Polyether polyol of high molecular weight sucrose and synthesis method thereof

Abstract

The invention belongs to the technical field of chemical engineering and medicines, and particularly relates to polyether polyol of high-molecular-weight sucrose and a synthesis method of the polyether polyol. The average molecular weight of the sucrose polyether polyol is 5000-10000, adding an initiator, namely a mixture consisting of sucrose, small molecular alcohol and water, and an alkali metal catalyst into a reactor, heating, and introducing epoxide to carry out polymerization reaction; preserving heat, curing, heating and dehydrating; introducing epoxide for polymerization reaction, and adding water and an adsorbent for refining to obtain a refined polyether polyol stub bar; the preparation method comprises the following steps: adding a refined polyether polyol material head, DMC and an acidic material into a container, heating for dehydration, introducing epoxide for polymerization reaction, and adding water and an adsorbent for refining to obtain the polyether polyol of high molecular weight cane sugar. The sucrose polyether with the ultra-high molecular weight can be synthesized, is narrow in molecular weight distribution, high in functionality and stable in storage, and is applied to the fields of semi-rigid foam polyurethane, polyurethane elastomers and the like, or applied to micromolecule inclusion, recognition and slow release in the fields of medicines and foods.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical industry and medicine, and particularly relates to a polyether polyol of high molecular weight sucrose and a synthesis method thereof. Background Art

[0002] Sucrose molecules have a hollow cylindrical three-dimensional ring structure. They begin to decompose when heated to about 200°C and have good thermal stability. They are hygroscopic, but they easily form various stable hydrates. Many functional groups can be cross-linked on sucrose molecules or sucrose can be cross-linked on polymers for chemical modification or polymerization with sucrose as a monomer. The inside of the ring is relatively hydrophobic, while all hydroxyl groups are on the outside of the molecule. However, sucrose has the disadvantages of being solid at room temperature and having a high melting point, so it cannot be normally used in the field of polyurethane. This requires modification. The modified sucrose is prepared by introducing epoxides to prepare sucrose polyether polyols, which can turn its room temperature solid into liquid. Sucrose polyether polyols have high functionality, easy to control synthesis process conditions, and high product reactivity and good stability. They are stable in storage and can be used in fields such as semi-rigid foam polyurethanes and polyurethane elastomers. Sucrose polyether polyols are mostly used in the synthesis of rigid foam polyethers in the form of low molecular weight materials.

[0003] Polyether polyols have certain application potential in the medical field, such as the preparation of drug carriers and biomedical materials. Drug carriers refer to the inclusion of drugs in appropriate materials so that the drugs can better reach the target tissue or organ, thereby improving the therapeutic effect of the drugs. When polyether polyols are used to prepare nano drug carriers, they have the advantages of stability, good biocompatibility, and controllable drug release rate.

[0004] However, high molecular weight and molecular weight distribution are crucial for the performance of drug carriers. If the molecular weight of polyether polyols is low or the molecular weight distribution is wide, it may affect their stability as drug carriers and the controllability of drug release, thereby limiting their application in the pharmaceutical field. Especially in application scenarios that require small molecule inclusion, recognition and sustained release, polyether polyols with high molecular weight and narrow molecular weight distribution are more advantageous.

[0005] In the prior art, it is difficult to synthesize high molecular weight products from sucrose polyether polyols, and their molecular weight distribution is relatively wide, which directly affects their application range, such as in the fields of medicine and food for small molecule inclusion, recognition, and sustained release. Summary of the invention

[0006] The invention provides a high molecular weight sucrose polyether polyol, which has a high molecular weight and a narrow molecular weight distribution, to solve the problem that sucrose polyether polyol is difficult to synthesize a high molecular weight product and has a wide molecular weight distribution.

[0007] The invention also provides a synthesis method thereof, which is scientific, reasonable and suitable for large-scale production.

