A green industrial production method for high-purity polycarbonate-ether polyol and its application

Abstract

A green industrial production method for high-purity polycarbonate-ether polyol and its application. The present invention belongs to the technical field of polyols and their preparation. The purpose of the present invention is to solve the technical problems of large equipment corrosion and high raw material cost in the existing preparation method of polycarbonate-ether polyol. The present invention uses a carboxylic acid with an acidity constant greater than 3 as an initiator, first prepolymerizes it with epoxide under the action of a DMC catalyst, and then copolymerizes the prepolymer with carbon dioxide and epoxide under the action of a catalyst. The carboxylic acid used in the present invention has little corrosion to the reaction equipment, and the raw materials are cheap and easy to obtain. At the same time, it also significantly reduces the content of propylene carbonate in the polycarbonate-ether polyol, and the content of the by-product propylene carbonate is as low as 3.3wt%, which provides the possibility for large-scale industrial production.

Description

Technical Field

[0001] The present invention belongs to the technical field of polyols and their preparation, and particularly relates to a green industrial production method of high-purity polycarbonate-ether polyols and applications thereof. Background Art

[0002] Carbon dioxide is both a greenhouse gas and a carbon and oxygen resource. Since the 1969 report of polymers prepared by reacting carbon dioxide with propylene oxide, the efficient use of this resource has become a hot topic of research. Currently, methods for preparing poly(carbonate-ether) polyols using double metal cyanide (DMC) as a catalyst and carbon dioxide and epoxides as raw materials have been widely reported. Using carbon dioxide as a raw material and reacting it with epoxides to prepare polymer materials is one of the most promising approaches for efficiently utilizing carbon dioxide resources and has attracted considerable attention from researchers.

[0003] Kuyper (US 4826887, US 4826953), Hinz (US 6173599B1) and others reported a method for preparing poly(carbonate-ether) polyols using low molecular weight polypropylene glycol as an initiator, a double metal cyanide based on Zn3[Co(CN)6]2 as a catalyst, and carbon dioxide and propylene oxide as raw materials. In order to pursue higher reaction activity, the polymerization reaction was carried out at a temperature of 110°C or higher, which inevitably led to the disadvantages that the carbonate unit content in the prepared poly(carbonate-ether) polyols was very low (<20%), while the content of the by-product propylene carbonate was very high (>20%). Chinese patent CN201510470795.7 proposes a method for preparing poly(carbonate-ether) polyols. The method proposes using a carboxylic acid with an acidity constant of 0.2 to 4 as an initiator. Before copolymerizing the initiator with carbon dioxide, the initiator is first reacted with an epoxide to activate the epoxide. Then, polyethers of different molecular weights generated in situ after activation are used as chain transfer agents. The chain transfer agent is copolymerized with carbon dioxide and epoxide in the presence of a catalyst. Although this method shortens the polymerization time and improves the selectivity of the polymerization, on the one hand, carboxylic acids with an acidity of less than 4.0 cause severe corrosion to the reaction equipment. On the other hand, the raw materials of carboxylic acids with an acidity of less than 4.0 are not widely available and are relatively expensive. Therefore, it is particularly necessary to develop a green industrial production method for high-purity polycarbonate-ether polyols. Summary of the Invention

[0004] The purpose of the present invention is to solve the technical problems of severe equipment corrosion and high raw material cost in the existing preparation method of polycarbonate-ether polyol, and to provide a green industrial production method of high-purity polycarbonate-ether polyol and its application.

[0005] The purpose of the present invention is to achieve through the following technical solutions:

[0006] One of the objects of the present invention is to provide a green industrial production method for high-purity polycarbonate-ether polyol, which is carried out according to the following steps:

[0007] S1: prepolymerizing a carboxylic acid having an acidity constant greater than 3, a portion of an epoxide, and a portion of a double metal cyanide (DMC) catalyst at a low temperature to obtain a prepolymerized product;

[0008] S2: copolymerizing the prepolymerized product, carbon dioxide, remaining epoxide, and remaining double metal cyanide (DMC) catalyst to obtain a poly(carbonate-ether) polyol.

[0009] It is further defined that the carboxylic acid with an acidity constant greater than 3 in S1 includes one or more of succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanoic acid, terephthalic acid, citric acid, and malic acid.

[0010] It is further defined that the epoxide in S1 includes one or more of alkylene oxide compounds, cycloolefin oxides and epoxy ether compounds having 2 to 20 carbon atoms.

