A preparation method of polypropylene glycol diglycidyl ether

Abstract

The present invention belongs to the technical field of organic synthesis, and specifically relates to a method for preparing polypropylene glycol diglycidyl ether. The present invention involves performing etherification ring-opening and ring-closing reactions on polypropylene glycol and epichlorohydrin. A Lewis acid catalyst is used in the etherification ring-opening reaction stage, and a phase transfer catalyst is used in the ring-closing reaction stage to catalyze the reaction, thereby ensuring that the etherification ring-opening and ring-closing reactions have high reactivity and selectivity. The resulting intermediate product, chlorohydrin ether, undergoes a ring-closing reaction with the addition of a base in the presence of a phase transfer catalyst, thereby shortening the reaction time. Furthermore, the ring-closing reaction is performed under vacuum conditions, which promotes decompression and dehydration, thereby promoting the forward reaction, allowing the intermediate chlorohydrin ether to react as much as possible. Furthermore, the reaction can be relatively complete without requiring a very high temperature, effectively reducing hydrolyzable chlorine, and ultimately reducing alkali consumption during the preparation process and the color of the finished polypropylene glycol diglycidyl ether.

Description

Technical Field

[0001] The invention belongs to the technical field of organic synthesis, and particularly relates to a method for preparing polypropylene glycol diglycidyl ether. Background Art

[0002] Polypropylene glycol diglycidyl ether is a bifunctional active diluent widely used in the coatings industry and synthetic chemical industry. It has the characteristics of good flexibility, low viscosity, low volatility, low odor and low toxicity. Polypropylene glycol diglycidyl ether can be used as a diluent for epoxy resin to reduce the viscosity of the epoxy system. It can also participate in the curing reaction of epoxy resin, reduce the viscosity of the curing system, increase fluidity, and extend the service life of the epoxy resin, making it easy to use in large-scale construction. While improving operability, it does not affect the basic properties of the cured product and is convenient for use in casting, pouring, bonding, sealing, impregnation and other aspects.

[0003] Currently, the method commonly used in the literature for synthesizing polypropylene glycol diglycidyl ether includes a one-step solid alkali synthesis method. This method is simple and convenient, but the reaction is difficult to control, the product has high uncertainty, and the resulting product has high color. For example, Gao Xiaolian's 2001 paper "Study on the Synthesis of Polypropylene Glycidyl Ether" used a one-step solid alkali method. However, this method suffers from a serious excess of solid alkali and epichlorohydrin, making the preparation method complex and costly.

[0004] In addition, there is a two-step synthesis method that is simple to operate and easy to control temperature. For example, Yu Longying et al. reported a two-step method for synthesizing polypropylene glycol diglycidyl ether in "Research on the Two-Step Synthesis of High-Epoxy Value and Low-Viscosity Polypropylene Glycidyl Ether": Using polypropylene glycol as the raw material, under the catalysis of HF, it is added to epichlorohydrin to open the ring to obtain an intermediate with an epichlorohydrin ether structure. The intermediate is then reacted with a 50wt.% NaOH solution to close the ring and remove hydrogen chloride to obtain the product. The main reaction equation is as follows:

[0005] Etherification:

[0006]

[0007] Cyclization:

[0008]

[0009] But in the synthetic method of the polypropylene glycol diglycidyl ether, when the closed-loop reaction stage temperature is too high, reaction is more violent, makes finished product colority not good, also can produce more by-products, cause the epoxide value of finished product to reduce, this in industrial production, also can promote industrial waste disposal cost;And lower closed-loop temperature is unfavorable for the epoxidation of chlorohydrin ether.In the closed-loop stage, alkali is the reaction reagent that removes hydrogen chloride closed loop to form glycidyl ether, if consumption is not enough, then makes closed-loop reaction not complete, consumption is too much then can cause reaction violent, by-product increases, productive rate reduces, will increase raw material cost in industrial production.It can be seen from this that in the preparation of current polypropylene glycol diglycidyl ether, there are problems such as product colority is high, alkali consumption is high. Summary of the Invention

[0010] In view of this, the object of the present invention is to provide a method for preparing polypropylene glycol diglycidyl ether, thereby reducing the alkali consumption in the preparation process and the chromaticity of the product.

