, cyclic anhydride and carbon dioxide have the characteristics of aliphatic polyester, polycarbonate and polyether, realizing the superposition of the advantages of the above three types of polymers in a single substance, and have the good hardness of polycarbonate materials, the good toughness of polyether materials, and the good biocompatibility and biodegradability of aliphatic polyester materials. At the same time, the polymer structure can be controlled and adjusted according to the structure-activity relationship. Without changing the type of raw materials, only the raw material ratio needs to be adjusted to prepare polymers with superior performance and diverse structures. Such copolymers of alkylene oxide, cyclic anhydride and carbon dioxide also have good application prospects. The number average molecular weight of the polymer is 3000-100000 g / mol, the molecular weight distribution is 1.1-1.9, and the good degradation performance makes it have the potential to be used in degradable materials; and the glass transition temperature of the polymer is -50-80℃, and the larger glass transition temperature range also broadens the scope of application of such polymers. Summary of the invention

[0003] The invention belongs to the field of polymer materials, and in particular relates to a solid-supported catalyst and a method for using the solid-supported catalyst to prepare a terpolymer of alkylene oxide, cyclic anhydride and carbon dioxide.

[0004] The technical solution of the present invention:

[0005] A solid-supported catalyst, wherein the solid-supported catalyst is a polymer-supported homonuclear bimetallic complex having the structure:

[0006]

[0007] Where:

[0008] M = Zn or Mg;

[0009] X - Cl -1 Br -1 or I -1 Negative ions;

[0010] n and m are positive integers.

[0011] The synthesis reaction formula of the immobilized catalyst is:

[0012]

[0013] The specific preparation steps of the immobilized catalyst are:

[0014] Under the protection of inert gas, 2-aminocyclohexanol is dissolved in organic solvent 1, sodium hydride is added in a molar ratio of 1 to 1.2:1 to 2-aminocyclohexanol, and the mixture is stirred for 20 to 30 minutes. 2-chloromethylpyridine is added in a molar ratio of 1 to 1 to 2-aminocyclohexanol, and the mixture is heated to reflux for reaction for 20 to 25 hours. Tetrahydrofuran is removed by distillation under reduced pressure, and then purified by column chromatography to obtain intermediate 1.

[0015] Under the protection of inert gas, the intermediate 1 and 3-tert-butyl-2,5-dihydroxybenzaldehyde in a molar ratio of 1:1 are dissolved in an organic solvent 2, heated to reflux, reacted for 8 to 10 hours, and ethanol is removed by vacuum distillation and then purified by column chromatography to obtain the intermediate 2.

[0016] Under the protection of inert gas, the intermediate 2 and norbornene dicarboxylic acid in a molar ratio of 2:1 are dissolved in the organic solvent 1, and N,N'-dicyclohexylcarbodiimide in a molar ratio of 1 to 1.2:1 to the intermediate 2 is added, and the reaction is carried out at room temperature for 68 to 72 hours. The filter cake is collected and purified by column chromatography to obtain the intermediate 3.

[0017] Under the protection of inert gas, intermediate 3 and norbornene in a molar ratio of n:m are dissolved in organic solvent 1, azobisisobutyronitrile in a molar ratio of 1:200-500 to intermediate 3 is added, the temperature is raised to 60-80°C, the reaction is carried out for 6-8h, and the solvent is removed by distillation under reduced pressure to obtain intermediate 4.

[0018] Under the protection of inert gas, the intermediate 4 is dissolved in the organic solvent 1, and (Et)2M in a molar ratio of 2:1 to the intermediate 4 is added at a uniform rate within 2 to 3 hours at room temperature. After the addition, HX in a molar ratio of 1:1 to (Et)2M is added, and the reaction is continued for 2 to 3 hours. The chloroform is removed by distillation under reduced pressure to obtain a supported catalyst.

[0019] The copolymer reaction formula is:

[0020]

[0021] Where:

[0022]

[0023] x, y and z are natural numbers.

