阅读说明：本技术 丙烯酸(3-乙基-3-氧杂环丁烷基)甲酯的制备方法及应用 (Preparation method and application of (3-ethyl-3-oxetanyl) methyl acrylate ) 是由 郑万强 姚慧玲 国凤玲 耿超群 谢呈鹏 王红乐 于 2019-10-29 设计创作，主要内容包括：本公开提供了丙烯酸(3-乙基-3-氧杂环丁烷基)甲酯的制备方法及应用,包括N个部分,第N部分的步骤为：1.以丙烯酸甲酯、3-乙基-3-羟甲基氧杂环丁烷作为原料,以第N-1部分的釜残物料作为催化剂,进行酯交换反应,反应过程中将甲醇和丙烯酸甲酯共沸物采出；2.将第N部分的步骤1反应后的物料依次采出丙烯酸甲酯馏分、前馏分及产品,并剩余釜残物料；第1部分的步骤为：1)以丙烯酸甲酯、3-乙基-3-羟甲基氧杂环丁烷作为原料,以介孔硅胶负载有机锡作为催化剂,进行酯交换反应,反应过程中将甲醇和丙烯酸甲酯共沸物采出；2)将第1部分的步骤1)反应后的物料依次采出丙烯酸甲酯馏分、前馏分及产品,并剩余釜残物料。(The present disclosure provides a process for the preparation of (3-ethyl-3-oxetanyl) methyl acrylate and its use, comprising N parts, the steps of the N part being: 1. taking methyl acrylate and 3-ethyl-3-hydroxymethyl oxetane as raw materials, taking the kettle residue material of the part N-1 as a catalyst, and carrying out ester exchange reaction, wherein an azeotrope of methanol and methyl acrylate is extracted in the reaction process; 2. sequentially extracting methyl acrylate fraction, front fraction and products from the material reacted in the step 1 in the Nth part, and remaining kettle residue material; the steps of part 1 are: 1) methyl acrylate and 3-ethyl-3-hydroxymethyl oxetane are used as raw materials, mesoporous silica gel loaded organic tin is used as a catalyst, ester exchange reaction is carried out, and an azeotrope of methanol and methyl acrylate is extracted in the reaction process; 2) sequentially extracting methyl acrylate fraction, front fraction and products from the materials reacted in the step 1) in the part 1, and remaining kettle residue materials.)

1. A process for the preparation of (3-ethyl-3-oxetanyl) methyl acrylate, characterized in that it comprises N moieties,

the step of the Nth part is as follows:

(1) taking methyl acrylate and 3-ethyl-3-hydroxymethyl oxetane as raw materials, taking the kettle residue material of the part N-1 as a catalyst, and carrying out ester exchange reaction, wherein an azeotrope of methanol and methyl acrylate is extracted in the reaction process;

(2) sequentially extracting methyl acrylate fraction, front fraction and a product of 3-ethyl-3-oxetanyl methyl acrylate from the material reacted in the step (1) in the Nth part, and remaining kettle residue material;

the steps of part 1 are:

(1) methyl acrylate and 3-ethyl-3-hydroxymethyl oxetane are used as raw materials, dibutyltin oxide is used as a catalyst, ester exchange reaction is carried out, and an azeotrope of methanol and methyl acrylate is extracted in the reaction process;

(2) sequentially extracting methyl acrylate fraction, front fraction and a product of 3-ethyl-3-oxetanyl methyl acrylate from the material reacted in the step (1) in the part 1, and remaining kettle residue material;

wherein N is a natural number greater than 1.

2. The process according to claim 1, wherein the methyl acrylate fraction of the N-1 st part is fed as an auxiliary raw material in the step (1) of the N-th part.

3. The method of claim 1, wherein the step (2) of the nth part is: mixing the material obtained after the reaction in the step (1) in the part N with the front fraction in the part N-1, sequentially collecting a methyl acrylate fraction, the front fraction and a product methyl acrylate (3-ethyl-3-oxetanyl) ester, and remaining the residual material.

4. The process according to claim 1, wherein the molar ratio of methyl acrylate to 3-ethyl-3-hydroxymethyloxetane in said N fractions is 1 to 10: 1; more preferably 2 to 4: 1.

5. The method according to claim 1, wherein the dibutyltin oxide is added in the step (1) in the part 1 in an amount of 1 to 8% by weight based on the 3-ethyl-3-hydroxymethyloxetane.

6. The preparation method according to claim 1, wherein the reflux ratio of the methanol and methyl acrylate azeotrope used in the reaction process in the N parts is 1-10: 1.

