Preparation method of low-odor high-molecular-weight high-activity polyether polyol

Abstract

The invention discloses a preparation method of low-odor high-molecular-weight high-activity polyether polyol, ethylene oxide terminated high-molecular-weight high-activity crude polyether polyol is prepared by adopting a step-by-step polymerization method, and organic acid is adopted as a refining agent of the polyether polyol, so that the odor of a polyether product can be effectively removed; the hydroxyl value of the polyether polyol is 8-70 mgKOH / g, and the polyether polyol is low in odor and high in activity.

Description

Technical Field

[0001] The invention relates to a method for preparing a low-odor, high-molecular-weight and high-activity polyether polyol, belonging to the technical field of organic synthesis. Background Art

[0002] The invention adopts a step-by-step polymerization method to prepare ethylene oxide terminated high molecular weight high activity crude polyether polyol, and adopts organic acid as a polyether polyol refining agent, which can effectively remove the odor of the polyether product.

[0003] Traditional polyether polyol production uses alkali metal compounds as catalysts. After the polymerization reaction is completed, a neutralizer needs to be added to remove the alkali metal compounds. This process is called the refining process of polyether polyols. The introduction of neutralizers in the refining process will bring odor to the polyether product. Therefore, many studies have made changes at this stage in order to reduce the odor of polyether products.

[0004] CN109438691A reports a method for preparing low-odor polyether polyols. Polyol compounds are used as initiators, and potassium hydroxide is used as a catalyst to react at a pressure of 0-0.4 MPa and a temperature of 80-140°C. -1 The propylene oxide treated by molecular sieve tank for adsorption and formaldehyde reduction is polymerized step by step and terminated with ethylene oxide to obtain a crude polyether. After neutralization and adsorption, an isopropanol aqueous solution is added to the crude polyether, and the reaction is carried out at 60-80°C for 30 minutes. Low-odor polyether polyols are obtained by reduced pressure distillation; wherein, the polyol compound is 1%-16%, propylene oxide is 67.5%-90.8%, ethylene oxide is 8%-16%, and alkali metal hydroxide is 0.2%-0.5%. The odor level of the obtained polyether polyol product is ≤2.5, and the environmental protection performance is good.

[0005] CN108484896A introduces a method for preparing a low-VOC, high-activity, high-molecular-weight polyether polyol. Glycerol is used as an initiator, and a polymerization reaction is carried out with propylene oxide under the action of a low-alkali content catalyst, and then ethylene oxide is used for end-capping. The high-activity, high-molecular-weight polyether polyol catalyzed by the low-alkali content is added to a closed reactor, deionized water and a highly efficient refined adsorbent are added, nitrogen is replaced, mixed, refined, and adsorbed at a certain temperature, and then dehydrated and filtered to obtain a low-VOC, high-activity, high-molecular-weight polyether polyol product. The invention simplifies the process flow, does not use an acid neutralization process, avoids the generation of aldehyde substances in the neutralization process, and uses a highly efficient refined adsorbent to effectively adsorb aldehydes and other impurities generated in the production process of polyether polyols, and finally achieves the purpose of reducing the VOC content in polyether polyols. It is suitable for use as a method for preparing a low-VOC, high-activity, high-molecular-weight polyether polyol.

[0006] CN108059717A introduces a refining method for low-odor polyether polyol and its application. The refining method comprises the following steps: 1. adding water and a compound antioxidant to a crude polyether polyol; 2. neutralizing with a neutralizer, and then adding an adsorbent for adsorption; 3. dehydrating under negative pressure and filtering to obtain a refined polyether polyol; wherein the crude polyether polyol is a polyether polyol synthesized using an alkali metal catalyst, and the compound antioxidant comprises an antioxidant 1010 and an antioxidant DPDP. The refining method of the invention can effectively reduce the odor of the polyether and remove the alkali metal catalyst to the maximum extent. Summary of the invention

[0007] The invention discloses a method for preparing a low-odor, high-molecular-weight, high-activity polyether polyol. The method adopts a step-by-step polymerization method to prepare a high-molecular-weight, high-activity crude polyether polyol terminated with ethylene oxide, and adopts an organic acid as a polyether polyol refining agent, so as to effectively remove the odor of the polyether product, and finally obtain a high-activity polyether polyol with a hydroxyl value of 8-70 mgKOH / g and a low odor.

[0008] In one aspect, the present invention provides a method for preparing a polyether polyol, comprising the steps of:

[0009] S1 Preparation of intermediate 1: A small molecular weight polyol compound is used as a starting polymer, contacted with a first portion of an alkali metal catalyst, and subjected to ring-opening addition polymerization of one or more epoxy compounds I at a temperature of 110 to 130° C. to obtain an intermediate 1 having a hydroxyl value of 55 to 300 mgKOH / g;

[0010] S2 Preparation of intermediate 2: contacting the intermediate 1 with a second portion of an alkali metal catalyst, and performing ring-opening addition polymerization at a temperature of 110 to 130° C. to generate one or more epoxy compounds II, thereby obtaining an intermediate 2 having a hydroxyl value of 20 to 180 mgKOH / g;

[0011] S3 Preparation of intermediate 3: The intermediate 2 is contacted with a third alkali metal catalyst, and subjected to ring-opening addition polymerization at a temperature of 110 to 130° C. to generate one or more epoxy compounds III, thereby obtaining an intermediate 3 having a hydroxyl value of 10 to 100 mgKOH / g;

[0012] Preparation of S4 polyether polyol: The intermediate 3 is mixed with ethylene oxide, and the intermediate 3 is subjected to ring-opening polymerization of ethylene oxide at a temperature of 100 to 130° C. to perform end-capping treatment to obtain the polyether polyol.

