Preparation method of bird repeller vibrating diaphragm

Abstract

The invention discloses a preparation method of a bird repeller vibrating diaphragm, which belongs to the field of material synthesis and comprises synthesis of biphenyl cyano liquid crystal monomers, preparation of hydrogen-containing siloxane macromolecules, synthesis of segmented copolymers and preparation of a biphenyl cyano grafted segmented copolymer bird repeller vibrating diaphragm. The preparation method has the beneficial effects that biphenyl cyano liquid crystal units are grafted to a block copolymer main chain, so that the dielectric constant is improved, and meanwhile, the viscosity loss is reduced. The crosslinking density of a hard segment is improved by adopting acrylate, so that the hard segment and a siloxane soft segment form microphase separation, and the mechanical stability is improved. By designing molecular chain conformation to regulate entropy change and enthalpy change, quick response to an electric field is realized. And a dipole directional arrangement channel and a stress dissipation network are synchronously constructed in a mesoscale, so that the cycle service life is prolonged.

Description

Technical Field

[0001] This invention belongs to the field of materials synthesis, and in particular relates to a method for preparing a bird deterrent diaphragm. Background Technology

[0002] In the field of high-voltage transmission line protection, effectively repelling birds to prevent accidents such as nesting and excrement flashover is crucial. Sound and light bird deterrent devices have become the mainstream method due to their non-harmful nature and wide coverage. The performance of their core component—the diaphragm material—directly determines the sound wave conversion efficiency and the device's bird deterrent effect. New bird deterrent diaphragms must possess excellent electromechanical conversion capabilities, rapid response and low energy loss, as well as long-term reliable large-amplitude deformation capability. However, traditional acrylic or silicone-based dielectric elastomer materials, in pursuit of high dielectric constants to enhance electric field response, often suffer from significant viscoelastic losses and mechanical hysteresis, resulting in low electromechanical conversion efficiency, severe heat generation, slow response, and limited lifespan. This makes it difficult to meet the bird deterrent requirements of efficient, sustained, and high-power sound wave output in the harsh outdoor environment of transmission lines.

[0003] To overcome the aforementioned performance contradictions, this invention proposes a design strategy for bird deterrent diaphragm applications. Summary of the Invention

[0004] The core strategy of this invention lies in using biphenyl cyano liquid crystal units as side links to the block polysiloxane-acrylate copolymer skeleton, providing a high-performance material basis for the core diaphragm component of the acoustic and optical bird deterrent device for power transmission lines, and strongly promoting the industrialization process of acoustic surface bird deterrent technology.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a method for preparing a bird deterrent diaphragm, comprising the following steps: Step S1: Preparation of hydrogen-containing siloxane macromolecules In a beaker, 20 g of polymethylhydrosiloxane and 1.05 eq of glycidyl methacrylate were dissolved in toluene. After sonication for 30 min, the mixture was transferred to a three-necked flask, a platinum catalyst was added, and the mixture was heated to 80 °C in a water bath and stirred for 6 h. The resulting substance was then poured into methanol, allowed to stand and precipitate, and then dried under vacuum at 50 °C for 24 h to obtain a hydrosiloxane macromolecule with methacrylate at the molecular end. Step S2: Synthesis of block copolymers 10g of a hydrogen-containing siloxane macromolecule and 0.14eq of 4-cyano-4-(phenylthiocarbamoylthio)valerate RAFT reagent were placed in a three-necked flask and dissolved in toluene. 0.02g of azobisisobutyronitrile (AIBN) was added, and the temperature was adjusted to 70℃ for 8h. After the reaction was completed, the product was transferred to a methanol solution and allowed to stand for 30min to precipitate. The volume ratio of methanol to water in the methanol solution was 8:2. The product was dried under vacuum at 50℃ for 24h to obtain the precursor. Then, 5g of the precursor and 20g of butyl acrylate were weighed and dissolved in N,N-dimethylformamide (DMF). Nitrogen gas was introduced to ensure that oxygen was completely removed, and 0.02g of azobisisobutyronitrile (AIBN) initiator was added. The temperature was raised to 70℃ and the reaction was carried out for 24h. The resulting product was transferred to methanol, allowed to stand for precipitation, and purified by dialysis to obtain the block copolymer. Step S3: Preparation of the diaphragm for the biphenyl cyano-grafted block copolymer bird deterrent The block copolymer was dissolved in a tetrahydrofuran (THF) solution; a dual-terminated silicone oil crosslinking agent and a platinum catalyst were added and reacted at 40°C for 4 hours. The crosslinking process only crosslinked the flexible segments of the block copolymer. The crosslinked polymer solution was then poured onto a polytetrafluoroethylene (PTFE) substrate, and the solvent was evaporated at 60°C for 12 hours. The substrate was then vacuum dried at 60°C for 24 hours to obtain a homogeneous film.