7. The method according to claim 1, wherein N is 2 to 5.

8. The process as claimed in claim 1, wherein the 3-ethyl-3-hydroxymethyl oxetane is prepared by heating a mixture of diethyl carbonate, trimethylolpropane and potassium hydroxide to 125 ± 2 ℃ for reaction, heating to 140 ± 2 ℃ for ethanol distillation, and vacuum distilling off 143-146 ℃ fraction as 3-ethyl-3-hydroxymethyl oxetane.

9. The preparation method of claim 1, wherein cetyl trimethyl ammonium bromide is used as a template, ethyl orthosilicate is used as a raw material, dibutyltin dilaurate is added to react under the action of ammonia water to form silica gel, the silica gel is roasted to form mesoporous silica gel, the mesoporous silica gel is added to a solution containing dibutyltin maleate and stannous octoate to be soaked, and the soaked mesoporous silica gel is dried to obtain the mesoporous silica gel loaded with organic tin;

preferably, the reaction temperature for forming the silica gel is 45-55 ℃;

preferably, the pH of the reaction system for forming the silica gel is 8-9;

preferably, the roasting temperature is 350-400 ℃;

preferably, the drying is vacuum drying.

10. A method for preparing (3-ethyl-3-oxetanyl) methyl acrylate according to any one of claims 1 to 8 or the use of (3-ethyl-3-oxetanyl) methyl acrylate for preparing 3D printing photosensitive resins;

preferably, (3-ethyl-3-oxetanyl) methyl acrylate and γ - (methacryloyloxy) propyltrimethoxysilane are used as raw materials of the 3D printing photosensitive resin.

Technical Field

The disclosure belongs to the field of organic synthesis, relates to preparation of 3D printing photosensitive resin, and particularly relates to a preparation method and application of (3-ethyl-3-oxetanyl) methyl acrylate.

Background

Acrylic acid (3-ethyl-3-oxetanyl) methyl ester is a multifunctional active monomer, has the characteristics of olefin, oxygen heterocycle and ester compounds, and because ester groups contain a hydrophilic hydroxyl group, the polymer is an important hydrophilic polymer and is widely applied to the fields of preparation of medical polymer materials, coatings, printing ink, adhesives and the like. And also has an oxygen heterocyclic structure in its molecule, and is often used as a prepolymer and a reactive diluent for cationic photopolymerization. The cationic photocuring material is widely applied to the fields of coatings, electronic products, rapid forming and the like.

At present, the synthesis research of acrylic acid (3-ethyl-3-oxetanyl) methyl ester is less in China, and the main synthesis methods mainly comprise a direct esterification method and an ester exchange method. Prepared by the direct esterification reaction of 3-ethyl-3-hydroxymethyloxetane with acrylic acid, but due to the direct esterification method, a water-resistant catalyst such as concentrated sulfuric acid, p-toluenesulfonic acid, etc. must be used. The latter is prepared by the transesterification of 3-ethyl-3-hydroxymethyl oxetane with lower alkyl acrylate, the transesterification process has a larger space in the selection of the catalyst, and the traditional transesterification catalyst mainly comprises concentrated sulfuric acid, p-toluenesulfonic acid, sodium methoxide, potassium hydroxide and the like.

The main disadvantages of the catalysts used in either the direct esterification or transesterification processes are their low catalytic efficiency, high use level, difficulty in separation from the product after reaction, inability to be reused, and the general need for neutralization resulting in waste water, etc.

Disclosure of Invention

In order to solve the defects of the prior art, one of the purposes of the present disclosure is to provide a preparation method and an application of (3-ethyl-3-oxetanyl) methyl acrylate, wherein a mesoporous silica gel is used for supporting an organotin catalyst in a synthesis process, and the catalyst has the advantages of small using amount, high catalytic efficiency, high reaction speed, few side reactions, reusability and the like.

In order to achieve the purpose, the technical scheme of the disclosure is as follows:

a process for the preparation of (3-ethyl-3-oxetanyl) methyl acrylate comprising N moieties,

the step of the Nth part is as follows:

(1) taking methyl acrylate and 3-ethyl-3-hydroxymethyl oxetane as raw materials, taking the kettle residue material of the part N-1 as a catalyst, and carrying out ester exchange reaction, wherein an azeotrope of methanol and methyl acrylate is extracted in the reaction process;

(2) sequentially extracting methyl acrylate fraction, front fraction and a product of 3-ethyl-3-oxetanyl methyl acrylate from the material reacted in the step (1) in the Nth part, and remaining kettle residue material;

the steps of part 1 are:

(1) methyl acrylate and 3-ethyl-3-hydroxymethyl oxetane are used as raw materials, mesoporous silica gel loaded organic tin is used as a catalyst, ester exchange reaction is carried out, and an azeotrope of methanol and methyl acrylate is extracted in the reaction process;

(2) sequentially extracting methyl acrylate fraction, front fraction and a product of 3-ethyl-3-oxetanyl methyl acrylate from the material reacted in the step (1) in the part 1, and remaining kettle residue material;

wherein N is a natural number greater than 1.