[0013] The starting polymer in the present invention includes alcohol compounds, sugars and the like.

[0014] Alcohol compounds include divalent alcohols such as water, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-propylene glycol, 1,4-cyclohexanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, and 1,4-cyclohexanediol; and polyvalent alcohols such as glycerol, trimethylol propane, pentaerythritol, dipentaerythritol, tripentaerythritol, and polyglycidol.

[0015] The sugars include glucose, sorbitol, dextrose, levulose, sucrose, methyl glucoside, hydroxyethyl glucoside and the like sugars or their derivatives.

[0016] Optionally, the small molecule polyol compound is selected from at least one of ethylene glycol, 1,2-propylene glycol, glycerol, pentaerythritol, sorbitol, mannitol, and sucrose.

[0017] Optionally, in S1, the mass ratio of the small molecule alcohol compound, the first alkali metal catalyst, and the epoxy compound I is in the range of 1:0.005-0.17:5-10.

[0018] Optionally, in S2, the mass ratio of the intermediate 1, the second alkali metal catalyst, and the epoxy compound II is in the range of 1:0.003-0.1:0.5-6.

[0019] Optionally, in S3, the mass ratio of the intermediate 2, the third alkali metal catalyst, and the epoxy compound III is in the range of 1:0.002-0.1:0.5-6.

[0020] Optionally, in S4, the mass ratio of the intermediate 3 to ethylene oxide is in the range of 1:0.08 to 0.5.

[0021] Optionally, the epoxy compound I, epoxy compound II, and epoxy compound III are each independently selected from at least one of propylene oxide, ethylene oxide, butylene oxide, styrene oxide, cyclohexene oxide, epichlorohydrin, epibromohydrin, methyl glycidyl ether, allyl glycidyl ether, and the like.

[0022] The epoxy compounds added in the intermediate preparation process of the present invention include propylene oxide, ethylene oxide, butylene oxide, styrene oxide, cyclohexene oxide, epichlorohydrin, epibromohydrin, methyl glycidyl ether, allyl glycidyl ether, etc. Two or more epoxides can also be used in combination. Among them, propylene oxide, ethylene oxide, butylene oxide, and styrene oxide are preferred, and propylene oxide and ethylene oxide are more preferred. In the manufacture of alkoxylated compounds, propylene oxide is most preferably used.

[0023] In the step-by-step addition polymerization, the alkali metal catalyst is added in each step to ensure that the amount is 0.002%-0.17% based on the initiator or intermediate in the addition polymerization stage. Since epoxy compounds are easily isomerized to form double-bonded substances in an alkaline environment, and further oxidized to form aldehyde substances under heating conditions. Adding the alkali metal catalyst required for synthesizing the target polyether polyol in steps can reduce the amount of alkaline substances in the environment during the polymerization process and effectively inhibit the generation of aldehyde substances during the addition polymerization reaction.

[0024] The maximum pressure during the addition polymerization of the epoxy compound is preferably below 0.8 MPa(G). When the maximum pressure of the epoxy compound exceeds 0.8 MPa(G), the content of the monoalcohol (total unsaturation) as a by-product of propylene oxide increases. The maximum reaction pressure is preferably below 0.6 MPa(G), and most preferably below 0.5 MPa(G). The epoxy compound can be supplied to the polymerization system in batches or in a continuous manner.

[0025] Optionally, the amount of the alkali metal catalyst is a calculated value, and the total mass of the alkali metal is 0.078% to 0.26% of the small molecule polyol.

[0026] Optionally, the alkali metal catalyst is selected from at least one of NaOH, KOH, and NaH.

[0027] Optionally, the end-capping treatment is performed in a nitrogen environment with a nitrogen pressure of 0.01 MPa to 0.4 MPa.

[0028] Optionally, the end-capping treatment obtains an end-capping product; the method further comprises a step of refining the end-capping product; the refining step comprises sequentially performing an organic acid treatment and an inorganic acid treatment.

[0029] Optionally, the organic acid is selected from at least one of cyclopentanoic acid, cyclohexanoic acid, oxalic acid, adipic acid, cyclohexanediacid, and cyclopentanoic acid.

[0030] Optionally, the inorganic acid is selected from at least one of phosphoric acid, hydrochloric acid and sulfuric acid.

[0031] Optionally, the organic acid is used to neutralize the alkali metal catalyst in the capped product.

[0032] Optionally, the mass ratio of the organic acid to the end-capping product is 1:115-440.

[0033] Optionally, the inorganic acid is used to regulate the pH value; the pH is adjusted to 5.2-7.0.

[0034] Optionally, the hydroxyl value of the polyether polyol is 8 to 70 mgKOH / g.

[0035] Optionally, it is used in the preparation of polyurethane or as a lubricant, brake fluid, or resin modifier;

[0036] The polyurethane is selected from at least one of semi-rigid and soft polyurethane foams, coatings, adhesives, bed materials, waterproof materials, elastomers, sealants, and soles.