[0008] In order to solve the above problems, the technical solution of the present invention is:

[0009] The synthesis method of the high molecular weight sucrose polyether polyol of the present invention has an average molecular weight of sucrose polyether polyol of 5000-10000, and its raw materials include initiator: sucrose, small molecule alcohol, water, epoxide and adsorbent;

[0010] Prepared by the following steps:

[0011] 1) In a high-pressure reactor equipped with temperature control, stirring and condensing devices, an initiator: a mixture of sucrose, a small molecule alcohol and water, an alkali metal catalyst, inert gas replacement, after the oxygen content is less than 100 ppm, vacuuming to -0.098 MPa under negative pressure, heating, and introducing epoxide for the first time to carry out anionic polymerization reaction; then heat preservation and aging until the reaction is complete, heating and dehydration; inert gas replacement, when the oxygen content in the kettle is measured to be less than 100 ppm, vacuuming to -0.098 MPa, introducing epoxide again to carry out polymerization reaction, and after the reaction is complete, a polyether polyol with a specific viscosity (500-2000 mPa·s at 25° C.) is obtained, and water and an adsorbent are added for purification to obtain a refined polyether polyol head;

[0012] 2) In a high-pressure reaction vessel equipped with temperature control, stirring and condensing devices, add refined polyether polyol head, DMC and acidic substances, replace with inert gas, and when the oxygen content in the kettle is measured to be less than 100ppm, evacuate to -0.098MPa, heat and dehydrate, and then introduce epoxide for polymerization reaction. After the reaction is complete, add water and adsorbent for purification to obtain high molecular weight sucrose polyether polyol.

[0013] The adsorbent is aluminum silicate or magnesium silicate or magnesium aluminum silicate; the epoxide includes one or more of ethylene oxide, propylene oxide and butylene oxide.

[0014] The sucrose is one or more of imported sucrose and domestic sucrose.

[0015] The small molecule alcohol in step 1) is a conventional alcohol compound, including one or more of diethylene glycol, propylene glycol, dipropylene glycol or glycerol; the water is deionized water.

[0016] The amount of water in the initiator described in step 1) is 1% to 10% of the total mass of the raw materials in step 1), the amount of sucrose in the initiator is 5% to 30% of the total mass of the raw materials in step 1), and the amount of small molecular alcohol in the initiator is 1% to 10% of the total mass of the raw materials in step 1).

[0017] The amount of the epoxide introduced for the first time in step 1) is 1 to 3 times the total mass of the initiator; the amount of the epoxide introduced again in step 1) is 2 to 6 times the total mass of the initiator.

[0018] The heating in step 1) is to 80-150°C, the polymerization reaction temperature is 80-150°C, and the pressure is 0-0.6MPa; the heating dehydration temperature in step 1) is 90-110°C, and the moisture content is controlled at 0-0.2wt.% of the total mass.

[0019] After the reaction described in step 1) is completed, the amount of water and adsorbent added is 2-10% and 0.1-1% of the total mass of the raw materials in step 1) respectively; after the reaction described in step 2) is completed, the amount of water and adsorbent added is 2-10% and 0.1-1% of the total mass of the raw materials in step 2) respectively.

[0020] The temperature of the heating dehydration in step 2) is 80-150°C and the pressure is 0-0.09MPa; the reaction temperature of the polymerization reaction in step 2) is 130-150°C and the pressure is 0-0.6MPa.

[0021] The amount of the epoxide introduced in step 2) is 10% to 95% of the total mass of the raw materials in step 2).

[0022] The beneficial effects of the present invention are as follows:

[0023] (1) The present invention uses three initiators, namely sucrose, water, and small molecule alcohol, which can efficiently initiate and carry out subsequent reactions compared to traditional double initiators.

[0024] (2) In the step 1) of the present invention, the alkali metal catalytic process is used to purify the polyether polyol raw material, while the bimetallic (DMC) catalytic process is used to synthesize the finished high molecular weight sucrose polyether polyol. It is difficult for traditional sucrose to be directly catalyzed by DMC, while KOH can well catalyze multi-initiator polyether. DMC is a coordination polymerization catalyst. During the polymerization process, DMC provides active sites. Each catalytic active center is connected to the chains of many initiators. The epoxy compound as the polymerization monomer is inserted into the vacant site provided by the active center for ring-opening polymerization to achieve the chain growth of the polymer. Then, a substitution reaction occurs between the initiator and the active structure formed by the epoxy compound and the catalyst, and the rate of the substitution reaction is higher than the growth rate of the active chain. Since the complexation rate of the activated catalyst with the hydroxyl compound is much higher than the chain growth rate and the isomerization rate of the monomer, the defect of completing the polymer chain growth by proton transfer in the anionic polymerization process is eliminated, the probability of isomerization of po in the polymerization process is reduced, the conversion rate of the epoxy compound is increased, and the content of the monohydroxyl polyether is reduced, so that the final product has a narrower relative molecular weight distribution. Therefore, after using KOH to synthesize a polyether with a certain molecular weight from initiators such as sucrose, the polyether is catalyzed by DMC to obtain a sucrose polyether with a higher molecular weight.