Preferably, the methyl acrylate fraction of the N-1 st part is added as an additional raw material in the step (1) of the N-th part. The raw material of the previous batch can be further utilized.

In order to separate the product possibly existing in the front fraction of the advancing batch and improve the product yield, preferably, the step (2) of the Nth part is as follows: mixing the material obtained after the reaction in the step (1) in the part N with the front fraction in the part N-1, sequentially collecting a methyl acrylate fraction, the front fraction and a product methyl acrylate (3-ethyl-3-oxetanyl) ester, and remaining the residual material.

Preferably, the molar ratio of methyl acrylate to 3-ethyl-3-hydroxymethyl oxetane in the N parts is 1-10: 1. More preferably 2 to 4: 1.

Preferably, the reflux ratio of the methanol to the methyl acrylate azeotrope in the reaction process of the N parts is 1-10: 1.

Preferably, N is 2-5.

Preferably, the amount of loaded organotin in mesoporous silica gel in the step (1) of the part 1 is 1 to 8% by weight of the 3-ethyl-3-hydroxymethyloxetane. More preferably 2 to 4%.

The 3-ethyl-3-hydroxymethyl oxetane described in the present disclosure may be a commercially available product or may be synthesized by itself.

The disclosure also provides a preparation method of the 3-ethyl-3-hydroxymethyl oxetane, which comprises the steps of heating a mixture of diethyl carbonate, trimethylolpropane and potassium hydroxide to 125 +/-2 ℃ for reaction, heating to 140 +/-2 ℃, evaporating ethanol, and then distilling a fraction at 143-146 ℃ in vacuum to obtain the 3-ethyl-3-hydroxymethyl oxetane.

In order to provide the catalytic effect of the mesoporous silica gel supported with the organotin, the disclosure is preferable that the preparation method of the mesoporous silica gel supported with the organotin comprises the following steps: cetyl trimethyl ammonium bromide is used as a template, ethyl orthosilicate is used as a raw material, dibutyltin dilaurate is added to react under the action of ammonia water to form silica gel, then the silica gel is roasted to form mesoporous silica gel, then the mesoporous silica gel is added into a solution containing dibutyltin maleate and stannous octoate to be soaked, and the soaked mesoporous silica gel is dried to obtain the mesoporous silica gel loaded with organic tin.

Further preferably, the reaction temperature for forming the silica gel is 40-50 ℃.

Further preferably, the reaction system for forming the silica gel has a pH of 8 to 9.

Further preferably, the roasting temperature is 350-400 ℃.

More preferably, the drying is vacuum drying.

Further preferably, the preparation process comprises the following steps:

sequentially adding deionized water, hexadecyl trimethyl ammonium bromide, ethyl orthosilicate and dibutyltin dilaurate into a reaction kettle, stirring for 1-2 h at 40-50 ℃, gradually dropwise adding ammonia water into the system, adjusting the pH value to 8-9, and continuously reacting for 3-4 h at a constant temperature of 50 ℃. After the reaction is stopped, spray drying and granulating, roasting at 350-400 ℃ for 3-4 h, and grinding. Then dipping the catalyst in an ethanol solution of dibutyltin maleate and stannous octoate, filtering the solution after nighttime, and drying the filtered solution in vacuum at the temperature of 80-90 ℃ to obtain the mesoporous silica gel supported organotin catalyst, wherein the loading rate is 30.6-40% by calculation.

Further preferably, the mass ratio of the hexadecyl trimethyl ammonium bromide to the ethyl orthosilicate to the dibutyltin dilaurate is as follows: 0.1-0.5: 2-3: 0.2-0.3.

Further preferably, the molar ratio of dibutyltin dilaurate to dibutyltin maleate to stannous octoate is 1: 6-8: 2-4.

Preferably, the dosage of the ethanol is 2-3 times of the total mass of the dibutyltin maleate and the stannous octoate.

The organic tin catalyst is a transesterification catalyst with a high catalytic effect in the prior art, however, according to the records in the prior art, the organic tin catalyst and the organic titanium catalyst are difficult to be completely separated after the reaction is finished, so that the catalytic efficiency of the separated catalyst is unstable, and the catalyst is difficult to be recycled. Experiments show that the yield of the obtained product is higher, and when the kettle residue material obtained by distilling out methyl acrylate fraction, front fraction and (3-ethyl-3-oxetanyl) methyl acrylate product is used as a catalyst for next batch of transesterification reaction, the product with higher yield can be obtained through better catalytic effect, and the yield of the product prepared by using the kettle residue material as the catalyst is increased along with the increase of product batches.

