CN117089005A - Ultralow dielectric copolymer and preparation method and application thereof - Google Patents

Abstract

The present invention relates to the technical field of ultra-low dielectric material preparation, and in particular to an ultra-low dielectric copolymer and its preparation method and application. In the present invention, a mixed liquid is obtained by mixing hydrocarbon solvents, silicon-containing dienes or derivatives thereof, and 4-methyl-1-pentene, and then sequentially adding cocatalysts and single-active center transition metal catalysts to the mixed liquid. , perform polymerization reaction to obtain ultra-low dielectric copolymer. The dielectric constant of the ultra-low dielectric copolymer prepared by the invention is 1.9~2.4, and the dielectric loss is 0.00001~0.001; the tensile strength of the copolymer is 30~70MPa, the tensile modulus is >2000MPa, and the elongation at break It is 10~90%; the transparency of the copolymer is >88%. The present invention broadens the application range of polycarbosilane.

Description

An ultra-low dielectric copolymer and its preparation method and application

Technical field

The present invention relates to the technical field of ultra-low dielectric material preparation, and in particular to an ultra-low dielectric copolymer and its preparation method and application.

Background technique

With the advent of the intelligent high-frequency communication era (5G/6G), the parasitic effects caused by resistor and capacitor (RC) delays are becoming more and more obvious, directly affecting the performance of the device. The lower the dielectric constant of the interlayer dielectric material used in the device, the lower the signal delay and the higher the signal fidelity. Therefore, it is crucial to develop interlayer materials with ultralow dielectric constant. Generally speaking, interlayer insulating materials with low dielectric constant can be achieved by reducing the number of dipoles and reducing the dipole strength. By reducing the density by introducing pores into the film or adding space volume groups into the molecular structure, the number of dipoles can be effectively reduced, ultimately resulting in low dielectric materials. Introducing voids in the film can take advantage of the low dielectric constant of air, but this method is difficult to precisely control the size and distribution of the pores, resulting in poor dielectric stability of the material. In addition, the dipole strength can be reduced by introducing chemical bonds with lower polarizability (such as C-Si and C-F groups) into the material. This method can accurately control the material and reduce the mediation while maintaining the inherent properties. electrical constant. Therefore, the latter strategy is usually common to technicians, and the obtained low-dielectric materials have a wide range of application scenarios.

Polymer materials have attracted much attention from academia and industry due to their inherent low dielectric constant (ε<3.0), hydrophobic properties, solution processability, and mechanical flexibility. A large number of polymer materials with low dielectric constants have emerged, including poly(imine), poly(aryl ether), poly(ether ketone), poly(p-xylene), fluoropolymers, polysiloxane, Poly-4-methyl-1-pentene, etc., these materials have become mainstream insulation materials. Among them, poly4-methyl-1-pentene has been commercialized. Its dielectric constant (ε<2.3) and density (833kg/m ³ ) are the smallest among synthetic resins. In addition, it has excellent mechanical properties and high transparency. Due to its advantages such as sex and high heat resistance, it is widely used in many high-end fields. However, poly4-methyl-1-pentene has a higher melting point and lower T _g (T _g =25~30°C), which not only limits the processing and formability of the material, but also limits the material’s ability to communicate at high temperatures and high frequencies. Applications in mobile devices.

Contents of the invention

Based on the above content, the present invention provides an ultra-low dielectric copolymer and its preparation method and application. The present invention utilizes a catalyst with copolymerization characteristics of silicon-containing diene (DMSHD) or its derivative monomer and 4-methyl-1-pentene to optimize polymerization conditions and achieve high comprehensive performance (high temperature resistance, high frequency and ultra-low dielectric , high transparency, high modulus and excellent toughness, etc.), and further broaden the application of ultra-low dielectric copolymers in the 5G/6G field (such as insulators for high-frequency connectors, insulators for communication base stations, communication copper-clad laminates, Widely used in semiconductor packaging materials such as electronic packaging trays).

In order to achieve the above objects, the present invention provides the following solutions:

One of the technical solutions of the present invention is an ultra-low dielectric copolymer with a structural formula as shown in Formula I or Formula II:

Among them, R ₁ and R ₂ are independently CH ₃ or Ph; x, a, b, c and d are the mol% of each monomer in the ultra-low dielectric copolymer, and are independently 0 to 100 mol%; a+ b+c+d=1(100mol%);

The weight average molecular weight of the ultra-low dielectric copolymer is 18-80×10 ⁴ g/mol.

Preferably, the ultra-low dielectric copolymer is copolymer 1-6; wherein, the general structural formula of copolymer 1-3 is as shown in Formula I. Specifically, copolymer 1: R ₁ =R ₂ =CH ₃ , Copolymer 2: R ₁ =CH ₃ , R ₂ =Ph, copolymer 3: R ₁ =R ₂ =Ph; the general structural formula of copolymers 4-6 is shown in Formula II. Specifically, copolymer 4: R ₁ =R ₂ =CH ₃ , copolymer 5: R ₁ =CH ₃ , R ₂ =Ph, copolymer 6: R ₁ =R ₂ =Ph.

The second technical solution of the present invention is a preparation method of the above-mentioned ultra-low dielectric copolymer, which includes the following steps:

Mix hydrocarbon solvents, silicon-containing dienes or derivatives thereof, and 4-methyl-1-pentene to obtain a mixed liquid, and then add cocatalysts and single-active center transition metal catalysts to the mixed liquid in sequence to perform polymerization. reaction to obtain the ultra-low dielectric copolymer.