[0024] The specific reaction process of the copolymer is as follows: adding a solid-supported catalyst, a small amount of alkylene oxide and an initiator, and selectively adding an organic solvent 3 into a high-pressure reactor, and after the reaction temperature is raised, initiating the reaction under the protection of an inert gas, and injecting carbon dioxide of a specific pressure, and then adding alkylene oxide and cyclic anhydride to the reactor in batches according to a certain proportion, keeping the temperature for a certain period of time, and after observing that the system pressure remains constant, slowly releasing the unreacted carbon dioxide in the reactor, discharging the material, and vacuum drying the product to a constant weight.

[0025] The mass ratio of the added alkylene oxide to the immobilized catalyst after the reaction is initiated is 5000-10000:1.

[0026] The molar ratio of the alkylene oxide to the cyclic anhydride is 2 to 10:1.

[0027] The reaction temperature is 25-120°C, preferably 50-90°C.

[0028] The carbon dioxide pressure is 0.1-5 MPa, preferably 0.8-4 MPa.

[0029] The reaction time is 1 to 12 hours.

[0030] The initiator is one of propylene glycol, butylene glycol, polyethylene glycol 400, polyethylene glycol 600, polypropylene glycol 400 and polypropylene glycol 600.

[0031] The organic solvent 1 is one of dichloromethane, dichloroethane, toluene, 1,4-dioxane, tetrahydrofuran, acetonitrile and chloroform.

[0032] The organic solvent 2 is one of ethanol, methanol, isopropanol and tert-butanol.

[0033] The organic solvent 3 is one of dichloromethane, dichloroethane, toluene, cyclohexane, n-hexane, 1,4-dioxane and tetrahydrofuran.

[0034] The alkylene oxide is one of propylene oxide, ethylene oxide, epichlorohydrin, styrene oxide, phenyl glycidyl ether and cyclohexene oxide.

[0035] The cyclic anhydride is one of succinic anhydride, maleic anhydride, glutaric anhydride, adipic anhydride, phthalic anhydride and 2,3-naphthalene anhydride.

[0036] The number average molecular weight of the copolymer is 3000-100000 g / mol, and the molecular weight distribution is 1.1-1.9.

[0037] Beneficial effects of the present invention:

[0038] (1) The immobilized catalyst used in the present invention has high catalytic efficiency and still has high catalytic activity at a low catalyst concentration.

[0039] (2) The polymerization reaction adopted in the present invention can be carried out at a relatively low pressure and a mild reaction temperature.

[0040] (3) The copolymer obtained in the present invention is obtained by polymerization of alkylene oxide, cyclic acid anhydride and carbon dioxide. The monomers are all commercial bulk chemicals, which have the advantages of cheap and readily available raw materials. DETAILED DESCRIPTION

[0041] The technical solution of the present invention is further described below through examples.

[0042] The terms used in the present invention, unless otherwise specified, generally have the meanings commonly understood by those of ordinary skill in the art.

[0043] In the following examples, various processes and methods not described in detail are conventional methods known in the art. At the same time, due to the large number of catalyst types and the diverse polymer structure ratios, not all preparation methods are described in detail, and typical examples are taken to illustrate the specific process steps of the present invention.

[0044] In the present invention, the alkylene oxide, cyclic anhydride and catalyst numbers used are shown in the following formula.

[0045]

[0046] Example 1

[0047]

