Special sealant for shaping imitation cake and preparation method thereof
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANDONG JINGMAO NEW MATERIAL CO LTD
- Filing Date
- 2026-04-30
- Publication Date
- 2026-05-29
Smart Images
Figure SMS_1
Abstract
Description
Technical Field
[0001] This invention relates to the field of adhesive technology, specifically to a special sealant for shaping simulated cakes and its preparation method. Background Technology
[0002] As a core application product in fields such as commercial display, teaching and training, wedding decoration, and arts and crafts, the surface sealing treatment of simulated cakes is a key process to achieve shape fixation, substrate protection and simulated texture presentation. The performance of the sealant directly determines the production efficiency, finished product stability and long-term display effect of simulated cakes.
[0003] With the increasing scale and sophistication of the simulated cake industry, the market has placed increasingly stringent demands on product delivery cycles, design complexity, long-term weather resistance, and environmental safety. Traditional sealants used for shaping simulated cakes generally suffer from a core flaw: long curing and setting cycles. Conventional shaping and bonding curing can take tens of hours, significantly reducing production efficiency, increasing time and labor costs for large-scale production, and directly extending product delivery cycles, making it difficult to meet the industry's fast-paced production needs. Furthermore, existing sealants also suffer from problems such as easy deformation after setting, yellowing and aging under long-term UV exposure, and excessive migration of harmful substances, failing to simultaneously meet the multiple requirements of rapid and precise shaping, long-term stable display, and food-grade environmental safety for simulated cakes.
[0004] In summary, existing sealant products for simulating cake shaping still have the following technical problems: long setting time, easy deformation, poor aging resistance and environmental friendliness. Summary of the Invention
[0005] In order to solve the above-mentioned problems in the prior art, the present invention provides a special sealant for shaping simulated cakes and its preparation method, and achieves the following objectives: to prepare a finished sealant with short setting time, excellent aging resistance and environmental friendliness.
[0006] To achieve the above objectives, the following technical solution is adopted: A special sealant for shaping simulated cakes, used for shaping simulated cakes made of polystyrene foam.
[0007] A special sealant for shaping simulated cakes, the raw materials of which include: 60-75 parts of α,ω-dihydroxypolydimethylsiloxane, 5-10 parts of methyltributanone oxime silane, 0.1-0.5 parts of catalyst, 3-8 parts of composite regulator, 5-15 parts of food-grade white oil, 1-3 parts of γ-aminopropyltriethoxysilane, 4-8 parts of nano-calcium carbonate-supported end-capped isocyanate, and 0.5-2 parts of deionized water. All the above parts are by weight.
[0008] The viscosity of the α,ω-dihydroxypolydimethylsiloxane is 5000-15000 mPa·s.
[0009] The catalyst is dibutyltin dilaurate.
[0010] The composite regulator is a mixture of modified nano-silica and antioxidant, with a mass ratio of (2-5):(1-3) for the modified nano-silica and antioxidant, and the antioxidant is antioxidant 1010.
[0011] The modified nano-silica: the modifier used is silane coupling agent KH-550, and the mass ratio of silane coupling agent KH-550 to silica is (1-3):20.
[0012] The nano-calcium carbonate-supported end-capped isocyanate: the raw materials include nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate, with a mass ratio of 1:(15-25):(1.5-3):(0.9-1.1).
[0013] A method for preparing a sealant specifically for shaping simulated cakes includes the following steps: Step 1: Preparation of the composite regulator Modified nano-silica was mixed evenly with antioxidant 1010 to obtain a composite regulator.
[0014] The mass ratio of the modified nano-silica to antioxidant 1010 is (2-5):(1-3).
[0015] The modified nano silica: The modifier used is silane coupling agent KH-550, and the mass ratio of silane coupling agent KH-550 to silica is (1-3):20. The preparation method is as follows: (1) Disperse nano silica in anhydrous ethanol; (2) Add silane coupling agent KH-550 and stir for 2-4 hours at a temperature of 60-80℃; (3) After drying, the modified nano silica is obtained; The particle size of the nano silica is 10-50nm.
