A method for preparing electronic grade triglycidyl isocyanurate

Abstract

The invention discloses a preparation method of electronic-grade triglycidyl isocyanurate, belongs to the technical field of triglycidyl isocyanurate, and comprises the following steps: synthesis reaction, cyclization reaction, and post-treatment; in the cyclization reaction, the synthesis liquid is cooled to 20-25 DEG C, sodium methoxide is added to the synthesis liquid in five batches under stirring, the first batch of sodium methoxide is reacted after the addition is completed, the second batch of sodium methoxide is added, the reaction is continued; the third batch of sodium methoxide is added, the reaction is continued; the fourth batch of sodium methoxide is added, the reaction is continued; the rotation speed is increased, the fifth batch of sodium methoxide is added, the reaction is continued, and a cyclization liquid is obtained; the invention can avoid product defects caused by catalyst residues, and can avoid the generation of hydroxide anions, thereby greatly reducing the occurrence of side reactions, greatly improving the yield, avoiding the process wastewater treatment link, and saving process costs.

Description

Technical Field

[0001] The invention relates to the technical field of triglycidyl isocyanurate, and in particular to a method for preparing electronic-grade triglycidyl isocyanurate. Background Art

[0002] Triglycidyl isocyanurate (TGIC) is a white crystal with excellent heat resistance, weather resistance, light resistance, corrosion resistance, chemical resistance and mechanical properties. It is mainly used as a curing agent for carboxyl polyester and carboxyl acrylic resin powder coatings. It can also be used to manufacture electrical insulation material laminates, printed circuits, various tools, adhesives, plastic stabilizers, etc.

[0003] At present, the preparation method of triglycidyl isocyanurate is mainly a "two-step method", specifically: epichlorohydrin and cyanuric acid undergo a ring-opening reaction under the action of a catalyst (quaternary ammonium salt phase transfer catalyst) to generate an intermediate product, 3-chloro-2-hydroxypropyl isocyanurate, and 3-chloro-2-hydroxypropyl isocyanurate undergoes a ring-closing reaction under the action of sodium hydroxide to obtain a crude triglycidyl isocyanurate, and sodium chloride and hexanol are obtained at the same time. Excessive epichlorohydrin needs to be added in the reaction, which serves as both a reaction raw material and a solvent for triglycidyl isocyanurate. After the reaction, the epichlorohydrin is recycled. In order to obtain solid triglycidyl isocyanurate, methanol is used as a solvent to crystallize it to obtain triglycidyl isocyanurate powder, and methanol is recycled after the crystallization is completed. Then the triglycidyl isocyanurate is granulated and dried to obtain the product electronic grade triglycidyl isocyanurate; the specific reaction route is:

[0004] 1. Synthesis reaction: Epichlorohydrin and cyanuric acid undergo a synthesis reaction under the action of a catalyst to generate 3-chloro-2-hydroxypropyl isocyanurate. The chemical reaction equation is as follows:

[0005]

[0006] 2. Cyclization reaction: The generated 3-chloro-2-hydroxypropyl isocyanurate reacts with sodium hydroxide to remove chloride ions and cyclize to electronic grade triglycidyl isocyanurate. The chemical reaction equation is as follows:

[0007]

[0008] Chinese patent CN102174040A discloses a method for preparing electronic-grade triglycidyl isocyanurate, comprising the following steps: adding a certain proportion of epichlorohydrin, cyanuric acid, a quaternary ammonium salt phase transfer catalyst (tetramethylammonium chloride and / or benzyltriethylammonium chloride) and water to react, then adding alkali, and removing the corresponding solid inorganic salt by filter pressing, and then the crude product is crystallized, centrifuged, crushed and dried to obtain electronic-grade triglycidyl isocyanurate. The purity of TGIC obtained by this method reaches 99.5%, which can reach the electronic grade level.

[0009] Chinese patent CN101367796A discloses a method for producing TGIC, comprising the following steps: a synthesis step: at 68-105°C, epichlorohydrin and cyanuric acid are reacted in the presence of a catalyst (tetramethylammonium chloride and benzyltrimethylammonium chloride) and water in a ratio of 8-11:1 by weight, after the reaction is completed, alkali (sodium hydroxide) is added when the temperature is cooled to 25-30°C, and the reaction is carried out at 30-36°C. After the reaction is completed, the synthetic material is filtered and collected; a distillation step: the synthetic material is distilled with water at 65-110°C and a vacuum degree of 0.09-0.1MPa; (c) an alcohol precipitation step: after the distillation is completed, 20-21% by weight of methanol is added for freeze crystallization, and when the reaction liquid is cooled to 5-10°C, freezing is stopped to obtain a crystal material; the crystal material is centrifuged, discharged, and then dried at 55-90°C to obtain powdery triglycidyl isocyanurate.