[0025] (3) The present invention designs the molecular weight of the polyether polyol feedstock and controls it by characterizing it through viscosity. The molecular weight of the feedstock is the key to the subsequent synthesis of high molecular weight sucrose polyether polyol. Within this viscosity range, it can be better initiated by DMC in step 2).

[0026] (4) Sucrose polyether is mostly used in the synthesis of rigid foam polyether in the form of low molecular weight materials. The present invention can synthesize ultra-high molecular weight sucrose polyether, which has a narrow molecular weight distribution, high functionality, easy control of synthesis process conditions, high product reactivity and good stability. It is stable in storage and can be used in the fields of semi-rigid foam polyurethane and polyurethane elastomer, or in the fields of medicine and food for small molecule inclusion, identification and sustained release. DETAILED DESCRIPTION

[0027] The present invention will be further described below with reference to the embodiments.

[0028] Unless otherwise specified, all raw materials used in the examples are commercially available.

[0029] The magnesium aluminum silicate is ZH-AD100NS, which is commonly available in the market.

[0030] The aluminum silicate is ZH-AD500NS, which is commonly available in the market.

[0031] Example 1

[0032] 1) Add 137g sucrose, 42.4g diethylene glycol, 27.2g water and 3.8g potassium hydroxide to a 2-liter stainless steel kettle for nitrogen replacement. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 90℃, add propylene oxide, keep the temperature in the kettle at 100℃ and the pressure at 0.1MPa, and continuously add 400g propylene oxide. After the propylene oxide feeding is completed, the internal pressure is ripened for 3 hours; vacuum remove the unreacted propylene oxide, continue to evacuate and dehydrate (the temperature of heating and dehydration is 105℃), and the moisture content of the material in the kettle is 0.18%. Evacuate to -0.098MPa, replace with nitrogen, and when the oxygen content in the kettle is less than 100ppm, heat to 90℃, start adding propylene oxide, keep the temperature in the kettle at 110℃ and the pressure at 0.1MPa, and continuously add 856g propylene oxide. After the propylene oxide feeding was completed, the reaction was carried out under internal pressure for 3 hours. Unreacted propylene oxide was removed by vacuum, 45 g of water and 3.2 g of magnesium aluminum silicate were added, the temperature was raised for dehydration, and the mixture was filtered to obtain a refined polyether polyol feedstock 1.

[0033] 2) Add 243g of feed 1, 0.05g of DMC, and 0.06g of 98% sulfuric acid to a 2-liter stainless steel kettle, and replace with nitrogen. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 110°C, and dehydrate with nitrogen for 1 hour. After the vacuum is turned off, continue to heat to 130°C, start adding propylene oxide, keep the temperature in the kettle at 135°C, and the pressure at 0.1MPa, and continuously add 1300g of propylene oxide. After the propylene oxide feeding is completed, the internal pressure is ripened for 1 hour. Remove the unreacted propylene oxide by vacuum, add 45g of water and 3.2g of magnesium aluminum silicate, heat up for dehydration, and filter to obtain the refined polyether polyol product a.

[0034] Example 2

[0035] 1) Add 137g sucrose, 42.4g diethylene glycol, 27.2g water, and 3.8g potassium hydroxide to a 2-liter stainless steel kettle for nitrogen replacement. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 90°C, add epoxide, maintain the temperature in the kettle at 100°C and the pressure at 0.1MPa, and continuously add 200g propylene oxide and 200g ethylene oxide. After the epoxide feeding is completed, the internal pressure is ripened for 3 hours; vacuum remove the unreacted epoxide, continue vacuum dehydration (the temperature of heating and dehydration is 105°C), and the moisture content of the material in the kettle is measured to be 0.18%. The mixture was evacuated to -0.098 MPa and replaced with nitrogen. After the oxygen content in the kettle was measured to be less than 100 ppm, the temperature was raised to 90°C and epoxide was added. The temperature in the kettle was kept at 110°C and the pressure was 0.1 MPa. 428 g of propylene oxide and 428 g of ethylene oxide were added continuously. After the propylene oxide feeding was completed, the reaction was carried out under internal pressure for 3 hours. Unreacted propylene oxide was removed by vacuum, 45 g of water and 3.2 g of magnesium aluminum silicate were added, the temperature was raised for dehydration, and the mixture was filtered to obtain the refined polyether polyol material head 2.