[0037] The ethylene oxide capping reaction is carried out in the presence of nitrogen, which can effectively avoid the occurrence of homopolymerization caused by the high activity of ethylene oxide, resulting in insufficient primary hydroxyl groups in the product. The nitrogen pressure is 0.01MPa-0.4MPa, preferably 0.05-0.1MPa.

[0038] After the addition of epoxide, the internal pressure of the polymerization reactor will slowly decrease, and the reaction is controlled based on the hydroxyl value of the polyether polyol. The polymerization is generally carried out until the hydroxyl value is 8 to 120 mgKOH / g.

[0039] When the polyether polyol is produced by the above method, after the epoxide polymerization is completed, a polyether polyol containing a catalyst (hereinafter referred to as a crude polyol) is obtained, and it is usually necessary to remove the catalyst in the crude polyol.

[0040] The final product uses a refining agent to remove the alkali metal catalyst, but the refining process of the present invention is different from the inorganic acid neutralization in the traditional polyether refining process. The method of using organic acid neutralization and inorganic acid to control the pH value can effectively avoid the unique odor and side reactions caused by the introduction of phosphoric acid in the neutralization process of the traditional process. The organic acid includes one or a mixture of cyclopentanoic acid, cyclohexanoic acid, oxalic acid, adipic acid, cyclohexanedicarboxylic acid, etc., and the inorganic acid includes phosphoric acid, hydrochloric acid, sulfuric acid, etc. The total amount of organic acid and inorganic acid is 1-3% based on the amount of polyether polyol product, preferably 1-1.5%, and the contact temperature is preferably in the range of 50 to 130°C.

[0041] Different from the prior art, the present invention adopts a step-by-step polymerization method to prepare ethylene oxide-terminated high-molecular-weight and high-activity crude polyether polyols. It is found that the use of inorganic acid (mainly phosphoric acid) adopted in the traditional neutralization process will bring a strong odor to the polyether polyol product. Organic acid is used as a refining agent instead, and the inorganic acid is used to adjust the pH value of the product. This method can effectively remove the odor of the polyether product.

[0042] In the method for producing the polyether polyol of the present invention, the odor in the polyol is effectively reduced, and a polyol with a lower odor is obtained. The polyether polyol produced by the method of the present invention can be widely used in polyurethane fields such as semi-rigid and soft polyurethane foams, coatings, adhesives, bed materials, waterproof materials, elastomers, sealants, soles, etc., and can also be used in lubricants, brake fluids, resin modifiers and other fields. DETAILED DESCRIPTION

[0043] Example 1 Preparation of polyether polyol A

[0044] Preparation of intermediate 1: 200 g of ethylene glycol and 1.27 g of KOH were added to a pressure-resistant autoclave (hereinafter referred to as the autoclave) equipped with a stirrer, a temperature controller, a pressure gauge, a nitrogen inlet pipe and a monomer inlet pipe, and the air therein was replaced with nitrogen. Then, 1006.5 g of propylene oxide was added in batches (10-15 batches, each batch not exceeding 100 g) at a polyaddition temperature of 110° C. and a maximum reaction pressure of 0.3 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the autoclave was controlled to be 110° C. to 120° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 665 kPa for 30 min to obtain intermediate 1.

[0045] Preparation of Intermediate 2: 200 g of Intermediate 1 and 0.84 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 800 g of propylene oxide was added in batches (8-15 batches, each batch not exceeding 100 g) at a polyaddition temperature of 110° C. and a maximum reaction pressure of 0.3 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 110° C.-120° C. and maintained for 2-3 hours, and the reaction was terminated. Then, the reaction mixture was treated under reduced pressure at the same temperature and 665 kPa for 30 min to obtain Intermediate 2.

[0046] Preparation of Intermediate 3: 200 g of Intermediate 2 and 1.37 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 968 g of propylene oxide was added in batches (10-15 batches, each batch not exceeding 100 g) at a polyaddition temperature of 110° C. and a maximum reaction pressure of 0.3 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 110° C.-120° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 665 kPa for 30 minutes to obtain Intermediate 3.

[0047] Preparation of crude polyether polyol A: 200 g of intermediate 3 was added to an automatic autoclave, the air therein was replaced with nitrogen, N2 was charged into the autoclave to make the pressure in the autoclave reach 0.1 MPa, and then 75 g of ethylene oxide was added in 3-5 batches at a polyaddition temperature of 110°C and a maximum reaction pressure of 0.3 MPa (under standard atmospheric pressure). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 110°C-120°C and maintained for 2-3 hours to terminate the reaction. Then, at the same temperature, the pressure was reduced at 665 kPa for 30 minutes to obtain crude polyether polyol A.

[0048] Purification of polyether polyol A: 500 g of crude polyether polyol A was added to an automatic autoclave, and 1.14 g of cyclohexane acid was added as a purifying agent at 50°C for purification. The mixture was stirred for 1 hour, and then 0.02 g to 0.03 g of hydrochloric acid was added to adjust the pH value of the polyether polyol to between 5.2 and 6.0. The solid salt was removed by filtration to obtain polyether polyol AA.

[0049] Example 2 Preparation of polyether polyol B

[0050] Preparation of Intermediate 1: 400 g of 1,2-propylene glycol and 7.77 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 3290 g of propylene oxide was added in batches (33-50 batches, each batch not exceeding 100 g) at a polyaddition temperature of 130° C. and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130° C.-135° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 550 kPa for 30 min to obtain Intermediate 1.

