Device for preparing polysiloxane

Abstract

The utility model discloses a device for preparing polysiloxane. The device mainly comprises a raw material tank, a reaction tank and a product tank, the raw material tank is communicated with the reaction tank, the reaction tank is communicated with the product tank, a catalyst placing box is arranged in the reaction tank, and the solid acid catalyst prepared by the preparation method is placed in the catalyst placing box. When the device is used for preparing polysiloxane, the content of target components in low-molecular-weight polysiloxane can be increased.

Description

Technical Field

[0001] This utility model relates to the field of organosilicon technology, specifically, to an apparatus for preparing polysiloxanes. Background Technology

[0002] High-resilience polyurethane foam is widely used in mattresses, furniture cushions, and car seats due to its excellent physical and mechanical properties and extremely high resilience. The performance of high-resilience polyurethane foam largely depends on the structure of its internal cells. Polydimethylsiloxane can influence the size, shape, and distribution of the cells. It not only promotes cell refinement, making the foam denser and thus improving its strength and resilience, but also adjusts the cell size, improving its air permeability.

[0003] Currently, the synthesis methods for low molecular weight polydimethylsiloxanes are mainly based on the use of sulfuric acid, ion exchange resins and other catalysts. However, the preparation process is complex and cumbersome, and it is easy to generate solid or liquid waste. Moreover, the content of effective components in the prepared polydimethylsiloxanes is relatively low.

[0004] In view of this, this utility model is proposed. Utility Model Content

[0005] The purpose of this invention is to overcome the defects of the prior art and provide an apparatus for preparing polysiloxanes.

[0006] This utility model also provides an apparatus for preparing polysiloxane, which mainly includes: a raw material tank, a reaction tank and a product tank. The raw material tank is connected to the reaction tank and the reaction tank is connected to the product tank. A catalyst placement box is provided inside the reaction tank, and the solid acid catalyst prepared by the above preparation method is placed inside the catalyst placement box.

[0007] This utility model has the following beneficial effects:

[0008] This invention provides an apparatus for preparing polysiloxanes and a method for preparing a solid acid catalyst, which mainly includes a raw material tank, a reaction tank, and a product tank. The raw material tank is connected to the reaction tank, and the reaction tank is connected to the product tank. A catalyst placement box is provided inside the reaction tank, containing the solid acid catalyst prepared by the above-described method. This apparatus can more effectively improve the reaction efficiency of the raw materials, and the product can achieve solid-liquid separation without further processing, achieving a green and environmentally friendly effect. Attached Figure Description

[0009] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 The apparatus for preparing polysiloxanes is shown in the attached drawings, numbered as follows: 1-1-Raw material tank; 1-2-First valve; 1-3-First temperature sensor; 1-4-First heating layer; 1-5-Feed port; 1-6-Electric stirring mechanism; 1-7-Feed pump; 2-1 Reactor; 2-2 Filter screen; 2-3-Baffle; 2-4-Catalyst placement box; 2-5-Second heating layer; 2-6-Second temperature sensor; 2-7-Second valve; 3-1 Product tank; 3-2-Third valve; 3-3-Filter;

[0011] Figure 2 Top view of the assembleable catalyst box;

[0012] Figure 3 This is an enlarged view of the assembleable catalyst box. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0014] The primary objective of this invention is to provide a solid acid catalyst and its preparation method, which is suitable for preparing low molecular weight polysiloxanes.

[0015] The second objective of this invention is to provide an apparatus for preparing polysiloxanes.

[0016] The third objective of this invention is to provide a method for improving the preparation of target components in low molecular weight polysiloxanes.

[0017] The fourth objective of this invention is to provide a method for preparing high-resilience polyurethane foam.

[0018] The following is a detailed description of a solid acid catalyst and an apparatus and method for preparing polysiloxanes provided by embodiments of this utility model.

[0019] In a first aspect, the present invention provides a method for preparing a solid acid catalyst, which includes: granulating and calcining acid-leached mesoporous zirconium phosphate powder, followed by acid leaching again to obtain a solid acid catalyst.

[0020] This invention provides a method for preparing a solid acid catalyst based on the following characteristics of zirconium phosphate: Zirconium phosphate is a novel multifunctional mesoporous material and one of the layered solid acid materials. It possesses a large specific surface area and surface charge, making it a strong solid acid with excellent ion exchange properties. Zirconium phosphate exhibits the common characteristics of layered compounds, high chemical stability, and possesses both ion exchange performance similar to ion exchange resins and shape-selective adsorption and catalytic performance similar to zeolites. It also exhibits high thermal stability and acid and alkali resistance. After acid leaching the mesoporous zirconium phosphate powder, it can adsorb and carry some acid. Subsequent granulation and calcination treatments can improve the compressive strength and specific surface area of ​​the shaped material. A second acid leaching allows for further adsorption and carrying of a large amount of acidic substances, further enhancing the catalytic performance of the solid acid catalyst.

[0021] In some optional embodiments, the preparation method of the solid acid catalyst includes: acid leaching and drying mesoporous zirconium phosphate powder, mixing and extruding it with auxiliary materials, and then calcining it to obtain calcined material; and acid leaching and drying the calcined material again to obtain the solid acid catalyst.

[0022] Preferably, the method includes the following steps: first impregnating mesoporous zirconium phosphate powder in an acidic solution, and drying it after impregnation to obtain acidified mesoporous zirconium phosphate powder; mixing the acidified mesoporous zirconium phosphate powder with starch, guar gum powder, glycerol, glass fiber and water evenly and then extruding it into granules; calcining the obtained shaped granules to obtain calcined material; and second impregnating the calcined material in an acidic solution, and drying it after impregnation to obtain a solid acid catalyst.

[0023] Preferably, during the first acid impregnation, the weight ratio of mesoporous zirconium phosphate powder to acid solution is 1:10-1:20, and the acid used for the first impregnation includes at least one of hydrochloric acid, sulfuric acid, carborane acid, and trifluoromethanesulfonic acid; the concentration of the acid solution is 50-100%; the impregnation temperature is 25-35℃, and the time is 10-15h; the drying temperature is 60-140℃, and the time is 8-12h.

[0024] Preferably, the weight ratio of acidified mesoporous zirconium phosphate powder to starch, guar gum powder, glycerol, glass fiber and water is 100:1-10:1-20:1-20:1-20:1-50, the extruded shaped particles have a particle size of 50-100 mesh, and the shaped particles are then calcined at 400-700℃ for 1-5 hours to obtain calcined material;

[0025] Preferably, during the second acid impregnation, the weight ratio of the roasted material to the acid solution is 1:10-1:20. The acid used for the second impregnation includes at least one of hydrochloric acid, sulfuric acid, carborane acid, and trifluoromethanesulfonic acid. The concentration of the acid solution is 50-100%. The impregnation temperature is 25-35°C, and the time is 10-15 hours. The drying temperature is 60-140°C, and the time is 8-12 hours, to obtain a solid acid catalyst.

[0026] This invention provides a method for preparing a solid acid catalyst. The method includes: first impregnating mesoporous zirconium phosphate powder in an acidic solution, and drying it after impregnation to obtain acidified mesoporous zirconium phosphate powder; mixing the acidified mesoporous zirconium phosphate powder with starch, guar gum powder, glycerol, glass fiber and water evenly and then extruding it into granules; calcining the obtained granules to obtain calcined material; and second impregnating the calcined material in an acidic solution, and drying it after impregnation to obtain the solid acid catalyst. The above preparation method involves acid leaching of mesoporous zirconium phosphate powder, which allows it to adsorb and carry some acid. The powder is then mixed evenly with starch, guar gum powder, glycerol, glass fiber, and water before being extruded into granules. The aqueous solution of starch and guar gum powder has a certain viscosity, resulting in better molding after mixing with the acidified zirconium phosphate powder. It can also be used as a filler before catalyst calcination to expand the catalyst pores. Glycerol acts as a lubricant, and glass fiber enhances the mechanical strength of the granules. By mixing the above-mentioned additives with the acidified mesoporous zirconium phosphate powder, extruding it through a molding machine, and then calcining it, granules with good compressive strength and porous structure can be obtained. After acid leaching again, the granules can adsorb and carry a large amount of acidic substances within the porous structure, further enhancing the catalytic performance of the solid acid catalyst.

[0027] As can be seen, the present invention provides a method for preparing the above-mentioned solid acid catalyst. By using different zirconium and phosphorus sources to prepare zirconium phosphate solid powder, the obtained zirconium phosphate solid has a large specific surface area. After granulation treatment, a crude catalyst product is obtained. Subsequent calcination and impregnation can activate and modify the catalyst. Compared with conventional catalysts (such as sulfuric acid), this catalyst requires no complex post-processing and does not generate solid waste, making it environmentally friendly.

[0028] In some alternative embodiments, mesoporous zirconium phosphate powder is prepared using a hydrothermal method;

[0029] Preferably, the method includes the following steps: mixing an aqueous solution of phosphorus source and zirconium source with a structure directing agent, adjusting the pH of the mixed solution, placing it in a high-pressure sealed container for reaction, collecting the precipitate after the reaction is completed, washing, filtering and drying the precipitate, and then calcining and grinding it to obtain mesoporous zirconium phosphate solid powder.

[0030] Preferably, the phosphorus source includes at least one of phosphorous acid, hypophosphorous acid, and pyrophosphoric acid, and the zirconium source includes at least one of zirconium chloride, zirconium nitrate, zirconium sulfate, zirconium butoxide, zirconium dioxide, and zirconium oxychloride, and the P / Zr molar ratio of the phosphorus source to the zirconium source is 0.3-1.3;

[0031] Preferably, the structure-directing agent includes at least one of tetrapropylammonium hydroxide, ethylenediamine, n-butylamine, 1,8-octanediamine, F108, and P123, and the concentration of the structure-directing agent in the mixed solution is 30-300 g / L; the mass ratio of zirconium source to structure-directing agent is 0.1-1.

[0032] Preferably, ammonia is used to adjust the pH of the mixed solution to 6-8;

[0033] Preferably, the hydrothermal reaction temperature is 150-200℃, the reaction pressure is 0.1-0.3 MPa, and the reaction time is 2-8 hours.

[0034] Preferably, the water washing includes: washing the precipitate with deionized water 3-5 times, and the amount of water used for each wash is 10-20 times the amount of precipitate, and the washing temperature is 20-40℃;

[0035] Preferably, the drying temperature is 50-80℃; the drying time is 36-72h; the calcination temperature is 300-400℃; and the calcination time is 2-6h.

[0036] The addition of a structure-directing agent during the above preparation process can synthesize zirconium phosphate with a mesoporous structure, further increasing the specific surface area of ​​zirconium phosphate and giving the prepared mesoporous zirconium phosphate good adsorption properties. When acid-leached, it can fully adsorb acid, increase the acid loading, and thus improve the catalytic performance of the solid acid catalyst.

[0037] Secondly, this utility model provides an apparatus for preparing polysiloxane, which mainly includes: a raw material tank 1-1, a reaction tank 2-1 and a product tank 3-1. The raw material tank 1-1 is connected to the reaction tank 2-1, and the reaction tank 2-1 is connected to the product tank 3-1. A catalyst placement box 2-4 is provided in the reaction tank 2-1, and a solid acid catalyst prepared by the above preparation method is placed in the catalyst placement box 2-4.

[0038] In some alternative embodiments, a first valve 1-2 and a feed pump 1-7 are sequentially arranged between the outlet of the raw material tank 1-1 and the inlet of the reaction tank 2-1; a second valve 2-7 is arranged between the outlet of the reaction tank 2-1 and the inlet of the raw material tank 1-1; and a third valve 3-2 and a filter 3-3 are sequentially arranged between the outlet of the reaction tank 2-1 and the inlet of the product tank 3-1.

[0039] In some alternative embodiments, the reaction vessel 2-1 is provided with a number of alternating baffles 2-3, and the baffles 2-3 are provided with upper and lower support nets for fixing and supporting the catalyst placement box 2-4.

[0040] Preferably, a catalyst placement box 2-4 is detachably installed on the baffle 2-3 inside the reaction vessel 2-1;

[0041] Preferably, the catalyst placement box 2-4 is a rectangle with one side curved; the length of the catalyst placement box 2-4 is 1 / 2-2 / 3 of the diameter of the reaction vessel 2-1, the width is 1 / 4-1 / 3 of the diameter of the reaction vessel 2-1, and the height is 1 / 10-1 / 5 of the diameter of the reaction vessel 2-1;

[0042] Preferably, adjacent catalyst placement boxes 2-4 are placed in parallel opposite directions on each layer;

[0043] Preferably, the catalyst placement box 2-4 contains a catalyst and packing material A, wherein the particle size of packing material A is 50-100 mm;

[0044] Preferably, a filler B is placed between two adjacent catalyst placement boxes 2-4, and the particle size of the filler B is 5-30 mm.

[0045] Preferably, a filter screen 2-2 is provided at the bottom of the reaction vessel 2-1, a second heating layer 2-5 is provided on the outer wall, and a second temperature sensor 2-6 is provided inside the reaction vessel 2-1.

[0046] In some optional embodiments, the raw material tank 1-1 is provided with an electric stirring mechanism 1-6 and a first temperature sensor 1-3, and the outer wall is provided with a first heating layer 1-4.

[0047] This invention provides an apparatus for preparing polysiloxanes. Using the above apparatus to prepare polysiloxanes can more effectively improve the reaction efficiency, and the product can be separated into solid and liquid without further processing, achieving a green and environmentally friendly effect.

[0048] Thirdly, this utility model embodiment also provides a method for preparing polysiloxane using the above-mentioned apparatus, comprising the following steps: adding the reaction raw materials into the raw material tank 1-1, and loading the prepared solid acid catalyst into the catalyst placement box 2-4 and then filling it into the reaction tank 2-1, and introducing the reaction raw materials from the raw material tank 1-1 into the reaction tank 2-1 for reaction.

[0049] In some optional embodiments, the following steps are included: adding the reaction raw materials into the raw material tank 1-1, and loading the prepared solid acid catalyst into the catalyst placement box 2-4 and then into the reaction tank 2-1; turning on the stirring and heating in the raw material tank 1-1; mixing the reaction raw materials evenly and heating them to the preset temperature; opening the first valve 1-2 and starting the feed pump 1-7 so that the reaction raw materials are filtered through the filter screen 2-2 and enter the reaction tank 2-1 for reaction;

[0050] Preferably, the reaction raw materials in raw material tank 1-1 include: polydimethylcyclosiloxane and hexamethyldisiloxane end-capping agent, wherein the structure of polydimethylsiloxane is MD m M, m=5-10; M: -Si(CH3)3, D: -Si(CH3)2-O-;

[0051] Preferably, a solid acid catalyst and packing A are placed in the catalyst placement box 2-4 inside the reaction vessel 2-1, and packing B is placed between two adjacent catalyst placement boxes 2-4;

[0052] Preferably, the ratio of solid acid catalyst to filler A is 1:2 to 1:10;

[0053] Preferably, filler A includes one or more of molecular sieves, polymer microspheres, quartz sand, activated alumina spheres, and polytetrafluoroethylene microspheres;

[0054] Preferably, packing B includes zeolite, ceramic balls, stainless steel Raschig rings, stainless steel Pall rings, and stainless steel step rings;

[0055] Preferably, the stirring speed in the raw material tank 1-1 is 300-600 r / min;

[0056] Preferably, the feed flow rate of feed pumps 1-7 is 500-1500 mL / min;

[0057] Preferably, the reaction temperature inside reaction vessel 2-1 is 30-60℃;

[0058] Preferably, the process further includes: after the reaction raw materials in the reaction tank 2-1 have completed the reaction, the second valve 2-7 is opened to allow the reaction product to circulate back into the raw material tank 1-1. After each circulation, the gas phase data is sampled and tested to detect the content of the target component. When the content of the target component remains stable, the third valve 3-2 is opened, and after filtration by the filter 3-3, the product is discharged into the product tank 3-1.

[0059] Fourthly, this utility model embodiment also provides a method for preparing high-resilience polyurethane foam, which includes: preparing high-resilience polyurethane foam by compounding a surfactant with a polysiloxane prepared by the above preparation method and a polyether.

[0060] This invention provides a method for improving the preparation of target components in low molecular weight polysiloxanes. Using the solid acid catalyst and apparatus prepared herein, the content of the target components can be effectively increased, and the prepared low molecular weight polysiloxanes can effectively improve the open-cell ratio of high-resilience foams.

[0061] The present invention will be further described below with reference to the embodiments.

[0062] An apparatus for preparing polysiloxanes, see [link to apparatus]. Figure 1 It mainly includes: raw material tank 1-1, reaction tank 2-1 and product tank 3-1. Raw material tank 1-1 is connected to reaction tank 2-1, and reaction tank 2-1 is connected to product tank 3-1. A first valve 1-2 and a feed pump 1-7 are sequentially installed between the outlet of raw material tank 1-1 and the inlet of reaction tank 2-1. A second valve 2-7 is installed between the outlet of reaction tank 2-1 and the inlet of raw material tank 1-1. A third valve 3-2 and a filter 3-3 are sequentially installed between the outlet of reaction tank 2-1 and the inlet of product tank 3-1.

[0063] The raw material tank 1-1 is equipped with a first temperature sensor 1-3 and an electric stirring mechanism 1-6, a feeding port 1-5 is provided at the top, and a first heating layer 1-4 is provided on the outer wall.

[0064] See further Figure 2 and Figure 3 The bottom of the reaction vessel 2-1 is equipped with a filter screen 2-2, and the outer wall is equipped with a second heating layer 2-5. A second temperature sensor 2-6 is installed inside the reaction vessel 2-1. A catalyst placement box 2-4 is installed inside the reaction vessel 2-1, containing the solid acid catalyst prepared according to this invention. Several alternating baffles 2-3 are arranged inside the reaction vessel 2-1. Each baffle 2-3 has upper and lower support nets for fixing and supporting the catalyst placement box 2-4. The catalyst placement box 2-4 is detachably mounted on the baffles 2-3 inside the reaction vessel 2-1. The catalyst placement box 2-4 is rectangular with one side curved. The length of the catalyst placement box 2-4 is 1 / 2 to 2 / 3 of the diameter of the reaction vessel 2-1, the width is 1 / 4 to 1 / 3 of the diameter of the reaction vessel 2-1, and the height is equal to the diameter of the reaction vessel 2-1. 1 / 10-1 / 5 of the catalyst; adjacent catalyst placement boxes 2-4 are placed parallel to each other in each layer; catalyst placement box 2-4 contains catalyst and filler A, the particle size of filler A is 50-100; the ratio of solid acid catalyst to filler A is 1:2-1:10; filler A includes one or more of molecular sieve, polymer microspheres, quartz sand, activated alumina spheres, and polytetrafluoroethylene microspheres; filler B is placed between adjacent catalyst placement boxes 2-4, the particle size of filler B is 5-30mm.

[0065] The method for preparing polysiloxane using the above-described apparatus includes the following steps: Adding the reaction raw materials into the raw material tank 1-1 through the feed port 1-5; loading the prepared solid acid catalyst into the catalyst placement box 2-4 and then into the reaction tank 2-1; using the electric stirring mechanism 1-6 and the first heating layer 1-4 in the raw material tank 1-1 to stir and heat the reaction raw materials; monitoring the temperature of the reaction raw materials using the first temperature sensor 1-3 until the temperature reaches the preset temperature; opening the first valve 1-2 and starting the feed pump 1-7 to allow the reaction raw materials to pass through the filter screen 2-2 before entering the reaction tank. In reaction vessel 2-1, the reactants react under the heating of the second heating layer 2-5 and the catalysis of the solid acid catalyst in the catalyst placement box 2-3. During the reaction, the reaction temperature in reaction vessel 2-1 is monitored by the second temperature sensor 2-6. After one reaction cycle, the second valve 2-7 is opened to circulate the reaction product back into the raw material tank 1-1. After each cycle, gas phase data is sampled and tested to detect the content of the target component. Once the component content stabilizes, the third valve 3-2 is opened, and the product is filtered through filter 3-3 and discharged into product tank 3-1. Wherein:

[0066] The reaction materials in raw material tank 1-1 include: polydimethylcyclosiloxane and hexamethyldisiloxane end-capping agent. The structure of polydimethylsiloxane is MD. m M, m=5-10; M: -Si(CH3)3, D: -Si(CH3)2-O-; The stirring speed in raw material tank 1-1 is 300-600 r / min; The feed flow rate of feed pump 1-7 is 500-1500 mL / min; The reaction temperature in reaction tank 2-1 is 30-60℃.

[0067] Example 1

[0068] (1) Prepare 200g of aqueous solution by mixing 20g of phosphorous acid and 70g of zirconium chloride. Add 200mL of 100g / L ethylenediamine aqueous solution and stir until homogeneous. Adjust the pH of the solution to 6.0 by adding ammonia. Transfer the mixed solution to a high-pressure reactor and react at 180℃ and 0.1MPa for 5h. Filter and collect the solid precipitate to obtain 35g of solid precipitate. Wash the precipitate three times with deionized water at 30℃, using 400g of deionized water each time. Then dry it at 60℃ for 40h. After drying, calcine the dried material at 350℃ for 4h, and then grind it to obtain solid powder.

[0069] (2) The solid powder was immersed in 98% sulfuric acid at a solid-liquid weight ratio of 1:12 at 25℃ for 10 hours. After draining, it was dried at 150℃. The acidified solid powder was then mixed with starch, guar gum powder, glycerin, glass fiber, and water at a ratio of 100:5:10:10:10:30. After stirring at 50℃ for 30 minutes, the mixture was extruded into 50-mesh granules using a molding machine. The granules were then placed in an oven and calcined at 400℃ for 3 hours.

[0070] (3) Add the solid acid particles to 98% sulfuric acid at a solid-liquid weight ratio of 1:10 and soak them at 25°C for 8 hours. Then drain the liquid from the solid particles and place them in an oven to dry at 100°C for 5 hours. The resulting solid catalyst is A.

[0071] Example 2

[0072] (1) Prepare 200g of aqueous solution by mixing 8g of phosphorous acid, 7g of hypophosphorous acid, 18g of zirconium chloride, and 25g of zirconium oxychloride. Then add 280mL of P123 aqueous solution with a concentration of 150g / L and stir well. Add ammonia water to adjust the pH of the solution to 8.0. Then transfer the mixed solution to a high-pressure reactor and react for 6h at 200℃ and 0.2MPa. After that, filter and collect the solid precipitate to obtain 30g of solid precipitate. Wash the precipitate twice with deionized water at 30℃, using 550g of deionized water each time. Then dry it at 70℃ for 35h. After drying, calcine the dried material at 350℃ for 4h and then grind it to obtain solid powder.

[0073] (2) The solid powder was immersed in 100% trifluoromethanesulfonic acid at a solid-liquid weight ratio of 1:15 at 25°C for 9 hours. After draining, it was dried at 160°C. The acidified solid powder was then mixed with starch, guar gum powder, glycerin, glass fiber, and water at a ratio of 100:6:10:12:10:35. After stirring at 60°C for 35 minutes, the mixture was extruded into 80-mesh granules using a molding machine. The granules were then placed in an oven and calcined at 400°C for 3 hours.

[0074] (3) Place it in 98% trifluoromethanesulfonic acid at a solid-liquid weight ratio of 1:15 and soak it at 25°C for 6 hours; then drain the liquid from the solid particles and place them in an oven to dry at 100°C for 4 hours. The solid catalyst B is then taken out.

[0075] Example 3

[0076] Polysiloxanes were synthesized according to the MD6M structure. 36.63 kg of octamethylcyclotetrasiloxane and 13.37 kg of hexamethyldisiloxane were added to raw material tank 1-1 and stirred. Then, 1.00 kg of solid acid catalyst A prepared in Example 1 was mixed evenly with 8.00 kg of 4A molecular sieve. The mixture was added to an assemblable catalyst box, which was then placed in reaction tank 2-1. Additionally, 10 mm diameter stainless steel Raschig rings were filled into reaction tank 2-1. Stirring and heating were started in raw material tank 1-1. When the material temperature reached 50°C, feed pump 1-7 was turned on, and the feed flow rate was controlled at 1000 mL / min. The mixture was passed through reaction tank 2-1 at 50°C and returned to raw material tank 1-1 for recirculation. After each cycle, a gas phase sample was taken for testing to determine the target component content. After 6 cycles, the target component content remained stable, and the material was discharged.

[0077] Example 4

[0078] Polysiloxanes were synthesized according to the MD6M structure. 36.63 kg of octamethylcyclotetrasiloxane and 13.37 kg of hexamethyldisiloxane were added to raw material tank 1-1 and stirred. Then, 1.00 kg of solid acid catalyst A prepared in Example 2 was mixed evenly with 8.00 kg of 4A molecular sieve. The mixture was added to an assemblable catalyst box, which was then placed in reaction tank 2-1. Additionally, 10 mm diameter stainless steel Raschig rings were filled into reaction tank 2-1. Stirring and heating were started in raw material tank 1-1. When the material temperature reached 50°C, feed pump 1-7 was turned on, and the feed flow rate was controlled at 1000 mL / min. The mixture was passed through reaction tank 2-1 at 40°C and returned to raw material tank 1-1 for recirculation. After each cycle, a gas phase sample was taken for testing to determine the target component content. After 5 cycles, the target component content remained stable, and the product was collected into product tank 3-1-1.

[0079] Example 5

[0080] Polysiloxanes were synthesized according to the MD6M structure. 36.63 kg of octamethylcyclotetrasiloxane and 13.37 kg of hexamethyldisiloxane were added to raw material tank 1-1 and stirred. Then, 2.00 kg of solid acid catalyst B prepared in Example 2 was mixed evenly with 5.00 kg of 4A molecular sieve. The mixture was added to an assemblable catalyst box, which was then placed in reaction tank 2-1. Additionally, 15 mm diameter stainless steel Raschig rings were filled to fill the entire reaction tank 2-1. Stirring and heating were started in raw material tank 1-1. When the material temperature reached 40°C, feed pump 1-7 was turned on, and the feed flow rate was controlled at 1200 mL / min. The mixture was passed through the 60°C reaction tank 2-1 and returned to raw material tank 1-1 for recirculation. After each circulation, a gas phase sample was taken for testing to determine the target component content. After two circulations, the target component content remained stable, and the material was discharged.

[0081] Example 6

[0082] Polysiloxanes were synthesized according to the MD8M structure. 39.26 kg of octamethylcyclotetrasiloxane and 10.74 kg of hexamethyldisiloxane were added to raw material tank 1-1 and stirred. Then, 1.50 kg of solid acid catalyst B prepared in Example 2 was mixed evenly with 5.00 kg of 4A molecular sieve. The mixture was added to an assemblable catalyst box, which was then placed in reaction tank 2-1. Additionally, 25 mm diameter stainless steel Pall rings were filled into reaction tank 2-1. Stirring and heating were started in raw material tank 1-1. When the material temperature reached 45°C, feed pump 1-7 was turned on, and the feed flow rate was controlled at 1000 mL / min. The mixture passed through reaction tank 2-1 at 45°C and returned to raw material tank 1-1 for recirculation. After each cycle, a gas phase sample was taken for testing to determine the target component content. After three cycles, the target component content remained stable, and the material was discharged.

[0083] Example 7

[0084] Polysiloxanes were synthesized according to the MD9M structure. 40.22 kg of octamethylcyclotetrasiloxane and 9.78 kg of hexamethyldisiloxane were added to raw material tank 1-1 and stirred. Then, 1.20 kg of solid acid catalyst B prepared in Example 1 was mixed evenly with 5.00 kg of 4A molecular sieve. The mixture was added to an assemblable catalyst box, which was then placed in reaction tank 2-1. Additionally, 20 mm diameter stainless steel Pall rings were filled into reaction tank 2-1. Stirring and heating were started in raw material tank 1-1. When the material temperature reached 45°C, feed pump 1-7 was turned on, and the feed flow rate was controlled at 1000 mL / min. The mixture was passed through reaction tank 2-1 at 45°C and returned to raw material tank 1-1 for recirculation. After each cycle, a gas phase sample was taken for testing to determine the target component content. After four cycles, the target component content remained stable, and the material was discharged.

[0085] Example 8

[0086] Press MD 10 For the synthesis of polysiloxanes using the M structure, 41.02 kg of octamethylcyclotetrasiloxane and 8.98 kg of hexamethyldisiloxane were added to raw material tank 1-1 and stirred. Then, 2.00 kg of solid acid catalyst B prepared in Example 2 was mixed evenly with 5.00 kg of 4A molecular sieve. The mixture was added to an assemblable catalyst box, which was then placed in reaction tank 2-1. Additionally, 20 mm diameter ceramic balls were filled into reaction tank 2-1. Stirring and heating were started in raw material tank 1-1. When the material temperature reached 40°C, feed pump 1-7 was turned on, and the feed flow rate was controlled at 1200 mL / min. The mixture was passed through reaction tank 2-1 at 60°C and returned to raw material tank 1-1 for recirculation. After each cycle, a gas phase sample was taken for testing to determine the target component content. After three cycles, the target component content remained stable, and the material was discharged.

[0087] Comparative Example 1

[0088] Polysiloxanes were synthesized according to the MD6M structure. 36.63 kg of octamethylcyclotetrasiloxane and 13.37 kg of hexamethyldisiloxane were added to a reactor, followed by 6.00 kg of bleaching clay. The stirring and heating in raw material tank 1-1 were started. When the material temperature reached 80℃, the temperature was maintained, and gas phase samples were taken hourly to test the content of the target component. When the holding time reached 4 hours and the content of the target component remained stable, the material was discharged.

[0089] Comparative Example 2

[0090] Polysiloxanes were synthesized according to the MD6M structure. 36.63 kg of octamethylcyclotetrasiloxane and 13.37 kg of hexamethyldisiloxane were added to a reactor, followed by 4.00 kg of sulfuric acid. The raw material tank 1-1 was stirred and heated. When the material temperature reached 60℃, it was held at this temperature for a period of time, with hourly gas phase samples taken to test the content of the target component. After 6 hours of holding, the content of the target component remained stable. 24.00 kg of sodium bicarbonate was then added for neutralization for 4 hours, followed by filtration and discharge.

[0091] Comparative Example 3

[0092] Polysiloxanes were synthesized according to the MD6M structure. 36.63 kg of octamethylcyclotetrasiloxane and 13.37 kg of hexamethyldisiloxane were added to a reactor, followed by 8.00 kg of cation exchange resin. The stirring and heating in raw material tank 1-1 were started. When the material temperature reached 60℃, the temperature was maintained, and gas phase samples were taken hourly to test the content of the target component. When the content of the target component remained stable after 4 hours of holding, the material was discharged.

[0093] Comparative Example 4

[0094] Polysiloxanes were synthesized according to the MD8M structure. 39.26 kg of octamethylcyclotetrasiloxane and 10.74 kg of hexamethyldisiloxane were added to a reactor, followed by 6.00 kg of kaolin. The stirring and heating in raw material tank 1-1 were started. When the material temperature reached 80℃, the temperature was maintained, and gas phase samples were taken hourly to test the content of the target component. When the holding time reached 4 hours and the content of the target component remained stable, the material was discharged.

[0095] Comparative Example 5

[0096] Polysiloxanes were synthesized according to the MD9M structure. 40.22 kg of octamethylcyclotetrasiloxane and 9.78 kg of hexamethyldisiloxane were added to a reactor, followed by 4.00 kg of sulfuric acid. The raw material tank 1-1 was stirred and heated. When the material temperature reached 60°C, it was held at this temperature for a period of time, with hourly gas phase samples taken to test the content of the target component. When the holding time reached 6 hours and the content of the target component remained stable, 24.00 kg of sodium bicarbonate was added for neutralization for 4 hours, and then the mixture was filtered and discharged.

[0097] Comparative Example 6

[0098] Press MD 10 Polysiloxane synthesis was performed using the M-structure. 41.02 kg of octamethylcyclotetrasiloxane and 8.98 kg of hexamethyldisiloxane were added to a reactor, followed by 8.00 kg of cation exchange resin. The raw material tank 1-1 was stirred and heated. When the material temperature reached 60°C, it was held at this temperature for a period of time. Gas phase samples were taken hourly to test the content of the target component. When the holding time reached 6 hours and the content of the target component remained stable, the material was discharged.

[0099] Comparative Example 7

[0100] Polysiloxanes were synthesized according to the MD6M structure. 36.63 kg of octamethylcyclotetrasiloxane and 13.37 kg of hexamethyldisiloxane were added to raw material tank 1-1 and stirred. Then, 1.00 kg of solid acid catalyst C (similar to the steps in Example 1, except that the structure-directing agent ethylenediamine was not added during the preparation of zirconium phosphate, while the other steps remained unchanged) was mixed evenly with 8.00 kg of 4A molecular sieve. The mixture was added to an assemblable catalyst box, which was then placed in reaction tank 2-1. Additionally, 10 mm diameter stainless steel Raschig rings were filled to fill the entire reaction tank 2-1. Stirring and heating were started in raw material tank 1-1. When the material temperature reached 50°C, feed pump 1-7 was turned on, and the feed flow rate was controlled at 1000 mL / min. The mixture was passed through the 50°C reaction tank 2-1 and returned to raw material tank 1-1 for recirculation. After each cycle, a gas phase sample was taken for testing to determine the target component content. After 10 cycles, the target component content remained stable, and the material was discharged.

[0101] Comparative Example 8

[0102] Similar to the steps in Example 3, except that packing material A is not added to the catalyst box and packing material B is not added to the reaction vessel, while the other conditions remain unchanged.

[0103] Table 1 below shows the component content of Examples 3-8 and Comparative Examples 1-8.

[0104] Table 1

[0105]

[0106] Based on the component analysis results of the MD6M polydimethylsiloxane prepared in Examples 3-5 and Comparative Examples 1-3, compared with catalysts such as clay, sulfuric acid, and cation exchange resin, the solid catalyst, apparatus, and process prepared by this invention can effectively increase the content of the target component.