[0011] In order to achieve the above object, the present invention provides the following technical solutions:

[0012] The present invention provides a method for preparing polypropylene glycol diglycidyl ether, comprising the following steps:

[0013] Mixing polypropylene glycol, epichlorohydrin, a Lewis acid catalyst and a first solvent to carry out an etherification ring-opening reaction to obtain an intermediate chlorohydrin ether;

[0014] The intermediate chlorohydrin, a phase transfer catalyst, an alkaline solution and a second solvent are mixed, and a ring-closing reaction is carried out under vacuum conditions to obtain polypropylene glycol diglycidyl ether;

[0015] The vacuum degree of the ring-closing reaction is 90-94 kPa; the temperature of the ring-closing reaction is 45-60°C.

[0016] Preferably, the Lewis acid catalyst comprises one or more of tin tetrachloride, zinc perchlorate, boron trifluoride etherate, ferric chloride and aluminum chloride; the mass of the Lewis acid catalyst is 0.5-2% of the mass of the polypropylene glycol.

[0017] Preferably, the molar ratio of the polypropylene glycol to epichlorohydrin is 1:(2.0-2.5).

[0018] Preferably, the temperature of the etherification ring-opening reaction is 45-60° C., and the insulation time is 1-4 hours.

[0019] Preferably, the phase transfer catalyst is polyethylene glycol; the mass of the phase transfer catalyst is 0.5-2% of the mass of polypropylene glycol.

[0020] Preferably, the insulation time of the ring-closure reaction is 2 to 3 hours.

[0021] Preferably, the mass percentage of alkali in the alkaline solution is 30-50%; the alkali is sodium hydroxide and / or potassium hydroxide.

[0022] Preferably, the molar ratio of the base to polypropylene glycol is (1.9-2.4):1.

[0023] Preferably, the first solvent and the second solvent are toluene.

[0024] Preferably, the polyethylene glycol is PEG-200 and / or PEG-400.

[0025] The invention provides a preparation method of polypropylene glycol diglycidyl ether. The method comprises the following steps: mixing polypropylene glycol, epichlorohydrin, a Lewis acid catalyst and a first solvent, performing an etherification ring-opening reaction to obtain an intermediate chlorohydrin ether; mixing the intermediate chlorohydrin, a phase transfer catalyst, an alkaline solution and a second solvent, performing a ring-closing reaction under vacuum conditions to obtain polypropylene glycol diglycidyl ether; the vacuum degree of the ring-closing reaction is 90-94 kPa; and the temperature of the ring-closing reaction is 45-60°C. The invention carries out etherification ring-opening and ring-closing reactions on polypropylene glycol and epichlorohydrin. A Lewis acid catalyst is used in the etherification ring-opening reaction stage, and a phase transfer catalyst is used to catalyze the reaction in the ring-closing reaction stage, thereby ensuring that the etherification ring-opening and ring-closing reactions have high reactivity and selectivity. In the presence of the phase transfer catalyst, an alkali is added to the obtained intermediate chlorohydrin ether for ring-closing reaction, thereby shortening the reaction time. Moreover, the ring-closing reaction is carried out under vacuum conditions, which can promote decompression dehydration, thereby promoting the forward reaction, allowing the intermediate chlorohydrin ether to react as much as possible, reducing the amount of alkali in the raw materials, namely reducing alkali consumption, and saving raw material costs. Moreover, due to the reduced pressure, the reaction can be relatively complete at a lower temperature, thereby protecting the chromaticity of the product, effectively reducing hydrolyzable chlorine, and ultimately reducing the alkali consumption in the preparation process and the chromaticity of the finished polypropylene glycol diglycidyl ether. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a Fourier transform infrared spectrum of polypropylene glycol diglycidyl ether prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0027] The present invention provides a method for preparing polypropylene glycol diglycidyl ether, comprising the following steps:

[0028] Mixing polypropylene glycol, epichlorohydrin, a Lewis acid catalyst and a first solvent to carry out an etherification ring-opening reaction to obtain an intermediate chlorohydrin ether;

[0029] The intermediate chlorohydrin, a phase transfer catalyst, an alkaline solution and a second solvent are mixed, and a ring-closing reaction is carried out under vacuum conditions to obtain polypropylene glycol diglycidyl ether;

[0030] The vacuum degree of the ring-closing reaction is 90-94 kPa; the temperature of the ring-closing reaction is 45-60°C.

[0031] Unless otherwise specified, the present invention has no special requirements on the sources of the raw materials used, and commercially available products known to those skilled in the art can be used.

[0032] The invention mixes polypropylene glycol, epichlorohydrin, a Lewis acid catalyst and a first solvent, and performs an etherification ring-opening reaction to obtain an intermediate chlorohydrin ether.

[0033] In the present invention, the molar ratio of the polypropylene glycol to epichlorohydrin is preferably 1:(2.0-2.5), more preferably 1:(2.1-2.4); the molecular weight of the polypropylene glycol is preferably 400.

[0034] In the present invention, the Lewis acid catalyst preferably includes one or more of tin tetrachloride, zinc perchlorate, boron trifluoride ethyl ether complex, ferric chloride and aluminum trichloride, and more preferably one or more of tin tetrachloride, zinc perchlorate and boron trifluoride ethyl ether complex. When the Lewis acid catalyst is one of the above-mentioned types, the present invention has no special limitation on the ratio of different types of Lewis acid catalysts, and any ratio can be used. The mass of the Lewis acid catalyst is preferably 0.5-2% of the mass of the polypropylene glycol, and more preferably 1-1.5%.

[0035] In the present invention, the first solvent is preferably toluene; the mass ratio of the first solvent to polypropylene glycol is preferably (0.05-0.1):1, more preferably 0.07:1.

[0036] In the present invention, the polypropylene glycol, epichlorohydrin, a Lewis acid catalyst and a first solvent are mixed, preferably the polypropylene glycol, the first solvent and the Lewis acid catalyst are mixed and heated, and then epichlorohydrin is added dropwise at the same temperature; the heating temperature is preferably 38 to 42°C, more preferably 40°C; the dropping rate is preferably 20 to 60 drops / min, more preferably 30 to 50 drops / min; the dropping time is preferably 1 to 5 hours, more preferably 3 to 4 hours; after the dropwise addition is completed, the present invention preferably heats the temperature of the mixed system to the temperature of the etherification ring-opening reaction; the heating rate is preferably 1 to 3°C / min, more preferably 2°C / min.

[0037] In the present invention, the temperature of the etherification ring-opening reaction is preferably 43-47°C, more preferably 45°C, and the holding time is 1-4 hours, more preferably 2-3 hours; the etherification ring-opening reaction is preferably carried out under stirring; the stirring rate is preferably 250-350 rpm, more preferably 250-300 rpm.

[0038] The Lewis acid catalyst used in the present invention has good selectivity, can reduce the progress of side reactions, and further reduce the generation of by-products, so as to achieve a higher yield.

[0039] After obtaining the intermediate chlorohydrin ether, the present invention mixes the intermediate chlorohydrin, a phase transfer catalyst, an alkaline solution and a second solvent, and performs a ring-closing reaction under vacuum conditions.