[0051] Preparation of Intermediate 2: 400 g of Intermediate 1 and 2.74 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 1307 g of propylene oxide was added in batches (14-25 batches, each batch not exceeding 100 g) at a polyaddition temperature of 130° C. and a maximum reaction pressure of 0.3 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130° C.-135° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 550 kPa for 30 min to obtain Intermediate 2.

[0052] Preparation of Intermediate 3: 400 g of Intermediate 2 and 1.79 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 652 g of propylene oxide was added in batches (7-15 batches, each batch not exceeding 100 g) at a polyaddition temperature of 130° C. and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130° C.-135° C. and maintained for 2-3 hours to terminate the reaction. Then, at the same temperature, the decompression treatment was carried out at 550 kPa for 30 min to obtain Intermediate 3.

[0053] Preparation of crude polyether polyol B: 200 g of intermediate 3 was added to an automatic autoclave, the air therein was replaced with nitrogen, N2 was charged into the autoclave to make the pressure inside the autoclave reach 0.2 MPa, and then 50 g of ethylene oxide was added in batches (in 3-5 batches) at a polyaddition temperature of 130°C and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 2-3 hours, and the reaction was terminated. Then, the crude polyether polyol B was obtained by decompression treatment at the same temperature and 550 kPa for 30 minutes.

[0054] Purification of polyether polyol B: 500 g of crude polyether polyol B was added to an automatic autoclave, 1.62 g of oxalic acid and 3 g of deionized water were added at 70°C and stirred for 1 hour, then 0.05 g to 0.1 g of phosphoric acid was added, the pH value of the polyether polyol was adjusted to between 5.5 and 6.5, and solid salts were removed by filtration to obtain polyether polyol B.

[0055] Example 3 Preparation of polyether polyol C

[0056] Preparation of Intermediate 1: 300 g of glycerol and 5.1 g of KOH were added to an automatic autoclave, and the air therein was replaced with nitrogen. Then, 2928 g of propylene oxide was added in batches (30-50 batches, each batch not exceeding 100 g) at a polyaddition temperature of 120° C. and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 120° C.-130° C. and maintained for 1-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 650 kPa for 30 minutes to obtain Intermediate 1.

[0057] Preparation of Intermediate 2: 300 g of Intermediate 1 and 0.99 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 627 g of propylene oxide was added in batches (7-15 batches, each batch not exceeding 100 g) at a polyaddition temperature of 120° C. and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 120° C.-130° C. and maintained for 1-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 650 kPa for 30 minutes to obtain Intermediate 2.

[0058] Preparation of Intermediate 3: 300 g of Intermediate 2 and 0.99 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 527 g of propylene oxide was added in batches (6-15 batches, each batch not exceeding 100 g) at a polyaddition temperature of 120° C. and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 120° C.-130° C. and maintained for 1-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 650 kPa for 30 minutes to obtain Intermediate 3.

[0059] Preparation of crude polyether polyol C: 300 g of intermediate 3 was added to an automatic autoclave, the air therein was replaced with nitrogen, N2 was charged into the autoclave to make the pressure in the autoclave reach 0.15 MPa, and then 50 g of ethylene oxide was added in batches (in 3-5 batches) at a polyaddition temperature of 130°C and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 1-3 hours, and the reaction was terminated. Then, the reaction was treated under reduced pressure at the same temperature and 650 kPa for 30 minutes to obtain crude polyether polyol C.

[0060] Refining of polyether polyol C: 500 g of crude polyether polyol C was added to an automatic autoclave, 1.97 g of adipic acid and 6 g of deionized water were added at 90°C and stirred for 1 hour, then 0.05 g to 0.1 g of phosphoric acid was added, the pH value of the polyether polyol was adjusted to between 5.5 and 6.5, dehydrated to a water content of no more than 0.04%, filtered to remove solid salts, and polyether polyol C was obtained.

[0061] Example 4 Preparation of polyether polyol D

[0062] Preparation of Intermediate 1: 500 g of pentaerythritol and 6.59 g of KOH were added to an automatic autoclave, and the air therein was replaced with nitrogen. Then, 3167 g of propylene oxide was added in batches (32-50 batches, each batch not exceeding 100 g) at a polyaddition temperature of 115° C. and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 115° C.-125° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 600 kPa for 30 minutes to obtain Intermediate 1.

[0063] Preparation of Intermediate 2: 500 g of Intermediate 1 and 3.58 g of KOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 2000 g of propylene oxide was added in batches (20-40 batches, each batch not exceeding 100 g) at a polyaddition temperature of 115° C. and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 115° C.-125° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 600 kPa for 30 minutes to obtain Intermediate 2.

[0064] Preparation of Intermediate 3: 500 g of Intermediate 2 and 1.28 g of KOH were added to an autoclave, the air therein was replaced with nitrogen, and then 680 g of propylene oxide was added in batches (7-15 batches, each batch not exceeding 100 g) at a polyaddition temperature of 115° C. and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the autoclave was controlled to be 115° C.-125° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 600 kPa for 30 minutes to obtain Intermediate 3.

[0065] Preparation of crude polyether polyol D: 500 g of intermediate 3 was added to an automatic autoclave, the air therein was replaced with nitrogen, N2 was charged into the autoclave to make the pressure in the autoclave reach 0.1 MPa, and then 40 g of ethylene oxide was added in batches (in 3-5 batches) at a polyaddition temperature of 130°C and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 2-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 600 kPa for 30 minutes to obtain crude polyether polyol D.

