阅读说明：本技术 一种多官能团气干剂的制备方法 (Preparation method of multifunctional gas drying agent ) 是由 张美军 金一丰 张善炯 王杰 赵兴军 于 2021-07-07 设计创作，主要内容包括：本发明提供一种多官能团气干剂的制备方法,该制备方法是通过三羟甲基丙烷和卤代烯烃在碱金属氢氧化物和相转移催化剂存在下通过二步反应获得。本发明通过将三羟甲基丙烷和卤代烯烃的反应设计成两步,并且通过相转移催化剂催化反应进行,可促进传质传热,有利于产品分布变窄,最终得到相对含量较高的三羟甲基丙烷二(甲基)烯丙基醚,达到93％以上,工业化前景高。(The invention provides a preparation method of a multifunctional gas drying agent, which is obtained by two-step reaction of trimethylolpropane and halogenated olefin in the presence of alkali metal hydroxide and a phase transfer catalyst. The invention designs the reaction of trimethylolpropane and halogenated olefin into two steps, and the reaction is carried out by the catalytic reaction of a phase transfer catalyst, so that the mass transfer and heat transfer can be promoted, the narrowing of the product distribution is facilitated, the trimethylolpropane di (methyl) allyl ether with higher relative content is finally obtained, the content is more than 93 percent, and the industrialization prospect is high.)

1. A preparation method of a multifunctional gas drying agent is characterized by comprising the following steps: is obtained by a two-step reaction of trimethylolpropane and halogenated olefin in the presence of an alkali metal hydroxide and a phase transfer catalyst.

2. The method for preparing a multifunctional air drying agent as claimed in claim 1, wherein: the preparation method of the multifunctional gas drying agent specifically comprises the following steps:

(1) uniformly mixing trimethylolpropane and a phase transfer catalyst, and then adding 35-50% by mass of potassium hydroxide aqueous solution for uniformly mixing;

(2) dividing halogenated olefin into 2 parts, adding 1 part of halogenated olefin into the mixture obtained in the step (1) at the temperature of 50-100 ℃ within 1.5-3.5 h, and continuing to perform heat preservation reaction for 1-3 h; standing and layering after the reaction is finished, separating out a water phase and a solid, and retaining an organic phase;

(3) adding a sodium hydroxide aqueous solution with the mass concentration of 35-50% into the organic phase obtained in the step (2), uniformly mixing, adding another 1 part of halogenated olefin at the temperature of 50-100 ℃ within 1.5-3.5 h, and continuously carrying out heat preservation reaction for 1-3 h; standing and layering again after the reaction is finished, separating out a water phase and a solid, and keeping an organic phase;

(4) and (4) adjusting the pH value of the organic phase obtained in the step (3) to 6.5-7.0, and performing reduced pressure distillation and purification.

3. The method for preparing a multifunctional air drying agent as claimed in claim 1 or 2, wherein: the halogenated olefin is one of allyl chloride, allyl bromide, methallyl chloride and methallyl bromide, and the total amount of the halogenated olefin is 2.05-2.4 times of the molar weight of trimethylolpropane.

4. The method for preparing a multifunctional air drying agent as claimed in claim 1 or 2, wherein: the phase transfer catalyst is one of benzyl trimethyl ammonium bromide, tetrabutyl ammonium chloride, trioctylmethyl ammonium bromide, hexadecyl trimethyl ammonium bromide and dodecyl trimethyl ammonium bromide, and the addition amount of the catalyst is 0.8-2% of the mass of the trimethylolpropane.

5. The method for preparing a multifunctional air drying agent as claimed in claim 2, wherein: the molar weight of the potassium hydroxide in the potassium hydroxide aqueous solution is 1.05 times of that of the trimethylolpropane.

6. The method for preparing a multifunctional air drying agent as claimed in claim 2, wherein: the molar weight of the sodium hydroxide in the sodium hydroxide aqueous solution is 1.05 to 1.2 times of that of the trimethylolpropane.

7. The method for preparing a multifunctional air drying agent as claimed in claim 2, wherein: the acid for adjusting the pH is phosphoric acid.

8. A polyfunctional group air-drying agent is characterized in that: is obtained by the preparation method of any one of claims 1 to 7.

9. The multifunctional air drying agent as claimed in claim 8, wherein: the mass percentage of the diether compound in the air drying agent is not lower than 93%.

Technical Field

The invention relates to the technical field of air-drying agent preparation, in particular to a preparation method of a multifunctional group air-drying agent.