[0040] In the present invention, the phase transfer catalyst is preferably polyethylene glycol; the polyethylene glycol is preferably PEG-200 and / or PEG-400, more preferably PEG-400. When the polyethylene glycol is PEG-200 or PEG-400, the present invention does not specifically limit the ratio of PEG-200 to PEG-400; any ratio may be used. In the present invention, the mass of the phase transfer catalyst is preferably 0.5-2% of the mass of the polypropylene glycol, more preferably 0.7-1.5%.

[0041] In the present invention, the mass percentage of the alkali in the alkaline solution is preferably 30-50%, more preferably 40-50%; the alkali is preferably sodium hydroxide and / or potassium hydroxide, more preferably sodium hydroxide. When the alkali is sodium hydroxide and potassium hydroxide, the present invention does not specifically limit the ratio of sodium hydroxide and potassium hydroxide, and any ratio can be used. In the present invention, the molar ratio of the alkali to the polypropylene glycol is preferably (1.9-2.4):1, more preferably (2-2.25):1.

[0042] Alkali solution is added under reduced pressure to remove moisture from the reaction system, promote the forward reaction, and reduce the amount of alkali used in the raw materials, that is, reduce alkali consumption and save raw material costs. In addition, due to the reduced pressure, the reaction can be more complete at a lower temperature, thereby protecting the color of the product.

[0043] In the present invention, the second solvent is preferably toluene; the mass ratio of the second solvent to the phase transfer catalyst is preferably (10-30):1, more preferably 20:1.

[0044] In the present invention, the intermediate chlorohydrin, the phase transfer catalyst, the alkaline solution and the second solvent are preferably mixed as follows: after the intermediate chlorohydrin is cooled, the phase transfer catalyst and the second solvent are added, and the alkaline solution is added dropwise; the temperature of the intermediate chlorohydrin after cooling is preferably 25 to 35° C., more preferably 30° C.; the dropping rate is preferably 30 to 60 drops / min, more preferably 40 to 50 drops / min; the dropping time is preferably 1.5 to 3 h, more preferably 2 h.

[0045] In the present invention, the temperature of the ring-closure reaction is 45 to 60° C., preferably 50 to 55° C.; the holding time of the ring-closure reaction is preferably 2 to 3 hours, more preferably 2 to 2.5 hours; the vacuum degree of the ring-closure reaction is 90 to 94 kPa, preferably 92 kPa; and the heating rate from the temperature of the intermediate chlorohydrin after cooling to the ring-closure reaction temperature is preferably 1 to 3° C. / min, more preferably 2° C. / min.

[0046] The phase transfer catalyst in the present invention can improve the reaction activity and has a better ring-closing effect.

[0047] The present invention carries out etherification ring-opening and ring-closing reactions on polypropylene glycol and epichlorohydrin, adopts a Lewis acid catalyst in the etherification ring-opening reaction stage, and adopts a phase transfer catalyst in the ring-closing reaction stage to catalyze the reaction, thereby ensuring that the etherification ring-opening and ring-closing reactions have high reaction activity and selectivity.

[0048] The intermediate chlorohydrin ether is subjected to a ring-closure reaction by adding alkali in the presence of a phase transfer catalyst, thereby shortening the reaction time. Furthermore, the ring-closure reaction is carried out under vacuum conditions, which can promote decompression and dehydration, thereby promoting the forward reaction, allowing the intermediate chlorohydrin ether to react as much as possible, reducing the amount of alkali in the raw materials, i.e., reducing alkali consumption and saving raw material costs. Furthermore, due to the reduced pressure, the reaction can be relatively complete at a lower temperature, thereby protecting the color of the product and effectively reducing hydrolyzable chlorine. Ultimately, this reduces alkali consumption during the preparation process and the color of the finished polypropylene glycol diglycidyl ether.

[0049] After the ring-closure reaction, the product obtained from the ring-closure reaction is preferably post-treated to obtain polypropylene glycol diglycidyl ether. In the present invention, the post-treatment preferably includes: a first water wash, neutralization, a second water wash, vacuum dehydration to remove solvents, and filtration.