Further, the hydrocarbon compound solvent is at least one of benzene or its homologues, naphthalene or its homologues, alkanes or its homologues, and cycloalkanes or its homologues; the silicon-containing diene or its derivatives It is 3,3-dimethyl-3-silicon-1,5-hexadiene, 3,3-diphenyl-3-silicon-1,5-hexadiene or 3-methyl-3-phenyl -One of 3-silicon-1,5-hexadiene.

Further, the concentration of silicon-containing diene or derivatives thereof in the mixed liquid is 0 to 1 mol/L, preferably 0.3 to 0.9 mol/L; the 4-methyl-1-pentene and the silicon-containing diene are The molar ratio of silicon diene or derivatives thereof is 0 to 100%.

Further, the cocatalyst is methylaluminoxane, dry methylaluminoxane, ethylaluminoxane, ethyl-isobutylaluminoxane, trimethylaluminum, triethylaluminum, triisopropyl or Various, as well as trispentafluorophenylalkborane, trisperfluorobiphenylborane, triphenylmethyltetrakis(pentafluorophenyl)borate, and tert-butyltriphenylmethyltetrakis(pentafluorobenzene) base) borate; preferably, the cocatalyst is a mixture of triisobutylaluminum and triphenylmethyltetrakis(pentafluoro)borate salt.

Further, the structural formula of the single active center transition metal catalyst is as shown in Formula III, Formula IV or Formula V:

Among them, in formula III, R ₁ =2- ⁱ Pr-Ph, ^t Bu or CH ₃ , R ₂ =H or CH ₃ .

Preferably, the single active center transition metal catalyst is one of Cat.1-Cat.5, specifically as follows:

More preferably, the single active center transition metal catalyst is Cat.1.

Further, the molar ratio of the cocatalyst to the single active center transition metal catalyst is (1-2000):1, preferably (50-2000):1, and more preferably (50-300):1. .

Further, the polymerization reaction is specifically: polymerization reaction at 0 to 85°C for 2 to 720 minutes; preferably, the temperature of the polymerization reaction is 25 to 85°C, and more preferably, it is 35°C.

Further, after the polymerization reaction, the step of adding ethanol to terminate the reaction to obtain a reaction liquid, adding the reaction liquid to a precipitant, and then purifying the reaction liquid is included.

The purification treatment specifically includes filtering, washing, dissolving, adsorbing, settling again, filtering again, and vacuum drying in sequence.

The precipitating agent includes at least one of ethanol, methanol, petroleum ether, diethyl ether, n-hexane, acetone, n-pentane, tetrahydrofuran or dichloromethane. Preferably, the precipitating agent is a mixed solution of ethanol and acid with a mass fraction of 0.5-2.5%.

The adsorbent used for adsorption can be one of 100-500 mesh silica gel powder, 100-800 mesh neutral alumina, and 100-200 mesh molecular sieves; preferably, the adsorbent is 200-300 mesh neutral alumina.

The third technical solution of the present invention is the application of the above-mentioned ultra-low dielectric copolymer in the 5G/6G field.

Technical concept of the present invention:

Introducing ring structures containing silicon atoms and aromatic ring structures into the main chain of poly4-methyl-1-pentene is expected to increase its glass transition temperature and optimize its dielectric properties. Based on the above analysis, the present invention designs By introducing 4-methyl-1-pentene monomer into the main chain of poly3,3-dimethyl-3-silyl-1,5-hexadiene (PDMSHD) and its phenyl-containing derivatives, utilizing The unique ring structure and aromatic ring structure formed can significantly increase the glass transition temperature of the copolymer, and the silicon atom content is used to adjust the dielectric properties. By precisely controlling its microstructure and balancing the dielectric constant, heat resistance and comprehensive physical properties and processing properties of the copolymer material, the retained double bonds can be further cross-linked to improve material stability. This new high-performance The copolymer of ultra-low dielectric silicon-containing diene and 1-olefin has the characteristics of ultra-low dielectric and high temperature resistance, and has broad development prospects in the field of high-temperature and high-frequency communications.

The invention discloses the following technical effects:

The present invention uses a single active center transition metal catalyst combined with a cocatalyst to synthesize a series of copolymers of 4-methyl-1-pentene and silicon-containing diene (DMSHD) or its derivatives. According to various catalysts, α-olefins and Silicon-containing dienes have the characteristics of copolymerization ability. The monomer content, T _g , molecular weight and distribution of the copolymer of 4-methyl-1-pentene and DMSHD (or its derivatives) can be realized according to the different monomer ratios. and chain segment microstructure are highly controllable, and high-performance ultra-low dielectric copolymers can be prepared.