[0010] However, the phase transfer catalyst used in the above two patents is difficult to be removed in the subsequent process, resulting in unstable curing speed of the product in powder coating applications. In addition, the product needs to be washed several times during purification, and the solid alkali and by-product salt in the washing system produce a lot of wastewater. In addition, the washing is not thorough because water and epichlorohydrin are partially miscible, and the product purification cost is high.

[0011] Chinese patent CN114989150A discloses a method for preparing electronic grade triglycidyl isocyanurate, which comprises: preparing the product without a catalyst, mixing cyanuric acid with an excess of epichlorohydrin, dissolving the cyanuric acid in epichlorohydrin and generating a condensation intermediate with epichlorohydrin under catalyst-free and water-free conditions, thereby avoiding the absence of catalyst residue in the product and reducing the chlorine content of the product; the invention utilizes anhydrous carbonate to remove hydrogen chloride, and controls the dosage ratio of the condensation intermediate to the anhydrous carbonate, so that the carbonate forms sodium chloride and sodium bicarbonate in the reaction of removing hydrogen chloride. The anhydrous production fundamentally solves the problem of high-salt and high-concentration COD wastewater produced by traditional production processes. However, water is a reaction product in the cyclization reaction, and it is also the reaction site and catalyst. When there is no water in the reaction system, sodium hydroxide and epichlorohydrin are incompatible, and the probability of contacting the intermediate product is very low, resulting in a very slow reaction. However, as the reaction proceeds, more and more water will cause the reaction site to be filled with a large number of hydroxide anions. The active hydroxide anions will undergo a substitution reaction with the chlorine in the intermediate product, resulting in the production of hexavalent alcohol by-products, thereby reducing the yield. Summary of the invention

[0012] In view of the deficiencies in the prior art, the present invention provides a method for preparing electronic-grade triglycidyl isocyanurate, which can avoid product defects caused by catalyst residues and can avoid the generation of hydroxide anions, thereby greatly reducing the occurrence of side reactions, greatly improving the yield, avoiding the process wastewater treatment link, and saving process costs.

[0013] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0014] A method for preparing electronic grade triglycidyl isocyanurate, comprising the following steps: synthesis reaction, cyclization reaction, and post-treatment;

[0015] In the synthesis reaction, epichlorohydrin is added into the reactor, stirring is started, the speed is controlled to be 200 r / min, and then cyanuric acid and methanol are added in sequence, the temperature is controlled at 65-110° C., and the reaction is stirred for 6-10 hours to obtain a synthetic liquid;

[0016] In the synthesis reaction, the weight ratio of epichlorohydrin, cyanuric acid and methanol is 538-646:50:2.5-7.5;

[0017] The cyclization reaction comprises cooling the synthesis liquid to 20-25° C., adding sodium methoxide to the synthesis liquid in five batches at a rotation speed of 200 r / min, reacting for 20-24 min after the first batch of sodium methoxide is added, then adding the second batch of sodium methoxide, and continuing the reaction for 20-24 min; then adding the third batch of sodium methoxide, and continuing the reaction for 20-24 min; then adding the fourth batch of sodium methoxide, and continuing the reaction for 20-24 min; adjusting the rotation speed to 230 r / min, then adding the fifth batch of sodium methoxide, and continuing the reaction for 20-24 min to obtain a cyclization liquid;

[0018] In the cyclization reaction, the weight ratio of the first batch of sodium methoxide, the second batch of sodium methoxide, the third batch of sodium methoxide, the fourth batch of sodium methoxide, and the fifth batch of sodium methoxide is 15:12:12:12:12;

[0019] The weight ratio of cyanuric acid in the synthesis reaction to the total weight of five batches of sodium methoxide in the cyclization reaction is 50:63;