[0050] In the present invention, the reagent used for the first water washing and the second water washing is preferably deionized water; the temperature of the deionized water is preferably 70-90°C, more preferably 80°C; the first water washing and the second water washing are preferably carried out under stirring; the stirring rate is preferably 250-350rpm, more preferably 300rpm; the stirring time is preferably 12-18min, more preferably 15min; the present invention preferably allows the system obtained by the first water washing and the second water washing to stand and then remove the lower layer of water to obtain an organic phase; the standing time is preferably 8-12min, more preferably 10min.

[0051] In the present invention, the neutralization is preferably performed by mixing and stirring the organic phase after the first water washing with deionized water, adding a weak acid salt to adjust the pH value to 6-7, and then standing and removing the lower layer of water to obtain a neutralized organic phase; the weak acid salt is preferably sodium dihydrogen phosphate; the weak acid salt is added to adjust the pH value to 7; the stirring rate is preferably 250-350 rpm, more preferably 300 rpm; the stirring time is preferably 12-18 min, more preferably 15 min; the standing time is preferably 8-12 min, more preferably 10 min.

[0052] In the present invention, the temperature of the vacuum dehydration and desolvation is preferably 100-130°C, more preferably 120°C; the vacuum degree of the vacuum dehydration and desolvation is preferably 18-22 Torr, more preferably 20 Torr; the present invention preferably vacuum dehydration and desolvation to a water content of <1000ppm and a solvent content of <1000ppm.

[0053] The present invention has no particular limitation on filtration, and any filtration method known in the art may be used.

[0054] The invention adds the solvent in three stages, namely before ring opening, before ring closing and before post-treatment, which can not only protect the reaction from proceeding mildly and reduce the chromaticity of the product, but also control the concentration of the solution in each stage and make the reaction process proceed more thoroughly.

[0055] In the present invention, the alkali consumption of the preparation method is preferably 110-120 g / mol, more preferably 114 g / mol; the chromaticity of the polypropylene glycol diglycidyl ether is preferably 5-15 APHA, more preferably 5-10 AHPA.

[0056] The technical solutions of the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention, but they should not be understood as limiting the scope of protection of the present invention.

[0057] Example 1

[0058] In 1L reaction flask, add 276g polypropylene glycol (molecular weight is 400), 20g toluene, 2g boron trifluoride ether complex and 2g tin tetrachloride, stir with 300rpm, after being heated to 40 ℃, maintain this reaction temperature, in 3h, drip epichlorohydrin 159g at the speed of 50 drops / min, after being added dropwise to complete, be warming up to 45 ℃ with 2 ℃ / min heating rates and continue to stir, carry out etherification ring-opening reaction 4h, obtain intermediate epichlorohydrin ether; Gained intermediate epichlorohydrin ether is cooled to 30 ℃, add 40g toluene and 4g phase-transfer catalyst PEG-400, in 2h, drip 124g50wt.%NaOH solution with the speed of 50 drops / min, after finishing dropwise, in 2h, be warming up to 55 ℃ with 2 ℃ / min heating rates, being decompressed to vacuum is 92kPa, carry out ring-closure reaction 2h; Afterwards, add 200g Add 80°C hot water, stir at 300 rpm for 15 minutes, let it stand for 10 minutes, remove the lower layer of brine, add 100g of 80°C deionized water, stir at 300 rpm for 15 minutes, add 2g of sodium dihydrogen phosphate to neutralize to pH 7, let it stand for 10 minutes, remove the lower layer of water, add 100g of 80°C deionized water, stir at 300 rpm for 15 minutes, let it stand for 10 minutes, remove the lower layer of water, dehydrate and desolvate under vacuum at 20 Torr and 120°C until the water and solvent content is <1000ppm, and filter to obtain polypropylene glycol diglycidyl ether product.