[0036] 2) Add 243g of feed 2, 0.05g of DMC, and 0.06g of 98% sulfuric acid to a 2-liter stainless steel kettle, and replace with nitrogen. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 110°C, and dehydrate with nitrogen for 1 hour. After the vacuum is turned off, continue to heat to 130°C, start adding propylene oxide, keep the temperature in the kettle at 135°C, and the pressure at 0.1MPa, and continuously add 1300g of propylene oxide. After the propylene oxide feeding is completed, the internal pressure is ripened for 1 hour. Vacuum off the unreacted propylene oxide, add 45g of water and 3.2g of magnesium aluminum silicate, heat up for dehydration, and filter to obtain the refined polyether polyol product b.

[0037] Example 3

[0038] 1) Add 137g sucrose, 42.4g diethylene glycol, 27.2g water and 3.8g potassium hydroxide to a 2-liter stainless steel kettle for nitrogen replacement. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 90℃, add propylene oxide, keep the temperature in the kettle at 100℃ and the pressure at 0.1MPa, and continuously add 400g propylene oxide. After the propylene oxide feeding is completed, the internal pressure is ripened for 3 hours; vacuum remove the unreacted propylene oxide, continue to evacuate and dehydrate (the temperature of heating and dehydration is 105℃), and the moisture content of the material in the kettle is 0.18%. Evacuate to -0.098MPa, replace with nitrogen, and when the oxygen content in the kettle is less than 100ppm, heat to 90℃, start adding propylene oxide, keep the temperature in the kettle at 110℃ and the pressure at 0.1MPa, and continuously add 856g propylene oxide. After the propylene oxide feeding was completed, the reaction was carried out under internal pressure for 3 hours. Unreacted propylene oxide was removed by vacuum, 45 g of water and 3.2 g of magnesium aluminum silicate were added, the temperature was raised for dehydration, and the mixture was filtered to obtain a refined polyether polyol feedstock 1.

[0039] 2) Add 243g of material head a, 0.05g of DMC, and 0.06g of 98% sulfuric acid to a 2-liter stainless steel kettle, and replace with nitrogen. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 110°C, and dehydrate with nitrogen for 1 hour. After the vacuum is turned off, continue to heat to 130°C, start adding epoxide, maintain the temperature in the kettle at 135°C, and the pressure at 0.1MPa, and continuously add 650g of propylene oxide and 650g of ethylene oxide. After the epoxide feeding is completed, the internal pressure is ripened for 1 hour. Remove the unreacted epoxide by vacuum, add 45g of water and 3.2g of magnesium aluminum silicate, heat to dehydrate, and filter to obtain the refined polyether polyol product c.

[0040] Example 4

[0041] 1) Add 137g sucrose, 42.4g diethylene glycol, 27.2g water, and 3.8g potassium hydroxide to a 2-liter stainless steel kettle for nitrogen replacement. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 90°C, add epoxide, maintain the temperature in the kettle at 100°C and the pressure at 0.1MPa, and continuously add 200g propylene oxide and 200g ethylene oxide. After the epoxide feeding is completed, the internal pressure is ripened for 3 hours; vacuum remove the unreacted epoxide, continue to vacuum dehydrate (the temperature of heating and dehydration is 105°C), and the moisture content of the material in the kettle is measured to be 0.18%. The mixture was evacuated to -0.098 MPa and replaced with nitrogen. After the oxygen content in the kettle was measured to be less than 100 ppm, the temperature was raised to 90°C and epoxide was added. The temperature in the kettle was kept at 110°C and the pressure was 0.1 MPa. 428 g of propylene oxide and 428 g of ethylene oxide were added continuously. After the propylene oxide feeding was completed, the reaction was carried out under internal pressure for 3 hours. Unreacted propylene oxide was removed by vacuum, 45 g of water and 3.2 g of magnesium aluminum silicate were added, the temperature was raised for dehydration, and the mixture was filtered to obtain the refined polyether polyol material head 2.