[0048] Under nitrogen protection, 2-aminocyclohexanol was dissolved in tetrahydrofuran, sodium hydride (0.19 g, 7.72 mmol) was added in a molar ratio of 1:1 to 2-aminocyclohexanol (0.89 g, 7.72 mmol), and the mixture was stirred for 30 min. 2-chloromethylpyridine (0.98 g, 7.72 mmol) was added in a molar ratio of 1:1 to 2-aminocyclohexanol, and the mixture was heated to reflux for 24 h. Tetrahydrofuran was removed by distillation under reduced pressure, and then purified by column chromatography (the volume ratio of the eluent was dichloromethane: methanol = 5:1) to obtain intermediate 1 (1.27 g, 6.18 mmol, yield 80%). Under nitrogen protection, intermediate 1 (1.35 g, 6.56 mmol) and 3-tert-butyl-2,5-dihydroxybenzaldehyde (1.27 g, 6.56 mmol) in a molar ratio of 1:1 were dissolved in ethanol (30.00 g), heated to reflux, and reacted for 10 h. After ethanol was removed by distillation under reduced pressure, column chromatography (eluent volume ratio of dichloromethane: methanol = 5:1) was performed for purification to obtain intermediate 2 (2.36 g, 6.17 mmol, yield 94%). Under nitrogen protection, intermediate 2 (2.36 g, 6.17 mmol) and norbornene dicarboxylic acid (0.56 g, 3.09 mmol) in a molar ratio of 2:1 were dissolved in dichloromethane, and N,N'-dicyclohexylcarbodiimide (1.53 g, 7.40 mmol) in a molar ratio of 1.2:1 to intermediate 2 was added. The mixture was reacted at room temperature for 72 h, filtered, and the filter cake was collected and purified by column chromatography (the volume ratio of the eluent was dichloromethane: methanol = 2:1) to obtain intermediate 3 (1.71 g, 1.88 mmol, yield 61%). Under nitrogen protection, intermediate 3 (1.71 g, 1.88 mmol) and norbornene (0.27 g, 2.82 mmol) with a molar ratio of n:m (n=2, m=3) were dissolved in toluene (10.0 g), and azobisisobutyronitrile (1.54 mg, 0.0094 mmol) with a molar ratio of 1:200 to intermediate 3 was added, the temperature was raised to 80°C, the reaction was carried out for 8 hours, and the solvent was removed by distillation under reduced pressure to obtain intermediate 4 (1.98 g, 0.94 mmol, yield 100%). Under nitrogen protection, intermediate 4 (1.98 g, 0.94 mmol) was dissolved in chloroform, and (Et)2Zn (1.88 mL, 1.88 mmol, c = 1 M) was added at a constant rate within 2 to 3 h at room temperature in a molar ratio of 2:1 to intermediate 4. After the addition, HI (0.24 g, 1.88 mmol) was added in a molar ratio of 1:1 to (Et)2Zn. The reaction was continued for 2 to 3 h, and the chloroform was removed by distillation under reduced pressure to obtain the immobilized catalyst 1c. 1HNMR(DMSO-d6,400MHz): δ1.05-1.18(m,9H),1.31-1.42(m,45H),1.50-1.66 (m,28H),1.89-1.96(m,4H),2.07-2.12(m,4H),2.81-2.85(m,6H),2.98-3.0 5(m,4H),3.20-3.26(m,8H),3.69(m,4H),4.96(m,8H),5.93-5.98(m,6H),6. 23-6.29(m,4H),7.10-7.63(m,16H),7.91(m,4H),8.25(m,4H),8.38(m,4H).

[0049] Example 1-1

[0050] The experimental steps were the same as those in Example 1, except that HI was replaced by HCl, and n=2, m=3 was replaced by n=3, m=2, to prepare the immobilized catalyst 2c. 1 HNMR(DMSO-d6,400MHz): δ1.05-1.18(m,6H),1.31-1.42(m,60H),1.50-1.66 (m,42H),1.89-1.96(m,6H),2.07-2.12(m,6H),2.81-2.85(m,4H),2.98-3.05 (m,6H),3.20-3.26(m,12H),3.69(m,6H),4.96(m,12H),5.93-5.98(m,4H),6 .23-6.29(m,6H),7.10-7.63(m,24H),7.91(m,6H),8.25(m,6H),8.38(m,6H).

[0051] Example 1-2

[0052] The experimental steps were the same as those in Example 1, except that HI was replaced by HBr, and n=2, m=3 was replaced by n=3, m=3, to prepare the immobilized catalyst 3c. 1HNMR(DMSO-d6,400MHz): δ1.05-1.18(m,9H),1.31-1.42(m,45H),1.50-1.66 (m,28H),1.89-1.96(m,4H),2.07-2.12(m,4H),2.81-2.85(m,6H),2.98-3.0 5(m,4H),3.20-3.26(m,8H),3.69(m,4H),4.96(m,8H),5.93-5.98(m,6H),6. 23-6.29(m,4H),7.10-7.63(m,16H),7.91(m,4H),8.25(m,4H),8.38(m,4H).