Background

The curing of the unsaturated polyester resin is a radical copolymerization reaction, and oxygen in the air plays a role in polymerization inhibition during the curing, so that the surface of the painted surface is sticky. The allyl has the function of auto-polymerization inhibition, the hydrogen on the carbon atom connected with C ═ C in the group is easy to react with peroxy radical generated by oxygen inhibition effect to generate polymer hydroperoxide, the structure can generate strong free radical, the reaction is continued to generate macromolecular compound, thereby avoiding the phenomena of dry and sticky oxygen inhibition, and the function is obvious. The trimethylolpropane di (methyl) allyl ether is used as an air drying agent of the resin, so that the surface of the resin can be dried more quickly, and the polishing performance is better. Commercial products are typically mixtures of three components, including trimethylolpropane mono (meth) allyl ether, hereinafter referred to as monoether; trimethylolpropane di (meth) allyl ether, hereinafter referred to as diether; trimethylolpropane tri (meth) allyl ether, hereinafter referred to as triether, is the most preferable among them in terms of air-drying property.

U.S. Pat. No. 3,33, 502 uses trimethylolpropane and allyl alcohol as raw materials, Hg and BF as catalysts, benzene as solvent to prepare trimethylolpropane allyl ether, and the allyl alcohol used as raw material is a highly toxic product and is expensive, and toxic benzene is used as solvent.

JP60252440 uses trihydroxypropane and allyl chloride as raw materials to prepare trimethylolpropane diallyl ether, but the content of the triether in the product is too high and is more than 8%, and the process needs to be continuously optimized.

CN102040486 takes trihydroxypropane, alkali metal hydroxide and chloropropene as reaction raw materials and butyl ether as a reaction solvent, prepares trihydroxypropane allyl by a method of azeotropic dehydration and etherification, and simultaneously adopts a method of reduced pressure distillation to extract a reaction product. The process uses organic solvents, which increases the cost of solvent recovery and reuse, as well as increases the safety risk of the reaction.

CN1431184A is prepared by taking trihydroxy propane, alkali metal hydroxide and chloropropene as reaction raw materials and selecting part of quaternary ammonium salt as a phase transfer catalyst. The reaction is carried out under normal pressure, the reaction temperature is 60-150 ℃, the boiling point of allyl chloride is 45 ℃, a large amount of energy is consumed for cooling, the production cost is increased, and the content of the target product diether is not higher than 82%.

In summary, the methods for preparing diethers of these patents have more or less defects, and there is no economic and practical technique for preparing air-drying agent with high diether content, so that further development of air-drying agent preparation technique is necessary to solve the above problems.

Disclosure of Invention

Aiming at the problems of the existing air drying agent preparation technology, the invention aims to provide a preparation method of a multifunctional air drying agent. The diether content obtained by the preparation method at least reaches more than 93 percent, the preparation process cost is low, and the industrial prospect is high. The technical scheme of the invention is as follows:

in a first aspect, the present invention provides a method for preparing a multifunctional air drying agent by a two-step reaction of trimethylolpropane and a halogenated olefin in the presence of an alkali metal hydroxide and a phase transfer catalyst.

Further, the preparation method of the multifunctional air drying agent specifically comprises the following steps:

(1) uniformly mixing trimethylolpropane and a phase transfer catalyst, and then adding 35-50% by mass of potassium hydroxide aqueous solution for uniformly mixing;

(2) dividing halogenated olefin into 2 parts, adding 1 part of halogenated olefin into the mixture obtained in the step (1) at the temperature of 50-100 ℃ within 1.5-3.5 h, and continuing to perform heat preservation reaction for 1-3 h; standing and layering after the reaction is finished, separating out a water phase and a solid, and retaining an organic phase;

(3) adding a sodium hydroxide aqueous solution with the mass concentration of 35-50% into the organic phase obtained in the step (2), uniformly mixing, adding another 1 part of halogenated olefin at the temperature of 50-100 ℃ within 1.5-3.5 h, and continuously carrying out heat preservation reaction for 1-3 h; standing and layering again after the reaction is finished, separating out a water phase and a solid, and keeping an organic phase;

(4) and (4) adjusting the pH value of the organic phase obtained in the step (3) to 6.5-7.0, and performing reduced pressure distillation and purification.

Further, the halogenated olefin is one of allyl chloride, allyl bromide, methallyl chloride and methallyl bromide, and the total amount of the halogenated olefin added is 2.05-2.4 times of the molar amount of trimethylolpropane.

