Fluorine-containing hyperbranched polysiloxane modified resin and preparation method thereof, and unvulcanized silica gel soft film and preparation method thereof

Abstract

The invention provides fluorine-containing hyperbranched polysiloxane modified resin and a preparation method thereof as well as an unvulcanized silica gel soft film and a preparation method thereof, and belongs to the field of silica gel molds. After the fluorine-containing hyperbranched siloxane is introduced, the fluorine-containing hyperbranched siloxane is large in size and higher in polarity than methyl, the regular spiral structure of a main chain can be broken, close packing between molecular chains is reduced, crystallization driving force is reduced, shrinkage caused by crystallization is inhibited, and it is guaranteed that in the preparation process of parts with complex structures formed by the composite material, the specific surface area of the composite material is increased; and the final part tolerance is small. The fluorine-containing hyperbranched polysiloxane can improve the entanglement density of a molecular chain and limit the free contraction movement of the vulcanized molecular chain, and meanwhile, the fluorine-containing hyperbranched chain segment can absorb energy through deformation under the action of external force, so that the tear toughness, tensile strength and reusability of the mold are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of silicone molds, specifically to a fluorinated hyperbranched polysiloxane modified resin and its preparation method, and an uncured silicone soft film and its preparation method. Background Technology

[0002] Uncured silicone rubber PVC film is an uncured silicone rubber roll (sheet) material suitable for manufacturing large-size pressure equalizing plates and various complex-shaped molds. PVC film made from this silicone rubber can provide uniform pressure distribution in autoclave processes, allowing parts to achieve the same surface quality on the vacuum bag side as on the molded side.

[0003] The immature formulation and poor process applicability of traditional uncured silicone rubber films result in large differences in local mechanical properties of the roll material. After subsequent curing, problems such as insufficient tensile strength and fluctuations in elongation at break are likely to occur, which cannot meet the requirements of high-precision applications. Summary of the Invention

[0004] This invention provides a fluorinated hyperbranched polysiloxane modified resin and its preparation method, as well as an uncured silicone soft film and its preparation method. The uncured silicone soft film of this invention has significantly improved tear resistance and tensile strength after curing, and the cured silicone soft film has smaller final part tolerances and shrinkage, which can meet the requirements of high-precision applications.

[0005] This invention provides a fluorinated hyperbranched polysiloxane modified resin having the structural formula shown in Formula I: Formula I; In Formula I It is -O-CH3; in formula I, R simultaneously includes -CH2CH2CF3 and has the structure shown in formula II: Formula II.

[0006] This invention also provides a method for preparing the fluorinated hyperbranched polysiloxane modified resin described in the above technical solution, comprising the following steps: (3,3,3-trifluoropropyl)trimethylsilane, tetraethyl orthosilicate, water and alcohol solvent were mixed and subjected to transesterification to obtain hyperbranched polysiloxane; The structural formula of the hyperbranched polysiloxane is shown in Formula 1: Formula 1; In Equation 1, R includes -CH2-CH2-; The hyperbranched polysiloxane, vinyl silicone oil, D4 (octamethylcyclotetrasiloxane), and alkaline catalyst are mixed and then subjected to polymerization and enzyme deactivation reactions in sequence to obtain the fluorinated hyperbranched polysiloxane modified resin.

[0007] Preferably, the molar ratio of (3,3,3-trifluoropropyl)trimethylsilane to tetraethyl orthosilicate is 4:3.

[0008] Preferably, the transesterification reaction is carried out at a temperature of 60-70°C for 6-8 hours.

[0009] Preferably, the alkaline catalyst comprises tetramethylammonium hydroxide; the amount of the alkaline catalyst is 0.5 to 1.5% of the amount of the hyperbranched polysiloxane.

[0010] Preferably, the molar ratio of the hyperbranched polysiloxane to the vinyl silicone oil is 1:10~40; The molar ratio of the hyperbranched polysiloxane to D4 (octamethylcyclotetrasiloxane) is 20~50:1.

