A kind of preparation method of tert-butyl perbenzoate

Abstract

This invention provides a method for preparing tert-butyl peroxide, relating to the field of tert-butyl peroxide synthesis technology. The preparation method includes the following steps: S1: pumping liquid alkali and water into a reaction vessel; S2: adding tert-butyl hydrogen peroxide to the reaction vessel to carry out a salt formation reaction; S3: after the salt formation reaction is completed, adding benzoyl chloride and a catalyst to carry out a condensation reaction to obtain crude tert-butyl peroxide; S4: washing the crude tert-butyl peroxide with alkali and water, and then adding a stabilizer and a co-solvent to obtain the finished product. The preparation method can improve the yield and stability of tert-butyl peroxide.

Description

Technical Field

[0001] The invention relates to the technical field of tert-butyl perbenzoate synthesis, and in particular to a method for preparing tert-butyl perbenzoate. Background Art

[0002] Tert-Butyl peroxybenzoate, abbreviated as TBPB, is mainly prepared from benzoyl chloride, tert-butyl hydroperoxide and sodium hydroxide. The prior art process for preparing tert-butyl peroxybenzoate has the problems of low yield and conversion rate of tert-butyl peroxybenzoate, and is not easy to store and transport. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art, provide a method for preparing tert-butyl perbenzoate, and improve the yield, conversion rate and stability of the preparation of tert-butyl perbenzoate in the prior art.

[0004] In order to achieve the above purpose and other purposes, the present invention is implemented by including the following technical scheme: The present invention first provides a preparation method of tert-butyl perbenzoate, and the preparation method comprises the following steps:

[0005] S1: pumping liquid alkali and water into the reactor;

[0006] S2: adding tert-butyl hydroperoxide (TBHP) into the reactor to carry out salt-forming reaction;

[0007] S3: After the salt-forming reaction is completed, benzoyl chloride and a catalyst are added to carry out a condensation reaction to obtain a crude product of tert-butyl perbenzoate;

[0008] S4: washing the crude product of tert-butyl perbenzoate with alkali and water, and then adding a stabilizer and a co-solvent to obtain a finished product;

[0009] The catalyst preparation process comprises:

[0010] (1) dissolving 20 to 30 parts of N-allyl-N-methylaniline and 15 to 20 parts of 3-chloropropanol in 50 to 60 parts of ethanol, reacting at 70 to 80° C. for 20 to 24 hours under nitrogen protection, evaporating the solvent, washing and vacuum drying to obtain a first product;

[0011] (2) dissolving 30 to 40 parts of the first product and 15 to 25 parts of 1-(prop-2-en-1-yl)piperidin-4-amine in 70 to 80 parts of ethyl acetate and 10 to 20 parts of methanol, adding 0.2 to 0.3 parts of azobisisobutyronitrile, stirring, reacting at 60 to 70° C. under nitrogen protection for 10 to 12 hours, filtering, washing, and vacuum drying to obtain a second product;

[0012] (3) 30 to 40 parts of the second product, 50 to 60 parts of an alkaline solution and 12 to 20 parts of epichlorohydrin are reacted at 50 to 60° C. for 6 to 8 hours under nitrogen protection, and the reaction is filtered, washed and dried to obtain the catalyst.

[0013] The invention has the beneficial effects that: a quaternary ammonium salt polymer with a piperidine ring can be obtained by reacting N-allyl-N-methylaniline, 3-chloropropanol and 1-(propyl-2-ene-1-yl) piperidine-4-amine, and epichlorohydrin is used to crosslink the hydroxyl and amino groups on the quaternary ammonium salt polymer to form a quaternary ammonium salt phase-transfer catalyst with a certain network structure, the catalyst contains piperidine, which can form an adduct with water, thereby reducing the contact of water molecules with benzoyl chloride, and the catalyst has a certain network structure and can associate with water molecules by means of physical winding, thereby reducing the contact of water molecules with benzoyl chloride, so as to reduce the problem of hydrolysis of benzoyl chloride, and improve the yield and conversion rate of the product. The positive ammonium ion in the quaternary ammonium salt phase-transfer catalyst can form an ion pair with the negative ion in tert-butyl sodium peroxide, thereby improving the efficiency of the reaction, and the benzene ring contained in the catalyst can form a π-π stacking effect with the benzene ring in the reaction system, thereby helping to stabilize the transition state and reduce the activation energy of the reaction.