[0107] Based on the component analysis results of polydimethylsiloxanes with different structures prepared in Examples 6-8 and Comparative Examples 4-6, compared with clay, sulfuric acid, and cation exchange resin catalysts (manufacturer: Jiangyin Nanda Synthetic Chemical Co., Ltd., resin model: amberlyst15), the solid catalyst, apparatus and process prepared by this invention can effectively increase the content of the target component.

[0108] In summary, the low molecular weight polydimethylsiloxane prepared using the catalyst and apparatus provided in this paper can effectively improve MD. m The content of M and m = 5-10 components can be reduced, and the content of cyclic compounds can be decreased.

[0109] The polysiloxanes and polyethers obtained in Examples 3-5 and Comparative Examples 1-3 were compounded and used as surfactants to prepare high-resilience polyurethane foam. Specifically, the high-resilience polyurethane foam was prepared by reacting component X and component Y, and the preparation method is as follows:

[0110] Preparation of component X: Based on the mass fractions, the weighed polyol, catalyst, foaming agent and surfactant are mixed and stirred at room temperature for 20 seconds according to the formula in Table 2.

[0111] Table 3 below is an evaluation of the formulations in Table 2.

[0112] Table 2

[0113]

[0114] Component Y, TM20, refers to a mixture of TDI (toluene diisocyanate) and MDI (diphenylmethane diisocyanate), with TDI accounting for 80% and MDI accounting for 20%.

[0115] In use, mix components X and Y at a weight ratio of X:Y = 100:35, stir for 5 seconds at 2000 r / min, and pour into a standard mold (mold temperature 25℃) before the foam has freely expanded. The foam undergoes expansion, growth, and curing to produce high-resilience polyurethane foam. Data is then tested using a FOAMAT285 instrument. The standard square mold venting force test method is referenced in GB / T10807-2006 "Determination of Hardness of Flexible Foam Polymer Materials (Indentation Method)"; other test methods are referenced in QBT2080-2010 "High-Resilience Flexible Polyurethane Foam Plastics".

[0116] Table 3 below shows the test results of the venting force of the standard foam mold corresponding to the examples and comparative examples.

[0117] Table 3

[0118]

[0119] Based on the foam test results, compared with polydimethylsiloxane prepared by processes using kaolin, sulfuric acid, and cation exchange resin, the polydimethylsiloxane prepared by this invention, when applied to the preparation of high-resilience polyurethane foam, exhibits a significant decrease in foam stress, a substantial increase in resilience and air permeability, and a significant improvement in the foam's open-cell performance.

[0120] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An apparatus for preparing polysiloxanes, characterized in that, Mainly includes: raw material tanks (1-1), reaction vessel (2-1) and product vessel (3-1), wherein the raw material vessel (1-1) is connected to the reaction vessel (2-1), the reaction vessel (2-1) is connected to the product vessel (3-1), and a catalyst placement box (2-4) is provided inside the reaction vessel (2-1), wherein a solid acid catalyst is placed inside the catalyst placement box (2-4); A first valve (1-2) and a feed pump (1-7) are sequentially arranged between the outlet of the raw material tank (1-1) and the inlet of the reaction tank (2-1); a second valve (2-7) is arranged between the outlet of the reaction tank (2-1) and the inlet of the raw material tank (1-1); and a third valve (3-2) and a filter (3-3) are sequentially arranged between the outlet of the reaction tank (2-1) and the inlet of the product tank (3-1).

2. The apparatus according to claim 1, characterized in that, The reaction vessel (2-1) is provided with several alternating baffles (2-3), and the baffles (2-3) are provided with upper and lower support nets for fixing and supporting the catalyst placement box (2-4).

3. The apparatus according to claim 2, characterized in that, A catalyst placement box (2-4) is detachably installed on the baffle (2-3) inside the reaction vessel (2-1).

4. The apparatus according to claim 1, characterized in that, The catalyst placement box (2-4) is a rectangle with one side curved.

5. The apparatus according to claim 1, characterized in that, The length of the catalyst placement box (2-4) is 1 / 2 to 2 / 3 of the diameter of the reaction vessel (2-1), the width is 1 / 4 to 1 / 3 of the diameter of the reaction vessel (2-1), and the height is 1 / 10 to 1 / 5 of the diameter of the reaction vessel (2-1).

6. The apparatus according to claim 1, characterized in that, Adjacent catalyst placement boxes (2-4) are placed parallel to each other in each layer.

7. The apparatus according to claim 1, characterized in that, The catalyst placement box (2-4) contains a catalyst and filler A. The particle size of filler A is 50-100 mm. Filler B is placed between two adjacent catalyst placement boxes (2-4). The particle size of filler B is 5-30 mm.

8. The apparatus according to claim 1, characterized in that, The bottom of the reaction vessel (2-1) is provided with a filter screen (2-2), the outer wall is provided with a second heating layer (2-5), and the interior of the reaction vessel (2-1) is provided with a second temperature sensor (2-6).

9. The apparatus according to claim 1, characterized in that, The raw material tank (1-1) is equipped with a first temperature sensor (1-3) and an electric stirring mechanism (1-6), a feeding port (1-5) is provided at the top, and a first heating layer (1-4) is provided on the outer wall.

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