[0011] Preferably, the polymerization reaction is carried out at a temperature of 105~110℃ for 8~12 hours.

[0012] The present invention also provides an uncured silicone rubber film, comprising, by weight, the following raw materials: 80-90 parts of fluorinated hyperbranched polysiloxane modified resin, 10-30 parts of filler, 1-3 parts of crosslinking agent, 0-5 parts of catalyst, and 1-5 parts of antioxidant; The fluorinated hyperbranched polysiloxane modified resin is the fluorinated hyperbranched polysiloxane modified resin described in the above technical solution or the fluorinated hyperbranched polysiloxane modified resin prepared by the preparation method described in the above technical solution.

[0013] Preferably, the filler includes one or more of calcium carbonate, silica powder, iron oxide, titanium dioxide, fumed silica, boron nitride, titanium dioxide, and iron hydroxide. The crosslinking agent includes one or more of bis(2,5-diphenyl) peroxide, DCP, and DCBP; The catalyst comprises one or both of dibutyltin dilaurate and vinyl platinum complex.

[0014] The antioxidant includes one or both of iron oxide and cerium dioxide.

[0015] The present invention also provides a method for preparing the uncured silicone soft film described in the above technical solution, comprising the following steps: The raw materials for the uncured silicone rubber film are mixed and then calendered to obtain the uncured silicone rubber film.

[0016] Methylsiloxane backbones have a highly ordered helical structure. During vulcanization, the molecular chains are easily rearranged by van der Waals forces, leading to crystallization tendency and shrinkage. This invention introduces fluorinated hyperbranched siloxanes, which are larger in volume and more polar than methyl, breaking the ordered helical structure of the backbone, reducing the close packing between molecular chains, lowering the crystallization driving force, and thus inhibiting shrinkage caused by crystallization. This ensures that the composite material, in the process of manufacturing parts with complex structures, has the characteristics of small tolerances in the final part. Fluorinated hyperbranched polysiloxanes can increase the entanglement density of molecular chains, restrict the free contraction movement of molecular chains after vulcanization, and at the same time, under the influence of... Under external force, fluorinated hyperbranched segments can absorb energy through deformation, significantly improving the tear resistance, tensile strength, and reusability of the mold. The introduction of fluorinated hyperbranched polysiloxane segments can regulate the uniformity of vinyl groups (crosslinking active sites) in the raw rubber, avoiding excessively dense or sparse local crosslinking. This results in a more regular three-dimensional network structure after vulcanization, more uniform stress transmission within the material, and reduced uneven shrinkage caused by localized stress release, indirectly improving product dimensional stability. The introduction of fluorinated groups significantly improves the thermal stability and chemical inertness of polysiloxanes, while reducing surface energy, endowing the material with excellent hydrophobic and oleophobic properties. The strong electronegativity of fluorine atoms enhances the polarity of the molecular chain, further improving compatibility with other polar components. Furthermore, the accumulation of fluorinated groups on the material surface forms a protective layer, effectively blocking the intrusion of external moisture and corrosive media, slowing down the aging process, extending the product's service life, and ensuring efficient demolding performance in complex parts manufacturing processes. Detailed Implementation

[0017] This invention provides a fluorinated hyperbranched polysiloxane modified resin having the structural formula shown in Formula I: Formula I; In Formula I It is -O-CH3; in formula I, R simultaneously includes -CH2CH2CF3 and has the structure shown in formula II: Formula II.

[0018] This invention provides a method for preparing the fluorinated hyperbranched polysiloxane modified resin described in the above technical solution, comprising the following steps: (3,3,3-trifluoropropyl)trimethylsilane, tetraethyl orthosilicate, water and alcohol solvent were mixed and subjected to transesterification to obtain hyperbranched polysiloxane; The structural formula of the hyperbranched polysiloxane is shown in Formula 1: Equation 1; R in Equation 1 includes -CH2-CH2-; The hyperbranched polysiloxane, vinyl silicone oil, D4 (octamethylcyclotetrasiloxane), and alkaline catalyst are mixed and then subjected to polymerization and enzyme deactivation reactions in sequence to obtain the fluorinated hyperbranched polysiloxane modified resin.

[0019] This invention involves mixing (3,3,3-trifluoropropyl)trimethylsilane, tetraethyl orthosilicate, water, and an alcohol solvent to carry out an ester exchange reaction to obtain hyperbranched polysiloxane.

[0020] In this invention, the molar ratio of (3,3,3-trifluoropropyl)trimethylsilane to tetraethyl orthosilicate is preferably 4:3.

[0021] In this invention, the molar ratio of tetraethyl orthosilicate to water is preferably 1:1 to 2.5, and in specific embodiments of this invention it can be 1:1.5 or 1:2.

[0022] In this invention, the volume ratio of water to alcohol solvent is preferably 1:1 to 4.5, and in specific embodiments of this invention it can be 1:2, 1:3 or 1:4.

[0023] In this invention, the temperature of the transesterification reaction is preferably 60~70℃ and the time is preferably 6~8h. In a specific embodiment of this invention, the temperature of the transesterification reaction can be 65℃ and the time can be 6.5h, 7h or 7.5h.

[0024] The equation for the transesterification reaction is shown below: After the transesterification reaction, the present invention preferably cools the product obtained from the transesterification reaction to room temperature and then dries it.

[0025] After obtaining the hyperbranched polysiloxane, the present invention mixes the hyperbranched polysiloxane, vinyl silicone oil, D4 (octamethylcyclotetrasiloxane) and alkaline catalyst, and then carries out polymerization and enzyme deactivation reactions in sequence to obtain the fluorinated hyperbranched polysiloxane modified resin.

[0026] In this invention, the amount of the alkaline catalyst is 0.5-1.5% of the amount of the hyperbranched polysiloxane, and in specific embodiments of this invention it can be 0.8%, 1% or 1.2%; the alkaline catalyst preferably includes tetramethylammonium hydroxide.

[0027] In this invention, the molar ratio of the hyperbranched polysiloxane to the vinyl silicone oil is preferably 1:10 to 40, and in specific embodiments of this invention it can be 1:15, 1:20, 1:25, 1:30 or 1:35.

[0028] In this invention, the molar ratio of the hyperbranched polysiloxane to D4 (octamethylcyclotetrasiloxane) is preferably 20-50:1, and in specific embodiments of this invention, it can be 25:1, 30:1, 35:1, 40:1 or 45:1.

[0029] In this invention, the preferred temperature of the polymerization reaction is 105~110℃, and the preferred time is 8~12h. In specific embodiments of this invention, the temperature of the polymerization reaction can be 106℃, 107℃, 108℃ or 109℃, and the time can be 9h, 10h or 11h.

[0030] Polymerization reactions can occur according to the following equations: In this invention, the temperature of the enzyme-breaking reaction is preferably 135~140℃, and the time is preferably 1~2h. In specific embodiments of this invention, the temperature of the enzyme-breaking reaction can be 136℃, 137℃, 138℃ or 139℃, and the time can be 1.5h.

[0031] The role of enzyme deactivation is to deactivate the catalyst.

[0032] After the enzyme-breaking reaction, the present invention preferably removes the monomers from the product obtained by the enzyme-breaking reaction and then cools it to room temperature.

[0033] The present invention also provides an uncured silicone rubber film, comprising, by weight, the following raw materials: 80-90 parts of fluorinated hyperbranched polysiloxane modified resin, 10-30 parts of filler, 1-3 parts of crosslinking agent, 0-5 parts of catalyst, and 1-5 parts of antioxidant; The fluorinated hyperbranched polysiloxane modified resin is the fluorinated hyperbranched polysiloxane modified resin described in the above technical solution or the fluorinated hyperbranched polysiloxane modified resin prepared by the preparation method described in the above technical solution.

[0034] Based on mass parts, the raw materials for the uncured silicone soft film of the present invention include 80-90 parts of fluorinated hyperbranched polysiloxane modified resin, which in specific embodiments of the present invention can be 81, 82, 83, 84, 85, 86, 87, 88 or 89 parts.

[0035] Based on the unit mass parts of the fluorinated hyperbranched polysiloxane modified resin, the raw materials of the uncured silicone soft film of the present invention include 10 to 30 parts of filler. In specific embodiments of the present invention, these can be 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, or 29 parts. The filler preferably includes one or more of calcium carbonate, silica powder, iron oxide, titanium dioxide, fumed silica, boron nitride, titanium dioxide, and iron hydroxide.

[0036] Based on the unit mass parts of the fluorinated hyperbranched polysiloxane modified resin, the raw materials of the uncured silicone soft film of the present invention include 1 to 3 parts of crosslinking agent. In specific embodiments of the present invention, the amount can be 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2.0 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.7 parts, 2.8 parts, or 2.9 parts. The crosslinking agent preferably includes one or more of bis(2,5-diphenyl)peroxide, DCP, and DCBP.

[0037] Based on the unit mass parts of the fluorinated hyperbranched polysiloxane modified resin, the raw materials of the uncured silicone soft film of the present invention include 0 to 5 parts of catalyst, which can be 1 part, 2 parts, 3 parts or 4 parts in specific embodiments of the present invention; the catalyst preferably includes one or two of dibutyltin dilaurate and vinyl platinum complex.

[0038] Based on the unit mass parts of the fluorinated hyperbranched polysiloxane modified resin, the raw materials of the uncured silicone soft film of the present invention include 1 to 5 parts of antioxidant, which can be 2, 3 or 4 parts in specific embodiments of the present invention; the antioxidant preferably includes one or two of iron oxide and cerium dioxide.

[0039] The present invention also provides a method for preparing the uncured silicone soft film described in the above technical solution, comprising the following steps: The raw materials for the uncured silicone rubber film are mixed and then calendered to obtain the uncured silicone rubber film.

[0040] The following detailed descriptions, in conjunction with embodiments, illustrate the fluorinated hyperbranched polysiloxane modified resin and its preparation method, as well as the uncured silicone soft film and its preparation method provided by the present invention. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0041] Example 1 The specific preparation method of fluorinated hyperbranched polysiloxane modified resin is as follows: 1. Preparation of fluorinated hyperbranched polysiloxanes 0.32 mol of (3,3,3-trifluoropropyl)trimethylsilane and tetraethyl orthosilicate (the molar ratio of (3,3,3-trifluoropropyl)trimethylsilane to tetraethyl orthosilicate was 4:3) were added to a reaction flask, along with a mixture of 10 mL of distilled water and 10 mL of anhydrous ethanol. The mixture was stirred for 30 min, heated to 60 °C, and reacted for 6 h. After cooling to room temperature, the mixture was dried for 24 h to obtain hyperbranched polysiloxane.

[0042] 2. Preparation of fluorinated hyperbranched polysiloxane modified resin 0.1 mol of fluorinated hyperbranched polysiloxane, 1 mol of vinyl silicone oil, 5 mol of D4 (octamethylcyclotetrasiloxane) and 1 g of tetramethylammonium hydroxide were mixed and reacted at a temperature of 105-110℃ for 9 h. After the reaction was completed, the temperature was raised to 135-140℃ and kept at this temperature for 2 h to carry out the enzyme-breaking reaction. Unreacted monomers in the system were removed under vacuum and the mixture was cooled to room temperature to obtain raw rubber.

[0043] The composition of the fluorinated hyperbranched polysiloxane-modified uncured silicone rubber roll is as follows (parts by weight): The mixture contains 80 parts of fluorinated hyperbranched polysiloxane modified resin, 3 parts of crosslinking agent (DBPH), 2 parts of catalyst (dibutyltin dilaurate), 20 parts of filler (silicon micropowder), and 5 parts of antioxidant (ferric hydroxide).

[0044] The preparation method of fluorinated hyperbranched polysiloxane-modified uncured silicone rubber roll material includes the following steps: Fluorinated hyperbranched polysiloxane modified resin, crosslinking agent, catalyst, filler, and antioxidant are placed in a mixing mill and kneaded at room temperature and a pressure of 5 kg / cm². 2 Stirring under these conditions ensures that the mixture is evenly dispersed during the mixing process until it is uniformly mixed.

[0045] The mixed rubber compound is transferred to an atmospheric pressure continuous winding film production device, and along with the PE carrier layer, an uncured POSS-based modified silicone rubber roll with a thickness of 1.6 mm is laminated at room temperature.

[0046] Example 2 Fluorine-containing hyperbranched polysiloxane-modified uncured silicone rubber rolls, by mass parts, consist of: Example 1: 80 parts of fluorinated hyperbranched polysiloxane modified resin, 3 parts of crosslinking agent (DBPH), 2 parts of catalyst (dibutyltin dilaurate), 30 parts of filler (silicon micropowder), and 5 parts of antioxidant (ferric hydroxide).

[0047] The preparation method of fluorinated hyperbranched polysiloxane-modified uncured silicone rubber rolls includes the following steps: Fluorinated hyperbranched polysiloxane modified resin, crosslinking agent, catalyst, filler, and antioxidant are placed in a mixing mill and kneaded at room temperature and a pressure of 5 kg / cm². 2 Stirring under these conditions ensures that the mixture is evenly dispersed during the mixing process until it is uniformly mixed.

[0048] The mixed rubber compound is transferred to an atmospheric pressure continuous winding film production device, and along with the PE carrier layer, an uncured POSS-based modified silicone rubber roll with a thickness of 1.6 mm is laminated at room temperature.

[0049] Example 3 Fluorine-containing hyperbranched polysiloxane-modified uncured silicone rubber rolls, by mass parts, consist of: Example 1: 80 parts of fluorinated hyperbranched polysiloxane modified resin, 3 parts of crosslinking agent (DBPH), 2 parts of catalyst (n-butyl titanate), 20 parts of filler (silica powder), and 5 parts of antioxidant (ferric hydroxide).

[0050] The preparation method of fluorinated hyperbranched polysiloxane-modified uncured silicone rubber rolls includes the following steps: Fluorinated hyperbranched polysiloxane modified resin, crosslinking agent, catalyst, filler, and antioxidant are placed in a mixing mill and kneaded at room temperature and a pressure of 5 kg / cm². 2 Stirring under these conditions ensures that the mixture is evenly dispersed during the mixing process until it is uniformly mixed.

[0051] The mixed rubber compound is transferred to an atmospheric pressure continuous winding film production device, and along with the PE carrier layer, an uncured POSS-based modified silicone rubber roll with a thickness of 1.6 mm is laminated at room temperature.

[0052] Example 4 Example 1: Fluorine-containing hyperbranched polysiloxane-modified uncured silicone rubber roll, with the following components by mass parts: The mixture contains 80 parts of fluorinated hyperbranched polysiloxane modified resin, 3 parts of crosslinking agent (DBPH), 20 parts of filler (silica powder), and 5 parts of antioxidant (ferric hydroxide).

[0053] The preparation method of fluorinated hyperbranched polysiloxane-modified uncured silicone rubber rolls includes the following steps: Fluorinated hyperbranched polysiloxane modified resin, crosslinking agent, catalyst, filler, and antioxidant are placed in a mixing mill and kneaded at room temperature and a pressure of 5 kg / cm². 2 Stirring under these conditions ensures that the mixture is evenly dispersed during the mixing process until it is uniformly mixed.

[0054] The mixed rubber compound is transferred to an atmospheric pressure continuous winding film production device, and along with the PE carrier layer, an uncured POSS-based modified silicone rubber roll with a thickness of 1.6 mm is laminated at room temperature.

[0055] Example 5 Fluorine-containing hyperbranched polysiloxane-modified uncured silicone rubber rolls, by mass parts, consist of: Example 1: 80 parts of fluorinated hyperbranched polysiloxane modified resin, 3 parts of crosslinking agent (DBPH), 2 parts of catalyst (dibutyltin dilaurate), 10 parts of filler (silicon micropowder), and 5 parts of antioxidant (ferric hydroxide).

[0056] The preparation method of fluorinated hyperbranched polysiloxane-modified uncured silicone rubber rolls includes the following steps: Fluorinated hyperbranched polysiloxane modified resin, crosslinking agent, catalyst, filler, and antioxidant are placed in a mixing mill and kneaded at room temperature and a pressure of 5 kg / cm². 2 Stirring under these conditions ensures that the mixture is evenly dispersed during the mixing process until it is uniformly mixed.

[0057] The mixed rubber compound is transferred to an atmospheric pressure continuous winding film production device, and along with the PE carrier layer, an uncured POSS-based modified silicone rubber roll with a thickness of 1.6 mm is laminated at room temperature.

[0058] Example 6 Fluorine-containing hyperbranched polysiloxane-modified uncured silicone rubber rolls, by mass parts, consist of: Example 1: 80 parts of fluorinated hyperbranched polysiloxane modified resin, 3 parts of crosslinking agent (DBPH), 2 parts of catalyst (tetrabutyl titanate), 10 parts of filler (silica powder), and 5 parts of antioxidant (ferric hydroxide).

[0059] The preparation method of fluorinated hyperbranched polysiloxane-modified uncured silicone rubber rolls includes the following steps: Fluorinated hyperbranched polysiloxane modified resin, crosslinking agent, catalyst, filler, and antioxidant are placed in a mixing mill and kneaded at room temperature and a pressure of 5 kg / cm². 2 Stirring under these conditions ensures that the mixture is evenly dispersed during the mixing process until it is uniformly mixed.

[0060] The mixed rubber compound is transferred to an atmospheric pressure continuous winding film production device, and along with the PE carrier layer, an uncured POSS-based modified silicone rubber roll with a thickness of 1.6 mm is laminated at room temperature.

[0061] Test Example 1 Examples 1-6 above were tested and cured using an autoclave or oven under the following conditions: 175°C, 0.3 MPa, 2 hours, with a heating / cooling rate of 3°C / min. The pressure was released only after the temperature dropped below 60°C. Hardness was tested according to the standard test method for hardness of ASTM D2240, and tensile strength and elongation at break were tested according to the standard test method for tensile properties of ASTM D412, vulcanized rubber and thermoplastic elastomers.

[0062] Shrinkage test: Three graduation lines were marked at each of the transverse and longitudinal directions on uncured silicone rubber rolls modified with fluorinated hyperbranched polysiloxane for dimension measurement (L2). After vulcanization (under the curing conditions described above), the samples were placed in a standard laboratory environment (e.g., temperature 23±2℃, relative humidity 50±5%) for 24 hours to allow for dimensional stabilization. Subsequently, the corresponding dimension (L1) of the conditioned samples was measured using high-precision measuring equipment. Calculate the shrinkage rate: The linear shrinkage rate (C) is calculated using the following formula: C = [(L2 - L1) / L2] × 100% Table 1. Test results of uncured silicone rubber rolls modified with fluorinated hyperbranched polysiloxanes prepared in Examples 1-6

[0063] As can be seen from the data in the examples, the uncured silicone rubber film prepared by introducing fluorinated hyperbranched siloxane to modify silicone rubber resin and then adding other fillers, crosslinking agents, antioxidants and catalysts has a significant improvement in mechanical properties after full curing.

[0064] The introduction of fluorinated hyperbranched siloxanes, with their larger volume and higher polarity than methyl groups, disrupts the regular helical structure of the main chain, reduces the close packing between molecular chains, and lowers the crystallization driving force, thereby inhibiting shrinkage caused by crystallization. This ensures that the composite material, in the process of preparing parts with complex structures, has the characteristics of small tolerances in the final part. Fluorinated hyperbranched polysiloxanes can increase the entanglement density of molecular chains, restrict the free contraction movement of molecular chains after vulcanization, and at the same time, under the action of external forces, the fluorinated hyperbranched segments can absorb energy through deformation, significantly improving the tear resistance, tensile strength, and reusability of the mold.

[0065] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A fluorinated hyperbranched polysiloxane-modified resin, characterized in that, It has the structural formula shown in Equation I: Formula I; In Formula I It is -O-CH3; in formula I, R simultaneously includes -CH2CH2CF3 and has the structure shown in formula II: Formula II.

2. The method for preparing the fluorinated hyperbranched polysiloxane modified resin according to claim 1, characterized in that, Includes the following steps: (3,3,3-trifluoropropyl)trimethylsilane, tetraethyl orthosilicate, water and alcohol solvent were mixed and subjected to transesterification to obtain hyperbranched polysiloxane; The structural formula of the hyperbranched polysiloxane is shown in Formula 1: Formula 1; In Equation 1, R includes -CH2-CH2-; The hyperbranched polysiloxane, vinyl silicone oil, D4 (octamethylcyclotetrasiloxane), and alkaline catalyst are mixed and then subjected to polymerization and enzyme deactivation reactions in sequence to obtain the fluorinated hyperbranched polysiloxane modified resin.

3. The preparation method according to claim 2, characterized in that, The molar ratio of (3,3,3-trifluoropropyl)trimethylsilane to tetraethyl orthosilicate is 4:

3.

4. The preparation method according to claim 2, characterized in that, The transesterification reaction is carried out at a temperature of 60-70°C for 6-8 hours.

5. The preparation method according to claim 2, characterized in that, The alkaline catalyst comprises tetramethylammonium hydroxide; the amount of the alkaline catalyst is 0.5 to 1.5% of the amount of the hyperbranched polysiloxane.

6. The preparation method according to claim 2, characterized in that, The molar ratio of the hyperbranched polysiloxane to the vinyl silicone oil is 1:10~40; The molar ratio of the hyperbranched polysiloxane to D4 (octamethylcyclotetrasiloxane) is 20~50:

1.

7. The preparation method according to claim 2, characterized in that, The polymerization reaction is carried out at a temperature of 105~110℃ for 8~12 hours.

8. An uncured silicone rubber film, characterized in that, By weight, it includes the following raw materials: 80-90 parts of fluorinated hyperbranched polysiloxane modified resin, 10-30 parts of filler, 1-3 parts of crosslinking agent, 0-5 parts of catalyst, and 1-5 parts of antioxidant; The fluorinated hyperbranched polysiloxane modified resin is the fluorinated hyperbranched polysiloxane modified resin according to claim 1 or the fluorinated hyperbranched polysiloxane modified resin prepared by the preparation method according to any one of claims 2 to 7.

9. The uncured silicone rubber film according to claim 8, characterized in that, The filler includes one or more of the following: calcium carbonate, silica powder, iron oxide, titanium dioxide, fumed silica, boron nitride, titanium dioxide, and iron hydroxide. The crosslinking agent includes one or more of bis(2,5-diphenyl) peroxide, DCP, and DCBP; The catalyst comprises one or both of dibutyltin dilaurate and vinyl platinum complex. The antioxidant includes one or both of iron oxide and cerium dioxide.

10. The method for preparing the uncured silicone rubber film according to claim 8 or 9, characterized in that, Includes the following steps: The raw materials for the uncured silicone rubber film are mixed and then calendered to obtain the uncured silicone rubber film.

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