[0042] 4) Add 243 head b, 0.05g DMC, and 0.06g 98% sulfuric acid to a 2-liter stainless steel kettle for nitrogen replacement. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 110°C, and perform nitrogen dehydration for 1 hour. After the vacuum is closed, continue to heat to 130°C, start adding epoxide, maintain the temperature in the kettle at 135°C, and the pressure at 0.1MPa, and continuously add 650g propylene oxide and 650g ethylene oxide. After the epoxide feeding is completed, the internal pressure is ripened for 1 hour. Remove the unreacted epoxide by vacuum, add 45g water and 3.2g magnesium aluminum silicate, heat to dehydrate, and filter to obtain the refined polyether polyol product d.

[0043] Comparative Example 1

[0044] 1) Add 137g sucrose, 45.4g diethylene glycol, and 3.8g potassium hydroxide to a 2-liter stainless steel kettle for nitrogen replacement. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 90℃, add propylene oxide, keep the temperature in the kettle at 100℃, and the pressure at 0.1MPa, and continuously add 400g propylene oxide. After the propylene oxide feeding is completed, the internal pressure is ripened for 8 hours; vacuum remove the unreacted propylene oxide, continue to evacuate and dehydrate (the temperature of heating and dehydration is 105℃), and the moisture content of the material in the kettle is 0.18%. Evacuate to -0.098MPa, replace with nitrogen, and when the oxygen content in the kettle is less than 100ppm, heat to 90℃, start adding propylene oxide, keep the temperature in the kettle at 110℃, and the pressure at 0.1MPa, and continuously add 856g propylene oxide. After the propylene oxide feeding is completed, the reaction is carried out under internal pressure for 8 hours. The unreacted propylene oxide is removed by vacuum, 45 g of water and 3.2 g of magnesium aluminum silicate are added, the temperature is raised for dehydration, and filtration is performed to obtain the refined polyether polyol raw material ①.

[0045] Comparative Example 2

[0046] 1) Add 137g sucrose, 42.4g diethylene glycol, 27.2g water and 3.8g potassium hydroxide to a 2-liter stainless steel kettle for nitrogen replacement. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 90℃, add propylene oxide, keep the temperature in the kettle at 100℃ and the pressure at 0.1MPa, and continuously add 400g propylene oxide. After the propylene oxide feeding is completed, the internal pressure is ripened for 3 hours; vacuum remove the unreacted propylene oxide, continue to evacuate and dehydrate (the temperature of heating and dehydration is 105℃), and the moisture content of the material in the kettle is 0.18%. Evacuate to -0.098MPa, replace with nitrogen, and when the oxygen content in the kettle is less than 100ppm, heat to 90℃, start adding propylene oxide, keep the temperature in the kettle at 110℃ and the pressure at 0.1MPa, and continuously add 856g propylene oxide. After the propylene oxide feeding was completed, the reaction was carried out under internal pressure for 3 hours. Unreacted propylene oxide was removed by vacuum, 45 g of water and 3.2 g of magnesium aluminum silicate were added, the temperature was raised for dehydration, and the mixture was filtered to obtain a refined polyether polyol feedstock 1.

[0047] 2) Add 243g of feed 1 and 4.8g of KOH to a 2-liter stainless steel kettle, and replace with nitrogen. When the oxygen content in the kettle is less than 100ppm, evacuate to -0.098MPa, heat to 110°C, and dehydrate with nitrogen for 1 hour. After the vacuum is turned off, add propylene oxide, keep the temperature in the kettle at 110°C and the pressure at 0.1MPa, and continuously add 1300g of propylene oxide. After the propylene oxide feeding is completed, the internal pressure is ripened for 10 hours. Remove the unreacted propylene oxide by vacuum, add 45g of water and 3.2g of magnesium aluminum silicate, heat up for dehydration, and filter to obtain the refined polyether polyol product A.