[0014] The reaction formula of the salt-forming reaction is:

[0015]

[0016] The reaction formula of the condensation reaction is:

[0017]

[0018] In some embodiments, the amount of the catalyst is 0.2-0.3% of the amount of the benzoyl chloride.

[0019] In some embodiments, the stabilizer includes a first stabilizer and a second stabilizer, the first stabilizer is a tert-butylphenol stabilizer, the second stabilizer is an amine stabilizer, and the weight ratio of the first stabilizer to the second stabilizer is 1:(1.5-2).

[0020] In some embodiments, the preparation of the first stabilizer comprises: reacting 12 to 15 parts of acrylic acid, 20 to 30 parts of ethylene glycol methyl ether methacrylate, 30 to 40 parts of 2,6-di-tert-butyl-4-vinylphenol and 0.3 to 0.5 parts of potassium persulfate at 70 to 80° C. for 4 to 5 hours under nitrogen protection, and purifying and drying to obtain the first stabilizer.

[0021] In some embodiments, the preparation process of the second stabilizer comprises:

[0022] S11: reacting 10-20 parts of maleic anhydride, 15-35 parts of 4-acetoxystyrene and 0.2-0.3 parts of benzoyl peroxide at 70-80° C. for 4-6 hours under nitrogen protection, followed by cooling, filtering, washing and drying to obtain a polymer;

[0023] S12: 30-40 parts of the polymer and 15-20 parts of tetraethylenepentamine are reacted at 140-150° C. for 4-5 hours under nitrogen protection, and then cooled, filtered, washed and dried to obtain the second stabilizer.

[0024] The beneficial effects are as follows: the stabilizer is a long-chain molecule with certain steric hindrance, which can enhance the dispersibility of tert-butyl perbenzoate; the stabilizer has certain ether bonds, carboxyl groups, hydroxyl groups and other active groups, which can better disperse tert-butyl perbenzoate.

[0025] The combination of two stabilizers can synergistically promote the stability of tert-butyl perbenzoate. The first stabilizer is a tert-butylphenol stabilizer that can block free radical chain reactions. The first stabilizer also contains benzene rings and tert-butyl groups, which can enhance compatibility with tert-butyl perbenzoate. The second stabilizer is an amine stabilizer with a certain alkalinity, which can make the product system in a more stable pH environment to a certain extent. Amine stabilizers also help reduce the generation of free radicals. The second stabilizer also contains ester bonds, benzene rings, etc., and has good compatibility with the first stabilizer. The addition of stabilizers can facilitate the transportation and storage of tert-butyl perbenzoate.

[0026] In some embodiments, the co-solvent is isooctane, and the amount of the isooctane added is 1 to 1.5 times the amount of the stabilizer added.

[0027] In some embodiments, in step S1, the liquid caustic soda is sodium hydroxide, and the concentration of the liquid caustic soda is 30-40%.

[0028] In some embodiments, in step S2, the concentration of tert-butyl hydroperoxide is 65-70%, the temperature of the salt-forming reaction is 30-35° C., and the time of the salt-forming reaction is 25-30 minutes.

[0029] In some embodiments, in step S3, the temperature of the condensation reaction is 28-32° C., and the time of the condensation reaction is 60-80 minutes. DETAILED DESCRIPTION

[0030] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0031] In the following examples, N-allyl-N-methylaniline was purchased from Monomer Polymer Dayak Laboratory, 3-chloropropanol was purchased from Wuhan Kanos Technology Co., Ltd., 1-(prop-2-en-1-yl)piperidin-4-amine was purchased from Nantong Hanfang Biotechnology Co., Ltd., epichlorohydrin was purchased from Shandong Jinyueyuan New Materials Co., Ltd., acrylic acid was purchased from Jiangsu Jurong Chemical Co., Ltd., ethylene glycol methyl ether methacrylate was purchased from Sigma-Aldrich (Shanghai) Trading Co., Ltd., 2,6-di-tert-butyl-4-vinylphenol was purchased from Shanghai Bid Pharmaceutical Technology Co., Ltd., maleic anhydride was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., and tetraethylenepentamine and 4-acetoxystyrene were purchased from Shanghai McLean Biochemical Technology Co., Ltd.