The T _g of the copolymer of ultra-low dielectric silicon-containing diene and 4-methyl-1-pentene prepared by the invention is adjustable between 50 and 160°C, and its molecular weight is between 18 and 80×10 ⁴ g/mol adjustable between. By adjusting the addition ratio of DMSHD (or its derivatives), the dielectric constant of the copolymer can be reduced. When the content of DMSHD in the polymer reaches 70%, the dielectric constant can be reduced to 1.97. The copolymer also shows excellent tensile properties, with a tensile strength of more than 30MPa; at the same time, its elongation at break can reach more than 10%; in the visible light range, the light transmittance exceeds 88%. It is worth noting that the present invention uses cheap organic boron salts combined with alkyl metals as cocatalysts, and can efficiently catalyze 4-methyl-1-pentene and DMSHD (or its derivatives) when combined with a single active center transition metal catalyst. Co-polymerization has the potential for commercial value. In addition, the ultra-low dielectric copolymer synthesized in this way can also maintain excellent mechanical properties and heat resistance. The strategy of the present invention to synthesize ultra-low dielectric copolymer has not been reported in many technical fields and is expected to be broadened. This ultra-low dielectric copolymer material is widely used in the 5G/6G mobile field.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some of the drawings of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative efforts.

Figure 1 is a high-temperature GPC curve chart of the copolymers prepared in Examples 2, 3, 5, 7, and 9.

Figure 2 is a DSC curve chart of the copolymers prepared in Examples 2, 3, 5, 8 and 9.

Figure 3 is a stress-strain curve diagram of copolymers prepared in Examples 1, 2, 3, 8, 9, and 11.

Figure 4 is a light transmittance-frequency curve diagram of the copolymers prepared in Examples 1, 3, 5, 7, 8, and 11.

Figure 5 is a dielectric constant curve diagram of the copolymers prepared in Examples 3, 4, and 6-8.

Figure 6 is a dielectric loss curve of the copolymer prepared in Examples 2 and 4-6.

Figure 7 shows ¹ H NMR and ¹³ C NMR of the copolymer prepared in Example 2.

Figure 8 shows ¹ H NMR and ¹³ C NMR of the copolymer prepared in Example 3.

Figure 9 shows ¹ H NMR and ¹³ C NMR of the copolymer prepared in Example 4.

Detailed ways

Various exemplary embodiments of the invention will now be described in detail. This detailed description should not be construed as limitations of the invention, but rather as a more detailed description of certain aspects, features and embodiments of the invention.

It should be understood that the terms used in the present invention are only used to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges in the present invention, it should be understood that every intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or value intermediate within a stated range, and any other stated value or value intermediate within a stated range, is also included within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded from the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only the preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and/or materials in connection with which the documents relate. In the event of conflict with any incorporated document, the contents of this specification shall prevail.

It will be apparent to those skilled in the art that various modifications and changes can be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to the skilled person from the description of the invention. The specification and examples of the present invention are exemplary only.

The words "includes", "includes", "has", "contains", etc. used in this article are all open terms, which mean including but not limited to.

The "room temperature" mentioned in the present invention means 25-35°C unless otherwise specified.

The present invention explores the influence of different types of catalysts and the ratio of different silicon-containing dienes DMSHD or its derivatives to 4-methyl-1-pentene on the electrical properties, mechanical properties and optical properties of the copolymer. In addition, a series of synthesized copolymers were characterized, using high-temperature nuclear magnetic carbon spectroscopy to characterize the microchemical structure of the polymer, high-temperature GPC to test the molecular weight and distribution of the polymer, DSC to study the thermal behavior of the polymer, and tensile testing machine to characterize the polymer's properties. Tensile properties, ultraviolet spectrophotometer to test the light transmittance of the polymer, broadband dielectric spectrometer to test the dielectric properties of the polymer, etc.

The present invention mainly uses a single active center metal catalyst combined with organoboron salts and alkyl metals as cocatalysts to form different catalytic systems, and optimizes the ratio of the main catalyst and cocatalyst, reaction temperature, reaction time and initial molar ratio of monomers to synthesize the A series of low dielectric polymer copolymer materials with excellent properties. First, based on the superior copolymerization ability of single-active center metal catalysts for various α-olefins and silicon-containing dienes, the complexation of different silicon-containing dienes DMSHD or its derivatives with 4-methyl-1-pentene was systematically studied. Compare the effect on polymerization molecular weight to achieve control of copolymer molecular weight. In addition, changing the monomer ratio and different types of catalysts were used to explore the dielectric, mechanical, optical, and thermal effects on the copolymer.

The results of GPC and broadband dielectric spectrometer show that by maintaining a fixed total monomer concentration in the polymerization system using a single active center transition metal catalyst and increasing the proportion of silicon-containing diene or its derivatives, the molecular weight of the copolymer increases, and the dielectric Constant and dielectric losses are reduced. Combining optical and thermal characterization results show that as the proportion of silicon-containing diene or its derivatives increases, the copolymer can not only maintain excellent light transmittance (~90%) in the visible light range, but also increase its _Tg and improve its heat resistance. Also promoted. Tensile property characterization shows that as the proportion of silicon-containing diene or its derivatives increases, the tensile strength and modulus are simultaneously improved, and the copolymer also has satisfactory elongation at break (>10%).

In summary, the present invention can balance the comprehensive properties of the copolymer of 4-methyl-1-pentene and silicon-containing diene DMSHD or its derivatives, and the obtained high-performance ultra-low dielectric material is expected to be implemented in the 5G/6G mobile field. widely used.

The single active center transition metal catalysts Cat.1, 2 and 3 of the present invention are pyridine imine hafnium catalysts, which are synthesized according to the literature Angewandte Chemie 2006, 45(20), 3278-3283. Other single active center transition metal catalysts are purchased from Anaiji Chemical Company of China.

