Synthesis method of trimethylolpropane tri (methyl) acrylate

Abstract

The invention relates to the technical field of chemical reaction, in particular to a synthesis method of trimethylolpropane tri (methyl) acrylate, which comprises the following steps: adding TMP (trimethylolpropane) produced in a workshop into acrylic acid, adding a certain amount of entrainer, polymerization inhibitor and catalyst, stirring and heating until reaction reflux, setting reaction time, and after the reaction is finished, cooling to room temperature to obtain the trimethylolpropane tri (methyl) acrylate. And sequentially washing and extracting with distilled water and dilute alkali liquor, and evaporating and concentrating to obtain the product. The method has the beneficial effects that the use of methanesulfonic acid can be replaced or reduced from the source, the quality of the byproduct sodium polyacrylate is improved, the content of the produced trimethylolpropane tri (methyl) acrylate can reach 82% or above, the viscosity of the cone plate can reach 70-120mpa. S, and the yield is high. And meanwhile, sufficient stirring, scraping, dismounting and cleaning can be conveniently carried out according to use requirements, residues are not likely to be caused, and follow-up use is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of chemical reactions, in particular to a method for synthesizing trimethylolpropane tri(meth)acrylate. Background Art

[0002] With the rapid development of radiation curing technology, the application fields of polyol acrylate series products are becoming wider and wider. It has a wide range of uses in many fields such as light-curing coatings, oil black and polymer modification and crosslinking agents. Among them, the representative ones are: trimethylolpropane tripropionate (TMPTA), pentaerythritol triacrylate (PETA), pentaerythritol diacrylate (NPGDA), tripropylene glycol diacrylate (TPGDA), etc. Among them, trimethylolpropane tri(meth)acrylate (TMPTA) can be used as a comonomer to synthesize special acrylic resins, and can also be used as a crosslinking agent for rubber and plastics. Due to the characteristics of high double bond content, fast curing speed, low viscosity, high boiling point, and low volatility, TMPTA has become the most widely used and largest-volume multifunctional acrylate active crosslinking diluent in the field of radiation curing.

[0003] In industry, trimethylolpropane tri(meth)acrylate is mostly synthesized by direct esterification reaction, which makes the reaction smoother and faster. Organic or inorganic strong acids are often used as catalysts, and the process is mature. However, the removal of strong acid catalysts will not only lead to the discharge of a large amount of wastewater, but also cause the production of a variety of by-products. The catalyst methylsulfonic acid used in the workshop acrylate cannot be separated separately during the post-treatment process, and eventually exists in the sodium polyacrylate by-product, reducing its product quality. On the basis of not affecting the product quality and yield, try to improve the process, replace or reduce the use of methylsulfonic acid from the source, and improve the quality of the by-product sodium polyacrylate;

[0004] In this regard, China's patent application number: 202311588343.X discloses a method for synthesizing trimethylolpropane methacrylate, wherein the trihydroxy light / heavy component by-products produced in the process of producing trimethylolpropane methacrylate by esterification reaction in the workshop are added to acrylic acid, a certain amount of entrainer, inhibitor and catalyst are added, the mixture is stirred and heated to the reaction reflux, the reaction time is set, and after the reaction is completed, the mixture is washed and extracted with distilled water and dilute alkali solution in turn, and the trimethylolpropane methacrylate product is obtained by evaporation and concentration;

[0005] However, the existing synthesis method and device are not convenient to replace or reduce the use of methanesulfonic acid at the source, which affects the quality of the by-product sodium polyacrylate, and is not convenient to fully stir, scrape and disassemble and clean according to the needs of use, which is easy to cause residues and affect subsequent use;

[0006] Therefore, in order to solve the above problems, a method for synthesizing trimethylolpropane tri(meth)acrylate is proposed. Summary of the invention

[0007] The object of the present invention is to provide a method for synthesizing trimethylolpropane tri(meth)acrylate, so as to solve the problem that the existing synthesis method and device proposed in the above background technology are inconvenient to replace or reduce the use of methyl sulfonic acid at the source, which affects the quality of the by-product sodium polyacrylate, and is inconvenient to fully stir, scrape and disassemble and clean according to the needs of use, which easily causes residues that affect subsequent use.

[0008] To achieve the above object, the present invention provides the following technical scheme: a method for synthesizing trimethylolpropane tri(meth)acrylate, comprising a reactor, the top of which is covered with a top cover, and the top of which is equipped with a condensation component, a temperature detection component, a feeding pipe, an upper solenoid valve, a pressure component and a spare notch, the reactor is equipped with a stirring component through an inner rotating shaft, and the reactor is also equipped with a scraping and stirring component through an inner rotating drum, and the reactor is equipped with a heating component outside, and further comprising the following steps:

[0009] S1, add trimethylolpropane solution and acrylic acid into a reactor, then add entrainer, inhibitor and catalyst, and mix well;

[0010] S2, stirring by a stirring component and a scraping component, and heating to 90-95° C. by a heating component;

[0011] S3, wait for the reaction to start reflux, and keep the reaction warm for 14 hours;

[0012] S4. When the reaction water is close to the theoretical value, sampling begins. According to the acidity of the reaction solution, sampling is performed every 1 or 2 hours until the acidity is less than 5% (calculated in AA), which is regarded as the end point of the reaction.

[0013] S5, after the reaction is completed, wash with water and alkali until the water phase becomes weakly alkaline;

[0014] S6, vacuum dealkylation and concentration to a product content of 30-40%, the dehydration temperature is controlled at 50-80°C, and the acrylate product is obtained.

[0015] As a further embodiment of the present invention, specifically, the trimethylolpropane solution in S1 is trimethylolpropane (TMP) produced in a workshop, the entrainer accounts for 25.5-26.5% of the solution mass ratio, the entrainer in S1 includes one or more of cyclohexane and toluene, etc., the inhibitor in S1 includes a mixed system of hydroquinone and p-hydroxyanisole, and the catalyst in S1 includes one or more of ionic liquids and methanesulfonic acid, etc.

[0016] As a further embodiment of the present invention, the bottom support of the reactor is equipped with a bottom support plate, the bottom of the bottom support plate is equipped with a lower support plate, and the bottom of the lower support plate supports a lower mounting plate, the side of the lower mounting plate supports a support frame, and the upper part of the support frame is equipped with a lower support plate, the surface of the lower support plate is equipped with a servo motor, the output end of the servo motor is equipped with a reducer, the output end of the reducer is connected to the lower end of the inner rotating shaft through a coupling for transmission, the inner rotating cylinder is assembled on the outside of the inner rotating shaft through a bearing set, the outside of the inner rotating cylinder is assembled in the reactor through a bearing second insertion arrangement, and a corresponding inner convex cover shell is integrally fixed in the center of the interior of the reactor, the space between the inner convex cover shell and the upper part of the inner rotating cylinder is filled with a second rotating sleeve gasket, and the space between the inner rotating cylinder and the upper part of the inner rotating shaft is filled with a first rotating sleeve gasket.

[0017] As a further embodiment of the present invention, the lower end of the inner drum is supported and assembled in the center of the bottom of the reactor by a support plate with a bearing, and the lower end of the inner drum is assembled in the lower mounting plate through an inner bearing and extends downward, a transmission wheel is fixedly provided at the lower end of the inner shaft, a driven wheel is connected to the rear side of the transmission wheel through a belt sleeve, a driven shaft is fixedly provided inside the driven wheel, the upper end of the driven shaft is assembled in the lower mounting plate through a bearing, and the lower end of the driven shaft is supported and assembled with a bearing with a seat, a transmission gear is fixedly provided on the upper part of the driven shaft, a driven gear is meshed with the front side of the transmission gear, and the driven gear is fixed to the outer wall of the lower end of the inner drum.

[0018] As a further embodiment of the present invention, the stirring assembly includes three groups of stirring frames, an upper sleeve is fixedly provided at the upper center of the stirring frame, the upper sleeve is assembled on the upper end of the inner rotating shaft and fixed by screws, the stirring frames are evenly distributed in a triangular shape inside the reactor, and stirring rods are staggered on the outer wall of the stirring frame.

[0019] As a further embodiment of the present invention, the scraping and stirring assembly includes an inner scraper arm, a lower scraper arm and an outer scraper arm. The inner side of the inner scraper arm is close to the inner wall of the inner convex cover shell. The lower scraper arm is integrally fixed to the bottom of the inner scraper arm, and the bottom wall of the lower scraper arm is close to the bottom wall of the reactor. The outer scraper arm is integrally fixed to the side of the inner scraper arm, and the side wall of the outer scraper arm is close to the inner wall of the reactor. An inner sleeve is integrally fixed to the center of the upper part of the inner scraper arm. The inner sleeve is mounted on the upper part of the inner rotating drum and assembled by screws. The upper support of the outer scraper arm is equipped with an upper support ring, and the upper support ring surrounds the outer side of the upper part of the stirring assembly.

[0020] As a further feature of this solution, the bottom side of the reactor is arranged with an arc-shaped depression, and a drainage groove is provided at the bottom of the side of the reactor, and a lower solenoid valve corresponding to the drainage groove is fixedly provided at the bottom of the reactor, and a lower liquid pipe is installed at the bottom of the lower solenoid valve.

[0021] As a further embodiment of the present invention, the heating component is surrounded and assembled on the outer wall of the reactor, an outer cover shell is provided on the outside of the heating component, and the outer cover shell is assembled with the reactor upper and lower parts by bolts, and the heating component is divided into two halves to form a cylindrical sleeve arranged on the outside of the heating component, and an inner insulation shell is fixed on the inner wall of the outer cover shell.

[0022] As a further feature of the present invention, the outer cover shell is wrapped with outer cover cotton, a rubber hoop is sleeved on the outer surface of the outer cover cotton, and a limiting slot corresponding to the rubber hoop is opened on the outer wall of the outer cover cotton, and the outer cover cotton is composed of sixteen equally divided pieces to form a cylindrical shape.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Through the corresponding feeding, reaction process and control, the use of methyl sulfonic acid can be replaced or reduced from the source, and the quality of the by-product sodium polyacrylate can be improved. The ester content of the produced trimethylolpropane tri(meth)acrylate can reach more than 82%, and the cone-plate viscosity can reach 70-120mpa·s, which is beneficial to the synthesis of trimethylolpropane methacrylate;

[0025] 2. By arranging a stirring assembly, an inner rotating shaft, a scraping assembly and an inner rotating drum, it is convenient to synchronously drive the inner rotating shaft and the inner rotating drum to rotate, and the rotation directions are opposite under the cooperation of the servo motor, and then the corresponding stirring assembly and scraping assembly are driven to stir and scrape the inner wall of the reactor, so that the stirring is uniform without causing residue, making the mixing and stirring of the raw materials more convenient, and also convenient for subsequent cleaning, which is beneficial to the synthesis of trimethylolpropane methacrylate;

[0026] 3. By setting a heating component, it is convenient to heat the outside of the reactor, so as to provide heat supply to the inside. Under the setting of the outer cover shell and the outer cover cotton, it is convenient to insulate and keep warm, making the internal reaction more convenient and stable, making the operation more convenient and efficient, and being conducive to the synthesis of trimethylolpropane methacrylate;

[0027] 4. While designing the above structure, the reaction kettle, the top cover, the bottom support plate and the lower support plate are assembled, and the rubber sleeve is limited, so that the assembly operation is more convenient, and it is also easy to disassemble, so that the cleaning operation is more convenient, the use is more convenient and quick, and it is not easy to produce residue, which is beneficial to the synthesis of trimethylolpropane methacrylate. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a front view stereoscopic schematic diagram of the overall structure of the present invention;

[0030] Figure 2 It is a side cross-sectional perspective schematic diagram of the local structure of the reactor of the present invention;

[0031] Figure 3 It is a bottom-up stereoscopic schematic diagram of the overall structure of the present invention;

[0032] Figure 4 It is a top perspective schematic diagram of the local structure of the reactor of the present invention;

[0033] Figure 5 It is a top view cross-sectional perspective schematic diagram of the structure of the present invention;

[0034] Figure 6 It is a side perspective schematic diagram of the transmission structure of the present invention;

[0035] Figure 7 It is a frontal three-dimensional assembly exploded view of the local structure of the reactor of the present invention;

[0036] Figure 8 For the present invention Figure 2 A schematic diagram of the enlarged structure in the middle.

[0037] Fig. 9 For the present invention Figure 2 Enlarged schematic diagram of the structure at point B in the middle.

[0038] In the figure: 100, reactor; 101, inner convex cover; 102, drain tank; 103, lower solenoid valve; 104, lower liquid pipe; 110, top cover; 111, condensation component; 112, temperature detection component; 113, feeding pipe; 114, upper solenoid valve; 115, pressure component; 116, spare notch; 120, bottom support plate; 130, lower support plate; 131, lower mounting plate; 132, support frame; 133, lower support plate; 140, stirring component; 141, stirring frame; 142, upper mounting sleeve; 143, stirring rod; 150, inner rotating shaft; 151, bearing 1; 152, rotating sleeve pad 1; 153 , bearing support plate; 160, scraping and stirring assembly; 161, inner scraping arm; 162, lower scraping arm; 163, outer scraping arm; 164, inner sleeve; 165, upper support ring; 170, inner drum; 171, bearing 2; 172, rotating sleeve pad 2; 180, servo motor; 181, reducer; 182, transmission wheel; 183, belt; 184, driven wheel; 185, driven shaft; 186, transmission gear; 187, driven gear; 188, seat bearing; 190, heating assembly; 191, outer cover shell; 192, inner insulation shell; 193, outer cover cotton; 194, rubber hoop; 195, limit slot. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] See also Figure 1-Figure 9 The present invention provides an embodiment: a method for synthesizing trimethylolpropane tri(meth)acrylate, comprising a reactor 100, a top cover 110 is provided on the top of the reactor 100, and a condensation component 111, a temperature detection component 112, a feeding pipe 113, an upper solenoid valve 114, a pressure component 115 and a spare notch 116 are installed on the top of the top cover 110, a stirring component 140 is installed inside the reactor 100 through an inner rotating shaft 150, and a scraping and stirring component 160 is also installed inside the reactor 100 through an inner rotating drum 170, and a heating component 190 is installed outside the reactor 100, and the following steps are also included:

[0041] S1, adding trimethylolpropane solution and acrylic acid into the reaction kettle 100, and then adding an azeotropic agent, an inhibitor and a catalyst, and mixing them evenly;

[0042] S2, stirring by the stirring component 140 and the scraping component 160, and heating to 90-95° C. by the heating component 190;

[0043] S3, wait for the reaction to start reflux, and keep the reaction warm for 14 hours;

[0044] S4. When the reaction water is close to the theoretical value, sampling begins. According to the acidity of the reaction solution, sampling is performed every 1 or 2 hours until the acidity is less than 5% (calculated in AA), which is regarded as the end point of the reaction.

[0045] S5, after the reaction is completed, wash with water and alkali until the water phase becomes weakly alkaline;

[0046] S6, vacuum dealkylation and concentration until the product content is 30-40%, the dehydration temperature is controlled at 50-80°C, and the acrylate finished product is obtained;

[0047] As more detailed in this embodiment, specifically, the trimethylolpropane solution in S1 is trimethylolpropane (TMP) produced in a workshop, the entrainer accounts for 25.5-26.5% of the solution mass ratio, the entrainer in S1 includes one or more of cyclohexane and toluene, etc., the inhibitor in S1 includes a mixed system of hydroquinone and p-hydroxyanisole, and the catalyst in S1 includes one or more of ionic liquids and methanesulfonic acid, etc.;

[0048] As a more detailed example of the present embodiment, the bottom side of the reactor 100 is arranged in an arc-shaped concave configuration, and a drainage groove 102 is provided at the bottom of the side of the reactor 100, and a lower solenoid valve 103 corresponding to the drainage groove 102 is fixedly provided at the bottom of the reactor 100, and a lower liquid pipe 104 is installed at the bottom of the lower solenoid valve 103, so as to facilitate the control of discharging and discharging of materials, and the bottom support of the reactor 100 is equipped with a bottom supporting plate 120, and a lower supporting plate 130 is installed at the bottom of the bottom supporting plate 120, and a lower mounting plate 131 is supported at the bottom of the lower mounting plate 131, and a supporting frame 132 is supported on the side of the lower mounting plate 131, and a lower supporting plate 133 is installed on the upper part of the supporting frame 132. In this way, it is convenient to support and assemble the reactor 100. A servo motor 180 is mounted on the surface of the lower support plate 133. A reducer 181 is mounted on the output end of the servo motor 180. The output end of the reducer 181 is connected to the lower end of the inner shaft 150 through a coupling for transmission. The inner drum 170 is mounted on the outside of the inner shaft 150 through a bearing 151. The outside of the inner drum 170 is mounted inside the reactor 100 through a bearing 2 171. A corresponding inner convex cover shell 101 is integrally fixed in the center of the reactor 100. A rotating sleeve 2 172 is filled between the inner convex cover shell 101 and the upper part of the inner drum 170. A rotating sleeve pad 152 is filled between 170 and the upper part of the inner rotating shaft 150. The lower end of the inner rotating drum 170 is supported and assembled in the center of the bottom of the reactor 100 through a bearing support plate 153, and the lower end of the inner rotating drum 170 is inserted and assembled in the lower mounting plate 131 through an inner bearing and extends to the bottom. A transmission wheel 182 is fixed at the lower end of the inner rotating shaft 150, and a driven wheel 184 is sleeved and connected to the rear side of the transmission wheel 182 through a belt 183. A driven shaft 185 is fixed inside the driven wheel 184. The upper end of the driven shaft 185 is inserted and assembled in the lower mounting plate 131 through a bearing, and the lower end of the driven shaft 185 is supported and assembled with a seat bearing 18 8. A transmission gear 186 is fixedly arranged on the upper part of the driven shaft 185, and a driven gear 187 is meshed with the front side of the transmission gear 186. The driven gear 187 is fixed to the outer wall of the lower end of the inner drum 170. During operation, the inner shaft 150 and the inner drum 170 rotate in opposite directions through the intermediate drive of the driven shaft 185, making subsequent operations more convenient and efficient. During assembly, the transmission is more stable and convenient through the cooperation of the bearing 1 151 and the bearing 2 171. Under the cooperation of the rotating sleeve pad 152 and the rotating sleeve pad 2 172, the interior of the reactor 100 is relatively closed during rotation, making it more convenient to use.

[0049] As a more detailed description of the present embodiment, the stirring assembly 140 includes three groups of stirring frames 141, an upper sleeve 142 is fixedly provided at the center of the upper part of the stirring frame 141, and the upper sleeve 142 is mounted on the upper end of the inner rotating shaft 150 and fixed by screws. The stirring frames 141 are evenly distributed inside the reactor 100 in a triangular shape, and stirring rods 143 are staggered on the outer wall of the stirring frame 141, so as to facilitate the assembly of the stirring assembly 140 during assembly, so that the stirring is more uniform and sufficient. The scraping and stirring assembly 160 includes an inner scraping arm 161, a lower scraping arm 162 and an outer scraping arm 163. The inner side of the inner scraping arm 161 is close to the inner wall of the inner convex cover shell 101, and the lower scraping arm 162 is integrally fixed to the inner scraping arm 1 61, and the bottom wall of the lower scraper arm 162 is close to the bottom wall of the reactor 100, the outer scraper arm 163 is integrally fixed to the side of the inner scraper arm 161, and the side wall of the outer scraper arm 163 is close to the inner wall of the reactor 100, and the inner sleeve 164 is integrally fixed to the center of the upper part of the inner scraper arm 161, the inner sleeve 164 is sleeved and assembled on the upper part of the inner rotating cylinder 170 and assembled by screws, the upper support ring 165 is assembled on the upper part of the outer scraper arm 163, and the upper support ring 165 surrounds the outer side of the upper part of the stirring component 140, so that it will not cause movement interference with the stirring component 140 during assembly, so that the stirring component 140 and the scraping component 160 are easy to be driven and rotated synchronously, making stirring and scraping the inner wall more convenient and efficient.

[0050] As a more detailed example of this embodiment, the heating component 190 is surrounded and assembled on the outer wall of the reactor 100, and the outer cover shell 191 is provided on the outside of the heating component 190, and the outer cover shell 191 is assembled with the reactor 100 by bolts, and the heating component 190 is enclosed in two halves to form a cylindrical sleeve on the outside of the heating component 190, and the inner wall of the outer cover shell 191 is fixed with an inner heat insulation shell 192, and the outer cover shell 191 is wrapped and assembled with an outer cover cotton 193, and the outer cover cotton 193 is provided with a rubber hoop 194, and the outer wall of the outer cover cotton 193 is provided with a corresponding rubber hoop 194. The limiting card slot 195 is formed by the outer cotton 193, which is composed of sixteen equally divided pieces to form a cylindrical shape. Therefore, when in use, the heating component 190 is connected to the corresponding control module for control, so that the inside of the reactor 100 is heated by the heating component 190, and then auxiliary monitoring is performed with the cooperation of the temperature detection component 112. Then, the outer cover shell 191 and the inner heat insulation shell 192 are relatively isolated, and the outer cotton 193 and the rubber hoop 194 are cooperated to keep warm while not easily causing burns on the outside, making it safer and more convenient to use;

[0051] When in use, the electronic control component elements and sensing components are connected to the corresponding power distribution and control modules for connection and control. The specific connection structure and use principle belong to the prior art and are common knowledge to those skilled in the art. They can be implemented through a variety of implementation methods, and no other special requirements are made in this application. It is only necessary that they can realize the functions described in this application, so no specific limitations are made here.

[0052] Embodiment 1:

[0053] TMP, acrylic acid, azeotroping agent and polymerization inhibitor are added to the reactor 100 in sequence, and then 100% of the ionic liquid catalyst is added, and the stirring component 140 and the scraping component 160 are stirred. Under the heating of the heating component 190, the reaction reflux is reached, and the reaction temperature is set to 90°C and the reaction time is 14h. During the reaction, there is no need to pass air into the reactor 100. The acidity of the reaction liquid is measured to be 4.94, and the reaction is completed. The product is washed twice at 60°C, washed twice with alkali at 40°C, and washed once at 60°C. Vacuum dehydration is performed to a product content of 35.0%, and the dehydration temperature is 58°C. The acrylate content produced reaches more than 82%, and the cone-plate viscosity can reach 80mpa·s.

[0054] Embodiment 2:

[0055] TMP, acrylic acid, azeotroping agent and polymerization inhibitor are added to the reactor 100 in sequence, and then 75% of the ionic liquid catalyst is added, and the mixture is stirred by the stirring assembly 140 and the scraping assembly 160. Under the heating of the heating assembly 190, the mixture is refluxed to the reaction, and the reaction temperature is set to 90°C and the reaction time is 14h. During the reaction, it is not necessary to pass air into the reactor 100. The acidity of the reaction liquid is measured to be 4.33, and the reaction is completed. The product is washed twice at 60°C, washed twice with alkali at 40°C, and washed once at 60°C. Vacuum dehydration is performed to a product content of 35.0%, and the dehydration temperature is 58°C. The acrylate content produced reaches more than 82%, and the cone-plate viscosity can reach 74mpa·s.

[0056] Embodiment 3:

[0057] TMP, acrylic acid, azeotroping agent and polymerization inhibitor are added to the reactor 100 in sequence, and then 50% of the ionic liquid catalyst is added, and the mixture is stirred by the stirring component 140 and the scraping component 160. Under the heating of the heating component 190, the mixture is refluxed to the reaction, and the reaction temperature is set to 90°C and the reaction time is 14h. During the reaction, it is not necessary to pass air into the reactor 100. The acidity of the reaction liquid is measured to be 4.72, and the reaction is completed. The product is washed twice at 60°C, washed twice with alkali at 40°C, and washed once at 60°C. Vacuum dehydration is performed to a product content of 35.0%, and the dehydration temperature is 58°C. The acrylate content produced reaches more than 82%, and the cone-plate viscosity can reach 96mpa·s.

[0058] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any ordinary technician in the industry can smoothly implement the present invention as shown in the drawings and described above. However, any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A method for synthesizing trimethylolpropane tri(meth)acrylate, comprising a reaction kettle (100), wherein the top cover of the reaction kettle (100) is provided with a top cover (110), and the top of the top cover (110) is equipped with a condensation component (111), a temperature detection component (112), a feeding pipe (113), an upper solenoid valve (114), a pressure component (115) and a spare notch (116), the inside of the reaction kettle (100) is equipped with a stirring component (140) through an inner rotating shaft (150), and the inside of the reaction kettle (100) is also equipped with a scraping and stirring component (160) through an inner rotating drum (170), and the outside of the reaction kettle (100) is equipped with a heating component (190), characterized in that: The following steps are involved: S1, adding trimethylolpropane solution and acrylic acid into a reaction kettle (100), and then adding an azeotropic agent, a polymerization inhibitor and a catalyst, and mixing them uniformly; S2, stirring the mixture by means of a stirring assembly (140) and a scraping assembly (160), and heating the mixture to 90-95° C. by means of a heating assembly (190); S3, wait for the reaction to start reflux, and keep the reaction warm for 14 hours; S4. When the reaction water is close to the theoretical value, sampling begins. According to the acidity of the reaction solution, sampling is performed every 1 or 2 hours until the acidity is less than 5% (calculated in AA), which is regarded as the end point of the reaction. S5, after the reaction is completed, wash with water and alkali until the water phase becomes weakly alkaline; S6, vacuum dealkylation and concentration to a product content of 30-40%, the dehydration temperature is controlled at 50-80°C, and the acrylate product is obtained.

2. The method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 1, characterized in that: Specifically, the trimethylolpropane solution described in S1 is trimethylolpropane (TMP) produced in a workshop, the entrainer accounts for 25.5-26.5% of the solution mass ratio, the entrainer described in S1 includes one or more of cyclohexane and toluene, etc., the inhibitor described in S1 includes a mixed system of hydroquinone and p-hydroxyanisole, and the catalyst described in S1 includes one or more of ionic liquids and methanesulfonic acid, etc.

3. The method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 1, characterized in that: The bottom support of the reaction kettle (100) is equipped with a bottom support plate (120), the bottom of the bottom support plate (120) is equipped with a lower support plate (130), and the bottom of the lower support plate (130) supports a lower mounting plate (131), the side of the lower mounting plate (131) is supported by a support frame (132), and the upper part of the support frame (132) is equipped with a lower support plate (133), the surface of the lower support plate (133) is equipped with a servo motor (180), the output end of the servo motor (180) is equipped with a reducer (181), and the output end of the reducer (181) is connected to the inner rotating shaft (15 0) is connected for transmission at the lower end through a coupling, the inner drum (170) is sleeved and assembled on the outside of the inner rotating shaft (150) through a bearing 1 (151), the outside of the inner drum (170) is inserted and assembled in the interior of the reaction kettle (100) through a bearing 2 (171), and a corresponding inner convex cover shell (101) is integrally fixed in the center of the interior of the reaction kettle (100), a rotating sleeve gasket 2 (172) is filled between the inner convex cover shell (101) and the upper part of the inner drum (170), and a rotating sleeve gasket 1 (152) is filled between the inner drum (170) and the upper part of the inner rotating shaft (150).