[0016] Step 2: Preparation of end-capped isocyanate supported on nano-calcium carbonate Nano-calcium carbonate was ultrasonically cleaned with dilute hydrochloric acid solution for 5-10 minutes, then washed with deionized water until neutral, and dried to obtain pretreated nano-calcium carbonate. Toluene and pretreated nano-calcium carbonate were mixed and ultrasonically dispersed for 20-40 minutes. End-capped isocyanate was added to the mixture, the temperature was raised to 40-60℃, nitrogen gas was purged, and the mixture was stirred at a rate of 300-500 rpm for 1-3 hours. The product was then vacuum dried to obtain end-capped isocyanate supported on nano-calcium carbonate.
[0017] The nano-calcium carbonate particles have a diameter of 20-50 nm; the concentration of the dilute hydrochloric acid solution is 0.4-0.6 wt%.
[0018] The mass ratio of the nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and capped isocyanate is 1:(15-25):(1.5-3):(0.9-1.1).
[0019] The ultrasonic dispersion frequency is 30-50kHz.
[0020] Step 3: Preparation of prepolymer Add α,ω-dihydroxypolydimethylsiloxane and food-grade white oil to the reactor, set the temperature inside the reactor to 25-30℃, the stirring speed to 300-500 rpm, and stir for 10-15 minutes.
[0021] Add the catalyst and methyl tributanone oxime silane to the reactor, heat to 40-50℃, and stir for 20-30 minutes to form a prepolymer. The catalyst is dibutyltin dilaurate.
[0022] Step 4: Add additives Add the composite regulator and γ-aminopropyltriethoxysilane to the reactor containing the prepolymer, increase the stirring speed of the reactor to 800-1000 rpm, adjust the vacuum degree to -0.08 to -0.09 MPa, and stir for 30-40 minutes to ensure that the additives are evenly dispersed.
[0023] Step 5: Obtain the finished product After adding the additives, add nano-calcium carbonate-supported end-capped isocyanate and deionized water to the reactor. Control the temperature inside the reactor at 40-50℃ and stir for 10-15 minutes at a stirring speed of 800-1000 rpm. Then raise the temperature inside the reactor to 130-150℃ and maintain this temperature while stirring for 20-25 minutes. Finally, cool to room temperature and vacuum stir for 10-15 minutes to obtain the finished product.
[0024] The beneficial effects of this invention are as follows: 1. The sealant of this invention is used for simulating cake shaping. The nano-calcium carbonate-loaded end-capped isocyanate in the sealant acts as a latent crosslinking agent. The released isocyanate groups can react rapidly with hydroxyl and amino groups in the sealant, greatly improving the shaping efficiency. The setting time of the sealant for simulating cake shaping is 4-5 minutes, and the deformation rate after 30 days is 1.2-1.8%.
[0025] 2. This invention significantly improves the aging performance of the sealant through a specific composite modifier. Testing showed that the yellowing index ΔE of the sealant after 1000 hours of UV aging was 1.3-1.4.
[0026] 3. According to the test, the migration amount of harmful substances in the sealant prepared by the present invention is 0.006-0.009 mg / kg. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.
[0028] Example 1: A special sealant for shaping simulated cakes A special sealant for shaping simulated cakes, used for shaping simulated cakes made of polystyrene foam.
[0029] A special sealant for shaping simulated cakes, the raw materials of which include: 68 parts of α,ω-dihydroxypolydimethylsiloxane, 7 parts of methyltributanone oxime silane, 0.3 parts of catalyst, 5 parts of composite regulator, 10 parts of food-grade white oil, 2 parts of γ-aminopropyltriethoxysilane, 6 parts of nano-calcium carbonate-supported end-capped isocyanate, and 1 part of deionized water; all the above parts are by weight.
[0030] The viscosity of the α,ω-dihydroxypolydimethylsiloxane is 5000-15000 mPa·s.
[0031] The catalyst is dibutyltin dilaurate.