Further, the phase transfer catalyst is one of benzyl trimethyl ammonium bromide, tetrabutyl ammonium chloride, trioctyl methyl ammonium bromide, hexadecyl trimethyl ammonium bromide and dodecyl trimethyl ammonium bromide, and the addition amount of the catalyst is 0.8-2% of the mass of the trimethylolpropane.

Further, the molar amount of the potassium hydroxide in the potassium hydroxide aqueous solution is 1.05 times of the molar amount of the trimethylolpropane.

Further, the molar amount of the sodium hydroxide in the sodium hydroxide aqueous solution is 1.05-1.2 times of the molar amount of the trimethylolpropane.

Further, the acid for adjusting the pH is phosphoric acid.

In a second aspect, the invention provides a multifunctional gas drying agent, which is obtained by adopting the preparation method.

Further, the mass percentage of the diether compound in the air drying agent is not less than 93%.

Compared with the prior art, the method has the following outstanding advantages and positive effects:

the invention designs the reaction of trimethylolpropane and halogenated olefin into two steps, and the reaction is carried out by the catalytic reaction of a phase transfer catalyst, so that the mass transfer and heat transfer can be promoted, the narrowing of the product distribution is facilitated, the trimethylolpropane di (methyl) allyl ether with higher relative content is finally obtained, the content is more than 93 percent, and the industrialization prospect is high.

Detailed Description

In the description of the present invention, it is to be noted that those whose specific conditions are not specified in the examples are carried out according to the conventional conditions or the conditions recommended by the manufacturers. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.

The product obtained by the method is trimethylolpropane (methyl) allyl ether, wherein the structure of each component is as follows:

(1) the trimethylolpropane allyl ether comprises the following components in structure:

trimethylolpropane diallyl ether (main component)

Trimethylolpropane monoallyl etherTrimethylol propane triallyl ether

(2) The trimethylolpropane methyl allyl ether comprises the following components in structure:

trimethylolpropane dimethylallyl ether (principal component)

Trimethylolpropane monomethylallyl ether

Trimethylolpropane trimethyallyl ether

Now, taking an example of the synthesis of trimethylol diallyl ether, the following reaction equation is given:

the first step is main reaction:

the second step is main reaction:

example 1

The embodiment provides a preparation method of a multifunctional gas drying agent, which comprises the following steps:

adding 134.2g (1moL) of trimethylolpropane and 1.07g of benzyltrimethylammonium bromide into a pressure reaction kettle, pressing 168.3g (1.05moL) of potassium hydroxide aqueous solution with the mass concentration of 35% into a metering dropwise adding tank, starting stirring, heating to 50 ℃, dropwise adding 124g of allyl bromide, keeping the dropwise adding time for about 1.5 hours, continuing to react for 1 hour after the dropwise adding is finished, stopping stirring, standing for layering, and separating lower-layer saline water and solids out of the reaction kettle through a liquid separator; starting stirring, pressing 120g of sodium hydroxide aqueous solution with the mass concentration of 35% into a metering and dropping tank, heating to 50 ℃, dropping 124g of allyl bromide for about 1.5h, continuing to react for 1h after dropping, stopping stirring, standing for layering, separating the lower-layer brine and solids out of the reaction kettle through a liquid separator, adding a proper amount of phosphoric acid for neutralization until the pH value is 6.5-7.0, distilling low-boiling substances at 105 ℃ and 0.095MPa, heating to 120 ℃ and 150 ℃, and distilling the products under reduced pressure at 35-100 mm Hg. The gas chromatography detects the distribution of the products as follows: trimethylolpropane monoallyl ether was 2.2%, trimethylolpropane diallyl ether was 93.5%, and trimethylolpropane triallyl ether was 4.3%. Through¹The propenyl content of the product is 100ppm by H-NMR detection.