[0020] The post-treatment is to treat the cyclized liquid by a vacuum filtration device, and then the filtrate is decompressed and arranged, and the distillation is stopped after the distillation temperature rises to 105° C., and then methanol is added for recrystallization. The temperature of the recrystallization process is maintained at -10° C. and the time is maintained at 2.5 hours. After vacuum filtration for 1 hour, the solid is dried at 70° C. for 5 hours to obtain triglycidyl isocyanurate;

[0021] The weight-to-volume ratio of the cyanuric acid in the synthesis reaction to the total weight of the methanol in the post-treatment is 50 g:400 mL.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The present invention uses methanol as a co-solvent / catalyst in the addition stage, thereby avoiding the problem of phase transfer catalyst remaining in the product, thereby causing unstable curing time of the powder coating;

[0024] (2) The present invention uses sodium methoxide instead of sodium hydroxide in the cyclization stage, which has two advantages: first, it promotes the cyclization reaction to proceed in the positive direction; second, it avoids the generation of hydroxide anions, thereby greatly reducing the occurrence of side reactions and improving the yield;

[0025] (3) The present invention can be directly distilled after the cyclization reaction through filter pressing, eliminating the process steps of water washing and stratification required in the traditional process, avoiding the process wastewater treatment link, and saving process costs;

[0026] (4) The present invention improves the utilization rate of cyanuric acid and epichlorohydrin and realizes a clean production process;

[0027] (5) The electronic grade triglycidyl isocyanurate prepared by the present invention has an epoxy equivalent of 101.7-102.0 eg / g, a total chlorine content of 0.09-0.1%, an ECH residue of 69-72 ppm, and a yield of 93.8-95%. DETAILED DESCRIPTION

[0028] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation methods of the present invention are now described.

[0029] Example 1

[0030] A method for preparing electronic grade triglycidyl isocyanurate, specifically comprising:

[0031] 1. Add 538g of epichlorohydrin into a 1L reactor, start stirring, control the speed to 200r / min, then add 50g of cyanuric acid and 2.5g of methanol into the reactor in sequence, then heat and control the temperature at 65°C, stir and react for 10h, and carry out synthesis reaction under the condition of excess epichlorohydrin to obtain a synthetic liquid.

[0032] 2. Cool the synthesis liquid to 25°C, add 63 g of sodium methoxide to the synthesis liquid in five batches at a speed of 200 r / min, add 15 g of sodium methoxide to the first batch, react for 20 min, then add 12 g of the second batch of sodium methoxide, and continue to react for 20 min; then add 12 g of the third batch of sodium methoxide, and continue to react for 20 min; then add 12 g of the fourth batch of sodium methoxide, and react for 20 min; adjust the speed to 230 r / min, add 12 g of the fifth batch of sodium methoxide, and continue to react for 20 min to obtain a cyclized liquid.

[0033] 3. Treat the cyclization liquid by a vacuum filtration device to remove solid salts, and then perform vacuum distillation on the filtrate. Stop distillation after the distillation temperature rises to 105°C to obtain a crude product. Then add 400 mL of methanol to recrystallize the crude product. During the recrystallization process, maintain the temperature at -10°C for 2.5 hours. Then perform vacuum filtration for 1 hour to remove the methanol mother liquor to the greatest extent. Dry the solid at 70°C for 5 hours to obtain powdered electronic grade triglycidyl isocyanurate.

[0034] Example 2

[0035] A method for preparing electronic grade triglycidyl isocyanurate, specifically comprising:

[0036] 1. Add 592 g of epichlorohydrin into a 1L reactor, start stirring at a speed of 200 r / min, then add 50 g of cyanuric acid and 5 g of methanol into the reactor in sequence, then heat and control the temperature at 85°C, stir and react for 8 hours, and carry out a synthesis reaction under the condition of excess epichlorohydrin to obtain a synthetic liquid.

[0037] 2. Cool the synthesis liquid to 20°C, rotate at 200r / min, add 63g of sodium methoxide to the synthesis liquid in five batches, add 15g of sodium methoxide to the first batch, and react for 24min; then add 12g of the second batch of sodium methoxide, and continue to react for 24min; when the reaction temperature drops to 20°C, add 12g of the third batch of sodium methoxide, and continue to react for 24min; when the reaction temperature drops to 20°C, add 12g of the fourth batch of sodium methoxide, and react for 24min; adjust the rotation speed to 230r / min, add 12g of the fifth batch of sodium methoxide, and continue to react for 24min. The reaction is completed to obtain a cyclized liquid.