[0006] Furthermore, before the preparation of the hydrogen-containing siloxane macromolecule in step S1, the synthesis of the biphenyl cyano liquid crystal monomer in step S0 must be carried out first. The specific operation method is as follows: Argon gas was introduced into a beaker to dissolve 10 g of 4'-hydroxy-4-cyanobiphenyl in 150 ml of anhydrous THF. The mixture was then placed in an Erlenmeyer flask and cooled to 0 °C in an ice bath. Then, 1.2 eq of acryloyl chloride and 1.5 eq of triethylamine were added dropwise, and the mixture was stirred for 5 min at a speed of 30-50 r / min. The temperature was raised to 25 °C and the reaction was carried out for 12 h. The obtained product was filtered to remove salts, and excess THF was removed by rotary evaporation to obtain a crude product. The crude product was recrystallized three times with ethanol to obtain a white biphenyl cyano liquid crystal monomer.

[0007] Further, step S2 is as follows: 10g of hydrogen-containing siloxane macromolecules and 0.1 eq RAFT reagent are placed in a three-necked flask, dissolved in toluene, and 0.02g of AIBN is added. The temperature is adjusted to 70℃ and the reaction is carried out for 8 hours. After the reaction is completed, the mixture is transferred to a methanol solution and allowed to stand for precipitation for 30 minutes. The volume ratio of methanol to water in the methanol solution is 8:2. The mixture is then dried under vacuum at 50℃ for 24 hours to obtain the precursor. 5g of the precursor, 20g of butyl acrylate, and 5g of biphenyl cyano liquid crystal monomer are weighed and dissolved in DMF. Nitrogen gas is introduced to ensure that oxygen is completely removed. 0.02g of AIBN initiator is added, and the temperature is raised to 70℃ and the reaction is carried out for 24 hours. The resulting product is transferred to methanol, allowed to stand for precipitation, and purified by dialysis to obtain the triblock copolymer.

[0008] Furthermore, platinum electrodes are constructed on both sides of the homogeneous film obtained in step S3, a DC electric field is applied, and the film is kept at a temperature of 1 hour to complete the biphenyl cyano dipole orientation and obtain the biphenyl cyano grafted block copolymer bird deterrent diaphragm.

[0009] Furthermore, the platinum catalyst is a platinum-divinyltetramethyldisiloxane catalyst.

[0010] Furthermore, the preparation method replaces the preparation of the biphenyl cyano grafted block copolymer bird deterrent diaphragm in step S3 with: dissolving the triblock copolymer in a THF solution, adding a dual-terminal hydrogen silicone oil crosslinking agent and a platinum catalyst, reacting at 40°C for 8 hours, casting the crosslinked polymer solution onto a PTFE substrate, evaporating the solvent at 60°C for 12 hours, vacuum drying at 60°C for 24 hours to obtain a homogeneous film, constructing gold electrodes on both sides of the film, applying a DC electric field, and holding at the temperature for 1 hour to complete the biphenyl cyano dipole orientation, thus obtaining the biphenyl cyano grafted block copolymer bird deterrent diaphragm.

[0011] Furthermore, the THF solution described in step S3 is a 20% THF solution by weight.

[0012] Through the above design scheme, the present invention can bring the following beneficial effects: 1. The main chain of the biphenyl cyano liquid crystal grafted block copolymer can improve the dielectric constant while reducing viscous loss.

[0013] 2. By using acrylates to increase the crosslinking density of hard segments, microphase separation is formed with the soft segments of siloxanes, thereby improving mechanical stability.

[0014] 3. Rapid electric field response is achieved by controlling entropy and enthalpy changes through molecular chain conformation design.

[0015] 4. Simultaneously constructing dipole-oriented channels and stress dissipation networks at the mesoscale improves cycle life. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: Figure 1 This is the engineering stress-engineering strain relationship diagram of the present invention; Figure 2 This is a dielectric constant-frequency relationship diagram of the present invention. Detailed Implementation

[0017] The present invention will be further illustrated below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in this technical field.