[0032] Example 1

[0033] 1) Alkali preparation: a certain amount of water and 30% liquid alkali are delivered into the reactor through a delivery pipeline, stirring is started, and the refrigerated brine is turned on to cool down to 20°C.

[0034] 2) Salt-forming reaction: The temperature in the reactor is controlled at about 20° C. and a certain amount of 70% tert-butyl hydroperoxide is added dropwise, and the temperature is controlled below 35° C. After the addition of tert-butyl hydroperoxide, the reaction is continued for 25 to 30 minutes.

[0035] 3) Condensation reaction: When the temperature in the reactor drops to about 20°C, a quantitative amount of 99% benzoyl chloride and a catalyst are added dropwise, with the catalyst amount being 0.2% of the weight of the benzoyl chloride. The dropping speed and the heating rate are controlled, and the reaction temperature is controlled at 28-32°C. After the benzoyl chloride is added dropwise, the reaction is kept warm for 1 hour, and the temperature is controlled between 28-30°C.

[0036] The preparation of the catalyst comprises: dissolving 20 parts of N-allyl-N-methylaniline and 15 parts of 3-chloropropanol in 50 parts of ethanol, reacting at 70° C. for 24 hours under nitrogen protection, evaporating the solvent, washing and vacuum drying to obtain a first product;

[0037] 30 parts of the first product and 15 parts of 1-(prop-2-en-1-yl)piperidin-4-amine were dissolved in 70 parts of ethyl acetate and 10 parts of methanol, and 0.2 parts of initiator azobisisobutyronitrile was added, stirred, reacted at 60° C. in a nitrogen atmosphere for 12 hours, and filtered, washed, and vacuum dried to obtain a second product;

[0038] 30 parts of the second product, 50 parts of 15% sodium hydroxide solution and 12 parts of epichlorohydrin were reacted at 50° C. for 6 hours under nitrogen protection. After the reaction, the catalyst was filtered, washed and dried to obtain the catalyst.

[0039] 4) Static stratification: Sampling and analysis: When the chloride ion content is less than 0.01%, it is qualified, and stirring is stopped, and static stratification is performed. The lower mother liquor is discharged into the acidification kettle for treatment, and the upper product is washed with alkali.

[0040] 5) Alkali washing: add a certain amount of 3% liquid alkali, start stirring and carry out the first alkali washing for about 10 minutes, let it stand and separate, and the lower layer of alkali washing wastewater is discharged into the alkali washing wastewater kettle for treatment; repeat the above alkali washing operation, let it stand and separate, and the lower layer of alkali washing wastewater is also discharged into the alkali washing wastewater kettle for treatment. The residual tert-butyl hydroperoxide content in the product is tested to be qualified when it is less than 0.1%.

[0041] 6) Washing: Add a certain amount of soft water, start stirring and wash for about 10 minutes, let stand and separate, and use the lower layer of washing wastewater as alkali preparation water; repeat the above washing operation, let stand and separate, and the lower layer of washing wastewater is also discharged into the washing wastewater as alkali preparation water. The product is qualified when the pH value is 7.

[0042] 7) Frozen packaging: Lower the kettle temperature to -10℃ before packaging.

[0043] 8) Storage: The product should be stored below 20°C.

[0044] Example 2

[0045] 1) Alkali preparation: a certain amount of water and 30% liquid alkali are delivered into the reactor through a delivery pipeline, stirring is started, and the refrigerated brine is turned on to cool down to 20°C.

[0046] 2) Salt-forming reaction: The temperature in the reactor is controlled at about 20° C. and a certain amount of 70% tert-butyl hydroperoxide is added dropwise, and the temperature is controlled below 35° C. After the addition of tert-butyl hydroperoxide, the reaction is continued for 25 to 30 minutes.