In the process of synthesizing the catalyst, the operations involved, unless otherwise specified, are performed by professionals familiar with the technical field in an MBraun glove box or using standard Schlenk technology under the protection of inert gases such as nitrogen or argon.

The solvents involved in the present invention are all water-free and oxygen-free solvents after post-treatment.

During the preparation of ultralow dielectric copolymers of silicon-containing dienes and 1-olefins, all moisture- and oxygen-sensitive operations were performed by professionals familiar with the art in an MBraun glove box or under nitrogen protection using standard Schlenk techniques. proceed below.

The test methods involved in the present invention are as follows:

Nuclear magnetic resonance spectroscopy (NMR) was used to characterize the chemical structure of the copolymer.

Differential scanning calorimetry (DSC) was used to characterize the thermal properties of the copolymers.

High-temperature gel chromatography (GPC) was used to characterize the molecular weight and molecular weight distribution of the copolymer. ^{The 1} H and ¹³ CNMR of the copolymer were measured by a Bruker-400 nuclear magnetic resonance instrument at 120°C. TMS was used as the internal standard, and the solvent was deuterated ortho-2. Chlorobenzene or deuterated 1,1,2,2-tetrachloroethane.

The glass transition temperature (T _g ) of the copolymer was measured by a differential thermal scanning calorimeter (Q2000 DSC). The test conditions were: under nitrogen atmosphere, the temperature rise/fall rate was 20°C/min.

Gel chromatography was measured using (GPC)PL GPC-220 gel permeation chromatography. The tester was RI-Laser, PLEasiCal PS-1 was used as the standard sample, and the packed column was Plgel 10μm MIXED-BLS, 1,2,4- Trichlorobenzene (TCB) was used as the solvent, and 0.05wt% 2,6-di-tert-butyl-4-methylphenol (BHT) was added as an antioxidant. The test temperature was 150°C, and the flow rate was 1.0mL/min.

A universal testing machine (Instron 3360) was used to perform a tensile test on the sample at a temperature of 25°C (tensile spline length 10mm, width 5mm, thickness 0.5mm; based on ISO 527-1 as the standard, the tensile rate is 10mm/ min).

Use a Lambda750 UV spectrophotometer to test the light transmittance (T.) of the copolymer film in the wavelength range of 350 to 800 nm. The test method is to clamp the copolymer film onto a quartz plate with a diameter of 2cm.

A broadband dielectric spectrometer (Novelcontrol, Germany) was used to test the dielectric properties of the copolymer at 100-10M Hz.

The structural formula of the single active center transition metal catalyst used in the embodiments of the present invention is as follows:

The concentration of triisobutylaluminum in the toluene solution of triisobutylaluminum used in the embodiments of the present invention is 1.0 mol/L.

Example 1

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 9 equiv of 4-methyl-1-pentene (concentration: 0.54 mol/L) to the polymerization bottle under nitrogen conditions; then, add 1 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.06mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, settling again, filtering again, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer (i.e., Ultra-low dielectric copolymer of silicon-containing diene and 1-olefin (referred to as copolymer), pending subsequent characterization.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The content of silicon-containing diene in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 22.2 mol%, and the copolymer is vitrified. The transition temperature (T _g ) was 60.4°C, the polymerization showed amorphous behavior, and the monomer conversion rate was 53.5%. Within 100-10M Hz, the dielectric constant of the copolymer is as low as 2.20. High-temperature GPC result analysis shows that the weight average molecular weight is 18.2×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.79). In addition, tensile property characterization results show that the tensile strength (δ) of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 34.0MPa , the tensile modulus is 2602.5MPa, and the tensile elongation at break (&) is 16.8%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is more than 89.4%. Specific copolymer data are shown in Table 1.

Example 2

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 8 equiv of 4-methyl-1-pentene (concentration: 0.48 mol/L) to the polymerization bottle under nitrogen conditions; then, add 2 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.12mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, settling again, filtering again, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer (i.e., Ultra-low dielectric copolymer of silicon-containing diene and 1-olefin (referred to as copolymer), pending subsequent characterization.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer obtained in this example was subjected to nuclear magnetic and DSC tests. The test results showed that this example The silicon-containing diene insertion rate in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 39.1 mol%, and its copolymer glass The chemical transition temperature (T _g ) is 66.5°C, the polymerization shows amorphous behavior, and the monomer conversion rate is 60.4%. Within 100-10M Hz, the dielectric constant of the copolymer is as low as 2.19. High-temperature GPC result analysis shows that the weight average molecular weight is 23.9×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.72). In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 37.7MPa. The modulus is 2266.5MPa, and the tensile elongation at break is 15.3%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is more than 90.4%. Specific copolymer data are shown in Table 1.

The ¹ H and ¹³ CNMR data of the 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example are shown in Figure 7.

Example 3

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 7 equiv of 4-methyl-1-pentene (concentration: 0.42 mol/L) to the polymerization bottle under nitrogen conditions; then, add 3 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.18mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, settling again, filtering again, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer (i.e., Ultra-low dielectric copolymer of silicon-containing diene and 1-olefin (referred to as copolymer), pending subsequent characterization.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The silicon-containing diene in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 60.4 mol%, and the glass transition of the copolymer is The temperature (T _g ) was 72.2°C, the polymerization showed amorphous behavior, and the monomer conversion rate was 66.6%. Within 100~10M Hz, the dielectric constant of the copolymer is as low as 2.18. High-temperature GPC result analysis shows that the weight average molecular weight is 30.9×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.60). In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 46.7MPa. The modulus is 2346.3MPa, and the tensile elongation at break is 12.1%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is more than 90.4%. Specific copolymer data are shown in Table 1.

The ¹ H and ¹³ CNMR data of the 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example are shown in Figure 8.

Example 4

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 6 equiv of 4-methyl-1-pentene (concentration of 0.36 mol/L) to the polymerization bottle under nitrogen conditions; then, add 4 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.24mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washed, and vacuum dried to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer (i.e., ultra-low dielectric silicon-containing diene and 1 -Olefin copolymer, referred to as copolymer), to be characterized later.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The content of silicon-containing diene in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 70.8 mol%, and the copolymer is vitrified. The transition temperature (T _g ) was 85.5°C, the polymerization showed amorphous behavior, and the monomer conversion rate was 70.9%. Within 100-10M Hz, the dielectric constant of the copolymer is as low as 2.14. High-temperature GPC result analysis shows that the weight average molecular weight is 44.7×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.73). In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 51.3MPa. The modulus is 2313.9MPa, and the tensile elongation at break is 9.5%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is more than 89.7%. Specific copolymer data are shown in Table 1.

The ¹ H and ¹³ CNMR data of the 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example are shown in Figure 9.

Example 5

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 5 equiv of 4-methyl-1-pentene (concentration of 0.30 mol/L) to the polymerization bottle under nitrogen conditions; then, add 5 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.30mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washed, and vacuum dried to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer (i.e., ultra-low dielectric silicon-containing diene and 1 -Olefin copolymer, referred to as copolymer), to be characterized later.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The content of silicon-containing diene in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 79.6 mol%, and the copolymer is vitrified. The transition temperature (T _g ) was 90.1°C, the polymerization showed amorphous behavior, and the monomer conversion rate was 77.8%. Within 100-10M Hz, the dielectric constant of the copolymer is as low as 2.10. High-temperature GPC result analysis shows that the weight average molecular weight is 62.9×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.56). In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 56.4MPa. The modulus is 2333.0MPa, and the tensile elongation at break is 6.7%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is more than 90.4%. Specific copolymer data are shown in Table 1.

Example 6

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using a Schlenk experimental device and under nitrogen conditions, add 4 equiv of 4-methyl-1-pentene (concentration: 0.24 mol/L) into the polymerization bottle; then, add 6 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.36mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, settling again, filtering again, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer (i.e., Ultra-low dielectric copolymer of silicon-containing diene and 1-olefin (referred to as copolymer), pending subsequent characterization.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The silicon-containing diene insertion rate in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 84.7 mol%, and its copolymer glass The chemical transition temperature (T _g ) is 92.3°C, the polymerization shows amorphous behavior, and the monomer conversion rate is 87.3%. Within 100~10M Hz, the dielectric constant of the copolymer is as low as 2.09. Analysis of high-temperature GPC results showed that the weight average molecular weight was 64.2×10 ⁴ g/mol and the molecular weight distribution was narrow (PDI=1.76). In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 60.3MPa. The modulus is 2523.8MPa, and the tensile elongation at break is 5.4%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is more than 90.1%. Specific copolymer data are shown in Table 1.

Example 7

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and under nitrogen conditions, add 3 equiv of 4-methyl-1-pentene (concentration: 0.18 mol/L) into the polymerization bottle; then, add 7 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.42mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, settling again, filtering again, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer (i.e., Ultra-low dielectric copolymer of silicon-containing diene and 1-olefin (referred to as copolymer), pending subsequent characterization.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The content of silicon-containing diene in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 90.2 mol%, and its copolymer glass The chemical transition temperature (T _g ) is 95.7°C, the polymerization shows amorphous behavior, and the monomer conversion rate is 90.6%. Within 100~10M Hz, the dielectric constant of the copolymer is as low as 1.97. High-temperature GPC result analysis shows that the weight average molecular weight is 69.3×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.49). In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 62.1MPa. The modulus is 2534.3MPa, and the tensile elongation at break is 5.0%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is more than 90.3%. Specific copolymer data are shown in Table 1.

Example 8

A method for preparing an ultra-low dielectric homopolymer of 4-methyl-1-pentene, using a single active center transition metal Cat.1 as a catalyst for olefin coordination copolymerization. All polymerization reactions require anhydrous conditions. It is carried out under anaerobic conditions. The polymerization bottles, syringes, ampoules and other glassware involved in the reaction, such as weighing and transferring catalysts, co-catalysts, solutions, etc., have all undergone anhydrous and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 4-methyl-1-pentene (concentration: 0.60 mol/L) to the polymerization bottle under nitrogen conditions; after stabilization, the chain transfer agent triisotope is added in sequence. Butylaluminum toluene solution (10mmol), 0.25mmol/L catalyst (Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C][B(C ₆ F ₅ ) ₄ ], maintain the total capacity of the polymerization bottle at 40 mL with toluene solvent, and stir the reaction at room temperature for 240 min at 400 rpm; then add 0.5 mL of ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a solution containing 300 mL of ethanol/ Hydrochloric acid (volume ratio 50:1) was settled in a beaker, and then filtered, washed, dissolved, adsorbed, sedimented again, filtered again, and vacuum dried to obtain 4-methyl-1-pentene homopolymer, which will be characterized later.

The 4-methyl-1-pentene homopolymer prepared in this example was subjected to nuclear magnetic and DSC tests. The test results showed that the melting temperature (T _m ) is 236.7°C, and the monomer conversion rate is 43.9%. The polymer is insoluble in trichlorobenzene under heating and shaking conditions at 150°C. In addition, the tensile property characterization results show that the tensile strength of 4-methyl-1-pentene homopolymer is 32.0MPa, the tensile modulus is 2419.7MPa, and the tensile elongation at break is 64.5%. Within 100 to 10MHz, the dielectric constant of the homopolymer is as low as 2.21. UV spectrophotometer test results show that in the range of visible light, the homopolymer has a light transmittance of more than 90.1%. Specific homopolymer data are shown in Table 1.

Example 9

A method for preparing an ultra-low dielectric homopolymer of silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene, using single active center transition metal Cat.1 as a catalyst For olefin coordination copolymerization, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules and other glassware involved in the reaction, such as weighing and transferring catalysts, co-catalysts, solutions, etc., must be anhydrous and oxygen-free. Oxygen treatment. The specific reaction steps are: using Schlenk experimental device and adding 3,3-dimethyl-3-silyl-1,5-hexadiene (concentration: 0.60 mol/L) to the polymerization bottle under nitrogen flow conditions; After stabilization, chain transfer agent triisobutylaluminum toluene solution (10mmol), 0.25mmol/L catalyst (Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], maintain the total capacity of the polymerization bottle at 40 mL with toluene solvent, stir the reaction at room temperature at 400 rpm for 240 min; then add 0.5 mL of ethanol to terminate the polymerization, and obtain a reaction solution; The reaction solution was poured dropwise into a beaker containing 300 mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filtered, washed, dissolved, adsorbed, sedimented again, filtered again, and vacuum dried to obtain 3,3-dimethyl-3 -Silicon-1,5-hexadiene homopolymer, pending subsequent characterization.

The 3,3-dimethyl-3-silicon-1,5-hexadiene homopolymer prepared in this example was subjected to nuclear magnetic and DSC tests. The test results showed that the 3,3-dimethyl The glass transition temperature (T _g ) of the base-3-silicon-1,5-hexadiene homopolymer is 99.1°C, the melting temperature (T _m ) is 227.7°C, and the monomer conversion rate is 91.9%. In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene homopolymer is 56.5MPa, the tensile modulus is 2605.7MPa, and the tensile fracture Elongation 4.0%. Within 100~10M Hz, the dielectric constant of the homopolymer is as low as 1.85. High-temperature GPC result analysis shows that the weight average molecular weight is 102.6×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.95). UV spectrophotometer test results show that in the range of visible light, the homopolymer has a light transmittance of more than 90.2%. Specific homopolymer data are shown in Table 1.

Example 10

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.2 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 7 equiv of 4-methyl-1-pentene (concentration: 0.42 mol/L) to the polymerization bottle under nitrogen conditions; then, add 3 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.18mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, re-sedimentation, re-filtering, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer, which will be processed later. representation.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The content of silicon-containing diene in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 48.7 mol%, and the copolymer is vitrified. The transition temperature (T _g ) was 70.1°C, the polymerization showed amorphous behavior, and the monomer conversion rate was 37.4%. Within 100~10M Hz, the dielectric constant of the copolymer is the lowest 2.82. High-temperature GPC result analysis shows that the weight average molecular weight is 21.8×10 ⁴ g/mol, and the molecular weight distribution width PDI=2.92. In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 36.8MPa. The modulus is 2216.4MPa, and the tensile elongation at break is 14.1%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is 88.4%. Specific copolymer data are shown in Table 1.

Example 11

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using single active center transition metal Cat.3 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 7 equiv of 4-methyl-1-pentene (concentration: 0.42 mol/L) to the polymerization bottle under nitrogen conditions; then, add 3 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.18mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction solution; pour the reacted solution dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then After filtration, washing, dissolving, adsorption, re-sedimentation, re-filtration and vacuum drying, 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is obtained. Awaiting subsequent characterization. .

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The content of silicon-containing diene in the polymerized 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 43.6 mol%, and its copolymer glass The chemical transition temperature (T _g ) is 68.8°C, the polymer exhibits amorphous behavior, and the polymerization conversion rate is 29.8%. Within 100~10M Hz, the lowest dielectric constant of homopolymer is 2.49. High-temperature GPC result analysis shows that the weight average molecular weight is 19.2×10 ⁴ g/mol, and the molecular weight distribution is broad (PDI=3.06). In addition, the tensile property characterization results show that the tensile strength of 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer is 43.7MPa. The modulus is 2456.3MPa, and the tensile elongation at break is 10.2%. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is 86.4%. Specific copolymer data are shown in Table 1.