[0018] Unless otherwise specified, all reagents and materials used in this invention are commercially available.

[0019] Example 1: The preparation method of the novel bird deterrent diaphragm in this example specifically includes the following steps: Step 1: Synthesis of biphenyl cyano liquid crystal monomers Argon gas was introduced into a beaker to dissolve 10g of 4'-hydroxy-4-cyanobiphenyl in 150ml of anhydrous THF. The solution was then placed in an Erlenmeyer flask and cooled to 0°C in an ice bath. 5.57g of acryloyl chloride and 7.79g of triethylamine were then added dropwise. The mixture was stirred for 5min at a speed of 30-50r / min, heated to 25°C, and reacted for 12h. The resulting product was filtered to remove salts, and excess THF was removed by rotary evaporation to obtain a crude product. The crude product was recrystallized three times with ethanol to obtain a white biphenyl cyano liquid crystal monomer.

[0020] The conversion formula between mass (g) and equivalent (eq) is as follows: Mass (g) = Equivalent number (eq) × (Molar mass (g / ) )÷Equivalent factor (n)) Step 2: Preparation of hydrogen-containing siloxane macromolecules In a beaker, 20.0 g of polymethylhydrosiloxane and 1.492 g of glycidyl methacrylate were dissolved in 100 ml of toluene. After sonication for 30 min, the mixture was transferred to a three-necked flask, and 0.35 g of platinum catalyst was added. The mixture was heated to 80 °C in a water bath and stirred for 6 h. The resulting substance was then poured into 300 ml of methanol solution and allowed to stand to precipitate. The precipitate was then dried under vacuum at 50 °C for 24 h to obtain a hydrosiloxane macromolecule with methacrylate at the end.

[0021] Step 3: Synthesis of the triblock copolymer 10g of a hydrogen-containing siloxane macromolecule and 1g of RAFT reagent were placed in a three-necked flask and dissolved in 100ml of toluene. 0.02g of AIBN was added, and the temperature was adjusted to 70℃ for 8h. After the reaction was completed, the mixture was transferred to 200ml of methanol / water (8:2) solution and allowed to stand for 30min to precipitate. The mixture was then vacuum dried at 50℃ for 24h to obtain the precursor. 5g of the obtained precursor was then weighed and dissolved in 100ml of DMF with 20g of butyl acrylate and 5g of biphenyl cyano liquid crystal monomer. Nitrogen gas was purged to ensure complete removal of oxygen. 0.02g of AIBN initiator was added, and the temperature was raised to 70℃ for 24h. The resulting product was transferred to 200ml of methanol solution, allowed to stand for precipitation, and purified by dialysis to obtain the triblock copolymer.

[0022] Among them, RAFT reagent is 4-cyano-4-(phenylthiocarbamoylthio)valerate; AIBN is azobisisobutyronitrile, a commonly used free radical initiator; DMF is N,N-dimethylformamide, a polar aprotic solvent.

[0023] Step 4: Preparation of the diaphragm for the biphenyl cyano-grafted block copolymer bird deterrent The triblock copolymer was dissolved in 20 ml of tetrahydrofuran (20 wt%). 2.38 g of dual-terminated silicone oil crosslinking agent and 0.1 g of platinum catalyst were added, and the reaction was carried out at 40 °C for 4 h to crosslink only the flexible segments of the triblock copolymer. The crosslinked polymer solution was then poured onto a PTFE substrate, and the solvent was evaporated at 60 °C for 12 h. The substrate was then vacuum dried at 60 °C for 24 h to obtain a homogeneous film. Platinum electrodes were constructed on both sides of the film, and a DC electric field was applied for 1 h to complete the biphenyl cyano dipole orientation, thus obtaining a liquid crystal side-chain block copolymer film.

[0024] The PTFE substrate is a printed circuit board substrate made primarily of polytetrafluoroethylene (PTFE), which has excellent electrical properties and chemical stability. Example 2

[0025] Step 1: Synthesis of biphenyl cyano liquid crystal monomers Argon gas was introduced into a beaker to dissolve 10g of 4'-hydroxy-4-cyanobiphenyl in 150ml of anhydrous THF. The solution was then placed in an Erlenmeyer flask and cooled to 0°C in an ice bath. 5.57g of acryloyl chloride and 7.79g of triethylamine were then added dropwise. The mixture was stirred for 5min at a speed of 30-50r / min, heated to 25°C, and reacted for 12h. The resulting product was filtered to remove salts, and excess THF was removed by rotary evaporation to obtain a crude product. The crude product was recrystallized three times with ethanol to obtain a white biphenyl cyano liquid crystal monomer.