[0047] 3) Condensation reaction: When the temperature in the reactor drops to about 20°C, a quantitative amount of 99% benzoyl chloride and a catalyst are added dropwise, with the catalyst amount being 0.3% of the weight of the benzoyl chloride. The dropping speed and the heating rate are controlled, and the reaction temperature is controlled at 28-32°C. After the addition of benzoyl chloride, the temperature is kept at 28-30°C for 1 hour.

[0048] The preparation of the catalyst comprises: dissolving 30 parts of N-allyl-N-methylaniline and 20 parts of 3-chloropropanol in 60 parts of ethanol, reacting at 80° C. for 24 hours under nitrogen protection, evaporating the solvent, washing and vacuum drying to obtain a first product;

[0049] 40 parts of the first product and 25 parts of 1-(prop-2-en-1-yl)piperidin-4-amine were dissolved in 80 parts of ethyl acetate and 20 parts of methanol, and 0.3 parts of initiator azobisisobutyronitrile was added, stirred, and reacted at 70° C. in a nitrogen atmosphere for 12 hours, and then filtered, washed, and vacuum dried to obtain a second product;

[0050] 40 parts of the second product, 60 parts of 15% sodium hydroxide solution and 20 parts of epichlorohydrin were reacted at 60° C. for 8 hours under nitrogen protection. After the reaction, the catalyst was filtered, washed and dried to obtain the catalyst.

[0051] 4) Static stratification: Sampling and analysis: When the chloride ion content is less than 0.01%, it is qualified, and stirring is stopped, and static stratification is performed. The lower mother liquor is discharged into the acidification kettle for treatment, and the upper product is washed with alkali.

[0052] 5) Alkali washing: add a certain amount of 3% liquid alkali, start stirring and carry out the first alkali washing for about 10 minutes, let it stand and separate, and the lower layer of alkali washing wastewater is discharged into the alkali washing wastewater kettle for treatment; repeat the above alkali washing operation, let it stand and separate, and the lower layer of alkali washing wastewater is also discharged into the alkali washing wastewater kettle for treatment. The residual tert-butyl hydroperoxide content in the product is tested to be qualified when it is less than 0.1%.

[0053] 6) Washing: Add a certain amount of soft water, start stirring and wash for about 10 minutes, let stand and separate, and use the lower layer of washing wastewater as alkali preparation water; repeat the above washing operation, let stand and separate, and the lower layer of washing wastewater is also discharged into the washing wastewater as alkali preparation water. The product is qualified when the pH value is 7.

[0054] 7) Frozen packaging: Lower the kettle temperature to -10℃ before packaging.

[0055] 8) Storage: The product should be stored below 20°C.

[0056] Example 3

[0057] 1) Alkali preparation: a certain amount of water and 30% liquid alkali are delivered into the reactor through a delivery pipeline, stirring is started, and the refrigerated brine is turned on to cool down to 20°C.

[0058] 2) Salt-forming reaction: The temperature in the reactor is controlled at about 20° C. and a certain amount of 70% tert-butyl hydroperoxide is added dropwise, and the temperature is controlled below 35° C. After the addition of tert-butyl hydroperoxide, the reaction is continued for 25 to 30 minutes.

[0059] 3) Condensation reaction: When the temperature in the reactor drops to about 20°C, a quantitative amount of 99% benzoyl chloride and a catalyst are added dropwise, with the catalyst amount being 0.3% of the weight of the benzoyl chloride. The dropping speed and the heating rate are controlled, and the reaction temperature is controlled at 28-32°C. After the addition of benzoyl chloride, the temperature is kept at 28-30°C for 1 hour.

[0060] The preparation of the catalyst comprises: dissolving 25 parts of N-allyl-N-methylaniline and 18 parts of 3-chloropropanol in 53 parts of ethanol, reacting at 80° C. for 24 hours under nitrogen protection, evaporating the solvent, washing and vacuum drying to obtain a first product;

[0061] 36 parts of the first product and 20 parts of 1-(prop-2-en-1-yl)piperidin-4-amine were dissolved in 74 parts of ethyl acetate and 16 parts of methanol, and 0.3 parts of initiator azobisisobutyronitrile was added, stirred, reacted at 70° C. in a nitrogen atmosphere for 12 hours, and filtered, washed, and vacuum dried to obtain a second product;

[0062] 33 parts of the second product, 54 parts of 15% sodium hydroxide solution and 17 parts of epichlorohydrin were reacted at 60° C. for 8 hours under nitrogen protection. After the reaction, the catalyst was filtered, washed and dried to obtain the catalyst.