[0032] The composite regulator is a mixture of modified nano-silica and antioxidant, with a mass ratio of modified nano-silica to antioxidant of 4:2, and the antioxidant is antioxidant 1010.
[0033] The modified nano-silica uses silane coupling agent KH-550 as the modifier, and the mass ratio of silane coupling agent KH-550 to silica is 2:20.
[0034] The nano-calcium carbonate-supported end-capped isocyanate consists of nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate in a mass ratio of 1:20:2:1.
[0035] A method for preparing a sealant specifically for shaping simulated cakes includes the following steps: Step 1: Preparation of the composite regulator Modified nano-silica and antioxidant 1010 were mixed evenly at a mass ratio of 4:2 to obtain a composite regulator. The modified nano-silica used was silane coupling agent KH-550, and the mass ratio of silane coupling agent KH-550 to silica was 2:20. The preparation method was as follows: (1) Disperse nano-silica in anhydrous ethanol; (2) Add silane coupling agent KH-550 and stir for 3 hours at a temperature of 70°C; (3) After drying, modified nano-silica was obtained; the particle size of the nano-silica was 10-50 nm.
[0036] Step 2: Preparation of end-capped isocyanate supported on nano-calcium carbonate The raw materials used include: nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate, with a mass ratio of 1:20:2:1. The preparation method is as follows: (1) Sonically clean the nano-calcium carbonate with dilute hydrochloric acid solution for 7 minutes, then wash it with deionized water until neutral, and dry it for later use; the nano-calcium carbonate has a particle size of 20-50 nm; the concentration of the dilute hydrochloric acid solution is 0.5 wt%. (2) Mix toluene and dried nano-calcium carbonate, and ultrasonically disperse for 30 minutes. Add end-capped isocyanate to the mixture, and stir at a rate of 400 rpm for 2 hours under nitrogen protection at a temperature of 50℃. The product obtained is vacuum dried to obtain end-capped isocyanate loaded with nano-calcium carbonate. The ultrasonic dispersion frequency is 40 kHz.
[0037] The terminated isocyanate used is Covestro BL3175SN.
[0038] Step 3: Preparation of prepolymer Add α,ω-dihydroxypolydimethylsiloxane and food-grade white oil to the reactor, set the reactor temperature to 27°C, and the stirring speed to 400 rpm for 13 minutes.
[0039] The catalyst and methyl tributanone oxime silane were added to the reactor, the temperature was raised to 45°C, and the mixture was stirred at this temperature for 25 minutes to form a prepolymer. The catalyst was dibutyltin dilaurate.
[0040] Step 4: Add additives The composite regulator and γ-aminopropyltriethoxysilane were added to the reactor containing the prepolymer. The stirring speed of the reactor was increased to 900 rpm, the vacuum degree was adjusted to -0.09 MPa, and the mixture was stirred for 35 minutes to ensure that the additives were evenly dispersed.
[0041] Step 5: Obtain the finished product After adding the additives, nano-calcium carbonate-supported end-capped isocyanate and deionized water are added to the reactor. The temperature inside the reactor is controlled at 45°C, and the mixture is stirred for 13 minutes at a stirring speed of 900 rpm. Then, the temperature inside the reactor is raised to 140°C and maintained at this temperature while stirring for 22 minutes. Finally, the temperature is lowered to room temperature, and the mixture is stirred under vacuum for 13 minutes to obtain the final product.
[0042] Example 2: A sealant specifically for shaping simulated cakes A special sealant for shaping simulated cakes, used for shaping simulated cakes made of polystyrene foam.
[0043] A special sealant for shaping simulated cakes, the raw materials of which include: 60 parts of α,ω-dihydroxypolydimethylsiloxane, 5 parts of methyltributanone oxime silane, 0.1 parts of catalyst, 3 parts of composite regulator, 5 parts of food-grade white oil, 1 part of γ-aminopropyltriethoxysilane, 4 parts of nano-calcium carbonate-supported end-capped isocyanate, and 0.5 parts of deionized water; all the above parts are by weight.