Since the (3-ethyl-3-oxetanyl) methyl acrylate has the characteristics of olefin, oxygen heterocycle and ester compounds, chemical reactions such as ring opening, polymerization, addition, hydrolysis and the like can occur under certain conditions. It is therefore another object of the present disclosure to provide a method for preparing the above (3-ethyl-3-oxetanyl) methyl acrylate or the use of (3-ethyl-3-oxetanyl) methyl acrylate in the preparation of 3D printing photosensitive resins. The 3-ethyl-3-oxetanyl methyl acrylate not only participates in the photocuring reaction of a system, but also has the function of diluting and adjusting the photocuring coating, thereby avoiding using other diluents, and having the advantages of environmental protection, no toxicity, no peculiar smell, small skin irritation and the like. The prepared 3D printing photosensitive resin has the advantages of low shrinkage rate, high gel content and high curing speed.

The application process comprises the following steps:

(1) preparation of prepolymer: adding epoxy acrylate, 3-ethyl-3-oxetanyl methyl methacrylate, gamma- (methacryloyloxy) propyl trimethoxy silane and dibenzoyl peroxide serving as an initiator into a polymerization kettle in sequence, stirring for 6-7 h at 65-70 ℃, and degassing in a vacuum drying oven to obtain a transparent prepolymer;

(2) preparation of 3D printing photosensitive resin: uniformly stirring 23-30 wt% of cabot white carbon black ts530, 3-10 wt% of merck MOK2638 flatting agent, 0.5-2 wt% of SN-DEFAAMER 1350 defoaming agent, 2-3 wt% of alpha-alpha dimethoxybenzene phthalein ketal photoinitiator and 60-70 wt% of prepolymer prepared in the step (1), filling argon, shading and sealing for storage. During the use, will join in marriage 3D and print photosensitive resin, put into the curing light source and be the 3D printer resin tank of 405nm wavelength, even levelling carries out 3D and prints, obtains the cured resin sample.

Preferably, the molar ratio of the epoxy acrylate to the (3-ethyl-3-oxetanyl) methyl methacrylate to the gamma- (methacryloyloxy) propyltrimethoxysilane is: 2-3: 1: 0.1-0.2.

Preferably, the amount of the dibenzoyl peroxide is 0.02-0.05% of the total weight.

The beneficial effect of this disclosure does:

(1) the method adopts methyl acrylate as a raw material, and the excessive methyl acrylate is used as an entrainer in the reaction, so that the synthesis reaction is ensured to be carried out in the positive direction, and other organic solvents are not added as the entrainer, so that the pollution is reduced; the residual methyl acrylate is distilled and collected to be used as the reaction raw material of the next batch, and the utilization rate of the raw material is high.

(2) The method adopts the mesoporous silica gel loaded organic tin catalyst to catalyze the transesterification reaction of the lower alkyl acrylate and the 3-ethyl-3-hydroxymethyl oxetane, and has the advantages of high activity, high selectivity, small dosage and high yield. Good chemical and thermal stability, no corrosion to equipment and recycling, thereby reducing production cost and avoiding environmental pollution.

(3) According to the method, the mesoporous silica gel loaded organic tin is used as the catalyst to prepare the (3-ethyl-3-oxetanyl) methyl acrylate, the catalyst does not need to be completely separated, and the catalytic efficiency is increased in batches along with the increase of the using batches of the catalyst in a 5-kettle manner.

(4) The product prepared by adopting the mesoporous silica gel loaded organic tin as the catalyst has good stability, high purity and high yield.

(5) When the 3-ethyl-3-oxetanyl methyl acrylate prepared by the method is applied to 3D printing photosensitive resin, the methyl acrylate not only participates in the photocuring reaction of a system, but also has the effect of diluting and adjusting the photosensitive resin, so that other diluents are avoided, and the photocuring coating has the advantages of environmental friendliness, no toxicity, no peculiar smell, small skin irritation and the like.

(6) The 3D printing photosensitive resin containing acrylic acid (3-ethyl-3-oxetanyl) methyl ester prepared by the method has the advantages of low shrinkage rate, high gel content, high curing speed and the like.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The still residue material refers to a material remaining after a methanol and methyl acrylate azeotrope, a methyl acrylate fraction, a front fraction and a product methyl acrylate (3-ethyl-3-oxetanyl) methyl ester are sequentially separated from a material after an esterification reaction by a fractionation method.

The chemical structural formula of the 3-ethyl-3-hydroxymethyl oxetane is as follows:

the chemical structural formula of the (3-ethyl-3-oxetanyl) methyl acrylate is as follows: