Novel preparation method of flexible organic silica gel

Abstract

The invention relates to the technical field of flexible organic silica gel, in particular to a novel preparation method of flexible organic silica gel, which comprises the following steps: S1, preparing raw materials; s2, raw material pretreatment; s3, mixing and stirring; s4, carrying out a cross-linking reaction; s5, heating and reacting; s6, carrying out defoaming treatment; s7, molding and curing; s8, testing flexible organic silica gel; and S9, carrying out post-treatment. The flexibility of the silica gel is effectively improved through the dioctyl phthalate, the hydrogen-containing silicone oil and the polyolefin silicon modified flexibilizer, so that the silica gel is softer, the elasticity is improved, the fumed silica is used as a reinforcing filler, the pulling resistance and mechanical strength of the silica gel are improved, the organic silica gel is prevented from being snapped or broken under external force, and the service life of the silica gel is prolonged. The heat resistance of the silica gel is improved through the nano titanium dioxide, the tolerance of the silica gel to a high-temperature environment is enhanced, and the silica gel can still keep stable physical properties in the high-temperature environment.

Description

Technical Field

[0001] The invention relates to the technical field of flexible organic silica gel, in particular to a novel preparation method of flexible organic silica gel. Background Art

[0002] Flexible silicone is a highly flexible silicone material that plays an important role in many fields. It is a material with high elasticity and excellent adhesion properties.

[0003] A Chinese patent discloses a method for preparing organic silica gel (Announcement No. CN116574382A). This patented technology obtains a finished organic silica gel after mixing the above materials. Compared with traditional organic silica gel, this modified organic silica gel effectively reduces the viscosity peak problem and accelerates the curing speed. However, the organic silica gel prepared above uses conventional preparation materials, and the prepared organic silica gel has poor flexibility, tensile strength and mechanical strength. The organic silica gel has poor elasticity and low resilience, and is easily deformed after long-term use. The organic silica gel is easily broken or cracked under external force, which is not conducive to the service life of the organic silica gel. It has a low tolerance to high temperatures and is easily melted at high temperatures, affecting the normal use of the organic silica gel. Therefore, those skilled in the art provide a new method for preparing flexible organic silica gel to solve the problems raised in the above background technology. Summary of the Invention

[0004] The purpose of the present invention is to provide a novel preparation method of flexible organic silica gel to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a novel method for preparing flexible organic silica gel, comprising the following steps:

[0006] S1. Prepare raw materials: prepare 100-120 parts of polydimethylsiloxane, 3-5 parts of hydrogenated silicone oil, 1-2 parts of dioctyl phthalate, 1-2 parts of nano titanium dioxide, 50-80 parts of fumed silica, 1.5-2 parts of polyolefin silicon modified toughening agent, and 0.2-1.5 parts of chloroplatinic acid isopropyl alcohol solution by weight;

[0007] S2. Raw material pretreatment: Take out 100-120 parts of polydimethylsiloxane, 50-80 parts of fumed silica and 1-2 parts of nano-titanium dioxide, vacuum dry the polydimethylsiloxane, surface treat the fumed silica, and disperse the nano-titanium dioxide;

[0008] S3, mixing and stirring: in a three-necked flask equipped with a stirring device, add vacuum-dried polydimethylsiloxane, turn on the stirring device and stir, slowly add 1-2 parts of dioctyl phthalate and 1.5-2 parts of polyolefin silicon-modified toughening agent, continue stirring for 25-30 minutes, so that the dioctyl phthalate, polyolefin silicon-modified toughening agent and polydimethylsiloxane are evenly mixed, slowly add the surface-treated fumed silica into the three-necked flask and stir, and under stirring, slowly add nano-titanium dioxide into the three-necked flask, continue stirring for 1-2 hours, so that the nano-titanium dioxide is evenly distributed in the above solution;

[0009] S4, cross-linking reaction: 3-5 parts of hydrogenated silicone oil are slowly added to the above solution, and refluxed with stirring at a temperature of 100-110° C. for 25-30 minutes. 0.2-1.5 parts of chloroplatinic acid isopropanol solution are dropwise added to the three-necked flask. After the addition is complete, the reaction temperature is raised to 100-110° C. and maintained at this temperature for 1-2 hours. During the reaction, the viscosity change and appearance are observed to determine the degree of cross-linking reaction.

[0010] S5. Heating and reaction: Heat the materials in the three-necked flask to promote dissolution and reaction of the materials. The heating temperature is 50-54°C.

[0011] S6. Degassing treatment: After the cross-linking reaction is completed, the material is transferred to a vacuum container, and the vacuum pump is turned on to make the vacuum degree in the container reach 0.08-0.1 MPa. In the vacuum environment, the bubbles in the silica gel gradually rise and escape. The vacuum state is maintained for 10-20 minutes. During this period, stirring or ultrasonic treatment is used to further promote the discharge of bubbles;

[0012] S7, molding and curing: pour the degassed silicone into a pre-prepared mold and perform compression molding. Place the mold in an oven and cure it at a temperature of 20-25°C for 5-8 hours to fully shape the silicone. Remove the cured silicone from the mold.

[0013] S8. Flexible organic silicone testing: Perform performance testing, elasticity testing, tensile strength testing, and heat resistance testing on the manufactured flexible organic silicone, and record the test data of the flexible organic silicone;

[0014] S9. Post-processing: Grind and polish the flexible organic silicone after production, clean and dry the silicone to remove residual vulcanizer and impurities, and conduct quality inspection on the silicone, including appearance inspection and size measurement, to ensure that it meets relevant standards and requirements.

[0015] As a further solution of the present invention: the hydrogen content of the hydrogenated silicone oil in S1 is 10%, and the platinum content of the chloroplatinic acid isopropanol solution is 6%.

[0016] As a further embodiment of the present invention, the vacuum drying treatment of the polydimethylsiloxane in S2 is as follows: the polydimethylsiloxane is placed in a vacuum drying oven and dried for 1 to 2 hours at a temperature of 100 to 110° C. and a vacuum degree of 0.005 to 0.008 MPa to remove the moisture contained therein;

[0017] The surface treatment of fumed silica comprises the following steps: adding fumed silica to a three-necked flask containing toluene, ultrasonically dispersing the fumed silica for 25 to 30 minutes to uniformly disperse the fumed silica in the toluene solution, filtering, washing, and drying the fumed silica to obtain surface-treated fumed silica. The surface-treated fumed silica can better combine with polydimethylsiloxane to enhance the performance of silica gel. The nano-titanium dioxide dispersion comprises the following steps: adding nano-titanium dioxide to anhydrous ethanol, ultrasonically dispersing the fumed silica for 25 to 30 minutes using an ultrasonic disperser to form a uniform suspension, and storing the suspension for later use.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The novel preparation method of the flexible organic silica gel of the present invention effectively improves the flexibility of the silicone gel by using dioctyl phthalate, hydrogenated silicone oil, and polyolefin silicon modified toughening agent, making it softer and enhancing its elasticity. Fumed silica is used as a reinforcing filler to increase the tensile strength and mechanical strength of the silicone gel, preventing the silicone gel from being broken or cracked by external forces, thereby extending the service life of the silicone gel.

[0020] 2. Nano-titanium dioxide is used to improve the heat resistance of silicone rubber and enhance its tolerance to high temperature environments, so that it can still maintain stable physical properties in high temperature environments. DETAILED DESCRIPTION

[0021] Example 1

[0022] A novel preparation method of flexible organic silica gel, the steps are as follows:

[0023] S1. Prepare raw materials: prepare by weight 100 parts of polydimethylsiloxane, 3 parts of hydrogenated silicone oil, 1 part of dioctyl phthalate, 1 part of nano-titanium dioxide, 50 parts of fumed silica, 1.5 parts of polyolefin silicon-modified toughening agent, and 0.2 parts of chloroplatinic acid isopropanol solution, wherein the hydrogen content of the hydrogenated silicone oil is 10%, and the platinum content of the chloroplatinic acid isopropanol solution is 6%;

[0024] S2. Raw material pretreatment: Take out 100 parts of polydimethylsiloxane, 50 parts of fumed silica and 1 part of nano-titanium dioxide, vacuum dry the polydimethylsiloxane, surface treat the fumed silica, and disperse the nano-titanium dioxide. The vacuum drying process of polydimethylsiloxane is as follows: Place the polydimethylsiloxane in a vacuum drying oven and dry it for 1 to 2 hours at a temperature of 100 to 110°C and a vacuum degree of 0.005 to 0.008 MPa to remove the moisture contained therein; Surface treatment of fumed silica The method comprises the following steps: adding fumed silica to a three-necked flask containing toluene, ultrasonically dispersing the fumed silica for 25 to 30 minutes to uniformly disperse the fumed silica in the toluene solution, filtering, washing, and drying the fumed silica to obtain surface-treated fumed silica. The surface-treated fumed silica can better combine with polydimethylsiloxane to enhance the performance of the silica gel; and dispersing the nano-titanium dioxide as follows: adding the nano-titanium dioxide to anhydrous ethanol, ultrasonically dispersing the fumed silica for 25 to 30 minutes using an ultrasonic disperser to form a uniform suspension, which is then stored for later use.

[0025] S3, mixing and stirring: in a three-necked flask equipped with a stirring device, add vacuum-dried polydimethylsiloxane, turn on the stirring device and stir, slowly add 1 part of dioctyl phthalate and 1.5 parts of polyolefin silicon-modified toughening agent, continue stirring for 25 to 30 minutes, so that the dioctyl phthalate, polyolefin silicon-modified toughening agent and polydimethylsiloxane are evenly mixed, slowly add the surface-treated fumed silica into the three-necked flask and stir, and under stirring, slowly add nano-titanium dioxide into the three-necked flask, continue stirring for 1 to 2 hours, so that the nano-titanium dioxide is evenly distributed in the above solution;

[0026] S4, cross-linking reaction: 3 parts of hydrogenated silicone oil were slowly added to the above solution, and refluxed with stirring at a temperature of 100-110° C. for 25-30 minutes. 0.2 parts of chloroplatinic acid isopropanol solution were dropwise added to the three-necked flask. After the addition was complete, the reaction temperature was raised to 100-110° C. and maintained at this temperature for 1-2 hours. During the reaction, the viscosity change and appearance were observed to determine the degree of cross-linking reaction.

[0027] S5. Heating and reaction: Heat the materials in the three-necked flask to promote dissolution and reaction of the materials. The heating temperature is 50-54°C.

[0028] S6. Degassing treatment: After the cross-linking reaction is completed, the material is transferred to a vacuum container, and the vacuum pump is turned on to make the vacuum degree in the container reach 0.08-0.1 MPa. In the vacuum environment, the bubbles in the silica gel gradually rise and escape. The vacuum state is maintained for 10-20 minutes. During this period, stirring or ultrasonic treatment is used to further promote the discharge of bubbles;

[0029] S7, molding and curing: pour the degassed silicone into a pre-prepared mold and perform compression molding. Place the mold in an oven and cure it at a temperature of 20-25°C for 5-8 hours to fully shape the silicone. Remove the cured silicone from the mold.

[0030] S8. Flexible organic silicone testing: Perform performance testing, elasticity testing, tensile strength testing, and heat resistance testing on the manufactured flexible organic silicone, and record the test data of the flexible organic silicone;

[0031] S9. Post-processing: Grind and polish the flexible organic silicone after production, clean and dry the silicone to remove residual vulcanizer and impurities, and conduct quality inspection on the silicone, including appearance inspection and size measurement, to ensure that it meets relevant standards and requirements.

[0032] Example 2

[0033] A novel preparation method of flexible organic silica gel, the steps are as follows:

[0034] S1. Prepare raw materials: prepare by weight 100 parts of polydimethylsiloxane, 5 parts of hydrogenated silicone oil, 2 parts of dioctyl phthalate, 2 parts of nano-titanium dioxide, 50 parts of fumed silica, 2 parts of polyolefin silicon modified toughening agent, and 1.5 parts of chloroplatinic acid isopropanol solution, wherein the hydrogen content of the hydrogenated silicone oil is 10%, and the platinum content of the chloroplatinic acid isopropanol solution is 6%;

[0035] S2. Raw material pretreatment: Take out 100 parts of polydimethylsiloxane, 50 parts of fumed silica and 2 parts of nano-titanium dioxide, vacuum dry the polydimethylsiloxane, surface treat the fumed silica, and disperse the nano-titanium dioxide. The contents of the vacuum drying of polydimethylsiloxane are as follows: Place the polydimethylsiloxane in a vacuum drying oven and dry it for 1 to 2 hours at a temperature of 100 to 110°C and a vacuum degree of 0.005 to 0.008 MPa to remove the moisture contained therein; the contents of the surface treatment of fumed silica are as follows: The method comprises the following steps: adding fumed silica to a three-necked flask containing toluene, ultrasonically dispersing the fumed silica for 25 to 30 minutes to uniformly disperse the fumed silica in the toluene solution, filtering, washing, and drying the fumed silica to obtain surface-treated fumed silica. The surface-treated fumed silica can better combine with polydimethylsiloxane to enhance the performance of the silica gel; and dispersing the nano-titanium dioxide as follows: adding the nano-titanium dioxide to anhydrous ethanol, ultrasonically dispersing the fumed silica for 25 to 30 minutes using an ultrasonic disperser to form a uniform suspension, which is then stored for later use.

[0036] S3, mixing and stirring: in a three-necked flask equipped with a stirring device, add vacuum-dried polydimethylsiloxane, turn on the stirring device and stir, slowly add 2 parts of dioctyl phthalate and 2 parts of polyolefin silicon-modified toughening agent, continue stirring for 25 to 30 minutes, so that the dioctyl phthalate, polyolefin silicon-modified toughening agent and polydimethylsiloxane are evenly mixed, slowly add the surface-treated fumed silica into the three-necked flask and stir, and under stirring, slowly add nano-titanium dioxide into the three-necked flask, continue stirring for 1 to 2 hours, so that the nano-titanium dioxide is evenly distributed in the above solution;

[0037] S4, cross-linking reaction: 5 parts of hydrogenated silicone oil were slowly added to the above solution, and refluxed with stirring at a temperature of 100-110° C. for 25-30 minutes. 1.5 parts of chloroplatinic acid isopropanol solution were dropwise added to the three-necked flask. After the addition was complete, the reaction temperature was raised to 100-110° C. and maintained at this temperature for 1-2 hours. During the reaction, the viscosity change and appearance were observed to determine the progress of the cross-linking reaction.

[0038] S5. Heating and reaction: Heat the materials in the three-necked flask to promote dissolution and reaction of the materials. The heating temperature is 50-54°C.

[0039] S6. Degassing treatment: After the cross-linking reaction is completed, the material is transferred to a vacuum container, and the vacuum pump is turned on to make the vacuum degree in the container reach 0.08-0.1 MPa. In the vacuum environment, the bubbles in the silica gel gradually rise and escape. The vacuum state is maintained for 10-20 minutes. During this period, stirring or ultrasonic treatment is used to further promote the discharge of bubbles;

[0040] S7, molding and curing: pour the degassed silicone into a pre-prepared mold and perform compression molding. Place the mold in an oven and cure it at a temperature of 20-25°C for 5-8 hours to fully shape the silicone. Remove the cured silicone from the mold.

[0041] S8. Flexible organic silicone testing: Perform performance testing, elasticity testing, tensile strength testing, and heat resistance testing on the manufactured flexible organic silicone, and record the test data of the flexible organic silicone;

[0042] S9. Post-processing: Grind and polish the flexible organic silicone after production, clean and dry the silicone to remove residual vulcanizer and impurities, and conduct quality inspection on the silicone, including appearance inspection and size measurement, to ensure that it meets relevant standards and requirements.

[0043] Example 3

[0044] A novel preparation method of flexible organic silica gel, the steps are as follows:

[0045] S1. Prepare raw materials: prepare by weight 120 parts of polydimethylsiloxane, 3 parts of hydrogenated silicone oil, 1 part of dioctyl phthalate, 1 part of nano-titanium dioxide, 80 parts of fumed silica, 1.5 parts of polyolefin silicon-modified toughening agent, and 0.2 parts of chloroplatinic acid isopropanol solution, wherein the hydrogen content of the hydrogenated silicone oil is 10%, and the platinum content of the chloroplatinic acid isopropanol solution is 6%;

[0046] S2. Raw material pretreatment: Take out 120 parts of polydimethylsiloxane, 80 parts of fumed silica and 1 part of nano-titanium dioxide, vacuum dry the polydimethylsiloxane, surface treat the fumed silica, and disperse the nano-titanium dioxide. The vacuum drying process of polydimethylsiloxane is as follows: Place the polydimethylsiloxane in a vacuum drying oven and dry it for 1 to 2 hours at a temperature of 100 to 110°C and a vacuum degree of 0.005 to 0.008 MPa to remove the moisture contained therein; Surface treatment of fumed silica The method comprises the following steps: adding fumed silica to a three-necked flask containing toluene, ultrasonically dispersing the fumed silica for 25 to 30 minutes to uniformly disperse the fumed silica in the toluene solution, filtering, washing, and drying the fumed silica to obtain surface-treated fumed silica. The surface-treated fumed silica can better combine with polydimethylsiloxane to enhance the performance of the silica gel; and dispersing the nano-titanium dioxide as follows: adding the nano-titanium dioxide to anhydrous ethanol, ultrasonically dispersing the fumed silica for 25 to 30 minutes using an ultrasonic disperser to form a uniform suspension, which is then stored for later use.

[0047] S3, mixing and stirring: in a three-necked flask equipped with a stirring device, add vacuum-dried polydimethylsiloxane, turn on the stirring device and stir, slowly add 1 part of dioctyl phthalate and 1.5 parts of polyolefin silicon-modified toughening agent, continue stirring for 25 to 30 minutes, so that the dioctyl phthalate, polyolefin silicon-modified toughening agent and polydimethylsiloxane are evenly mixed, slowly add the surface-treated fumed silica into the three-necked flask and stir, and under stirring, slowly add nano-titanium dioxide into the three-necked flask, continue stirring for 1 to 2 hours, so that the nano-titanium dioxide is evenly distributed in the above solution;

[0048] S4, cross-linking reaction: 3 parts of hydrogenated silicone oil were slowly added to the above solution, and refluxed with stirring at a temperature of 100-110° C. for 25-30 minutes. 0.2 parts of chloroplatinic acid isopropanol solution were dropwise added to the three-necked flask. After the addition was complete, the reaction temperature was raised to 100-110° C. and maintained at this temperature for 1-2 hours. During the reaction, the viscosity change and appearance were observed to determine the degree of cross-linking reaction.

[0049] S5. Heating and reaction: Heat the materials in the three-necked flask to promote dissolution and reaction of the materials. The heating temperature is 50-54°C.

[0050] S6. Degassing treatment: After the cross-linking reaction is completed, the material is transferred to a vacuum container, and the vacuum pump is turned on to make the vacuum degree in the container reach 0.08-0.1 MPa. In the vacuum environment, the bubbles in the silica gel gradually rise and escape. The vacuum state is maintained for 10-20 minutes. During this period, stirring or ultrasonic treatment is used to further promote the discharge of bubbles;

[0051] S7, molding and curing: pour the degassed silicone into a pre-prepared mold and perform compression molding. Place the mold in an oven and cure it at a temperature of 20-25°C for 5-8 hours to fully shape the silicone. Remove the cured silicone from the mold.

[0052] S8. Flexible organic silicone testing: Perform performance testing, elasticity testing, tensile strength testing, and heat resistance testing on the manufactured flexible organic silicone, and record the test data of the flexible organic silicone;

[0053] S9. Post-processing: Grind and polish the flexible organic silicone after production, clean and dry the silicone to remove residual vulcanizer and impurities, and conduct quality inspection on the silicone, including appearance inspection and size measurement, to ensure that it meets relevant standards and requirements.