Example 12

A preparation method of ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using Cat.4rac-Et(Ind) ₂ ZrCl ₂ is a catalyst for olefin coordination copolymerization. All polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction are weighed and transferred to glass such as catalysts, cocatalysts, solutions, etc. The utensils are treated without water or oxygen. The specific reaction steps are: using the Schlenk experimental device and adding 7 equiv of 4-methyl-1-pentene (concentration: 0.18 mol/L) to the polymerization bottle under nitrogen conditions; then, add 3 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.42mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, re-sedimentation, re-filtering, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer, which will be processed later. representation.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer obtained by polymerization contains 31.8 mol% of silicon diene, and the glass transition temperature of the copolymer is (T _g ) was 66.4°C, the polymerization showed amorphous behavior, and the monomer conversion rate was 5.6%. Within 100~10M Hz, the dielectric constant of the copolymer is the lowest 2.76. High-temperature GPC result analysis shows that the weight average molecular weight is 10.3×10 ⁴ g/mol, and the molecular weight distribution is broad (PDI=5.64). The UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is 84.3%. Specific copolymer data are shown in Table 1.

Example 13

A preparation method of ultra-low dielectric copolymer based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD), using Cat.5rac-Et(Ind) ₂ ZrCl ₂ is a catalyst for olefin coordination copolymerization. All polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction are weighed and transferred to glass such as catalysts, cocatalysts, solutions, etc. The utensils are treated without water or oxygen. The specific reaction steps are: using the Schlenk experimental device and adding 7 equiv of 4-methyl-1-pentene (concentration: 0.18 mol/L) to the polymerization bottle under nitrogen conditions; then, add 3 equiv of 3,3 -Dimethyl-3-silyl-1,5-hexadiene (concentration: 0.42mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, re-sedimentation, re-filtering, and vacuum drying to obtain 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer, which will be processed later. representation.

The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The 3,3-dimethyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer obtained by polymerization contains 37.9 mol% of silicon diene, and the glass transition temperature of the copolymer is (T _g ) was 68.7°C, the polymerization showed amorphous behavior, and the monomer conversion rate was 48.2%. Within 100~10M Hz, the dielectric constant of the copolymer is the lowest 2.27. Analysis of high-temperature GPC results showed that the weight average molecular weight was 12.2×10 ⁴ g/mol and the molecular weight distribution was broad (PDI=2.41). UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is 88.7%. Specific copolymer data are shown in Table 1.

Example 14

A method for preparing an ultra-low dielectric copolymer based on silicon-containing diene 3,3-diphenyl-3-silicon-1,5-hexadiene (DPSHD), using single active center transition metal Cat.1 as For olefin coordination copolymerization carried out by catalyst, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions. The polymerization bottles, syringes, ampoules, etc. involved in the reaction and the glassware for weighing and transferring catalysts, cocatalysts, solutions, etc. Water-free and oxygen-free treatment. The specific reaction steps are: using the Schlenk experimental device and adding 7 equiv of 4-methyl-1-pentene (concentration: 0.42 mol/L) to the polymerization bottle under nitrogen conditions; then, add 3 equiv of 3,3 -Diphenyl-3-silicon-1,5-hexadiene (concentration: 0.18mol/L); after stabilization, add chain transfer agent triisobutylaluminum toluene solution (10mmol) and 0.25mmol/L catalyst ( Cat.1) and 0.5mmol/L triphenylmethyltetrakis(pentafluoro)borate salt [Ph ₃ C] [B(C ₆ F ₅ ) ₄ ], and use toluene solvent to maintain the total capacity of the polymerization bottle at 40mL, stir the reaction at room temperature for 240min at 400rpm; then add 0.5mL ethanol to terminate the polymerization to obtain a reaction liquid; pour the reaction liquid dropwise into a beaker containing 300mL ethanol/hydrochloric acid (volume ratio 50:1) to settle, and then filter , washing, dissolving, adsorbing, re-sedimentation, re-filtering, and vacuum drying to obtain 3,3-diphenyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer, which will be processed later. representation.

The 3,3-diphenyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer prepared in this example was subjected to NMR and DSC tests. The test results showed that this example The 3,3-diphenyl-3-silicon-1,5-hexadiene/4-methyl-1-pentene copolymer obtained by polymerization contains 52.7 mol% of silicon diene and the monomer conversion rate is 53.3%. , T _g =121.2℃. High-temperature GPC result analysis shows that the weight average molecular weight is 32.3×10 ⁴ g/mol, and the molecular weight distribution is narrow (PDI=1.71). Within 100~10M Hz, the lowest dielectric constant of homopolymer is 1.96. UV spectrophotometer test results show that in the range of visible light, the light transmittance of the copolymer is 90.4%. Specific copolymer data are shown in Table 1.

Table 14 - Performance data of methyl-1 ^- pentene and silicon-containing diene copolymera

^a Reaction conditions; ^b High-temperature GPC test; ^c Silicon-containing diene or its derivative insertion rate (content), calculated by ¹³ C NMR; ^d DSC test; ^e Tensile machine test, δ = tensile strength, &= Elongation at break; ^f Characterized by ultraviolet spectrophotometer, T = transmittance (800nm); ^g Tested by broadband dielectric spectrometer.

Figure 1 is a high-temperature GPC curve chart of the copolymers prepared in Examples 2, 3, 5, 7, and 9.

Figure 2 is a DSC curve chart of the copolymers prepared in Examples 2, 3, 5, 8 and 9.

Figure 3 is a stress-strain curve diagram of the copolymers prepared in Examples 1, 2, 3, 8, 9, and 11.

Figure 4 is a light transmittance-frequency curve diagram of the copolymers prepared in Examples 1, 3, 5, 7, 8, and 11.