[0048] The test results of double initiators and triple initiators are shown in Table 1:

[0049] Table 1 Test results of material head 1 and material head ①

[0050]

[0051] The test results of KOH and DMC synthetic products are shown in Table 2:

[0052] Table 2 Test results of products a and A

[0053]

[0054] The test results of products a, b, c, d are shown in Table 3:

[0055] Table 3 Test results of products a, b, c, d

[0056]

[0057] The above data show that a sucrose-based polyether polyol can be synthesized according to the method of the present invention. The sucrose polyether polyol has high functionality, easy to control synthesis process conditions, high product reactivity and good stability. It is stable in storage and can be used in the fields of semi-rigid foam polyurethane and polyurethane elastomer, or in the fields of medicine and food for small molecule inclusion, recognition and sustained release.

[0058] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for synthesizing a polyether polyol of high molecular weight sucrose, characterized in that: The average molecular weight of sucrose polyether polyol is 5000-10000, and its raw materials include initiator: sucrose, small molecule alcohol, water, epoxide and adsorbent; Prepared by the following steps: 1) In a high-pressure reactor, an initiator, a mixture of sucrose, a small molecule alcohol and water, and an alkali metal catalyst are added, the temperature is raised, and epoxide is introduced for the first time to carry out anionic polymerization reaction; then the temperature is kept and aged until the reaction is complete, and the temperature is raised for dehydration; the epoxide is introduced again for polymerization reaction, and after the reaction is complete, a polyether polyol with a viscosity of 500-2000 mPa·s is obtained, and water and an adsorbent are added for purification to obtain a refined polyether polyol head; 2) In a high-pressure reaction vessel, add refined polyether polyol raw material, DMC, and acidic substances, heat and dehydrate, then introduce epoxide to carry out polymerization reaction, and after the reaction is complete, add water and adsorbent for purification to obtain high molecular weight sucrose polyether polyol.

2. The method for synthesizing the polyether polyol of high molecular weight sucrose according to claim 1, characterized in that: The adsorbent is aluminum silicate or magnesium silicate or magnesium aluminum silicate; the epoxide includes one or more of ethylene oxide, propylene oxide and butylene oxide.

3. The method for synthesizing the polyether polyol of high molecular weight sucrose according to claim 1, characterized in that: The small molecule alcohol described in step 1) includes one or more of diethylene glycol, propylene glycol, dipropylene glycol or glycerol; the water described is deionized water.

4. The method for synthesizing the polyether polyol of high molecular weight sucrose according to claim 1, characterized in that: The amount of water in the initiator described in step 1) is 1% to 10% of the total mass of the raw materials in step 1), the amount of sucrose in the initiator is 5% to 30% of the total mass of the raw materials in step 1), and the amount of small molecular alcohol in the initiator is 1% to 10% of the total mass of the raw materials in step 1).

5. The method for synthesizing the polyether polyol of high molecular weight sucrose according to claim 1, characterized in that: The amount of the epoxide introduced for the first time in step 1) is 1 to 3 times the total mass of the initiator; the amount of the epoxide introduced again in step 1) is 2 to 5 times the total mass of the initiator.

6. The method for synthesizing the high molecular weight sucrose polyether polyol according to claim 1, characterized in that: The heating in step 1) is to 80-150°C, the polymerization reaction temperature is 80-150°C, and the pressure is 0-0.6MPa; the heating dehydration temperature in step 1) is 90-110°C, and the moisture content is controlled at 0-0.2wt.% of the total mass.

7. The method for synthesizing the high molecular weight sucrose polyether polyol according to claim 1, characterized in that: After the reaction described in step 1) is completed, the amount of water and adsorbent added is 2-10% and 0.1-1% of the total mass of the raw materials in step 1) respectively; after the reaction described in step 2) is completed, the amount of water and adsorbent added is 2-10% and 0.1-1% of the total mass of the raw materials in step 2) respectively.

8. The method for synthesizing the high molecular weight sucrose polyether polyol according to claim 1, characterized in that: The temperature of the heating dehydration in step 2) is 80-150°C and the pressure is 0-0.09MPa; the reaction temperature of the polymerization reaction in step 2) is 130-150°C and the pressure is 0-0.6MPa.

9. The method for synthesizing the high molecular weight sucrose polyether polyol according to claim 1, characterized in that: The amount of the epoxide introduced in step 2) is 10% to 95% of the total mass of the raw materials in step 2).

10. A polyether polyol of high molecular weight sucrose, characterized in that: The compound is prepared by the synthesis method according to any one of claims 1 to 9.

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