[0053] Examples 1-3

[0054] The experimental steps are the same as those in Example 1, except that (Et)2Zn is replaced by (Et)2Mg to prepare the immobilized catalyst 4c. 1 HNMR(DMSO-d6,400MHz): δ1.05-1.18(m,9H),1.31-1.42(m,45H),1.50-1.66 (m,28H),1.89-1.96(m,4H),2.07-2.12(m,4H),2.81-2.85(m,6H),2.98-3.0 5(m,4H),3.20-3.26(m,8H),3.69(m,4H),4.96(m,8H),5.93-5.98(m,6H),6. 23-6.29(m,4H),7.10-7.63(m,16H),7.91(m,4H),8.25(m,4H),8.38(m,4H).

[0055] Examples 1-4

[0056] The experimental steps were the same as those of Example 1-3, except that HI was replaced by HCl, and n=2, m=3 was replaced by n=3, m=2, to prepare the immobilized catalyst 5c. 1HNMR(DMSO-d6,400MHz): δ1.05-1.18(m,6H),1.31-1.42(m,60H),1.50-1.66 (m,42H),1.89-1.96(m,6H),2.07-2.12(m,6H),2.81-2.85(m,4H),2.98-3.05 (m,6H),3.20-3.26(m,12H),3.69(m,6H),4.96(m,12H),5.93-5.98(m,4H),6 .23-6.29(m,6H),7.10-7.63(m,24H),7.91(m,6H),8.25(m,6H),8.38(m,6H).

[0057] Examples 1-5

[0058] The experimental steps are the same as those of Example 1-3, except that HI is replaced by HBr, and n=2, m=3 is replaced by n=3, m=3, to prepare the immobilized catalyst 6c. 1 HNMR(DMSO-d6,400MHz): δ1.05-1.18(m,9H),1.31-1.42(m,45H),1.50-1.66 (m,28H),1.89-1.96(m,4H),2.07-2.12(m,4H),2.81-2.85(m,6H),2.98-3.0 5(m,4H),3.20-3.26(m,8H),3.69(m,4H),4.96(m,8H),5.93-5.98(m,6H),6. 23-6.29(m,4H),7.10-7.63(m,16H),7.91(m,4H),8.25(m,4H),8.38(m,4H).

[0059] Example 2

[0060] A 100mL high-pressure reactor equipped with a magnet was dried at 120°C for more than 12h, evacuated and cooled to room temperature, and then filled with nitrogen for use. Under nitrogen protection, a certain amount of catalyst 1c was weighed at room temperature. A small amount of alkylene oxide 2b and a certain amount of propylene glycol were added, the temperature was raised to 90°C, and the reaction was initiated under nitrogen protection. The molar ratio of alkylene oxide 2b, cyclic anhydride 1a and 1c added after the reaction was initiated was 10000 / 1000 / 1, 3MPa of carbon dioxide was filled, alkylene oxide 2b and cyclic anhydride 1a were added in batches, the reaction was continued for 3h, stirring was stopped, and the unreacted carbon dioxide in the reactor was slowly discharged to obtain a colorless and transparent polymer with a polymerization molecular weight of 36000g / mol and a molecular weight distribution of 1.7.

[0061] Example 3

[0062] A 100mL high-pressure reactor equipped with a magnetic device was dried at 120°C for more than 12h, evacuated and cooled to room temperature, and then charged with nitrogen for use. Under nitrogen protection, a certain amount of catalyst 2c was weighed at room temperature, and then a small amount of alkylene oxide 1b and a certain amount of butanediol were added, and toluene was added. The temperature was raised to 75°C, and the reaction was initiated under nitrogen protection. The molar ratio of alkylene oxide 1b, cyclic anhydride 2a and 2c added after the reaction was initiated was 5000 / 1000 / 1, and 3MPa of carbon dioxide was charged. Alkylene oxide 1b and cyclic anhydride 2a were added in batches, and the reaction was continued for 2h. Stirring was stopped, and the polymerization molecular weight was 34000g / mol, and the molecular weight distribution was 1.6.