Figure 5 is a dielectric constant curve diagram of the copolymers prepared in Examples 3, 4, and 6-8.

Figure 6 is a dielectric loss curve of the copolymer prepared in Examples 2 and 4-6.

It can be seen from the above figures and the data in Table 1 that compared with Example 3, the molecular weight of the copolymers in Examples 10-13 is lower and the molecular weight distribution is wider. The mechanical properties and optical properties of the obtained copolymers are poor, and the dielectric properties are poor. is also poor, thus highlighting that the copolymer obtained by Cat.1 catalyzed copolymerization of 4-methyl-1-pentene and 3,3-dimethyl-3-silyl-1,5-hexadiene or its derivatives has better Good performance advantages.

The present invention discloses and proposes a method for preparing ultra-low dielectric copolymer materials based on silicon-containing diene 3,3-dimethyl-3-silicon-1,5-hexadiene (DMSHD) and its derivatives. The content of the silicon-containing diene DMSHD or its derivatives in the high-performance ultra-low dielectric copolymer prepared by the method of the present invention is 0 to 100%; T _g =25 to 121°C; the weight average molecular weight of the copolymer is 18 to 80×10 ⁴ g/mol, the molecular weight distribution is between 1.5 and 5.6; the conversion rate of the monomer is between 5 and 92%; the dielectric constant of the copolymer is 1.9~2.4, and the dielectric loss is 0.00001~0.001; copolymerization The tensile strength of the material is 30~70MPa, the tensile modulus is >2000MPa, the elongation at break is 10~90%; the transparency of the copolymer is >88%. The present invention broadens the application scope of polycarbosilane and systematically reveals the relationship between the content of silicon-containing diene 3,3-dimethyl-3-silyl-1,5-hexadiene (DMSHD) or its derivatives and the dielectric The influence rules between performances are of very important research significance.

The above-described embodiments only describe the preferred modes of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, those of ordinary skill in the art can make various modifications to the technical solutions of the present invention. All deformations and improvements shall fall within the protection scope determined by the claims of the present invention.

Claims (10)

1. An ultra-low dielectric copolymer, characterized in that the structural formula is as shown in Formula I or Formula II: Among them, R ₁ and R ₂ are independently CH ₃ or Ph; x, a, b, c and d are the mol% of each monomer in the ultra-low dielectric copolymer, and are independently 0 to 100 mol%; The weight average molecular weight of the ultra-low dielectric copolymer is 18-80×10 ⁴ g/mol. 2. A preparation method of ultra-low dielectric copolymer according to claim 1, characterized in that it includes the following steps: Mix hydrocarbon solvents, silicon-containing dienes or derivatives thereof, and 4-methyl-1-pentene to obtain a mixed liquid, and then add cocatalysts and single-active center transition metal catalysts to the mixed liquid in sequence to perform polymerization. reaction to obtain the ultra-low dielectric copolymer. 3. The preparation method of ultra-low dielectric copolymer according to claim 2, characterized in that the hydrocarbon compound solvent is benzene or its homologues, naphthalene or its homologues, alkanes or its homologues and cycloalkanes Or at least one of its homologues; the silicon-containing diene or its derivative is 3,3-dimethyl-3-silicon-1,5-hexadiene, 3,3-diphenyl-3 - One of silicon-1,5-hexadiene or 3-methyl-3-phenyl-3-silyl-1,5-hexadiene. 4. The preparation method of ultra-low dielectric copolymer according to claim 2, characterized in that the concentration of silicon-containing diene or derivatives thereof in the mixed liquid is 0 to 1 mol/L; the 4-methane The molar ratio of 1-pentene to the silicon-containing diene or its derivative is 0 to 100%. 5. The preparation method of ultra-low dielectric copolymer according to claim 2, characterized in that the cocatalyst is methylaluminoxane, dry methylaluminoxane, ethylaluminoxane, ethyl- Isobutylaluminoxane, trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, ethylaluminum dichloride, diethylaluminum chloride, diethylzinc, diethyl aluminum One or more of magnesium base, diisobutyl magnesium or n-butylethyl magnesium, as well as tripentafluorophenylalkborane, triperfluorobiphenylborane, triphenylmethyltetrakis(pentafluoro One or more of phenyl)borate and tert-butyltriphenylmethyltetrakis(pentafluorophenyl)borate. 6. The preparation method of ultra-low dielectric copolymer according to claim 2, characterized in that the structural formula of the single active center transition metal catalyst is as shown in formula III, formula IV or formula V: Among them, in formula III, R ₁ =2- ⁱ Pr-Ph, ^t Bu or CH ₃ , R ₂ =H or CH ₃ . 7. The method for preparing an ultra-low dielectric copolymer according to claim 2, wherein the molar ratio of the cocatalyst to the single active center transition metal catalyst is (1-2000):1. 8. The preparation method of ultra-low dielectric copolymer according to claim 2, characterized in that the polymerization reaction is specifically: polymerization reaction at 0-85°C for 2-720 minutes. 9. The preparation method of ultra-low dielectric copolymer according to claim 2, characterized in that, after the polymerization reaction, it also includes adding ethanol to terminate the reaction to obtain a reaction liquid, adding the reaction liquid to a precipitant, and then purifying Processing steps. 10. Application of the ultra-low dielectric copolymer as claimed in claim 1 in the 5G/6G field.