[0011] It is further defined that the epoxide specifically includes one or more of propylene oxide, ethylene oxide, butylene oxide, styrene oxide, cyclopentene oxide, cyclohexene oxide, epichlorohydrin, glycidyl ether, 1,2-epoxyhexane, 1,2-epoxyoctane, 1,2-epoxydecane, 1,2-epoxydodecane, 1,2-epoxytetradecane, and 1,2-epoxyhexadecane.

[0012] It is further defined that the double metal cyanide (DMC) catalyst in S1 is a DMC catalyst based on Zn3[M(CN)6]2, where M=Co, Fe or Ni.

[0013] Further defined, the preparation method of the DMC catalyst based on Zn3[M(CN)6]2:

[0014] Step a): mixing and dissolving tert-butyl alcohol, water and zinc salt to obtain solution a;

[0015] Step b): dissolving a soluble potassium salt in deionized water to obtain a solution b;

[0016] Step c): adding solution b to solution a continuously, stirring for reaction, then centrifuging or filtering for separation, slurry washing, centrifuging again, and finally drying to obtain a Zn3[M(CN)6]2-based DMC catalyst.

[0017] It is further defined that the zinc salt in step a) is one or more of ZnCl2, ZnBr2, Zn(CH3COO)2, Zn(ClCH2COO)2, Zn(Cl2CHCOO)2, Zn(Cl3CHCOO)2, ZnSO4, and Zn(NO3)2.

[0018] It is further defined that the soluble potassium salt in step b) is one or more of K3[Co(CN)6], K3[Fe(CN)6], and K3[Ni(CN)6].

[0019] It is further defined that the reaction temperature in step c) is 20-100°C.

[0020] It is further defined that the molar ratio of carboxylic acid to total epoxides is 1:(10-200).

[0021] It is further defined that the molar ratio of the double metal cyanide (DMC) catalyst to the total epoxide is 1:(500-10000).

[0022] It is further defined that the molar ratio of the carboxylic acid in S1 to the epoxide in S1 is 1:(2-20).

[0023] It is further defined that the double metal cyanide (DMC) catalyst in S1 accounts for 10-100% of the total catalyst mass.

[0024] It is further defined that the double metal cyanide (DMC) catalyst in S1 accounts for 20-80% of the total catalyst mass.

[0025] Most preferably, the double metal cyanide (DMC) catalyst in S1 accounts for 40-60% of the total catalyst mass.

[0026] It is further defined that the temperature of the prepolymerization in S1 is 0-90°C.

[0027] It is further defined that the temperature of the copolymerization reaction in S2 is 0-150°C.

[0028] It is further defined that the temperature of the copolymerization reaction in S2 is 20-120°C.

[0029] Most preferably, the temperature of the copolymerization reaction in S2 is 40-100°C.

[0030] It is further defined that the pressure of the copolymerization reaction in S2 is 0.5 to 10 MPa.

[0031] A second object of the present invention is to provide a high-purity polycarbonate-ether polyol prepared according to the above method, wherein the propylene carbonate content in the high-purity polycarbonate-ether polyol is ≤4.6wt%.

[0032] The third object of the present invention is to provide a high-purity polycarbonate-ether polyol prepared by the above method for use in the fields of leather resin, water-based polyurethane, adhesive, hot melt adhesive, and elastomer.

[0033] It is further defined that the high-purity polycarbonate-ether polyol is used to replace all or part of the traditional polyol in the above-mentioned fields.

[0034] Compared with the prior art, the present invention has the following significant effects:

[0035] The present invention provides a green industrial production method for high-purity polycarbonate-ether polyol. The carboxylic acid used has little corrosion to reaction equipment, and the raw materials are cheap and easily available. At the same time, the content of propylene carbonate in the polycarbonate-ether polyol is significantly reduced, and the content of the byproduct propylene carbonate is as low as 3.3wt%, which makes large-scale industrial production possible. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0037] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, methods, and instruments used are conventional in the art and can be obtained commercially by those skilled in the art unless otherwise specified.

[0038] As used in the following examples, the terms "comprising," "including," "having," "containing," or any other variations thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0039] When amount, concentration or other value or parameter are represented with the range of scope, preferred range or a series of upper preferred value and lower preferred value limit, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value and any range lower limit or preferred value, and no matter whether this scope is disclosed separately.For example, when disclosing scope "1 to 5", described scope should be interpreted as including scope "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5" etc.When numerical range is described in this article, unless otherwise stated, otherwise this scope is intended to include its end value and all integers and fractions within the scope.In this application specification and claims, range limitation can be combined and / or interchanged, and if these ranges are not otherwise stated, include all subranges contained therein.