[0054] Example 4

[0055] A novel preparation method of flexible organic silica gel, the steps are as follows:

[0056] S1. Prepare raw materials: prepare by weight 120 parts of polydimethylsiloxane, 5 parts of hydrogenated silicone oil, 2 parts of dioctyl phthalate, 2 parts of nano-titanium dioxide, 80 parts of fumed silica, 2 parts of polyolefin silicon-modified toughening agent, and 1.5 parts of chloroplatinic acid isopropanol solution, wherein the hydrogen content of the hydrogenated silicone oil is 10%, and the platinum content of the chloroplatinic acid isopropanol solution is 6%;

[0057] S2. Raw material pretreatment: Take out 120 parts of polydimethylsiloxane, 80 parts of fumed silica and 2 parts of nano-titanium dioxide, vacuum dry the polydimethylsiloxane, surface treat the fumed silica, and disperse the nano-titanium dioxide. The vacuum drying process of polydimethylsiloxane is as follows: Place the polydimethylsiloxane in a vacuum drying oven and dry it for 1 to 2 hours at a temperature of 100 to 110°C and a vacuum degree of 0.005 to 0.008 MPa to remove the moisture contained therein; Surface treatment of fumed silica The method comprises the following steps: adding fumed silica to a three-necked flask containing toluene, ultrasonically dispersing the fumed silica for 25 to 30 minutes to uniformly disperse the fumed silica in the toluene solution, filtering, washing, and drying the fumed silica to obtain surface-treated fumed silica. The surface-treated fumed silica can better combine with polydimethylsiloxane to enhance the performance of the silica gel; and dispersing the nano-titanium dioxide as follows: adding the nano-titanium dioxide to anhydrous ethanol, ultrasonically dispersing the fumed silica for 25 to 30 minutes using an ultrasonic disperser to form a uniform suspension, which is then stored for later use.

[0058] S3, mixing and stirring: in a three-necked flask equipped with a stirring device, add vacuum-dried polydimethylsiloxane, turn on the stirring device and stir, slowly add 2 parts of dioctyl phthalate and 2 parts of polyolefin silicon-modified toughening agent, continue stirring for 25 to 30 minutes, so that the dioctyl phthalate, polyolefin silicon-modified toughening agent and polydimethylsiloxane are evenly mixed, slowly add the surface-treated fumed silica into the three-necked flask and stir, and under stirring, slowly add nano-titanium dioxide into the three-necked flask, continue stirring for 1 to 2 hours, so that the nano-titanium dioxide is evenly distributed in the above solution;

[0059] S4, cross-linking reaction: 5 parts of hydrogenated silicone oil were slowly added to the above solution, and refluxed with stirring at a temperature of 100-110° C. for 25-30 minutes. 1.5 parts of chloroplatinic acid isopropanol solution were dropwise added to the three-necked flask. After the addition was complete, the reaction temperature was raised to 100-110° C. and maintained at this temperature for 1-2 hours. During the reaction, the viscosity change and appearance were observed to determine the progress of the cross-linking reaction.

[0060] S5. Heating and reaction: Heat the materials in the three-necked flask to promote dissolution and reaction of the materials. The heating temperature is 50-54°C.

[0061] S6. Degassing treatment: After the cross-linking reaction is completed, the material is transferred to a vacuum container, and the vacuum pump is turned on to make the vacuum degree in the container reach 0.08-0.1 MPa. In the vacuum environment, the bubbles in the silica gel gradually rise and escape. The vacuum state is maintained for 10-20 minutes. During this period, stirring or ultrasonic treatment is used to further promote the discharge of bubbles;

[0062] S7, molding and curing: pour the degassed silicone into a pre-prepared mold and perform compression molding. Place the mold in an oven and cure it at a temperature of 20-25°C for 5-8 hours to fully shape the silicone. Remove the cured silicone from the mold.

[0063] S8. Flexible organic silicone testing: Perform performance testing, elasticity testing, tensile strength testing, and heat resistance testing on the manufactured flexible organic silicone, and record the test data of the flexible organic silicone;

[0064] S9. Post-processing: Grind and polish the flexible organic silicone after production, clean and dry the silicone to remove residual vulcanizer and impurities, and conduct quality inspection on the silicone, including appearance inspection and size measurement, to ensure that it meets relevant standards and requirements.

[0065] In order to better illustrate the technical effects of the present invention, the following embodiments are described:

[0066] The organic silica gel prepared by the present invention was selected as Examples 1, 2, 3, and 4, and the organic silica gel prepared by a method for preparing organic silica gel disclosed in the patent website (publication date: 2023-08-11, publication number: CN116574382A) was selected as a comparative example; performance tests, elasticity tests, tensile strength tests, and heat resistance tests were performed respectively;

[0067] The performance test is based on the following: the prepared organic silicone sample is made into a strip with a width of 20mm and a thickness of 10mm. One end of the sample is fixed and a certain force is applied to the other end to bend it. The stress changes of the sample at different bending angles are recorded.

[0068] The elasticity test was conducted as follows: the prepared silicone rubber samples were cut into strips with a width of 20 mm and a thickness of 10 mm, and the silicone rubber samples were subjected to tensile and rebound tests using a tensile testing machine;

[0069] The tensile strength test was conducted as follows: the prepared silicone rubber sample was cut into strips with a width of 20 mm and a thickness of 10 mm, and the silicone rubber sample was subjected to a tensile test using a tensile testing machine;

[0070] The heat resistance test is based on the following: The prepared organic silica gel sample is formed into a long strip with a width of 20 mm and a thickness of 10 mm. The organic silica gel sample is tested using a thermogravimetric analyzer. The sample is placed in the crucible of the thermogravimetric analyzer and heated from room temperature to 100°C at a rate of 10°C / min under a nitrogen environment. The change in sample mass with temperature is recorded. The organic silica gel sample is tested using a differential scanning calorimeter, and the change in heat flow of the sample is recorded to determine its melting point.

[0071] Scoring was performed based on the above tests. The scores for the performance test, elasticity test, tensile strength test, and heat resistance test were all 1 to 10 points. The higher the score of the performance test, the better the performance; the higher the score of the elasticity test, the greater the elasticity; the higher the score of the tensile strength test, the stronger the tensile resistance; the higher the score of the heat resistance test, the better the heat resistance. The results are recorded in Table 1.

[0072] Table 1

[0073]

[0074] As can be seen from Table 1, the performance test scores in Example 1, Example 2, Example 3 and Example 4 are all higher than the performance test scores in the comparative example, which shows that the performance of the organic silicone prepared in Example 1, Example 2, Example 3 and Example 4 is better than the organic silicone prepared in the comparative example; the elasticity test scores in Example 1, Example 2, Example 3 and Example 4 are all higher than the elasticity test scores in the comparative example, which shows that the elasticity of the organic silicone prepared in Example 1, Example 2, Example 3 and Example 4 is better than the organic silicone prepared in the comparative example; the tensile strength test scores in Example 1, Example 2, Example 3 and Example 4 are all higher than the tensile strength test scores in the comparative example, which shows that the tensile strength of the organic silicone prepared in Example 1, Example 2, Example 3 and Example 4 is better than the organic silicone prepared in the comparative example; the heat resistance test scores in Example 1, Example 2, Example 3 and Example 4 are all higher than the heat resistance test scores in the comparative example, which shows that the heat resistance of the organic silicone prepared in Example 1, Example 2, Example 3 and Example 4 is better than the organic silicone prepared in the comparative example.