[0038] 3. Treat the cyclization liquid by a vacuum filtration device to remove solid salts, and then perform vacuum distillation on the filtrate. The distillation temperature is raised to 105°C and the distillation is stopped. At this time, a crude product is obtained, and then 400 mL of methanol is added to recrystallize the crude product. The temperature of the recrystallization process is maintained at -10°C for 2.5 hours, and then vacuum filtration is performed for 1 hour to remove the methanol mother liquor to the greatest extent. The solid is dried at 70°C for 5 hours to obtain powdered electronic grade triglycidyl isocyanurate.

[0039] Example 3

[0040] A method for preparing electronic grade triglycidyl isocyanurate, specifically comprising:

[0041] 1. Add 646 g of epichlorohydrin into a 1L reactor, start stirring at a speed of 200 r / min, then add 50 g of cyanuric acid and 7.5 g of methanol into the reactor in sequence, then heat and control the temperature at 110°C, stir and react for 6 hours, and carry out a synthesis reaction under the condition of excess epichlorohydrin to obtain a synthetic liquid.

[0042] 2. Cool the synthesis liquid to 15°C, control the speed at 200r / min, add 63g of sodium methoxide to the synthesis liquid in five batches, add 15g of sodium methoxide in the first batch, react for 30min, then add 12g of the second batch of sodium methoxide, and continue to react for 30min; then add 12g of the third batch of sodium methoxide, and continue to react for 30min; add 12g of the fourth batch of sodium methoxide, and continue to react for 30min; adjust the speed to 230r / min, add 12g of the fifth batch of sodium methoxide, and continue to react for 30min. The reaction is completed to obtain a cyclized liquid.

[0043] 3. Treat the cyclization liquid by a vacuum filtration device to remove solid salts, and then perform vacuum distillation on the filtrate. After the distillation temperature rises to 105°C, the distillation is stopped to obtain a crude product. Then, 400 mL of methanol is added to recrystallize the crude product. The temperature of the recrystallization process is maintained at -10°C and the time is controlled at 2.5 h. Then, vacuum filtration is performed for 1 h to remove the methanol mother liquor to the greatest extent. After the solid is dried at 70°C for 5 h, powdered electronic grade triglycidyl isocyanurate is obtained.

[0044] Comparative Example 1

[0045] 1. Add 538g of epichlorohydrin into a 1L reactor, start stirring at a speed of 200r / min, then add 50g of cyanuric acid and 3g of tetramethylammonium chloride into the reactor in sequence, then heat and control the temperature at 110°C, stir and react for 6h, and carry out a synthesis reaction under the condition of excess epichlorohydrin to obtain a synthetic liquid.

[0046] 2. Cool the synthesis liquid to 25°C, rotate at 200r / min, add 53g of sodium hydroxide to the synthesis liquid in five batches, add 13g of sodium hydroxide in the first batch, and react for 20min; then add 10g of the second batch of sodium hydroxide, and continue to react for 20min; then add 10g of the third batch of sodium hydroxide, and continue to react for 20min; then add 10g of the fourth batch of sodium hydroxide, and react for 20min; adjust the speed to 230r / min, add 10g of the fifth batch of sodium hydroxide, and continue to react for 20min. The reaction is completed to obtain a cyclized liquid.

[0047] 3. Treat the cyclization liquid with a vacuum filtration device to remove solid salts, and then distill the filtrate under reduced pressure. The distillation temperature is raised to 105°C and then the distillation is stopped to obtain a crude product. Then 400 ml of methanol is added to recrystallize the crude product. The temperature of the recrystallization process is maintained at -10°C and the time is controlled at 2.5 hours. Then vacuum filter for about 1 hour to remove the methanol mother liquor to the greatest extent. After the solid is dried at 70°C for 5 hours, powdered electronic grade triglycidyl isocyanurate is obtained.

[0048] Comparative Example 2

[0049] 1. Add 646 g of epichlorohydrin into a 1L reactor, start stirring at a speed of 200 r / min, then add 50 g of cyanuric acid and 5 g of benzyltrimethylammonium chloride into the reactor in sequence, then heat and control the temperature at 65°C, stir and react for 10 hours, and carry out a synthesis reaction under the condition of excess epichlorohydrin to obtain a synthetic liquid.