[0044] The viscosity of the α,ω-dihydroxypolydimethylsiloxane is 5000-15000 mPa·s.
[0045] The catalyst is dibutyltin dilaurate.
[0046] The composite regulator is a mixture of modified nano-silica and antioxidant, with a mass ratio of modified nano-silica to antioxidant of 2:1, and the antioxidant is antioxidant 1010.
[0047] The modified nano-silica uses silane coupling agent KH-550 as the modifier, and the mass ratio of silane coupling agent KH-550 to silica is 1:20.
[0048] The nano-calcium carbonate-supported end-capped isocyanate consists of nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate in a mass ratio of 1:15:1.5:0.9.
[0049] A method for preparing a sealant specifically for shaping simulated cakes includes the following steps: Step 1: Preparation of the composite regulator Modified nano-silica and antioxidant 1010 were mixed evenly at a mass ratio of 2:1 to obtain a composite regulator. The modified nano-silica used was silane coupling agent KH-550, and the mass ratio of silane coupling agent KH-550 to silica was 1:20. The preparation method was as follows: (1) Disperse nano-silica in anhydrous ethanol; (2) Add silane coupling agent KH-550 and stir for 4 hours at a temperature of 60℃; (3) After drying, modified nano-silica was obtained; the particle size of the nano-silica was 10-50 nm.
[0050] Step 2: Preparation of end-capped isocyanate supported on nano-calcium carbonate The raw materials used include: nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate, with a mass ratio of 1:15:1.5:0.9. The preparation method is as follows: (1) Sonically clean the nano-calcium carbonate with dilute hydrochloric acid solution for 5 minutes, then wash it with deionized water until neutral, and dry it for later use; the nano-calcium carbonate has a particle size of 20-50 nm; the concentration of the dilute hydrochloric acid solution is 0.4 wt%. (2) Mix toluene and dried nano-calcium carbonate, and ultrasonically disperse for 20 minutes. Add end-capped isocyanate to the mixture, and stir at a rate of 300 rpm for 3 hours under nitrogen protection at a temperature of 40℃. The product obtained is vacuum dried to obtain end-capped isocyanate loaded with nano-calcium carbonate. The ultrasonic dispersion frequency is 50 kHz.
[0051] The terminated isocyanate used is Covestro BL3175SN.
[0052] Step 3: Preparation of prepolymer Add α,ω-dihydroxypolydimethylsiloxane and food-grade white oil to the reactor, set the reactor temperature to 25℃, the stirring speed to 500 rpm, and stir for 15 minutes.
[0053] The catalyst and methyl tributanone oxime silane were added to the reactor, the temperature was raised to 40°C, and the mixture was stirred at this temperature for 30 minutes to form a prepolymer. The catalyst was dibutyltin dilaurate.
[0054] Step 4: Add additives The composite regulator and γ-aminopropyltriethoxysilane were added to the reactor containing the prepolymer. The stirring speed of the reactor was increased to 800 rpm, the vacuum degree was adjusted to -0.08 MPa, and the mixture was stirred for 40 minutes to ensure that the additives were evenly dispersed.
[0055] Step 5: Obtain the finished product After adding the additives, nano-calcium carbonate-supported end-capped isocyanate and deionized water are added to the reactor. The temperature inside the reactor is controlled at 40°C, and the mixture is stirred for 15 minutes at a stirring speed of 800 rpm. Then, the temperature inside the reactor is raised to 130°C and maintained at this temperature while stirring for 25 minutes. Finally, the temperature is lowered to room temperature, and the mixture is stirred under vacuum for 10 minutes to obtain the final product.
[0056] Example 3: A special sealant for shaping simulated cakes A special sealant for shaping simulated cakes, used for shaping simulated cakes made of polystyrene foam.
[0057] A special sealant for shaping simulated cakes, the raw materials of which include: 75 parts of α,ω-dihydroxypolydimethylsiloxane, 10 parts of methyltributanone oxime silane, 0.5 parts of catalyst, 8 parts of composite regulator, 15 parts of food-grade white oil, 3 parts of γ-aminopropyltriethoxysilane, 8 parts of nano-calcium carbonate-supported end-capped isocyanate, and 2 parts of deionized water; all the above parts are by weight.