Examples 2 to 4

The embodiment provides a preparation method of a multifunctional gas drying agent, which comprises the following steps:

adding Ag (1moL) trimethylolpropane and Bg catalyst intoPressing a Cg (1.05moL) potassium hydroxide aqueous solution with the mass concentration of D into the pressure reaction kettle through a metering and dripping tank, starting stirring, heating to E ℃, dripping Fg halogenated olefin for about Mh, continuing reacting for Gh after dripping is finished, stopping stirring, standing for layering, and separating lower-layer salt water and solids out of the reaction kettle through a liquid separator; starting stirring, pressing a sodium hydroxide aqueous solution with the mass concentration of Hg being L into a metering dropwise adding tank, heating to I ℃, dropwise adding Fg halogenated olefin, keeping the dropwise adding time about Mh, continuing to react Kh after the dropwise adding is finished, stopping stirring, standing for layering, separating the lower-layer brine and solids out of a reaction kettle through a liquid separator, adding a proper amount of phosphoric acid for neutralization until the pH value is 6.5-7.0, distilling low-boiling-point substances at 105 ℃ and-0.095 MPa, heating to 120 ℃ and 150 ℃, and distilling under reduced pressure at 35-100 mm Hg to obtain the product. The gas chromatography detects the distribution of the product,¹H-NMR measurement of the propenyl group content. The parameters in the examples are shown in Table 1.

TABLE 1 reaction parameters for examples 1-4

Comparative example 1

The procedure of example 1 was followed except that "168.3 g (1.05moL) of 35% by mass aqueous potassium hydroxide solution was introduced into the measuring and dropping tank" in example 1 was changed to "120 g (1.05moL) of 35% by mass aqueous sodium hydroxide solution was introduced into the measuring and dropping tank". The gas chromatography detects the distribution of the products as follows: 7.5% of trimethylolpropane monoallyl ether, 88.5% of trimethylolpropane diallyl ether, and 4% of trimethylolpropane triallyl ether. Through¹The propenyl content of the product was 95ppm by H-NMR.

As can be seen from the comparison of example 1 with comparative example 1, the diether content in the product is reduced from 93.5% to 88.5% after replacing potassium hydroxide with sodium hydroxide, which shows that the distribution is greatly affected by the alkalinity intensity of the step, and the diether content in the product is reduced by the alkalinity reduction of the step.

Comparative example 2

The procedure of example 1 was changed to "120 g (1.05moL) of 35% by mass aqueous sodium hydroxide solution was introduced through the measuring and dropping tank" 168.3g (1.05moL) of 35% by mass aqueous potassium hydroxide solution was introduced through the measuring and dropping tank ", and other conditions and operation procedures were the same as those of example 1. The gas chromatography detects the distribution of the products as follows: trimethylolpropane monoallyl ether 8.3%, trimethylolpropane diallyl ether 76.5%, and trimethylolpropane triallyl ether 15.2%. Through¹The propenyl content of the product was 105ppm by H-NMR.

As can be seen from the comparison between example 1 and comparative example 2, the diether content in the product is reduced from 93.5% to 76.5% after replacing sodium hydroxide with potassium hydroxide, which shows that the distribution is greatly influenced by the alkalinity intensity in the step, the diether content in the product is reduced due to the alkalinity increase in the step, the triether content in the product is increased, and the reaction is moved to the triether direction due to the alkalinity increase.

Comparative example 3

134.2g (1moL) of trimethylolpropane and 1.07g of benzyltrimethylammonium bromide are added into a pressure reaction kettle, 168.3g (1.05moL) of potassium hydroxide aqueous solution with the mass concentration of 35 percent is pressed into the dropwise adding tank through metering, stirring is started, the temperature is raised to 50 ℃, 124g of allyl bromide is dropwise added, the dropwise adding time is about 1.5h, after the dropwise adding is finished, continuously reacting for 1h, then pressing 120g of sodium hydroxide aqueous solution with the mass concentration of 35% into the measuring and dripping tank, heating to 50 ℃, dripping 124g of allyl bromide for about 1.5h, after dripping, and (3) continuing the reaction for 1h, stopping stirring, standing for layering, separating the lower layer of brine and the solids out of the reaction kettle by a liquid separator, adding a proper amount of phosphoric acid for neutralization until the pH value is 6.5-7.0, distilling low-boiling-point substances at 105 ℃ and under the pressure of-0.095 MPa, heating to the temperature of 120 ℃ and 150 ℃, and distilling the products under reduced pressure at 35-100 mm Hg. The gas chromatography detects the distribution of the products as follows: trimethylolpropane monoallyl ether was 12.2%, trimethylolpropane diallyl ether was 81.5%, and trimethylolpropane triallyl ether was 6.3%. Through¹The propenyl content of the product is 100ppm by H-NMR detection.