[0050] 2. Cool the synthesis liquid to 15°C, rotate at 200r / min, add 55g of sodium hydroxide to the synthesis liquid in five batches, add 15g of sodium hydroxide in the first batch, react for 30min; then add 10g of sodium hydroxide in the second batch, continue to react for 30min; then add 10g of sodium hydroxide in the third batch, continue to react for 30min; add 10g of sodium hydroxide in the fourth batch, react for 30min, adjust the rotation speed to 230r / min; add 10g of sodium hydroxide in the fifth batch, continue to react for 30min, and the reaction is completed to obtain a cyclized liquid.

[0051] 3. Treat the cyclization liquid by a vacuum filtration device to remove solid salts, and then perform vacuum distillation on the filtrate. The distillation temperature is raised to 105°C and then the distillation is stopped to obtain a crude product. Then 400 ml of methanol is added to recrystallize the crude product. The temperature of the recrystallization process is maintained at -10°C and the time is controlled at 2.5 hours. Then, vacuum filtration is performed for about 1 hour to remove the methanol mother liquor to the greatest extent. The solid is dried at 70°C for 5 hours to obtain powdered electronic grade triglycidyl isocyanurate.

[0052] The epoxy equivalent, total chlorine equivalent, ECH residue and yield of the powdered electronic grade triglycidyl isocyanurate prepared in Example 1-3 and Comparative Example 1-2 were tested and calculated, and the results are as follows:

[0053]

[0054] Yield Y = W 样 / W 理论值 *100%;

[0055] That is Y=W 样 / 115.12×100%;

[0056] Wherein, Y is the yield, %; W 样 is the actual output of electronic grade triglycidyl isocyanurate, g.

[0057] Unless otherwise specified, all percentages used in the present invention are by mass.

[0058] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing electronic grade triglycidyl isocyanurate, characterized in that: The method consists of the following steps: synthesis reaction, cyclization reaction, and post-treatment; The synthesis reaction comprises adding epichlorohydrin into a reactor, stirring, and then sequentially adding cyanuric acid and methanol, controlling the temperature at 65-110° C., stirring and reacting for 6-10 hours to obtain a synthetic liquid; The cyclization reaction comprises the following steps: cooling the synthesis liquid to 20-25° C., adding sodium methoxide to the synthesis liquid in five batches under stirring, reacting for 20-24 minutes after the first batch of sodium methoxide is added, then adding the second batch of sodium methoxide, and continuing the reaction for 20-24 minutes; then adding the third batch of sodium methoxide, and continuing the reaction for 20-24 minutes; then adding the fourth batch of sodium methoxide, and continuing the reaction for 20-24 minutes; increasing the rotation speed, and then adding the fifth batch of sodium methoxide, and continuing the reaction for 20-24 minutes to obtain a cyclization liquid.

2. The method for preparing electronic grade triglycidyl isocyanurate according to claim 1, characterized in that: In the synthesis reaction, the weight ratio of epichlorohydrin, cyanuric acid and methanol is 538-646:50:2.5-7.

5.

3. The method for preparing electronic grade triglycidyl isocyanurate according to claim 1, characterized in that: In the cyclization reaction, the weight ratio of the first batch of sodium methoxide, the second batch of sodium methoxide, the third batch of sodium methoxide, the fourth batch of sodium methoxide, and the fifth batch of sodium methoxide is 15:12:12:12:

12.

4. The method for preparing electronic grade triglycidyl isocyanurate according to claim 1, characterized in that: The weight ratio of cyanuric acid in the synthesis reaction to the total weight of the five batches of sodium methoxide in the cyclization reaction was 50:

63.

5. The method for preparing electronic grade triglycidyl isocyanurate according to claim 1, characterized in that: The post-treatment is to treat the cyclized liquid by a vacuum filtration device, then decompress the filtrate, stop the distillation after the distillation temperature rises to 105°C, then add methanol to recrystallize the crude product, vacuum filter, and dry the solid to obtain triglycidyl isocyanurate.

6. The method for preparing electronic grade triglycidyl isocyanurate according to claim 5, characterized in that: The weight-to-volume ratio of the cyanuric acid in the synthesis reaction to the total weight of the methanol in the post-treatment is 50 g:400 mL.

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