[0075] The above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A novel method for preparing flexible organic silica gel, characterized in that: Here are the steps: S1. Prepare raw materials: prepare 100-120 parts of polydimethylsiloxane, 3-5 parts of hydrogenated silicone oil, 1-2 parts of dioctyl phthalate, 1-2 parts of nano titanium dioxide, 50-80 parts of fumed silica, 1.5-2 parts of polyolefin silicon modified toughening agent, and 0.2-1.5 parts of chloroplatinic acid isopropyl alcohol solution by weight; S2. Raw material pretreatment: Take out 100-120 parts of polydimethylsiloxane, 50-80 parts of fumed silica and 1-2 parts of nano-titanium dioxide, vacuum dry the polydimethylsiloxane, surface treat the fumed silica, and disperse the nano-titanium dioxide; S3, mixing and stirring: in a three-necked flask equipped with a stirring device, add vacuum-dried polydimethylsiloxane, turn on the stirring device and stir, slowly add 1-2 parts of dioctyl phthalate and 1.5-2 parts of polyolefin silicon-modified toughening agent, continue stirring for 25-30 minutes, so that the dioctyl phthalate, polyolefin silicon-modified toughening agent and polydimethylsiloxane are evenly mixed, slowly add the surface-treated fumed silica into the three-necked flask and stir, and under stirring, slowly add nano-titanium dioxide into the three-necked flask, continue stirring for 1-2 hours, so that the nano-titanium dioxide is evenly distributed in the above solution; S4, cross-linking reaction: 3-5 parts of hydrogenated silicone oil are slowly added to the above solution, and refluxed with stirring at a temperature of 100-110° C. for 25-30 minutes. 0.2-1.5 parts of chloroplatinic acid isopropanol solution are dropwise added to the three-necked flask. After the addition is complete, the reaction temperature is raised to 100-110° C. and maintained at this temperature for 1-2 hours. During the reaction, the viscosity change and appearance are observed to determine the degree of cross-linking reaction. S5. Heating and reaction: Heat the materials in the three-necked flask to promote dissolution and reaction of the materials. The heating temperature is 50-54°C. S6. Degassing treatment: After the cross-linking reaction is completed, the material is transferred to a vacuum container, and the vacuum pump is turned on to make the vacuum degree in the container reach 0.08-0.1 MPa. In the vacuum environment, the bubbles in the silica gel gradually rise and escape. The vacuum state is maintained for 10-20 minutes. During this period, stirring or ultrasonic treatment is used to further promote the discharge of bubbles; S7, molding and curing: pour the degassed silicone into a pre-prepared mold and perform compression molding. Place the mold in an oven and cure it at a temperature of 20-25°C for 5-8 hours to fully shape the silicone. Remove the cured silicone from the mold. S8. Flexible organic silicone testing: Perform performance testing, elasticity testing, tensile strength testing, and heat resistance testing on the manufactured flexible organic silicone, and record the test data of the flexible organic silicone; S9. Post-processing: Grind and polish the flexible organic silicone after production, clean and dry the silicone to remove residual vulcanizer and impurities, and conduct quality inspection on the silicone, including appearance inspection and size measurement, to ensure that it meets relevant standards and requirements.

2. The novel preparation method of a flexible organic silica gel according to claim 1, characterized in that: The hydrogen content of the hydrogenated silicone oil in S1 is 10%, and the platinum content of the chloroplatinic acid isopropanol solution is 6%.

3. The novel preparation method of a flexible organic silica gel according to claim 1, characterized in that: The vacuum drying treatment of the polydimethylsiloxane in S2 is as follows: placing the polydimethylsiloxane in a vacuum drying oven, drying it for 1 to 2 hours at a temperature of 100 to 110° C. and a vacuum degree of 0.005 to 0.008 MPa to remove the moisture contained therein; The surface treatment of fumed silica comprises the following steps: adding fumed silica to a three-necked flask containing toluene, ultrasonically dispersing the fumed silica for 25 to 30 minutes to uniformly disperse the fumed silica in the toluene solution, filtering, washing, and drying the fumed silica to obtain surface-treated fumed silica. The surface-treated fumed silica can better bond with polydimethylsiloxane, thereby enhancing the performance of the silica gel. The nano-titanium dioxide dispersion process is as follows: adding nano-titanium dioxide into anhydrous ethanol, and using an ultrasonic disperser to ultrasonically disperse the nano-titanium dioxide for 25 to 30 minutes to form a uniform suspension, which is then stored for later use.

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