[0066] Refining of polyether polyol D: 500 g of crude polyether polyol D was added to an automatic autoclave, 2.62 g of cyclohexanedicarboxylic acid and 5 g of deionized water were added and stirred for 1 h at 100 ° C, and then 0.02 g-0.03 g of hydrochloric acid was added to adjust the pH value of the polyether polyol to between 5.2 and 6.2, and dehydrated to a water content of no more than 0.04%, and solid salts were removed by filtration to obtain polyether polyol D.

[0067] Example 5 Preparation of polyether polyol E

[0068] Preparation of Intermediate 1: 300 g of sorbitol and 2.34 g of NaH were added to an automatic autoclave, and the air therein was replaced with nitrogen. Then, 1550 g of propylene oxide was added in batches (15-30 batches, each batch not exceeding 100 g) at a polyaddition temperature of 115° C. and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 115° C.-125° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 550 kPa for 30 min to obtain Intermediate 1.

[0069] Preparation of Intermediate 2: 500 g of Intermediate 1 and 3.58 g of NaH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 333 g of propylene oxide was added in batches (4-10 batches, each batch not exceeding 100 g) at a polyaddition temperature of 115° C. and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 115° C.-125° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 550 kPa for 30 min to obtain Intermediate 2.

[0070] Preparation of Intermediate 3: 300 g of Intermediate 2 and 0.6 g of NaH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 260 g of propylene oxide was added in batches (3-8 batches, each batch not exceeding 100 g) at a polyaddition temperature of 115° C. and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 115° C.-125° C. for 2-3 hours, and the reaction was terminated. Then, the reaction mixture was treated under reduced pressure at the same temperature and 550 kPa for 30 min to obtain Intermediate 3.

[0071] Preparation of crude polyether polyol E: 300 g of intermediate 3 was added to an automatic autoclave, the air therein was replaced with nitrogen, N2 was charged into the autoclave to make the pressure inside the autoclave reach 0.1 MPa, and then 128 g of ethylene oxide was added in batches (in 6-10 batches) at a polyaddition temperature of 130°C and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 2-3 hours, and the reaction was terminated. Then, the reaction mixture was treated under reduced pressure at 550 kPa for 30 minutes at the same temperature to obtain crude polyether polyol E.

[0072] Refining of polyether polyol E: 500 g of crude polyether polyol E was added to an automatic autoclave, 4.3 g of cyclohexanedicarboxylic acid and 4 g of deionized water were added and stirred for 1 h at 115 ° C, and then 0.02 g-0.03 g of hydrochloric acid was added to adjust the pH value of the polyether polyol to between 5.2 and 6.5, and dehydrated to a water content of no more than 0.04%, and solid salts were removed by filtration to obtain polyether polyol E.

[0073] Example 6 Preparation of polyether polyol F

[0074] Preparation of Intermediate 1: 342 g of sucrose, 62 g of ethylene glycol and 5.61 g of NaOH were added to an automatic autoclave, and the air therein was replaced with nitrogen. Then, 2400 g of propylene oxide was added in batches (24-50 batches, each batch not exceeding 100 g) at a polyaddition temperature of 125° C. and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 125° C.-130° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 500 kPa for 30 min to obtain Intermediate 1.

[0075] Preparation of Intermediate 2: 400 g of Intermediate 1 and 1.49 g of NaOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 743 g of propylene oxide was added in batches (8-20 batches, each batch not exceeding 100 g) at a polyaddition temperature of 125° C. and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 125° C.-130° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 500 kPa for 30 minutes to obtain Intermediate 2.

[0076] Preparation of Intermediate 3: 400 g of Intermediate 2 and 0.8 g of NaOH were added to an automatic autoclave, the air therein was replaced with nitrogen, and then 300 g of propylene oxide was added in batches (3-10 batches, each batch not exceeding 100 g) at a polyaddition temperature of 125° C. and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 125° C.-130° C. for 2-3 hours, and the reaction was terminated. Then, the autoclave was treated under reduced pressure at the same temperature and 500 kPa for 30 min to obtain Intermediate 3.

[0077] Preparation of crude polyether polyol F: 400 g of intermediate 3 was added to an automatic autoclave, the air therein was replaced with nitrogen, N2 was charged into the autoclave to make the pressure in the autoclave reach 0.17 MPa, and then 57 g of ethylene oxide was added in batches (in 3-5 batches) at a polyaddition temperature of 130° C. and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130° C.-135° C. and maintained for 2-3 hours, and the reaction was terminated. Then, the autoclave was subjected to a reduced pressure treatment at the same temperature and 500 kPa for 30 minutes to obtain crude polyether polyol F.

[0078] Refining of polyether polyol F: 500 g of crude polyether polyol F was added to an automatic autoclave, 2.69 g of cyclopentanoic acid and 2 g of deionized water were added at 130°C and stirred for 1 hour, then 0.02 g to 0.03 g of sulfuric acid was added, the pH value of the polyether polyol was adjusted to between 5.8 and 7.0, dehydrated to a water content of no more than 0.04%, and solid salts were removed by filtration to obtain polyether polyol F.