[0063] Example 4

[0064] A 100mL high-pressure reactor equipped with a magnet was dried at 120°C for more than 12h, evacuated and cooled to room temperature, and then filled with nitrogen for use. Under nitrogen protection, a certain amount of catalyst 3c was weighed at room temperature, and a small amount of alkylene oxide 6b and a certain amount of polyethylene glycol 400 were added, and the temperature was raised to 75°C. The reaction was initiated under nitrogen protection. The molar ratio of alkylene oxide 6b, cyclic anhydride 3a and 3c added after the reaction was initiated was 6000 / 1000 / 1, and 3MPa of carbon dioxide was filled. Alkylene oxide 6b and cyclic anhydride 3a were added in batches, and the reaction was continued for 3h. Stirring was stopped, and the unreacted carbon dioxide in the reactor was slowly discharged to obtain a colorless and transparent polymer with a polymerization molecular weight of 61000g / mol and a molecular weight distribution of 1.4.

[0065] Example 5

[0066] A 100mL high-pressure reactor equipped with a magnet was dried at 120°C for more than 12h, evacuated and cooled to room temperature, and then filled with nitrogen for use. Under nitrogen protection, a certain amount of catalyst 4c was weighed at room temperature, and a small amount of alkylene oxide 5b and a certain amount of polyethylene glycol 600 were added, and the temperature was raised to 90°C. The reaction was initiated under nitrogen protection. The molar ratio of alkylene oxide 5b, cyclic anhydride 4a and 4c added after the reaction was initiated was 5000 / 500 / 1, 3MPa of carbon dioxide was filled, and alkylene oxide 5b and cyclic anhydride 4a were added in batches. The reaction was continued for 6h, and stirring was stopped. The unreacted carbon dioxide in the reactor was slowly discharged to obtain a colorless and transparent polymer with a polymerization molecular weight of 3300g / mol and a molecular weight distribution of 1.1.

[0067] Example 6

[0068] A 100mL high-pressure reactor equipped with a magnet was dried at 120°C for more than 12h, evacuated and cooled to room temperature, and then filled with nitrogen for use. Under nitrogen protection, a certain amount of catalyst 5c was weighed at room temperature, and a small amount of alkylene oxide 3b and a certain amount of polypropylene glycol 400 were added, and the temperature was raised to 90°C. The reaction was initiated under nitrogen protection. The molar ratio of alkylene oxide 3b, cyclic anhydride 5a and 5c added after the reaction was initiated was 10000 / 2000 / 1, and 5MPa of carbon dioxide was filled. Alkylene oxide 3b and cyclic anhydride 5a were added in batches, and the reaction was continued for 10h. Stirring was stopped, and the unreacted carbon dioxide in the reactor was slowly discharged to obtain a colorless and transparent polymer with a polymerization molecular weight of 48000g / mol and a molecular weight distribution of 1.7.

[0069] Example 7

[0070] A 100mL high-pressure reactor equipped with a magnet was dried at 120°C for more than 12h, evacuated and cooled to room temperature, and then charged with nitrogen for use. Under nitrogen protection, a certain amount of catalyst 6c was weighed at room temperature, and then a small amount of alkylene oxide 4b and a certain amount of polypropylene glycol 600 were added, 1,4-dioxane was added, the temperature was raised to 90°C, and the reaction was initiated under nitrogen protection. The molar ratio of alkylene oxide 4b, cyclic anhydride 6a and 6c added after the reaction was initiated was 5000 / 2000 / 1, 3MPa of carbon dioxide was charged, alkylene oxide 4b and cyclic anhydride 6a were added in batches, the reaction was continued for 12h, stirring was stopped, and the unreacted carbon dioxide in the reactor was slowly discharged to obtain a colorless and transparent polymer with a polymerization molecular weight of 46000g / mol and a molecular weight distribution of 1.8.

Claims

1. A supported catalyst, characterized in that: The immobilized catalyst is a polymer-supported homonuclear bimetallic complex with the structure: Where: M = Zn or Mg; X - Cl -1 Br -1 or I -1 Negative ions; n and m are positive integers.