[0026] Step 2: Preparation of hydrogen-containing siloxane macromolecules In a beaker, 20.0 g of polymethylhydrosiloxane and 1.492 g of glycidyl methacrylate were dissolved in 100 ml of toluene. After sonication for 30 min, the mixture was transferred to a three-necked flask, and 0.35 g of platinum catalyst was added. The mixture was heated to 80 °C in a water bath and stirred for 6 h. The resulting substance was then poured into methanol and allowed to stand to precipitate. The precipitate was then dried under vacuum at 50 °C for 24 h to obtain a hydrosiloxane macromolecule with methacrylate at the end.

[0027] Step 3: Synthesis of the triblock copolymer 10g of a hydrogen-containing siloxane macromolecule and 1g of RAFT reagent were placed in a three-necked flask and dissolved in 100ml of toluene. 0.02g of AIBN was added, and the temperature was adjusted to 70℃ for 8h. After the reaction was completed, the mixture was transferred to 200ml of methanol / water (8:2) solution and allowed to stand for 30min to precipitate. The mixture was then vacuum dried at 50℃ for 24h to obtain the precursor. 5g of the obtained precursor was weighed and dissolved in 100ml of DMF with 20g of butyl acrylate and 5g of biphenyl cyano liquid crystal monomer. Nitrogen gas was purged to ensure complete removal of oxygen. 0.02g of AIBN initiator was added, and the temperature was raised to 70℃ for 24h. The resulting product was transferred to 200ml of methanol solution, allowed to stand for precipitation, and purified by dialysis to obtain the triblock copolymer.

[0028] Step 4: Preparation of the diaphragm for the biphenyl cyano-grafted block copolymer bird deterrent The triblock copolymer was dissolved in 20 ml of tetrahydrofuran (20 wt%). 2.38 g of dual-terminated silicone oil crosslinking agent and 0.1 g of platinum catalyst were added, and the reaction was carried out at 40 °C for 8 h. The crosslinked polymer solution was then poured onto a PTFE substrate, and the solvent was evaporated at 60 °C for 12 h. The substrate was then vacuum dried at 60 °C for 24 h to obtain a homogeneous film. Gold electrodes were deposited on both sides of the film, and a DC electric field was applied. The film was then kept at this temperature for 1 h to complete the biphenyl cyano dipole orientation, thus obtaining the biphenyl cyano grafted block copolymer bird deterrent diaphragm. Example 3

[0029] Step 1: Preparation of hydrogen-containing siloxane macromolecules In a beaker, 20.0 g of polymethylhydrosiloxane and 1.492 g of glycidyl methacrylate were dissolved in 100 ml of toluene. After sonication for 30 min, the mixture was transferred to a three-necked flask, and 0.35 g of platinum catalyst was added. The mixture was heated to 80 °C in a water bath and stirred for 6 h. The resulting substance was then poured into methanol and allowed to stand to precipitate. The precipitate was then dried under vacuum at 50 °C for 24 h to obtain a hydrosiloxane macromolecule with methacrylate at the end.

[0030] Step 2: Synthesis of block copolymers 10g of a hydrogen-containing siloxane macromolecule and 1g of RAFT reagent were placed in a three-necked flask and dissolved in 100ml of toluene. 0.02g of AIBN was added, and the temperature was adjusted to 70℃ for 8h. After the reaction was completed, the mixture was transferred to 200ml of methanol / water (8:2) solution and allowed to stand for 30min to precipitate. The mixture was then vacuum dried at 50℃ for 24h to obtain the precursor. 5g of the obtained precursor was weighed and dissolved in 100ml of DMF with 20g of butyl acrylate. Nitrogen gas was bubbled through the solution to ensure complete removal of oxygen. 0.02g of AIBN initiator was added, and the temperature was raised to 70℃ for 24h. The resulting product was transferred to 200ml of methanol solution, allowed to stand for precipitation, and purified by dialysis to obtain the block copolymer.

[0031] Step 3: Preparation of the diaphragm for the biphenyl cyano-grafted block copolymer bird deterrent The block copolymer was dissolved in 20 ml of tetrahydrofuran (20 wt%). 2.38 g of dual-terminated silicone oil crosslinking agent and 0.1 g of platinum catalyst were added, and the reaction was carried out at 40 °C for 4 h to crosslink only the flexible segments of the block copolymer. The crosslinked polymer solution was then poured onto a PTFE substrate, and the solvent was evaporated at 60 °C for 12 h. The substrate was then vacuum dried at 60 °C for 24 h to obtain a homogeneous film. Platinum electrodes were constructed on both sides of the film, and a DC electric field was applied. The film was kept at this temperature for 1 h to complete the biphenyl cyano dipole orientation, thus obtaining a liquid crystal side-chain block copolymer film. Example 4

[0032] Step 1: Synthesis of biphenyl cyano liquid crystal monomers Argon gas was introduced into a beaker to dissolve 10g of 4'-hydroxy-4-cyanobiphenyl in 150ml of anhydrous THF. The solution was then placed in an Erlenmeyer flask and cooled to 0°C in an ice bath. 5.57g of acryloyl chloride and 7.79g of triethylamine were then added dropwise. The mixture was stirred for 5min at a speed of 30-50r / min, heated to 25°C, and reacted for 12h. The resulting product was filtered to remove salts, and excess THF was removed by rotary evaporation to obtain a crude product. The crude product was recrystallized three times with ethanol to obtain a white biphenyl cyano liquid crystal monomer.

[0033] Step 2: Preparation of hydrogen-containing siloxane macromolecules In a beaker, 20.0 g of polymethylhydrosiloxane and 1.492 g of glycidyl methacrylate were dissolved in 100 ml of toluene. After sonication for 30 min, the mixture was transferred to a three-necked flask, and 0.35 g of platinum catalyst was added. The mixture was heated to 80 °C in a water bath and stirred for 6 h. The resulting substance was then poured into methanol and allowed to stand to precipitate. The precipitate was then dried under vacuum at 50 °C for 24 h to obtain a hydrosiloxane macromolecule with methacrylate at the end.

[0034] Step 3: Synthesis of the triblock copolymer 10g of a hydrogen-containing siloxane macromolecule and 1g of RAFT reagent were placed in a three-necked flask and dissolved in 100ml of toluene. 0.02g of AIBN was added, and the temperature was adjusted to 70℃ for 8h. After the reaction was completed, the mixture was transferred to 200ml of methanol / water (8:2) solution and allowed to stand for 30min to precipitate. The mixture was then vacuum dried at 50℃ for 24h to obtain the precursor. 5g of the obtained precursor was then weighed and dissolved in DMF with 20g of butyl acrylate and 5g of biphenyl cyano liquid crystal monomer. Nitrogen gas was purged to ensure complete removal of oxygen. 0.02g of AIBN initiator was added, and the mixture was heated to 70℃ for 24h. The resulting product was transferred to 200ml of methanol solution, allowed to stand for precipitation, and purified by dialysis to obtain the triblock copolymer.

[0035] Step 4: Preparation of the diaphragm for the biphenyl cyano-grafted block copolymer bird deterrent The triblock copolymer was dissolved in 20 ml of tetrahydrofuran (20 wt%). 2.38 g of dual-terminated silicone oil crosslinking agent and 0.1 g of platinum catalyst were added, and the reaction was carried out at 40 °C for 4 h to crosslink only the flexible segments of the triblock copolymer. The crosslinked polymer solution was then poured onto a PTFE substrate, and the solvent was evaporated at 60 °C for 12 h. The substrate was then vacuum dried at 60 °C for 24 h to obtain a homogeneous film. Example 5

[0036] A constant tensile displacement rate was applied to the thin film sample of Example 1 using a UTM, and the applied force and the elongation of the sample were recorded simultaneously. By calculating the engineering stress and engineering strain, an engineering stress-engineering strain curve was plotted, from which the elongation at break could be directly read.

[0037] UTM stands for Universal Testing Machine, a core piece of equipment used to test the mechanical properties of materials. It performs various mechanical property tests on a wide range of materials, including metals, plastics, films, fibers, and rubber, such as tensile, compression, bending, shearing, peeling, and tearing tests. The curves are shown below. Figure 1 .

[0038] Analysis of the stress-strain relationship in engineering: Within the range of 50% to 150%, the stress increases almost linearly and rapidly with strain. This is mainly contributed by the combined elasticity of the polysiloxane soft segment and the acrylate hard segment. Under a stress of 2.8 MPa, the slope of the curve decreases significantly. Within the range of 150% to 300%, the stress increases slowly over a long strain range. This is because the introduced dynamic decoupling topology ensures that the deformation of the material is uniformly distributed within a certain range, preventing fracture. After exceeding 300% strain, the stress continues to rise, indicating a significant reinforcement effect between the liquid crystal unit and the polymer backbone, followed by fracture. Example 6

[0039] A broadband dielectric spectrometer was used, and the test environment temperature was controlled at room temperature. The test samples containing and without biphenyl cyano grafted block copolymers were stably placed at the center of the lower electrode of the parallel plate electrode. The upper electrode was slowly lowered, with the contact pressure controlled at 0.5 N. The frequency range was set to... Hz, using a logarithmic sweep frequency mode, applying a 500mV AC sinusoidal voltage, pausing at each frequency point for 5 seconds, and recording the data, the resulting curve is as follows. Figure 2 .

[0040] Analysis of dielectric constant-frequency relationship: The dielectric constant-frequency relationship plot illustrates the material's ability to store charge at different frequencies. Samples containing biphenyl cyano-grafted block copolymers... The dielectric constant of the sample across the entire Hz frequency band is higher than that of the sample without the addition of biphenyl cyano grafted block copolymer, especially in the high-frequency band. The smaller decrease in Hz indicates that the biphenyl cyano-grafted block copolymer effectively improves the dielectric response stability of the material under a wide frequency electric field, which is crucial for the high-frequency performance of acoustic wave conversion efficiency.

[0041] The principle of this invention is: Based on the synergistic mechanism of liquid crystal unit orientation polarization and dynamic decoupling of molecular chains, a dual-functional system of dipole-oriented channels and stress dissipation networks was constructed at the mesoscale by precisely designing the molecular topology of block polysiloxane-acrylate copolymers. Under the influence of an electric field, the strongly polar cyano groups of the biphenyl cyano side chains significantly enhance the dielectric constant. The dynamic decoupling topology, through the free volume effect of the siloxane soft segments and the gradient crosslinking network of the acrylate hard segments, combines the rigid regions of the liquid crystal units with the movement of flexible chains. This allows the material to maintain high elongation at break while reducing viscous loss, overcoming the limitations of traditional dielectric elastomers in achieving high dielectric constant and low viscous loss. This design, through the ΔS-ΔH balance control of the molecular chains, solves the problem of synergistic optimization between electric field response speed and mechanical resilience, providing a core material for acoustic bird deterrent devices that combines rapid response, low energy consumption, and long lifespan.

Claims

1. A method for preparing a diaphragm for a bird deterrent, characterized in that, Follow these steps: Step S1: Preparation of hydrogen-containing siloxane macromolecules In a beaker, 20 g of polymethylhydrosiloxane and 1.05 eq of glycidyl methacrylate were dissolved in toluene. After sonication for 30 min, the mixture was transferred to a three-necked flask, a platinum catalyst was added, and the mixture was heated to 80 °C in a water bath and stirred for 6 h. The resulting substance was then poured into methanol, allowed to stand and precipitate, and then dried under vacuum at 50 °C for 24 h to obtain a hydrosiloxane macromolecule with methacrylate at the molecular end. Step S2: Synthesis of block copolymers 10g of a hydrogen-containing siloxane macromolecule and 0.1eq of 4-cyano-4-(phenylthiocarbamoylthio)valerate RAFT reagent were placed in a three-necked flask and dissolved in toluene. 0.02g of azobisisobutyronitrile (AIBN) was added, and the temperature was adjusted to 70℃ for 8h. After the reaction was completed, the product was transferred to a methanol solution and allowed to stand for 30min to precipitate. The volume ratio of methanol to water in the methanol solution was 8:

2. The product was dried under vacuum at 50℃ for 24h to obtain the precursor. Then, 5g of the precursor and 20g of butyl acrylate were weighed and dissolved in N,N-dimethylformamide (DMF). Nitrogen gas was introduced to ensure that oxygen was completely removed, and 0.02g of azobisisobutyronitrile (AIBN) initiator was added. The temperature was raised to 70℃ and the reaction was carried out for 24h. The resulting product was transferred to methanol, allowed to stand for precipitation, and purified by dialysis to obtain the block copolymer. Step S3: Preparation of the diaphragm for the biphenyl cyano-grafted block copolymer bird deterrent The block copolymer was dissolved in a tetrahydrofuran (THF) solution; a dual-terminated silicone oil crosslinking agent and a platinum catalyst were added and reacted at 40°C for 4 hours. The crosslinking process only crosslinked the flexible segments of the block copolymer. The crosslinked polymer solution was then poured onto a polytetrafluoroethylene (PTFE) substrate, and the solvent was evaporated at 60°C for 12 hours. The substrate was then vacuum dried at 60°C for 24 hours to obtain a homogeneous film.

2. The method for preparing a bird deterrent diaphragm according to claim 1, characterized in that, Before the preparation of the hydrogen-containing siloxane macromolecule in step S1, the synthesis of the biphenyl cyano liquid crystal monomer in step S0 must be carried out first. The specific operation method is as follows: Argon gas was introduced into a beaker to dissolve 10 g of 4'-hydroxy-4-cyanobiphenyl in 150 ml of anhydrous THF. The mixture was then placed in an Erlenmeyer flask and cooled to 0 °C in an ice bath. Then, 1.2 eq of acryloyl chloride and 1.5 eq of triethylamine were added dropwise, and the mixture was stirred for 5 min at a speed of 30-50 r / min. The temperature was raised to 25 °C and the reaction was carried out for 12 h. The obtained product was filtered to remove salts, and excess THF was removed by rotary evaporation to obtain a crude product. The crude product was recrystallized three times with ethanol to obtain a white biphenyl cyano liquid crystal monomer.

3. The method for preparing a bird deterrent diaphragm according to claim 2, characterized in that, Step S2 is as follows: 10g of hydrogen-containing siloxane macromolecules and 0.1 eq RAFT reagent are placed in a three-necked flask, dissolved in toluene, and 0.02g of AIBN is added. The temperature is adjusted to 70℃ and the reaction is carried out for 8 hours. After the reaction is completed, the mixture is transferred to a methanol solution and allowed to stand for 30 minutes to precipitate. The volume ratio of methanol to water in the methanol solution is 8:

2. The mixture is then dried under vacuum at 50℃ for 24 hours to obtain the precursor. 5g of the precursor, 20g of butyl acrylate, and 5g of biphenyl cyano liquid crystal monomer are weighed and dissolved in DMF. Nitrogen gas is introduced to ensure that oxygen is completely removed. 0.02g of AIBN initiator is added, and the temperature is raised to 70℃ and the reaction is carried out for 24 hours. The resulting product is transferred to methanol, allowed to stand for precipitation, and purified by dialysis to obtain the triblock copolymer.

4. The method for preparing a bird deterrent diaphragm according to claim 2, characterized in that: Platinum electrodes are constructed on both sides of the homogeneous film obtained in step S3, a DC electric field is applied, and the film is kept at a temperature of 1 hour to complete the biphenyl cyano dipole orientation and obtain the biphenyl cyano grafted block copolymer bird deterrent diaphragm.

5. The method for preparing a bird deterrent diaphragm according to claim 2, characterized in that: The platinum catalyst is a platinum-divinyltetramethyldisiloxane catalyst.

6. A method for preparing a diaphragm for a bird deterrent, characterized in that: The preparation method replaces the preparation of the biphenyl cyano-grafted block copolymer bird deterrent diaphragm in step S3 of claim 2 with the following: dissolving the triblock copolymer in a THF solution, adding a dual-terminal hydrogen silicone oil crosslinking agent and a platinum catalyst, reacting at 40°C for 8 hours, casting the crosslinked polymer solution onto a PTFE substrate, evaporating the solvent at 60°C for 12 hours, vacuum drying at 60°C for 24 hours to obtain a homogeneous film, constructing gold electrodes on both sides of the film, applying a DC electric field, and holding at the temperature for 1 hour to complete the biphenyl cyano dipole orientation, thus obtaining the biphenyl cyano-grafted block copolymer bird deterrent diaphragm.

7. The method for preparing a bird deterrent diaphragm according to claim 2, characterized in that: The THF solution mentioned in step S3 is a 20% THF solution by weight.

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