[0063] 4) Static stratification: Sampling and analysis: When the chloride ion content is less than 0.01%, it is qualified, and stirring is stopped, and static stratification is performed. The lower mother liquor is discharged into the acidification kettle for treatment, and the upper product is washed with alkali.

[0064] 5) Alkali washing: add a certain amount of 3% liquid alkali, start stirring and carry out the first alkali washing for about 10 minutes, let it stand and separate, and the lower layer of alkali washing wastewater is discharged into the alkali washing wastewater kettle for treatment; repeat the above alkali washing operation, let it stand and separate, and the lower layer of alkali washing wastewater is also discharged into the alkali washing wastewater kettle for treatment. The residual tert-butyl hydroperoxide content in the product is tested to be qualified when it is less than 0.1%.

[0065] 6) Washing: Add a certain amount of soft water, start stirring and wash for about 10 minutes, let stand and separate, and use the lower layer of washing wastewater as alkali preparation water; repeat the above washing operation, let stand and separate, and the lower layer of washing wastewater is also discharged into the washing wastewater as alkali preparation water. The product is qualified when the pH value is 7.

[0066] 7) Frozen packaging: Lower the kettle temperature to -10℃ before packaging.

[0067] 8) Storage: The product should be stored below 20°C.

[0068] Example 4

[0069] The preparation process of Example 4 is similar to that of Example 1, except that a stabilizer and a cosolvent are added after washing with water, and the amount of the stabilizer added is 0.6% of the weight of tert-butyl perbenzoate. The stabilizer includes a first stabilizer and a second stabilizer, the mass ratio of the first stabilizer to the second stabilizer is 1:1.5, and the amount of the cosolvent added is 1.5 times the weight of the stabilizer.

[0070] The preparation of the first stabilizer includes: reacting 12 parts of acrylic acid, 20 parts of ethylene glycol methyl ether methacrylate, 30 parts of 2,6-di-tert-butyl-4-vinylphenol and 0.3 parts of potassium persulfate under nitrogen protection, the reaction temperature is 70° C., and the reaction time is 4 hours.

[0071] The preparation of the second stabilizer comprises: S11: reacting 10 parts of maleic anhydride, 15 parts of 4-acetoxystyrene and 0.2 parts of benzoyl peroxide at 80° C. under nitrogen protection for 4 hours, followed by cooling, filtering, washing, drying and other purification steps to obtain a polymer;

[0072] S12: 30 parts of polymer and 15 parts of tetraethylenepentamine are reacted at 140° C. for 4 hours under nitrogen protection, and then purified by cooling, filtering, washing, drying and other steps to obtain the second stabilizer.

[0073] Comparative Example 1

[0074] The preparation processes of Comparative Example 1 and Example 1 are similar, except that no catalyst is added.

[0075] Comparative Example 2

[0076] Comparative Example 2 is similar to Example 4, except that only the first stabilizer is added, and the amount of the first stabilizer added is 0.6% of the weight of tert-butyl perbenzoate.

[0077] Comparative Example 3

[0078] Comparative Example 3 is similar to Example 4, except that only the second stabilizer is added, and the added amount of the second stabilizer is 0.6% of the weight of tert-butyl perbenzoate.

[0079] evaluate

[0080] (1) The conversion rate and yield test results of the products in Examples 1 to 3 and Comparative Example 1 are listed below, as shown in Table 1.

[0081] Table 1

[0082]

[0083] It can be seen from Table 1 that the product conversion rate and yield obtained in Examples 1-3 after adding the catalyst are significantly better than those in Comparative Example 1 in which no catalyst is added.

[0084] (2) In order to evaluate the effect of the stabilizer on the stability of the tert-butyl peroxybenzoate product, the stability test was conducted on the products in Example 1 and Example 4 and Comparative Examples 2 to 3. The test method was to take 3 mg of the dried tert-butyl peroxybenzoate sample and put it into a crucible for DSC test (temperature range 25 to 300° C., heating rate 2° C. / min, nitrogen flow rate 50 mL / min), and the test results are shown in Table 2.