[0040] The indefinite articles "a" and "an" before the elements or components of the present invention do not limit the quantity requirement (i.e. the number of times they appear). Therefore, "a" or "an" should be interpreted as including one or at least one, and elements or components in the singular also include plural forms, unless the quantity clearly refers to only the singular form.

[0041] The term "one embodiment" or "embodiment" of the present invention refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it necessarily refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0042] The endpoints of the ranges and any values ​​disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed herein.

[0043] Example 1

[0044] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0045] Step 1: Preparation of DMC catalyst:

[0046] Step a): 11.42 g of ZnCl2 was dissolved in 30 ml of tert-butanol and 60 ml of water to obtain solution a;

[0047] Step b): dissolving 1.32 g of K3[Co(CN)6] in 20 ml of deionized water to obtain solution b;

[0048] Step c): Solution b is continuously added to solution a, stirred and reacted at 50° C., and then centrifuged. The sediment is slurried and washed six times with a mixture of tert-butanol and water in varying proportions. After each wash, it is centrifuged. Finally, the sediment after centrifugation is dried in a vacuum oven at 60° C. to obtain a DMC catalyst based on Zn3[Co(CN)6]2.

[0049] Step 2: Pre-polymerization:

[0050] 0.84 g of catalyst and 140.0 g of terephthalic acid initiator were added to a 500 ml reactor. The reactor was evacuated and filled with CO2 for 2 h (6 times) at 80°C, and then cooled to room temperature. 100 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm and prepolymerized at 90°C for 4 h. After the reaction, the reactor was cooled to room temperature in a cold water bath at 25°C, and the unreacted propylene oxide was evaporated to obtain 235 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0051] Step 3: Copolymerization:

[0052] 0.18g catalyzer and 34g above-mentioned prepolymer are joined in 500ml reactor respectively, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 2.0Mpa, polymerization reaction temperature 90 ℃, reaction times 6h.After reaction finishes, reactor temperature is 25 ℃ cold water bath and is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 210g.

[0053] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2200 g / mol, a molecular weight distribution of 1.36, and a propylene carbonate content of 4.6 wt%.

[0054] Example 2

[0055] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0056] Step 1: Preparation of DMC catalyst: see Example 1.

[0057] Step 2: Pre-polymerization:

[0058] 0.84 g of catalyst and 56 g of terephthalic acid initiator were added to a 500 ml reactor. The reactor was evacuated and filled with CO2 for 2 h (6 times) at 80°C, and then cooled to room temperature. 200 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm and prepolymerized at 90°C for 4 h. After the reaction, the reactor was cooled to room temperature in a cold water bath at 25°C, and the unreacted propylene oxide was evaporated to obtain 252 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0059] Step 3: Copolymerization:

[0060] 0.18g catalyzer and 90g above-mentioned prepolymer are joined in 500ml reactor respectively, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 2.0Mpa, polymerization reaction temperature 80 ℃, reaction times 6h.After reaction finishes, reactor temperature is 25 ℃ cold water bath and is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 308g.

[0061] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2900 g / mol, a molecular weight distribution of 1.46, and a propylene carbonate content of 4.3 wt%.

[0062] Example 3

[0063] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0064] Step 1: Preparation of DMC catalyst: see Example 1.

[0065] Step 2: Pre-polymerization:

[0066] 0.75 g of catalyst and 150.0 g of sebacic acid initiator were added to a 500 ml reactor. The mixture was evacuated and filled with CO2 for 2 h (6 times) at 80°C, and then cooled to room temperature. 180 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm for 4 h at 80°C. After the reaction, the reactor was cooled to room temperature in a 25°C cold water bath, and the unreacted propylene oxide was evaporated to obtain 322 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0067] Step 3: Copolymerization:

[0068] 0.15g catalyzer and 65g above-mentioned prepolymer are joined in the 500ml reactor respectively, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 4.0Mpa, 70 ℃ of polymerization reaction temperature, reaction times 6h.After reaction finishes, reactor temperature is that 25 ℃ cold water bath is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 328g.

[0069] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2300 g / mol, a molecular weight distribution of 1.46, and a propylene carbonate content of 3.6 wt%.