As can be seen from a comparison of example 1 with comparative example 3, if the lower brine and solids are not separated out of the reactor during the reaction, the diether content in the product is reduced from 93.5% to 81.5%. The reason is that the lower layer of salt water and the solid are separated out of the reaction kettle, on one hand, the water can be removed out of the system, the alkali concentration of the system in the next reaction is not influenced, the dilution effect of the alkali liquor is avoided, the reaction is facilitated, and on the other hand, the mass and heat transfer effect is obviously improved after the inorganic salt is removed.

Comparative example 4

The comparative example examines the experimental results of neutralizing the organic phase by hydrochloric acid and sulfuric acid, and specifically comprises the following steps:

after the organic phase was obtained according to the reaction process of example 1, it was divided into 3 batches, one of which was not neutralized with any acid, and as a result, the propenyl group content of the product was 3000 ppm.

The second organic phase was neutralized with 15% by mass hydrochloric acid (dilute hydrochloric acid), it was difficult to control the pH at 6.5-7.0, and the product was acidic as a result.

The third organic phase was neutralized with 30% sulfuric acid (dilute sulfuric acid), it was difficult to control the pH at 6.5-7.0, and the product was acidic, and the distilled substrate contained a small amount of trimethylolpropane allyl ether sulfate, which was a result of the reaction of sulfuric acid with residual hydroxyl groups in trimethylolpropane allyl ether, which was not favorable for recycling of the substrate.

From a comparison of example 1 with comparative example 4, it can be seen that whether or not neutralization and which acid was used for neutralization had a great influence on the product quality and the propenyl group content therein.

Comparative example 5

Adding 134.2g (1moL) of trimethylolpropane and 1.07g of benzyltrimethylammonium bromide into a pressure reaction kettle, pressing 168.3g (1.05moL) of potassium hydroxide aqueous solution with the mass concentration of 35% into the pressure reaction kettle through a metering dripping tank, pressing 120g of sodium hydroxide aqueous solution with the mass concentration of 35% into the pressure reaction kettle through the metering dripping tank, starting stirring, heating to 50 ℃, dripping 248g of allyl bromide for about 3 hours, and continuing to perform reverse reaction after dripping is finishedStopping stirring and standing for layering for 2 hours, separating the lower layer of brine and solids out of the reaction kettle by a liquid separator, adding a proper amount of phosphoric acid for neutralization until the pH value is 6.5-7.0, distilling low-boiling-point substances at 105 ℃ and under the pressure of-0.095 MPa, heating to 120 ℃ and 150 ℃, and distilling the products under reduced pressure at 35-100 mm Hg. The gas chromatography detects the distribution of the products as follows: trimethylolpropane monoallyl ether was 9.6%, trimethylolpropane diallyl ether was 79.6%, and trimethylolpropane triallyl ether was 10.8%. Through¹The propenyl content of the product was 115ppm by H-NMR.

From a comparison of example 1 with comparative example 5, it can be seen that the reaction is carried out in one portion and without removing solid salts and part of the brine, the distribution of the product is less than ideal and the diether content is only 79.6%.

In conclusion, the invention designs the reaction of the trimethylolpropane and the halogenated olefin into two steps, which can promote mass transfer and heat transfer, is beneficial to narrowing the product distribution, and improves the relative content of the trimethylolpropane di (methyl) allyl ether to more than 93 percent. Trimethylolpropane is easily soluble in water and insoluble in halogenated olefin, the etherified product is easily soluble in halogenated olefin and slightly soluble in saturated sodium chloride aqueous solution, and the catalyst is easily soluble in halogenated olefin and the etherified product and slightly soluble in saturated sodium chloride aqueous solution. Therefore, in the third step, after the reaction is finished and the lower layer of water phase and inorganic salt solid are removed, the content of the catalyst in the organic phase is almost unchanged, and the operation can remove water out of the system on one hand, so that the alkali concentration of the system in the next step of reaction is not influenced, the alkali liquor is prevented from being diluted, the reaction is facilitated, and on the other hand, the mass and heat transfer effects are obviously improved after the inorganic salt is removed. The reaction is carried out in two steps, wherein a product mainly comprising trimethylolpropane mono (methyl) allyl ether is firstly generated, and then the target product is generated through reaction, so that the problems that the reaction degree cannot be controlled and the three ether is higher and the two ether is lower can be avoided, and in the fifth reaction step, the neutralization by phosphoric acid has the beneficial effect that the allyl isomerization to the allyl can be inhibited, because the distillation temperature is up to 120-150 ℃, and the residual alkali at high temperature can promote the allyl isomerization to generate an isomer, thereby influencing the product purity and reducing the product quality.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.