[0085] Table 2

[0086]

[0087] It can be seen from Table 2 that the initial decomposition temperature is significantly increased after adding the stabilizer, and the first stabilizer and the second stabilizer have a synergistic effect on the stability of the product.

[0088] Therefore, the present invention effectively overcomes various shortcomings in the prior art and has a high industrial utilization value. The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology can modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for preparing tert-butyl perbenzoate, characterized in that: The preparation method comprises the following steps: S1: pumping liquid alkali and water into the reactor; S2: adding tert-butyl hydroperoxide to the reactor to carry out a salt-forming reaction; S3: After the salt-forming reaction is completed, benzoyl chloride and a catalyst are added to carry out a condensation reaction to obtain a crude product of tert-butyl perbenzoate; S4: washing the crude product of tert-butyl perbenzoate with alkali and water, and then adding a stabilizer and a co-solvent to obtain a finished product; The catalyst preparation process comprises: Dissolve 20-30 parts of N-allyl-N-methylaniline and 15-20 parts of 3-chloropropanol in 50-60 parts of ethanol, react at 70-80° C. for 20-24 hours under nitrogen protection, evaporate the solvent, wash and dry to obtain a first product; Dissolve 30-40 parts of the first product and 15-25 parts of 1-(prop-2-en-1-yl)piperidin-4-amine in 70-80 parts of ethyl acetate and 10-20 parts of methanol, add 0.2-0.3 parts of azobisisobutyronitrile, react at 60-70° C. for 10-12 hours under nitrogen protection, and filter, wash and dry to obtain a second product; 30-40 parts of the second product, 50-60 parts of an alkaline solution and 12-20 parts of epichlorohydrin are reacted at 50-60° C. for 6-8 hours under nitrogen protection, and the catalyst is obtained after filtering, washing and drying.

2. The preparation method according to claim 1, characterized in that: The amount of the catalyst used is 0.2-0.3% of the amount of the benzoyl chloride used.

3. The preparation method according to claim 1, characterized in that: The stabilizer includes a first stabilizer and a second stabilizer, the first stabilizer is a tert-butylphenol stabilizer, the second stabilizer is an amine stabilizer, and the weight ratio of the first stabilizer to the second stabilizer is 1:(1.5-2).

4. The preparation method according to claim 3, characterized in that: The preparation of the first stabilizer includes: reacting 12 to 15 parts of acrylic acid, 20 to 30 parts of ethylene glycol methyl ether methacrylate, 30 to 40 parts of 2,6-di-tert-butyl-4-vinylphenol and 0.3 to 0.5 parts of potassium persulfate at 70 to 80° C. for 4 to 5 hours under nitrogen protection, and purifying and drying to obtain the first stabilizer.

5. The preparation method according to claim 3, characterized in that: The preparation of the second stabilizer comprises: S11: reacting 10-20 parts of maleic anhydride, 15-35 parts of 4-acetoxystyrene and 0.2-0.3 parts of benzoyl peroxide at 70-80° C. for 4-6 hours under nitrogen protection, followed by cooling, filtering, washing and drying to obtain a polymer; S12: 30-40 parts of the polymer and 15-20 parts of tetraethylenepentamine are reacted at 140-150° C. for 4-5 hours under nitrogen protection, and then cooled, filtered, washed and dried to obtain the second stabilizer.

6. The preparation method according to claim 1, characterized in that: The co-solvent is isooctane, and the amount of the isooctane added is 1 to 1.5 times the amount of the stabilizer added.

7. The preparation method according to claim 1, characterized in that: In step S1, the liquid caustic soda is sodium hydroxide, and the concentration of the liquid caustic soda is 30-40%.

8. The preparation method according to claim 1, characterized in that: In step S2, the concentration of tert-butyl hydroperoxide is 65-70%, the temperature of the salt-forming reaction is 30-35° C., and the time of the salt-forming reaction is 25-30 minutes.

9. The preparation method according to claim 1, characterized in that: In step S3, the temperature of the condensation reaction is 28-32° C., and the time of the condensation reaction is 60-80 minutes.

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