4. A method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 3, characterized in that: The lower end of the inner rotating drum (170) is supported and assembled at the center of the bottom of the reaction kettle (100) through a bearing support plate (153), and the lower end of the inner rotating drum (170) is inserted and assembled inside the lower mounting plate (131) through an inner bearing and extends downward. A transmission wheel (182) is fixedly arranged at the lower end of the inner rotating shaft (150), and a driven wheel (184) is sleeved and connected to the rear side of the transmission wheel (182) through a belt (183). The driven wheel (184) A driven shaft (185) is fixedly arranged inside, the upper end of the driven shaft (185) is assembled inside the lower mounting plate (131) through a bearing insertion arrangement, and the lower end of the driven shaft (185) is supported and assembled with a seat bearing (188), a transmission gear (186) is fixedly arranged on the upper part of the driven shaft (185), a driven gear (187) is meshed with the front side of the transmission gear (186), and the driven gear (187) is fixed to the outer wall of the lower end of the inner rotating drum (170).

5. The method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 3, characterized in that: The stirring assembly (140) comprises three groups of stirring racks (141), an upper sleeve (142) is fixedly arranged at the center of the upper part of the stirring rack (141), the upper sleeve (142) is sleeved and assembled on the upper end of the inner rotating shaft (150) and fixed by screws, the stirring racks (141) are evenly distributed in a triangular shape inside the reaction kettle (100), and stirring rods (143) are staggeredly arranged on the outer wall of the stirring rack (141).

6. The method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 3, characterized in that: The scraping and stirring assembly (160) comprises an inner scraping arm (161), a lower scraping arm (162) and an outer scraping arm (163); the inner side of the inner scraping arm (161) is close to the inner wall of the inner convex cover shell (101); the lower scraping arm (162) is integrally fixed to the bottom of the inner scraping arm (161); and the bottom wall of the lower scraping arm (162) is close to the bottom wall of the reaction kettle (100); the outer scraping arm (163) is integrally fixed to the inner scraping arm (161). The side wall of the outer scraper arm (163) is close to the inner wall of the reaction kettle (100), and an inner sleeve (164) is integrally fixedly provided at the center of the upper part of the inner scraper arm (161), and the inner sleeve (164) is sleeved and mounted on the upper part of the inner rotating drum (170) and assembled by screws, and the upper support ring (165) is mounted on the upper support of the outer scraper arm (163), and the upper support ring (165) surrounds the outer side of the upper part of the stirring assembly (140).

7. The method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 3, characterized in that: The bottom side of the reactor (100) is arranged in an arc-shaped concave shape, and a drainage groove (102) is provided at the bottom of the side of the reactor (100). A lower solenoid valve (103) corresponding to the drainage groove (102) is fixedly provided at the bottom of the reactor (100), and a lower liquid pipe (104) is installed at the bottom of the lower solenoid valve (103).

8. The method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 3, characterized in that: The heating component (190) is mounted on the outer wall of the reaction kettle (100), and an outer cover shell (191) is provided on the outside of the heating component (190). The outer cover shell (191) is assembled with the reaction kettle (100) by bolts, and the heating component (190) is formed of two halves that are enclosed together to form a cylindrical sleeve on the outside of the heating component (190). An inner heat-insulating shell (192) is fixed on the inner wall of the outer cover shell (191).

9. The method for synthesizing trimethylolpropane tri(meth)acrylate according to claim 8, characterized in that: The outer cover shell (191) is wrapped with an outer cover cotton (193) on the outside, and a rubber hoop (194) is sleeved on the outside of the outer cover cotton (193). The outer wall of the outer cover cotton (193) is provided with a limit slot (195) corresponding to the rubber hoop (194). The outer cover cotton (193) is composed of sixteen equally divided pieces and forms a cylindrical shape.

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