Preparation system of bio-based epoxy (methyl) acrylate

Abstract

The invention discloses a preparation system of bio-based epoxy (methyl) acrylate, which comprises the following steps: (1) etherification reaction: after the reaction is finished, filtering feed liquid in a kettle through a filter I to remove generated salt, and transferring filtrate into a cyclization reaction kettle by using a pump; (2) cyclization reaction: after the reaction is finished, filtering out generated salt from feed liquid in the kettle through a filter II, and transferring filtrate into a water washing kettle by using a pump; (3) washing: obtaining a bio-based epoxy organic phase; (4) crude removal of epichlorohydrin: obtaining a bio-based epoxy resin crude product; (5) finely removing epichlorohydrin to obtain a bio-based epoxy resin product; and (6) esterification reaction: obtaining the bio-based epoxy (methyl) acrylic acid product. The preparation method has the beneficial effects that the process is simple, and the prepared epoxy acrylate is relatively high in purity, relatively low in chromaticity, suitable for various application scenes and particularly suitable for food packaging coatings.

Description

Technical Field

[0001] This invention relates to the field of epoxy acrylate technology, and in particular to a preparation system for bio-based epoxy (meth)acrylates. Background Technology

[0002] Epoxy acrylate is currently the most widely used oligomer in the field of UV curing coatings. It is formed by ring-opening esterification of epoxy resin with acrylic acid or methacrylic acid. Epoxy acrylate has the advantages of readily available raw materials, simple process, and fast curing speed. In addition, the presence of epoxy and hydroxyl groups in the structure enhances the adhesion and chemical resistance of the cured coating. It is widely used as a coating for UV-cured paper, wood, plastic and metal. Traditional epoxy acrylates are mostly made from petrochemical resources, with most of the epoxy resins being bisphenol A (BPA) type epoxy resins. BPA is one of the most widely used industrial compounds in the world. However, in recent years, as people have gained a deeper understanding of the biotoxicity of BPA, many countries have explicitly banned the use of BPA in plastic packaging and containers for food. Therefore, the use of bio-based raw materials to prepare epoxy acrylates has gradually become an urgent need in recent years. In view of the above, it is necessary to improve the existing epoxy acrylate preparation methods to adapt them to the current needs of epoxy acrylate preparation. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a system for preparing bio-based epoxy (meth)acrylates, comprising the following steps: (1) Etherification reaction: The measured bio-based diol and epichlorohydrin are added to the etherification reactor through a pipeline. Steam heating is turned on to raise the temperature. When the temperature inside the reactor reaches 40~45℃, the measured sodium hydroxide aqueous solution is added dropwise. The reaction temperature is controlled at 40-55℃. After the dropwise addition is completed, the temperature is maintained for 1~3 hours. After the reaction is completed, the liquid in the reactor is filtered through a filter to remove the generated salt. Then, the filtrate is transferred into the cyclization reactor by a pump. (2) Cycling reaction: Add the measured amount of catalyst II into the cyclization reactor, and then start adding the measured amount of sodium hydroxide aqueous solution. Control the reaction temperature at 40-55℃. After the addition is completed, keep the temperature for 2-4 hours. After the reaction is completed, filter the liquid in the reactor through filter II to remove the generated salt, and then use a pump to transfer the filtrate into the water washing reactor. (3) Washing: The feed liquid transferred from the cyclization reactor is washed twice with deionized water to obtain a bio-based epoxy organic phase; (4) Crude epichlorohydrin removal: The washed organic phase is transferred to a primary thin-film evaporation system to remove unreacted epichlorohydrin and obtain crude bio-based epoxy resin. (5) Removal of epichlorohydrin: The crude bio-based epoxy resin is transferred to a two-stage thin-film evaporation system to remove epichlorohydrin residue from the crude resin to below 300 ppm. Then it is filtered through a filter to obtain the bio-based epoxy resin product. (6) Esterification reaction: The measured bio-based epoxy resin, polymerization inhibitor, (meth)acrylic acid and catalyst are added to the esterification reactor, heated by steam to 80~120℃, and reacted for 3~5 hours. When the acid value is found to be qualified, the temperature is lowered to 70℃ and the material is discharged to obtain the bio-based epoxy (meth)acrylic acid product.

[0004] As a further supplement to this technical solution, in the etherification reaction, catalyst one is dissolved in epichlorohydrin.

[0005] As a further supplement to this technical solution, the bio-based diol and epichlorohydrin are each provided with corresponding metering tanks.

[0006] As a further supplement to this technical solution, the concentration of sodium hydroxide aqueous solution in the etherification reaction and cyclization reaction is 45%.

[0007] As a further supplement to this technical solution, the distillation conditions of the primary thin-film evaporation system are 500~1000Pa and 60~90℃.

[0008] As a further supplement to this technical solution, the distillation conditions of the secondary thin-film evaporation system are 10~30 Pa and 100~120 °C.