[0058] The viscosity of the α,ω-dihydroxypolydimethylsiloxane is 5000-15000 mPa·s.
[0059] The catalyst is dibutyltin dilaurate.
[0060] The composite regulator is a mixture of modified nano-silica and antioxidant, with a mass ratio of modified nano-silica to antioxidant of 5:3, and the antioxidant is antioxidant 1010.
[0061] The modified nano-silica uses silane coupling agent KH-550 as the modifier, and the mass ratio of silane coupling agent KH-550 to silica is 3:20.
[0062] The nano-calcium carbonate-supported end-capped isocyanate: the raw materials include nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate, with a mass ratio of 1:25:3:1.1.
[0063] A method for preparing a sealant specifically for shaping simulated cakes includes the following steps: Step 1: Preparation of the composite regulator Modified nano-silica and antioxidant 1010 were mixed evenly at a mass ratio of 5:3 to obtain a composite regulator. The modified nano-silica used was silane coupling agent KH-550, and the mass ratio of silane coupling agent KH-550 to silica was 3:20. The preparation method was as follows: (1) Disperse nano-silica in anhydrous ethanol; (2) Add silane coupling agent KH-550 and stir for 2 hours at a temperature of 80℃; (3) Dry to obtain modified nano-silica; The particle size of the nano-silica was 10-50nm.
[0064] Step 2: Preparation of end-capped isocyanate supported on nano-calcium carbonate The raw materials used include: nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate, with a mass ratio of 1:25:3:1.1. The preparation method is as follows: (1) Sonically clean the nano-calcium carbonate with dilute hydrochloric acid solution for 10 minutes, then wash it with deionized water until neutral, and dry it for later use; the nano-calcium carbonate has a particle size of 20-50 nm; the concentration of the dilute hydrochloric acid solution is 0.6 wt%. (2) Mix toluene and dried nano-calcium carbonate, and ultrasonically disperse for 40 minutes. Add end-capped isocyanate to the mixture, and stir at a rate of 500 rpm for 1 hour under nitrogen protection at a temperature of 60℃. The product obtained is vacuum dried to obtain end-capped isocyanate loaded with nano-calcium carbonate. The ultrasonic dispersion frequency is 30 kHz.
[0065] The terminated isocyanate used is Covestro BL3175SN.
[0066] Step 3: Preparation of prepolymer Add α,ω-dihydroxypolydimethylsiloxane and food-grade white oil to the reactor, set the reactor temperature to 30℃, the stirring speed to 300 rpm, and stir for 10 minutes.
[0067] The catalyst and methyl tributanone oxime silane were added to the reactor, the temperature was raised to 50°C, and the mixture was stirred at this temperature for 20 minutes to form a prepolymer. The catalyst was dibutyltin dilaurate.
[0068] Step 4: Add additives The composite regulator and γ-aminopropyltriethoxysilane were added to the reactor containing the prepolymer. The stirring speed of the reactor was increased to 1000 rpm, the vacuum degree was adjusted to -0.09 MPa, and the mixture was stirred for 30 minutes to ensure that the additives were evenly dispersed.
[0069] Step 5: Obtain the finished product After adding the additives, nano-calcium carbonate-supported end-capped isocyanate and deionized water are added to the reactor. The reactor temperature is controlled at 50°C, and the mixture is stirred for 10 minutes at a stirring speed of 1000 rpm. Then, the reactor temperature is raised to 150°C and maintained at this temperature while stirring for 20 minutes. Finally, the mixture is cooled to room temperature and stirred under vacuum for 15 minutes to obtain the final product.
[0070] Comparative Example 1 Based on Example 1, the nano-calcium carbonate-supported end-capped isocyanate in the raw material is replaced with an equal amount of end-capped isocyanate, step 2 is omitted, and other operations are the same as in Example 1. The specific operations are as follows: Step 1: Preparation of the composite regulator The steps are the same as those in "Preparation of Composite Regulator" in Example 1.