2. The method for preparing a supported catalyst according to claim 1, characterized in that: The synthetic reaction formula is: The specific preparation steps of the immobilized catalyst are: Under the protection of inert gas, 2-aminocyclohexanol is dissolved in organic solvent 1, sodium hydride is added in a molar ratio of 1 to 1.2:1 to 2-aminocyclohexanol, and the mixture is stirred for 20 to 30 minutes. 2-chloromethylpyridine is added in a molar ratio of 1 to 1 to 2-aminocyclohexanol, and the mixture is heated to reflux for reaction for 20 to 25 hours. Tetrahydrofuran is removed by distillation under reduced pressure, and then purified by column chromatography to obtain intermediate 1; Under the protection of inert gas, the intermediate 1 and 3-tert-butyl-2,5-dihydroxybenzaldehyde in a molar ratio of 1:1 are dissolved in an organic solvent 2, heated to reflux, reacted for 8 to 10 hours, ethanol is removed by vacuum distillation, and then purified by column chromatography to obtain the intermediate 2; Under the protection of inert gas, the intermediate 2 and norbornene dicarboxylic acid in a molar ratio of 2:1 are dissolved in an organic solvent 1, and N,N'-dicyclohexylcarbodiimide in a molar ratio of 1 to 1.2:1 to the intermediate 2 is added, reacted at room temperature for 68 to 72 hours, filtered, the filter cake is collected, and purified by column chromatography to obtain the intermediate 3; Under the protection of inert gas, the intermediate 3 and norbornene in a molar ratio of n:m are dissolved in an organic solvent 1, azobisisobutyronitrile in a molar ratio of 1:200-500 to the intermediate 3 is added, the temperature is raised to 60-80°C, the reaction is carried out for 6-8h, and the solvent is removed by distillation under reduced pressure to obtain the intermediate 4; Under the protection of inert gas, the intermediate 4 was dissolved in the organic solvent 1, and (Et)2M in a molar ratio of 2:1 to the intermediate 4 was added at a uniform rate within 2 to 3 hours at room temperature. After the addition, HX in a molar ratio of 1:1 to (Et)2M was added, and the reaction was continued for 2 to 3 hours. The chloroform was removed by distillation under reduced pressure to obtain the immobilized catalyst.

3. A method for preparing a terpolymer of alkylene oxide, cyclic anhydride and carbon dioxide using the immobilized catalyst according to claim 1 or the immobilized catalyst prepared according to claim 2, characterized in that: The copolymer reaction formula is: Where: x, y and z are natural numbers; The specific reaction process of the copolymer is as follows: adding a solid-supported catalyst, a small amount of alkylene oxide and an initiator, and selectively adding an organic solvent 3 into a high-pressure reactor, and after the reaction temperature is raised, initiating the reaction under the protection of an inert gas, and charging with carbon dioxide of a specific pressure, and then adding alkylene oxide and cyclic anhydride to the reactor in batches according to a certain proportion, and keeping the temperature for a certain period of time, after observing that the system pressure remains constant, slowly releasing the unreacted carbon dioxide in the reactor, discharging the material, and vacuum drying the product to a constant weight; The mass ratio of the alkylene oxide added after the reaction is initiated to the immobilized catalyst is 5000-10000:1; the molar ratio of the alkylene oxide to the cyclic anhydride is 2-10:1; The reaction temperature is 25-120° C.; the carbon dioxide pressure is 0.1-5 MPa; and the reaction time is 1-12 hours.

4. The method according to claim 3, characterized in that The initiator is one of propylene glycol, butylene glycol, polyethylene glycol 400, polyethylene glycol 600, polypropylene glycol 400 and polypropylene glycol 600.

5. The method according to claim 3, characterized in that: The organic solvent 1 is one of dichloromethane, dichloroethane, toluene, 1,4-dioxane, tetrahydrofuran, acetonitrile and chloroform; the organic solvent 2 is one of ethanol, methanol, isopropanol and tert-butanol; the organic solvent 3 is one of dichloromethane, dichloroethane, toluene, cyclohexane, n-hexane, 1,4-dioxane and tetrahydrofuran.

6. The method according to claim 3, characterized in that The alkylene oxide is one of propylene oxide, ethylene oxide, epichlorohydrin, styrene oxide, phenyl glycidyl ether and cyclohexene oxide.

7. The method according to claim 3, characterized in that The cyclic anhydride is one of succinic anhydride, maleic anhydride, glutaric anhydride, adipic anhydride, phthalic anhydride and 2,3-naphthalene anhydride.

8. The method according to claim 3, characterized in that The number average molecular weight of the copolymer is 3000-100000 g / mol, and the molecular weight distribution is 1.1-1.9.

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