[0059] Example 2

[0060] 276g of polypropylene glycol (molecular weight of 400), 20g of toluene, 2g of tin tetrachloride and 2g of zinc perchlorate were added to a 1L reaction flask, stirred at 250rpm, heated to 40°C, maintained the reaction temperature, and 134g of epichlorohydrin was added dropwise at a rate of 50 drops / min within 5h. After the addition was complete, the temperature was raised to 45°C at a heating rate of 1°C / min and continued to stir. The etherification ring-opening reaction was carried out for 4h to obtain the intermediate epichlorohydrin ether; the obtained intermediate epichlorohydrin ether was cooled to 30°C, 40g of toluene and 2g of phase transfer catalyst PEG-400 were added dropwise, and 124g of After the addition of 50wt.% NaOH solution, the temperature was raised to 55°C at a heating rate of 1°C / min within 2h, the pressure was reduced to a vacuum degree of 92kPa, and a ring-closure reaction was carried out for 2.5h; then, 200g of 80°C hot water was added, stirred at 250rpm for 15min, and the lower brine layer was separated after standing for 10min. Then, 100g of 80°C deionized water was added, stirred at 250rpm for 15min, and 2g of sodium dihydrogen phosphate was added to neutralize to a pH value of 7. After standing for 10min, the lower water layer was separated, and 100g of 80°C deionized water was added, stirred at 250rpm for 15min, and the lower water layer was separated. After standing for 10min, the lower water layer was separated, and the mixture was dehydrated and desolvated under vacuum at 20Torr and 120°C until the water and solvent content was <1000ppm, and then filtered to obtain the polypropylene glycol diglycidyl ether product.

[0061] Example 3

[0062] In 1L reaction flask, add 276g polypropylene glycol (molecular weight is 400), 20g toluene, 2g tin tetrachloride and 2g boron trifluoride diethyl ether complex, stir with 300rpm, after being heated to 40 ℃, maintain temperature of reaction, in 5h, with the speed of 40 drops / min, drip epichlorohydrin 134g, after being added dropwise to complete, be warming up to 45 ℃ with 1 ℃ / min heating rate and continue to stir, carry out etherification ring-opening reaction 3h, obtain intermediate epichlorohydrin ether; Gained intermediate epichlorohydrin ether is cooled to 30 ℃, add 40g toluene and 1.5g phase-transfer catalyst PEG-400, in 2h, with the speed of 40 drops / min, drip 109g 50wt.%NaOH solution, after dropping and finishing, in 2h, be warming up to 55 ℃ with 1 ℃ / min heating rate, being decompressed to vacuum is 92kPa, carry out ring-closure reaction 3h; Afterwards, add 200g Add 80°C hot water, stir at 300 rpm for 15 minutes, let it stand for 10 minutes, remove the lower layer of brine, add 100g of 80°C deionized water, stir at 300 rpm for 15 minutes, add 2g of sodium dihydrogen phosphate to neutralize to pH 7, let it stand for 10 minutes, remove the lower layer of water, add 100g of 80°C deionized water, stir at 300 rpm for 15 minutes, let it stand for 10 minutes, remove the lower layer of water, dehydrate and desolvate under vacuum at 20 Torr and 120°C until the water and solvent content is <1000ppm, and filter to obtain polypropylene glycol diglycidyl ether product.