[0071] Step 2: Preparation of prepolymer The steps are the same as those in "Preparation of Prepolymer" in Example 1.
[0072] Step 3: Add additives The procedure is the same as the "addition of adjuvants" step in Example 1.
[0073] Step 4: Obtain the finished product After adding the additives, end-capped isocyanate and deionized water are added to the reactor. The temperature inside the reactor is controlled at 45°C, and the mixture is stirred for 13 minutes at a stirring speed of 900 rpm. Then, the temperature inside the reactor is raised to 65°C and stirred for 22 minutes. Finally, the temperature is lowered to room temperature, and the mixture is stirred under vacuum for 13 minutes to obtain the final product.
[0074] Example 4: Performance Testing and Comparative Analysis The simulated cake shaping sealants obtained in Examples 1, 2, 3, and Comparative Example 1 were tested for indicators such as setting time, 30-day deformation rate, yellowing index after 1000 hours of UV aging, and migration of harmful substances. 1. Setting time: The time from completion of shaping the standard butter pattern by hand to its stable shape (no collapse). 2. 30-day deformation rate: The change rate of pattern height after 30 days at room temperature (deformation rate = (initial height - 30-day height) / initial height × 100%).
[0075] 3. UV aging yellowing index: The UV aging test was conducted for 1000 hours according to the method in GB / T 16422.3-2022.
[0076] 4. Hazardous substance migration: Tested according to the method in GB 4806.1-2016.
[0077] Table 1 As shown in Table 1, the sealant prepared by this invention has a setting time of 4-5 minutes, a deformation rate of 1.2-1.8% after 30 days, a yellowing index ΔE of 1.3-1.4 after 1000 hours of UV aging, and a harmful substance migration amount of less than 0.009 mg / kg. This indicates that the sealant for shaping simulated cakes prepared by this invention has excellent characteristics such as short setting time, low deformation rate after 30 days, low yellowing index after 1000 hours of UV aging, and low harmful substance migration.
[0078] Obviously, there are many other possible implementation methods under the concept of this invention. It should be stated here that any changes made under the inventive concept of this invention will fall within the protection scope of this invention.
Claims
1. A special sealant for shaping simulated cakes, characterized in that: The sealant, by weight, comprises the following raw materials: 60-75 parts of α,ω-dihydroxypolydimethylsiloxane, 5-10 parts of methyltributanone oxime silane, 0.1-0.5 parts of catalyst, 3-8 parts of composite regulator, 5-15 parts of food-grade white oil, 1-3 parts of γ-aminopropyltriethoxysilane, 4-8 parts of nano-calcium carbonate-supported end-capped isocyanate, and 0.5-2 parts of deionized water; The composite regulator is obtained by mixing modified nano-silica with antioxidant 1010; the modified nano-silica is obtained by modifying silica with silane coupling agent KH550; The nano-calcium carbonate-loaded end-capped isocyanate is obtained by ultrasonically cleaning nano-calcium carbonate with dilute hydrochloric acid solution to obtain pretreated nano-calcium carbonate; toluene and pretreated nano-calcium carbonate are mixed and ultrasonically dispersed; end-capped isocyanate is added and reacted to obtain nano-calcium carbonate-loaded end-capped isocyanate. The catalyst is dibutyltin dilaurate.