[0070] Example 4

[0071] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0072] Step 1: Preparation of DMC catalyst: see Example 1.

[0073] Step 2: Pre-polymerization:

[0074] 0.225 g of catalyst and 37.5 g of sebacic acid initiator were added to a 500 ml reactor. The mixture was evacuated and filled with CO2 for 2 h (6 times) at 80°C, and then cooled to room temperature. 180 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm for prepolymerization at 60°C for 8 h. After the reaction, the reactor was cooled to room temperature in a 25°C cold water bath, and the unreacted propylene oxide was evaporated to obtain 215 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0075] Step 3: Copolymerization:

[0076] 0.06g catalyzer and 85g above-mentioned prepolymer are joined in 500ml reactor respectively, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 100g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 4.0Mpa, polymerization reaction temperature 70 ℃, reaction times 6h.After reaction finishes, reactor temperature is 25 ℃ cold water bath and is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 210g.

[0077] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 3300 g / mol, a molecular weight distribution of 1.36, and a propylene carbonate content of 3.3 wt%.

[0078] Example 5

[0079] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0080] Step 1: Preparation of DMC catalyst: see Example 1.

[0081] Step 2: Pre-polymerization:

[0082] 0.45 g of catalyst and 60.0 g of adipic acid initiator were added to a 500 ml reactor. The mixture was evacuated and filled with CO2 for 2 h (6 times) at 80°C, and then cooled to room temperature. 150 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm and prepolymerized at 90°C for 4 h. After the reaction, the reactor was cooled to room temperature in a 25°C cold water bath, and unreacted propylene oxide was evaporated to obtain 208 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0083] Step 3: Copolymerization:

[0084] 0.15g catalyzer and 70g above-mentioned prepolymer are joined in 500ml reactor respectively, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, pass into carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 3.0Mpa, polymerization reaction temperature 70 ℃, reaction time 6h.After reaction finishes, reactor temperature is 25 ℃ cold water bath and is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 310g.

[0085] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2600 g / mol, a molecular weight distribution of 1.26, and a propylene carbonate content of 4.5 wt%.

[0086] Example 6

[0087] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0088] Step 1: Preparation of DMC catalyst: see Example 1.

[0089] Step 2: Pre-polymerization:

[0090] 0.3 g of catalyst and 20.0 g of adipic acid initiator were added to a 500 ml reactor. The mixture was evacuated and filled with CO2 at 80°C for 2 h (6 times), then cooled to room temperature. 160 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm for prepolymerization at 90°C for 4 h. After the reaction, the reactor was cooled to room temperature in a 25°C cold water bath, and unreacted propylene oxide was evaporated to obtain 178 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0091] Step 3: Copolymerization:

[0092] Above-mentioned 89g prepolymer is joined in the 500ml reactor, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 1.0Mpa, polymerization reaction temperature 70 ℃, reaction times 8h.After reaction finishes, reactor temperature is 25 ℃ cold water bath and is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 350g.

[0093] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 5600 g / mol, a molecular weight distribution of 1.56, and a propylene carbonate content of 4.1 wt%.

[0094] Example 7

[0095] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0096] Step 1: Preparation of DMC catalyst: see Example 1.

[0097] Step 2: Pre-polymerization:

[0098] 0.45 g of catalyst and 60.0 g of adipic acid initiator were added to a 500 ml reactor. The reactor was evacuated and filled with CO2 for 2 h (6 times) at 100°C, and then cooled to room temperature. 100 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm for prepolymerization at 60°C for 8 h. After the reaction, the reactor was cooled to room temperature in a 25°C cold water bath, and the unreacted propylene oxide was evaporated to obtain 158 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0099] Step 3: Copolymerization:

[0100] 0.15g catalyzer and 20g above-mentioned prepolymer are joined in the 500ml reactor respectively, under 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 50g propylene oxide, stir with the rotating speed of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in thermostatic bath and carries out polyreaction.Polymeric carbon dioxide pressure is 3.0Mpa, and polymerization reaction temperature is 80 ℃, after reaction time 1h, 50g prepolymer and 150g propylene oxide are continuously added in the reactor with obstruction pump respectively, and prepolymer feed rate is 8.3g / h, and propylene oxide feed rate is 25g / h.Continue reaction 1 hour after propylene oxide feeding is complete. After the reaction, the reactor was cooled to room temperature using a cold water bath at 25° C., unreacted propylene oxide was evaporated, and the residue was dried in a vacuum oven at 40° C. to constant weight, thereby obtaining 308 g of a polymer.

[0101] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2800 g / mol, a molecular weight distribution of 1.21, and a propylene carbonate content of 4.2 wt%.

[0102] Example 8

[0103] The green industrial production method of high-purity polycarbonate-ether polyol of this embodiment is carried out by the following steps:

[0104] Step 1: Preparation of DMC catalyst: see Example 1.

[0105] Step 2: Pre-polymerization:

[0106] 0.45 g of catalyst and 60.0 g of adipic acid initiator were added to a 500 ml reactor. The reactor was evacuated and filled with CO2 for 2 h (6 times) at 100°C, and then cooled to room temperature. 100 g of propylene oxide was added to the reactor, and the mixture was stirred at 500 rpm for prepolymerization at 60°C for 8 h. After the reaction, the reactor was cooled to room temperature in a 25°C cold water bath, and the unreacted propylene oxide was evaporated to obtain 158 g of prepolymer, which was stored in a sealed bottle in a desiccator for later use.

[0107] Step 3: Copolymerization:

[0108] 0.15g catalyzer and 70g above-mentioned prepolymer are joined in the 500ml reactor respectively, under 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 50g propylene oxide, stir with the rotating speed of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 3.0Mpa, and 80 ℃ of polymerization reaction temperature, after 3 hours reaction times, 150g propylene oxide is continuously added in the reactor with blocking pump, and adding rate is 25g / h.Propylene oxide feed finishes and continues reaction 1 hour after.After reaction finishes, reactor temperature is that 25 ℃ cold water bath is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 303g.

[0109] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2730 g / mol, a molecular weight distribution of 1.23, and a propylene carbonate content of 4.3 wt%.

[0110] Comparative Example 1

[0111] The preparation method of the polycarbonate-ether polyol of the present embodiment is carried out according to the following steps:

[0112] Step 1: Preparation of DMC catalyst: see Example 1.

[0113] Step 2: Copolymerization (without prepolymerization):

[0114] 0.3g catalyzer and 20.0g terephthalic acid initiator are joined respectively in the 500ml reactor, under 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, feed carbon dioxide by carbon dioxide pressure regulator, reactor is placed in thermostatic bath and carries out polyreaction.Polymeric carbon dioxide pressure is 2.0Mpa, 90 ℃ of polymerization reaction temperatures, reaction times 6h.After reaction finishes, reactor temperature is that 25 ℃ cold water bath is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 205g.

[0115] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2100 g / mol, a molecular weight distribution of 1.35, and a propylene carbonate content of 9.6%.

[0116] Comparative Example 2

[0117] The preparation method of the polycarbonate-ether polyol of the present embodiment is carried out according to the following steps:

[0118] Step 1: Preparation of DMC catalyst: see Example 1.

[0119] Step 2: Copolymerization (without prepolymerization):

[0120] 0.3g catalyzer and 30.0g sebacic acid initiator are joined in the 500ml reactor respectively, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, pass into carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 4.0Mpa, 80 ℃ of polymerization reaction temperature, reaction times 8h.After reaction finishes, reactor temperature is 25 ℃ cold water bath and is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 227g.

[0121] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2300 g / mol, a molecular weight distribution of 1.45, and a propylene carbonate content of 8.7%.

[0122] Comparative Example 3

[0123] The preparation method of the polycarbonate-ether polyol of the present embodiment is carried out according to the following steps:

[0124] Step 1: Preparation of DMC catalyst: see Example 1.

[0125] Step 2: Copolymerization (without prepolymerization):

[0126] 0.3g catalyzer and 20.0g adipic acid initiator are joined in the 500ml reactor respectively, at 80 ℃, through evacuating and filling CO2 process 2h (inflation 6 times), and cool to room temperature, in described reactor, add 200g propylene oxide, with the rotating speed stirring of 500rpm, in reactor, pass into carbon dioxide by carbon dioxide pressure regulator, reactor is placed in constant temperature bath and carries out polyreaction.Polymeric carbon dioxide pressure is 2.0Mpa, 80 ℃ of polymerization reaction temperature, reaction times 10h.After reaction finishes, reactor temperature is 25 ℃ cold water bath and is cooled to room temperature, steams and removes unreacted propylene oxide, and residuum is dried to constant weight in 40 ℃ of vacuum drying ovens, thereby obtains polymkeric substance 237g.

[0127] The poly(carbonate-ether) polyol prepared in this example was analyzed using GPC and NMR. The polymer had a number average molecular weight of 2080 g / mol, a molecular weight distribution of 1.42, and a propylene carbonate content of 25.8%.

[0128] Comparative Example 4

[0129] The difference between this comparative example and Example 1 is that no catalyst is added during the second step of prepolymerization. No reaction occurs during the prepolymerization stage.

[0130] Analysis shows that when a carboxylic acid with a carboxylic acid degree greater than 3 is selected, during the prepolymerization stage, due to the weak acidity of the carboxylic acid and the absence of a catalyst, it hardly reacts chemically with propylene oxide at 100°C. When the temperature rises to 100-150°C, the carboxylic acid will react with the diol generated during the reaction to undergo an alcohol-acid condensation, while also generating water. These side reaction products are detrimental to the subsequent copolymerization, and the catalytic activity and selectivity of the prepared poly(carbonate-ether) polyol are greatly reduced, or even the copolymerization cannot proceed.

[0131] The foregoing are merely preferred embodiments of the present invention. These embodiments are all different implementations based on the overall concept of the present invention. The scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A green industrial production method for high-purity polycarbonate-ether polyol, characterized in that: Follow these steps: S1: prepolymerizing a carboxylic acid having an acidity constant greater than 3, a portion of an epoxide, and a portion of a DMC catalyst at a low temperature to obtain a prepolymerized product; S2: copolymerizing the prepolymerized product, carbon dioxide, remaining epoxide and remaining DMC catalyst to obtain a poly(carbonate-ether) polyol.

2. The method according to claim 1, characterized in that The carboxylic acid having an acidity constant greater than 3 in S1 includes one or more of succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, citric acid, and malic acid; the epoxide includes one or more of alkylene oxides, cycloolefin oxides, and epoxy ether compounds having 2 to 20 carbon atoms; and the DMC catalyst is a Zn3[M(CN)6]2-based DMC catalyst, where M=Co, Fe, or Ni.

3. The method according to claim 2, characterized in that Epoxides specifically include one or more of propylene oxide, ethylene oxide, butylene oxide, styrene oxide, cyclopentene oxide, cyclohexene oxide, epichlorohydrin, glycidyl ether, 1,2-epoxyhexane, 1,2-epoxyoctane, 1,2-epoxydecane, 1,2-epoxydodecane, 1,2-epoxytetradecane, and 1,2-epoxyhexadecane.

4. The method according to claim 2, characterized in that Preparation method of DMC catalyst based on Zn3[M(CN)6]2: Step a): mixing and dissolving tert-butyl alcohol, water and zinc salt to obtain solution a; Step b): dissolving a soluble potassium salt in deionized water to obtain a solution b; Step c): adding solution b to solution a continuously, stirring for reaction, then centrifuging or filtering for separation, slurry washing, centrifuging again, and finally drying to obtain a Zn3[M(CN)6]2-based DMC catalyst.

5. The method according to claim 4, characterized in that In step a), the zinc salt is one or more of ZnCl2, ZnBr2, Zn(CH3COO)2, Zn(ClCH2COO)2, Zn(Cl2CHCOO)2, Zn(Cl3CHCOO)2, ZnSO4, and Zn(NO3)2; in step b), the soluble potassium salt is one or more of K3[Co(CN)6], K3[Fe(CN)6], and K3[Ni(CN)6]; and in step c), the reaction temperature is 20-100°C.

6. The method according to claim 1, characterized in that The molar ratio of carboxylic acid to total epoxides is 1:(10-200), the molar ratio of DMC catalyst to total epoxides is 1:(500-10000), the molar ratio of carboxylic acid in S1 to epoxides in S1 is 1:(2-20), and the DMC catalyst in S1 accounts for 20-80% of the total catalyst mass.

7. The method according to claim 1, characterized in that The temperature of the prepolymerization in S1 is 0-90°C.

8. The method according to claim 1, characterized in that The temperature of the copolymerization reaction in S2 is 0-150°C and the pressure is 0.5~10MPa.

9. The high-purity polycarbonate-ether polyol prepared by the method according to any one of claims 1 to 8, characterized in that: The propylene carbonate content is ≤4.6wt%.

10. Application of the high-purity polycarbonate-ether polyol prepared by the method according to any one of claims 1 to 8 in the fields of leather resin, water-based polyurethane, adhesive, hot melt adhesive, and elastomer.