[0063] Comparative Example 1

[0064] In a 1L reaction flask, 276g polypropylene glycol (molecular weight is 400), 20g toluene, 2g boron trifluoride ether complex and 2g tin tetrachloride were added, stirred at 300rpm, heated to 40 ℃, maintained this reaction temperature, 134g of epichlorohydrin was added dropwise at a speed of 50 drops / min in 5h, after the dropwise addition was completed, was warming up to 45 ℃ with a 2 ℃ / min heating rate and continued to stir, carried out etherification ring-opening reaction for 4h, and obtained the intermediate epichlorohydrin ether; the gained intermediate epichlorohydrin ether was cooled to 30 ℃, 40g toluene and 1.5g phase-transfer catalyst PEG-400 were added dropwise, 139g 50wt.% NaOH solution was added dropwise at a speed of 50 drops / min in 2h, after the dropwise addition was completed, was warming up to 40 ℃ with a 2 ℃ / min heating rate and carried out ring-closure reaction for 2h in 2h; Afterwards, 200g Add 80°C hot water, stir at 300 rpm for 15 minutes, let it stand for 10 minutes, remove the lower layer of brine, add 100g of 80°C deionized water, stir at 300 rpm for 15 minutes, add 2.5g of sodium dihydrogen phosphate to neutralize to pH 7, let it stand for 10 minutes, remove the lower layer of water, add 100g of 80°C deionized water, stir at 300 rpm for 15 minutes, let it stand for 10 minutes, remove the lower layer of water, dehydrate and desolventize under vacuum at 20 Torr and 120°C until the water and solvent content is <1000ppm, and filter to obtain polypropylene glycol diglycidyl ether product.

[0065] Performance Testing

[0066] (1) The polypropylene glycol diglycidyl ether product prepared in Example 1 was subjected to Fourier transform infrared spectroscopy test, and the results were as follows: Figure 1 shown.

[0067] Depend on Figure 1 It can be seen that the polypropylene glycol diglycidyl ether product prepared by the present invention is indeed polypropylene glycol diglycidyl ether after testing.

[0068] (2) The raw material consumption, the quality of the obtained polypropylene glycol diglycidyl ether product and the high brine in the preparation process of Examples 1 to 3 and Comparative Example 1 were tested. The results are shown in Table 1.

[0069] Table 1 Product quality of polypropylene glycol diglycidyl ether obtained in Examples 1 to 3 and Comparative Example 1

[0070]

[0071] It can be seen from Table 1 that, compared with the comparative example, the polypropylene glycol diglycidyl ether prepared in the present invention has lower chroma, epoxy equivalent, hydrolysis rate, residual alkali and alkali consumption.

[0072] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention rather than all the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A method for preparing polypropylene glycol diglycidyl ether, characterized in that: The following steps are involved: In a 1L reaction flask, 276g of polypropylene glycol (molecular weight 400), 20g of toluene, 2g of tin tetrachloride, and 2g of zinc perchlorate were added, stirred at 250rpm, heated to 40°C, and the reaction temperature was maintained. 134g of epichlorohydrin was added dropwise at a rate of 50 drops / min over 5h. After the addition was complete, the temperature was raised to 45°C at a rate of 1°C / min and stirring was continued. The etherification ring-opening reaction was carried out for 4h to obtain the intermediate epichlorohydrin ether; The obtained intermediate epichlorohydrin ether was cooled to 30° C., 40 g of toluene and 2 g of phase transfer catalyst PEG-400 were added, and 124 g of 50 wt.% NaOH solution was added dropwise at a rate of 50 drops / min over 2 h. After the addition was completed, the temperature was raised to 55° C. at a rate of 1° C. / min over 2 h, the pressure was reduced to a vacuum degree of 92 kPa, and a ring-closure reaction was carried out for 2.5 h. Subsequently, 200 g of 80° C. hot water was added, the mixture was stirred at 250 rpm for 15 min, the lower brine was removed after standing for 10 min, 100 g of 80° C. deionized water was added, the mixture was stirred at 250 rpm for 15 min, 2 g of sodium dihydrogen phosphate was added to neutralize the mixture to a pH of 7, the mixture was allowed to stand for 10 min, the lower water layer was removed, and 100 g of Add 80℃ deionized water, stir at 250rpm for 15min, let it stand for 10min, remove the lower layer of water, dehydrate and remove the solvent at 20Torr and 120℃ in vacuum until the water and solvent content is less than 1000ppm, and filter to obtain polypropylene glycol diglycidyl ether product.

Images