2. The preparation method of the simulated cake shaping sealant according to claim 1, characterized in that: The process includes the preparation of composite regulators, the preparation of nano-calcium carbonate-supported end-capped isocyanate, the preparation of prepolymers, the addition of additives, and the preparation of the finished product. Preparation of the composite regulator: Modified nano-silica and antioxidant 1010 are mixed evenly to obtain the composite regulator; Preparation of the nano-calcium carbonate-supported end-capped isocyanate: nano-calcium carbonate is ultrasonically cleaned with dilute hydrochloric acid solution, washed, and dried to obtain pretreated nano-calcium carbonate; toluene and pretreated nano-calcium carbonate are mixed and ultrasonically dispersed; end-capped isocyanate is added, the mixture is heated, nitrogen gas is purged for protection, the reaction is stirred, and vacuum dried to obtain nano-calcium carbonate-supported end-capped isocyanate. Preparation of the prepolymer: α,ω-dihydroxypolydimethylsiloxane and food-grade white oil are added to a reaction vessel and stirred; a catalyst and methyltributanone oxime silane are added, the temperature is raised, and the mixture is kept warm and stirred to form a prepolymer; The addition of auxiliary agents: the composite regulator and γ-aminopropyltriethoxysilane are added to the reactor containing the prepolymer, the stirring speed of the reactor is increased, the vacuum degree is adjusted, and stirring is performed. The finished product is obtained by adding the additives, then adding nano-calcium carbonate-loaded end-capped isocyanate and deionized water to the reactor and stirring; heating and stirring while maintaining the temperature; cooling to room temperature and stirring under vacuum to obtain the finished product.
3. The preparation method of the simulated cake shaping sealant according to claim 2, characterized in that: In the preparation steps of the composite regulator, the mass ratio of modified nano silica to antioxidant 1010 is (2-5):(1-3).
4. The preparation method of the simulated cake shaping sealant according to claim 2, characterized in that: In the preparation steps of the composite regulator, the modified nano-silica is prepared by using silane coupling agent KH-550 as the modifier, with a mass ratio of silane coupling agent KH-550 to silica of (1-3):
20. The preparation method is as follows: nano-silica is dispersed in anhydrous ethanol; silane coupling agent KH-550 is added, and the mixture is stirred for 2-4 hours at a temperature of 60-80℃; after drying, modified nano-silica is obtained.
5. The preparation method of the simulated cake shaping sealant according to claim 2, characterized in that: In the preparation step of the end-capped isocyanate supported on nano-calcium carbonate, the nano-calcium carbonate has a particle size of 20-50 nm; and the concentration of the dilute hydrochloric acid solution is 0.4-0.6 wt%.
6. The preparation method of the simulated cake shaping sealant according to claim 2, characterized in that: In the preparation step of the nano-calcium carbonate-supported end-capped isocyanate, the mass ratio of the nano-calcium carbonate, dilute hydrochloric acid solution, toluene, and end-capped isocyanate is 1:(15-25):(1.5-3):(0.9-1.1).
7. The preparation method of the simulated cake shaping sealant according to claim 2, characterized in that: In the preparation step of the nano-calcium carbonate-supported end-capped isocyanate, the ultrasonic dispersion frequency is 30-50 kHz.
8. The preparation method of the simulated cake shaping sealant according to claim 2, characterized in that: Preparation of the prepolymer: α,ω-dihydroxypolydimethylsiloxane and food-grade white oil are added to a reactor. The temperature inside the reactor is set to 25-30℃, the stirring speed is 300-500 rpm, and the mixture is stirred for 10-15 minutes. A catalyst and methyltributanone oxime silane are added to the reactor, the temperature is raised to 40-50℃, and the mixture is kept at this temperature and stirred for 20-30 minutes to form the prepolymer.
9. The preparation method of the simulated cake shaping sealant according to claim 2, characterized in that: The added additives are: the composite regulator and γ-aminopropyltriethoxysilane are added to the prepolymer, the stirring speed is controlled at 800-1000 rpm, the vacuum degree is -0.08 to -0.09 MPa, and the mixture is stirred for 30-40 minutes.
10. The method for preparing a special sealant for shaping simulated cakes according to claim 2, characterized in that: The finished product is obtained as follows: After adding the additives, nano-calcium carbonate-loaded end-capped isocyanate and deionized water are added to the reactor. The temperature inside the reactor is controlled at 40-50℃, and the mixture is stirred for 10-15 minutes at a stirring speed of 800-1000 rpm. Then, the temperature inside the reactor is raised to 130-150℃ and kept at this temperature while stirring for 20-25 minutes. Finally, the temperature is lowered to room temperature and vacuum stirred for 10-15 minutes to obtain the finished product.