[0009] Its advantages lie in its simple process and the high purity and low color of the prepared epoxy acrylate, making it suitable for a variety of applications, especially for food packaging coatings. Attached Figure Description

[0010] Figure 1 This is a flowchart illustrating the present invention. Detailed Implementation

[0011] To facilitate a clearer understanding of this technical solution for those skilled in the art, the following will be described in conjunction with the appendix. Figure 1 The technical solution of the present invention is described in detail below: A system for preparing bio-based epoxy (meth)acrylates, comprising the following steps: (1) Etherification reaction: The measured bio-based diol and epichlorohydrin are added to the etherification reactor through a pipeline. Steam heating is turned on to raise the temperature. When the temperature inside the reactor reaches 40~45℃, the measured sodium hydroxide aqueous solution is added dropwise. The reaction temperature is controlled at 40-55℃. After the dropwise addition is completed, the temperature is maintained for 1~3 hours. After the reaction is completed, the liquid in the reactor is filtered through a filter to remove the generated salt. Then, the filtrate is transferred into the cyclization reactor by a pump. (2) Cycling reaction: Add the measured amount of catalyst II into the cyclization reactor, and then start adding the measured amount of sodium hydroxide aqueous solution. Control the reaction temperature at 40-55℃. After the addition is completed, keep the temperature for 2-4 hours. After the reaction is completed, filter the liquid in the reactor through filter II to remove the generated salt, and then use a pump to transfer the filtrate into the water washing reactor. (3) Washing: The feed liquid transferred from the cyclization reactor is washed twice with deionized water to obtain a bio-based epoxy organic phase; (4) Crude epichlorohydrin removal: The washed organic phase is transferred to a primary thin-film evaporation system to remove unreacted epichlorohydrin and obtain crude bio-based epoxy resin. (5) Removal of epichlorohydrin: The crude bio-based epoxy resin is transferred to a two-stage thin-film evaporation system to remove epichlorohydrin residue from the crude resin to below 300 ppm. Then it is filtered through a filter to obtain the bio-based epoxy resin product. (6) Esterification reaction: The measured bio-based epoxy resin, polymerization inhibitor, (meth)acrylic acid and catalyst are added to the esterification reactor, heated by steam to 80~120℃, and reacted for 3~5 hours. When the acid value is found to be qualified, the temperature is lowered to 70℃ and the material is discharged to obtain the bio-based epoxy (meth)acrylic acid product.

[0012] In the etherification reaction, catalyst one is dissolved in epichlorohydrin.

[0013] Bio-based glycols and epichlorohydrin are each equipped with corresponding metering tanks.

[0014] In the etherification and cyclization reactions, the concentration of sodium hydroxide aqueous solution is 45%.

[0015] The distillation conditions for the primary thin-film evaporation system are 500~1000Pa and 60~90℃.

[0016] The distillation conditions for the two-stage thin-film evaporation system are 10~30 Pa and 100~120 °C.

[0017] The above technical solutions only embody the preferred technical solutions of the present invention. Any modifications that may be made by those skilled in the art to certain parts thereof embody the principles of the present invention and fall within the protection scope of the present invention.

Claims

1. A system for preparing bio-based epoxy (meth)acrylate, characterized in that, Includes the following steps: (1) Etherification reaction: The measured bio-based diol and epichlorohydrin are added to the etherification reactor through a pipeline. Steam heating is turned on to raise the temperature. When the temperature inside the reactor reaches 40~45℃, the measured sodium hydroxide aqueous solution is added dropwise. The reaction temperature is controlled at 40-55℃. After the dropwise addition is completed, the temperature is maintained for 1~3 hours. After the reaction is completed, the liquid in the reactor is filtered through a filter to remove the generated salt. Then, the filtrate is transferred into the cyclization reactor by a pump. (2) Cycling reaction: Add the measured amount of catalyst II into the cyclization reactor, and then start adding the measured amount of sodium hydroxide aqueous solution. Control the reaction temperature at 40-55℃. After the addition is completed, keep the temperature for 2-4 hours. After the reaction is completed, filter the liquid in the reactor through filter II to remove the generated salt, and then use a pump to transfer the filtrate into the water washing reactor. (3) Washing: The feed liquid transferred from the cyclization reactor is washed twice with deionized water to obtain a bio-based epoxy organic phase; (4) Crude epichlorohydrin removal: The washed organic phase is transferred to a primary thin-film evaporation system to remove unreacted epichlorohydrin and obtain crude bio-based epoxy resin. (5) Removal of epichlorohydrin: The crude bio-based epoxy resin is transferred to a two-stage thin-film evaporation system to remove epichlorohydrin residue from the crude resin to below 300 ppm. Then it is filtered through a filter to obtain the bio-based epoxy resin product. (6) Esterification reaction: The measured bio-based epoxy resin, polymerization inhibitor, (meth)acrylic acid and catalyst are added to the esterification reactor, heated by steam to 80~120℃, and reacted for 3~5 hours. When the acid value is found to be qualified, the temperature is lowered to 70℃ and the material is discharged to obtain the bio-based epoxy (meth)acrylic acid product.

2. The preparation system for a bio-based epoxy (meth)acrylate according to claim 1, characterized in that, In the etherification reaction, catalyst one is dissolved in epichlorohydrin.

3. The preparation system for a bio-based epoxy (meth)acrylate according to claim 2, characterized in that, The bio-based diol and epichlorohydrin are each equipped with a corresponding metering tank.

4. The preparation system for a bio-based epoxy (meth)acrylate according to claim 1, characterized in that, The concentration of sodium hydroxide aqueous solution in the etherification and cyclization reactions is 45%.

5. The preparation system for a bio-based epoxy (meth)acrylate according to claim 1, characterized in that, The distillation conditions of the primary thin-film evaporation system are 500~1000Pa and 60~90℃.

6. The preparation system for a bio-based epoxy (meth)acrylate according to claim 1, characterized in that, The distillation conditions of the two-stage thin-film evaporation system are 10~30 Pa and 100~120 °C.

Images