[0079] Comparative Example 1 Polyether Polyol 1#

[0080] In a pressure-resistant automatic autoclave (hereinafter referred to as the automatic autoclave) equipped with a stirrer, a temperature controller, a pressure gauge, a nitrogen inlet pipe and a monomer inlet pipe, 200 g of ethylene glycol and 47.62 g of KOH are added, and the air therein is replaced with nitrogen. Then, under the conditions of a polyaddition temperature of 110°C and a maximum reaction pressure of 0.3 MPa (under standard atmospheric pressure), 32950 g of propylene oxide is added in batches (in 331-400 batches, the amount of each batch does not exceed 100 g). After the propylene oxide is completely added, the temperature of the automatic autoclave is controlled to be 110°C-120°C for 5-7 hours, and the reaction is terminated. Then, at the same temperature, the pressure is reduced for 30 minutes under 665 kPa. The air therein is replaced with nitrogen, and N2 is charged into the automatic autoclave to make the pressure in the autoclave reach 0.1 MPa. Then, under the conditions of a polyaddition temperature of 110°C and a maximum reaction pressure of 0.3 MPa (under standard atmospheric pressure), 75 g of ethylene oxide is added in batches (in 3-5 batches). After the ethylene oxide is completely added, the temperature of the automatic autoclave is controlled to be 110°C-120°C for 2-3 hours to terminate the reaction. Then, at the same temperature, the decompression treatment is carried out at 665 kPa for 30 minutes to obtain a crude polyether polyol 1#.

[0081] Refining of polyether polyol 1#: 500 g of crude polyether polyol 1# was added to an automatic autoclave, and 0.89 g of phosphoric acid was added as a refining agent at 50°C for refining process, mixed and stirred for 1 hour, the pH value of the polyether polyol was adjusted to between 5.5 and 6.5, and solid salts were filtered to obtain polyether polyol 1#.

[0082] Comparative Example 2 Preparation of Polyether Polyol 2#

[0083] In a pressure-resistant automatic autoclave (hereinafter referred to as the automatic autoclave) equipped with a stirrer, a temperature controller, a pressure gauge, a nitrogen inlet pipe and a monomer inlet pipe, 400 g of 1,2-propylene glycol and 103.6 g of KOH were added, and the air therein was replaced with nitrogen. Then, under the conditions of a polyaddition temperature of 130°C and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure), 39,000 g of propylene oxide was added in batches (in 400-600 batches, and the amount of each batch did not exceed 100 g). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 5-7 hours, and the reaction was terminated. Then, at the same temperature, the pressure was reduced for 30 minutes under 550 kPa. The air therein was replaced with nitrogen, and N2 was filled into the automatic autoclave to make the pressure in the autoclave reach 0.2 MPa. Then, under the conditions of a polyaddition temperature of 130°C and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure), 50 g of ethylene oxide was added in batches (in 3-5 batches). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 2-3 hours to terminate the reaction. Then, the reaction was treated under reduced pressure at 550 kPa for 30 minutes at the same temperature to obtain crude polyether polyol 2#.

[0084] Refining of polyether polyol 2#: 500 g of crude polyether polyol 2# was added to an automatic autoclave, 1.78 g of phosphoric acid and 6 g of deionized water were added at 70°C and stirred for 1 hour, the pH value of the polyether polyol was adjusted to between 5.5 and 6.5, dehydrated to a water content of no more than 0.04%, filtered to remove solid salts, and polyether polyol 2# was obtained.

[0085] Comparative Example 3 Preparation of Polyether Polyol 3#

[0086] In a pressure-resistant automatic autoclave (hereinafter referred to as the automatic autoclave) equipped with a stirrer, a temperature controller, a pressure gauge, a nitrogen inlet pipe and a monomer inlet pipe, 300 g of glycerol and 48.14 g of KOH are added, and the air therein is replaced with nitrogen. Then, under the conditions of a polyaddition temperature of 120°C and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure), 25,900 g of propylene oxide is added in batches (in 260-400 batches, and the amount of each batch does not exceed 100 g). After the propylene oxide is completely added, the temperature of the automatic autoclave is controlled to be 120°C-130°C for 5-7 hours, and the reaction is terminated. Then, at the same temperature, the pressure is reduced for 30 minutes under 650 kPa. The air therein is replaced with nitrogen, and N2 is charged into the automatic autoclave to make the pressure in the autoclave reach 0.15 MPa. Then, under the conditions of a polyaddition temperature of 130°C and a maximum reaction pressure of 0.4 MPa (under standard atmospheric pressure), 50 g of ethylene oxide is added in batches (in 3-5 batches). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 2-3 hours to terminate the reaction. Then, the reaction was treated under reduced pressure at 650 kPa for 30 minutes at the same temperature to obtain crude polyether polyol 3#.

[0087] Refining of polyether polyol 3#: Add 500g of crude polyether polyol 3# into an automatic autoclave, add 1.34g of phosphoric acid and 6g of deionized water at 90°C and stir for 1h, adjust the pH value of the polyether polyol to between 5.5-6.5, dehydrate to a water content of no more than 0.04%, filter and remove solid salts to obtain polyether polyol 3#.

[0088] Comparative Example 4 Preparation of Polyether Polyol 4#

[0089] In a pressure-resistant automatic autoclave (hereinafter referred to as the automatic autoclave) equipped with a stirrer, a temperature controller, a pressure gauge, a nitrogen inlet pipe and a monomer inlet pipe, 500 g of pentaerythritol and 79.8 g of KOH were added, and the air therein was replaced with nitrogen. Then, under the conditions of a polyaddition temperature of 115°C and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure), 40,900 g of propylene oxide was added in batches (in 410-500 batches, and the amount of each batch did not exceed 100 g). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 115°C-120°C for 5-7 hours, and the reaction was terminated. Then, at the same temperature, the pressure was reduced for 30 minutes under 600 kPa. The air therein was replaced with nitrogen, and N2 was filled into the automatic autoclave to make the pressure in the autoclave reach 0.1 MPa. Then, under the conditions of a polyaddition temperature of 130°C and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure), 40 g of ethylene oxide was added in batches (in 3-5 batches). After the ethylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 130°C-135°C for 2-3 hours to terminate the reaction. Then, the reaction was treated under reduced pressure at 600 kPa for 30 minutes at the same temperature to obtain crude polyether polyol 4#.

[0090] Refining of polyether polyol 4#: Add 500g of crude polyether polyol 4# into an automatic autoclave, add 1.51g of phosphoric acid and 5g of deionized water at 100°C and stir for 1h, adjust the pH value of the polyether polyol to between 5.5-6.5, dehydrate to a water content of no more than 0.04%, filter and remove solid salts to obtain polyether polyol 4#.

[0091] Comparative Example 5 Preparation of Polyether Polyol 5#

[0092] In a pressure-resistant automatic autoclave (hereinafter referred to as the automatic autoclave) equipped with a stirrer, a temperature controller, a pressure gauge, a nitrogen inlet pipe and a monomer inlet pipe, 300 g of sorbitol and 38.94 g of NaH were added, and the air therein was replaced with nitrogen. Then, under the conditions of a polyaddition temperature of 115°C and a maximum reaction pressure of 0.25 MPa (under standard atmospheric pressure), 5300 g of propylene oxide was added in batches (in 530-600 batches, the amount of each batch did not exceed 100 g). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 115°C-120°C for 5-7 hours, and the reaction was terminated. Then, at the same temperature, the pressure was reduced for 30 min under 550 kPa. The air therein was replaced with nitrogen, and N2 was filled into the automatic autoclave to make the pressure in the autoclave reach 0.1 MPa. Then, under the conditions of a polyaddition temperature of 130°C and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure), 128 g of ethylene oxide was added in batches (in 6-10 batches). After the ethylene oxide is completely added, the temperature of the automatic autoclave is controlled to be 130°C-135°C for 2-3 hours to terminate the reaction. Then, the reaction is treated under reduced pressure at 550 kPa for 30 minutes at the same temperature to obtain crude polyether polyol 5#.

[0093] Refining of polyether polyol 5#: Add 500g of crude polyether polyol 5# into an automatic autoclave, add 1.05g of phosphoric acid and 4g of deionized water at 115°C and stir for 1h, adjust the pH value of the polyether polyol to between 5.5-6.5, dehydrate to a water content of no more than 0.04%, filter and remove solid salts to obtain polyether polyol 5#.

[0094] Comparative Example 6 Preparation of Polyether Polyol 6#

[0095] In a pressure-resistant automatic autoclave (hereinafter referred to as the automatic autoclave) equipped with a stirrer, a temperature controller, a pressure gauge, a nitrogen inlet pipe and a monomer inlet pipe, 342 g of sucrose, 62 g of ethylene glycol and 32.06 g of NaOH were added, and the air therein was replaced with nitrogen. Then, under the conditions of a polyaddition temperature of 125° C. and a maximum reaction pressure of 0.35 MPa (under standard atmospheric pressure), 13720 g of propylene oxide was added in batches (140-200 batches, each batch not exceeding 100 g). After the propylene oxide was completely added, the temperature of the automatic autoclave was controlled to be 125° C.-130° C. and maintained for 5-7 hours, and the reaction was terminated. Then, at the same temperature, the pressure was reduced at 500 kPa for 30 minutes to recover the unreacted propylene oxide. The air was replaced with nitrogen, and N2 was charged into the autoclave to make the pressure in the autoclave reach 0.17MPa. Then, 57g of ethylene oxide was added in batches (3-5 batches) at a polyaddition temperature of 130°C and a maximum reaction pressure of 0.4MPa (under standard atmospheric pressure). After the ethylene oxide was completely added, the temperature of the autoclave was controlled to be 130°C-135°C for 2-3 hours, and the reaction was terminated. Then, at the same temperature, the decompression treatment was carried out at 500kPa for 30 minutes to obtain crude polyether polyol III.

[0096] Refining of polyether polyol 6#: Add 500g of crude polyether polyol 6# into an automatic autoclave, add 2.37g of phosphoric acid and 2g of deionized water at 130°C for 1h, adjust the pH value of the polyether polyol to between 5.5 and 6.5, dehydrate to a water content of no more than 0.04%, filter and remove solid salts to obtain polyether polyol 6#.

[0097] The comparison of physical properties of polyether polyols is shown in Table 1.

[0098] In the embodiments of the present invention and the comparative examples:

[0099] The test method for hydroxyl value is: GBT 12008.3-2009 Plastic polyether polyols Part 3: Determination of hydroxyl value.

[0100] Table 1 Physical properties of polyether polyols

[0101]

[0102] Note: The odor level test refers to the PV3900 [(Shanghai Volkswagen) Automobile Interior Components Odor Test] method, and the average value is taken after 5 experimenters conduct blind tests.

[0103] The odor evaluation criteria are shown in Table 2.

[0104] Table 2 Odor evaluation standards

[0105] Fraction Evaluate 1 Odorless 2 Smell is present but not obtrusive 3 There is a noticeable odor, but it is still not intrusive 4 Disturbing odor 5 Has a strong, disturbing odor 6 Has an unbearable smell

[0106] It should be noted that the above examples only list several cases, and the preparation of the low-odor high-activity polyether polyol of the present invention adopts but is not limited to the cases listed in the above examples. Using butanol, octanol, allyl alcohol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-propylene glycol, 1,4-cyclohexanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanediol, glycerol, trimethylol propane, pentaerythritol, sorbitol and other alcohols as initiators, the polyether polyols with a hydroxyl value of 8-70 mgKOH / g are all within the scope of protection of the present invention.

Claims

1. A method for preparing a polyether polyol, characterized in that: The method comprises: S1 Preparation of intermediate 1: A small molecular weight polyol compound is used as a starting polymer, contacted with a first portion of an alkali metal catalyst, and subjected to ring-opening addition polymerization of one or more epoxy compounds I at a temperature of 110 to 130° C. to obtain an intermediate 1 having a hydroxyl value of 55 to 300 mgKOH / g; S2 Preparation of intermediate 2: contacting the intermediate 1 with a second portion of an alkali metal catalyst, and performing ring-opening addition polymerization at a temperature of 110 to 130° C. to generate one or more epoxy compounds II, thereby obtaining an intermediate 2 having a hydroxyl value of 20 to 180 mgKOH / g; S3 Preparation of intermediate 3: The intermediate 2 is contacted with a third alkali metal catalyst, and subjected to ring-opening addition polymerization at a temperature of 110 to 130° C. to generate one or more epoxy compounds III, thereby obtaining an intermediate 3 having a hydroxyl value of 10 to 100 mgKOH / g; Preparation of S4 polyether polyol: The intermediate 3 is mixed with ethylene oxide, and the intermediate 3 is subjected to ring-opening polymerization of ethylene oxide at a temperature of 100 to 130° C. to perform end-capping treatment to obtain the polyether polyol.

2. The preparation method according to claim 1, characterized in that: In S1, the mass ratio of the small molecule alcohol compound, the first alkali metal catalyst, and the epoxy compound I is in the range of 1:0.005-0.17:5-10; And / or, in S2, the mass ratio of the intermediate 1, the second alkali metal catalyst, and the epoxy compound II is in the range of 1:0.003-0.1:0.5-6; And / or, in S3, the mass ratio of the intermediate 2, the third alkali metal catalyst, and the epoxy compound III is in the range of 1:0.002-0.1:0.5-6; and / or, in S4, the mass ratio of the intermediate 3 to ethylene oxide is in the range of 1:0.08 to 0.5; And / or, the epoxy compound I, epoxy compound II, and epoxy compound III are each independently selected from at least one of propylene oxide, ethylene oxide, butylene oxide, styrene oxide, cyclohexene oxide, epichlorohydrin, epibromohydrin, methyl glycidyl ether, and allyl glycidyl ether.

3. The preparation method according to claim 1 or 2, characterized in that: The small molecule polyol compound is selected from at least one of ethylene glycol, 1,2-propylene glycol, glycerol, pentaerythritol, sorbitol, mannitol, sucrose, glucose, sorbitol, dextrose, levulose, methyl glucoside and hydroxyethyl glucoside.

4. The preparation method according to claim 1, 2 or 3, characterized in that: The amount of the alkali metal catalyst is a calculated value, and the total mass of the alkali metal is 0.078% to 0.26% of the small molecule polyol.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The alkali metal catalyst is selected from at least one of NaOH, KOH and NaH.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The end-capping treatment is carried out in a nitrogen environment with a nitrogen pressure of 0.01 MPa to 0.4 MPa.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The end-capping treatment obtains an end-capped product; the method further comprises a step of refining the end-capped product; the refining step comprises sequentially performing an organic acid treatment and an inorganic acid treatment; Preferably, the organic acid is selected from at least one of cyclopentanoic acid, cyclohexanoic acid, oxalic acid, adipic acid, cyclohexanediacid, and cyclopentanoic acid; Preferably, the inorganic acid is selected from at least one of phosphoric acid, hydrochloric acid and sulfuric acid.

8. The preparation method according to claim 7, The organic acid is used to neutralize the alkali metal catalyst in the blocked product; and / or, the mass ratio of the organic acid to the end-capping product is 1:115-440; And / or, the inorganic acid is used to regulate the pH value; the pH is adjusted to 5.2-7.

0.

9. The polyether polyol obtained by the preparation method according to any one of claims 1 to 8, characterized in that: The hydroxyl value of the polyether polyol is 8 to 70 mgKOH / g.

10. Use of the polyether polyol obtained by the preparation method according to any one of claims 1 to 8 or the polyether polyol according to claim 9, characterized in that: Used in the preparation of polyurethane or as lubricant, brake fluid, resin modifier; Preferably, the polyurethane is selected from at least one of semi-rigid and soft polyurethane foams, coatings, adhesives, bed materials, waterproof materials, elastomers, sealants, and soles.

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