Fluorine-free silicon-containing copolymer with high heat resistance and ultralow dielectric and preparation method thereof

Abstract

The invention discloses a fluorine-free silicon-containing copolymer with high heat resistance and ultralow dielectric and a preparation method of the fluorine-free silicon-containing copolymer, and belongs to the technical field of preparation of high-performance ultralow dielectric materials. The preparation method of the high-heat-resistance and ultralow-dielectric fluorine-free silicon-containing copolymer comprises the following steps: mixing large-steric-hindrance aryl-substituted symmetric silicon-containing diene, alpha-olefin, a catalyst, a co-catalyst and a hydrocarbon compound solvent to obtain a mixture, and then heating for polymerization reaction to obtain the high-heat-resistance and ultralow-dielectric fluorine-free silicon-containing copolymer. The dielectric constant and the dielectric loss of the high-heat-resistance and ultralow-dielectric fluorine-free silicon-containing copolymer prepared after condition optimization can respectively reach: epsilon = 1.30-1.50, tan delta is less than or equal to 3.13 * 10 <-4 >, meanwhile, the copolymer also shows high heat resistance, the glass transition temperature Tg of the material is 110.0-170.2 DEG C, and the high decomposition temperature Td95 is greater than or equal to 414.2 DEG C.

Description

Technical Field

[0001] The present invention relates to the technical field of high-performance ultra-low dielectric material preparation, and in particular to a high-heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer and a preparation method thereof. Background Art

[0002] With the advent of the era of artificial intelligence, the Internet of Things, and 5G communications, integrated circuits are smaller in size and more integrated. The parasitic effects of capacitance and resistance (RC) caused by "high speed" and "high frequency" are also aggravated, resulting in signal transmission delays and distortions, and even affecting the safety and stability of equipment use. In order to reduce the impact of parasitic effects, the development of low dielectric constant interlayer insulating materials has attracted widespread attention. Generally, inorganic materials are widely used as interlayer dielectric materials in the field of microelectronics due to their excellent high temperature resistance and low dielectric constant, such as silicon oxide and silicon nitride, but their poor processability limits their application in the field of intelligent materials such as soft robots and artificial muscles. Polymer-based insulating materials have good hydrophobicity, processability, low dielectric constant, and low cost, and have attracted widespread attention in the industry. In recent years, dielectric polymer materials used in the field of electronic information mainly include polyimide (PI), low-density polyethylene (LDPE), poly-4-methyl-1-pentene (PMP), polysiloxane, fluorinated polymers, etc. Polyimide is favored by researchers because of its excellent thermal stability and chemical stability, but the dielectric constant (ε) of this material is usually between 3.0 and 3.6, which cannot meet the use requirements of insulating materials under high frequency and high speed; low-density polyethylene has good chemical stability, low conductivity, small dielectric constant, and low dielectric loss tangent, but its heat resistance is extremely poor, which limits its application in high-temperature and high-frequency materials; poly-4-methyl-1-pentene is one of the materials with the lowest dielectric constant among synthetic resins (ε≈2.4), but it is expensive and the synthesis cost is too high. Therefore, designing a low-cost polymer material with good high temperature resistance and ultra-low dielectric constant has become the focus of researchers in the development of dielectric polymer materials.

[0003] The main design ideas for low dielectric constant materials include reducing the number of dipoles and reducing the dipole strength. The commonly used principle in design is to introduce groups with low polarizability such as fluorine-containing groups. However, the synthetic route for introducing fluorine-containing groups is relatively complicated. In addition, the use of fluorine-containing materials may produce corrosive substances such as hydrofluoric acid, which will pose a potential threat to production equipment and the environment. The handling and discharge of corrosive substances also increase production costs and environmental burdens. Therefore, it is very necessary to develop a high-heat-resistant, ultra-low dielectric, fluorine-free, low-cost polymer material. Summary of the invention

[0004] The purpose of the present invention is to provide a highly heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer and a preparation method thereof, so as to solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention is a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer, the structural formula of which is

[0007] Wherein, R=H, CH3 or (CH2) n CH3, n is an integer from 1 to 10, R3 and R4 are selected from one of the following two situations:

[0008] Option 1: R3 = R4 = phenyl, indenyl, fluorenyl, naphthyl or anthracenyl;

[0009] Option 2: R3 = CH3, R4 = phenyl, indenyl, fluorenyl, naphthyl or anthracenyl.

[0010] In order to further reduce the dielectric constant and dielectric loss of the polymer, improve the heat resistance and glass transition temperature of the material, and significantly reduce the synthesis cost of the material, the present invention uses cheap and easily available α-olefins such as ethylene, propylene, butene, etc. as polymerization monomers to replace expensive 4-methyl-1-pentene to construct an olefin main chain structure, and copolymerizes with symmetrical dienes containing carbon-silicon covalent bonds containing aromatic structures such as benzene rings, indene, and fluorenyl with large steric hindrance. The introduction of C-Si bonds in the polymer can reduce the dipole strength, and the introduction of large steric hindrance aromatic structure substituents can improve the high temperature resistance of the material. Symmetrical silicon-containing dienes substituted with large steric hindrance aromatic groups are used as the main body, copolymerized with cheap and easily available α-olefins and controlling the ring formation ratio of dienes, broadening the copolymerization options of symmetrical silicon-containing dienes. This type of new low-dielectric polymer material not only obtains unprecedented ultra-low dielectric constants (ε=1.30~1.50) and dielectric losses (tanδ≤3.13×10 -4 ) performance, and the α-olefin copolymer unit further optimizes the mechanical properties of the copolymer and has a lower cost. At the same time, the symmetrical structure and the large aromatic steric hindrance effect synergistically improve the glass transition temperature of the copolymer, making up for the poor temperature resistance of polymer-based insulating materials. This type of new material has broad practical application prospects in the field of high-frequency and high-temperature communications.

[0011] Furthermore, the weight average molecular weight of the high heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer is (35-150)×10 4 g / mol.

[0012] Furthermore, the content of the symmetrical silicon-containing diene substituted with a large steric hindrance aromatic group in the high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer is 10 to 100 mol %, and is not 100 mol %.

[0013] Technical solution 2 of the present invention: The preparation method of the above-mentioned high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer comprises the following steps:

[0014] A symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group, an α-olefin, a catalyst, a co-catalyst, a chain transfer agent and a hydrocarbon compound solvent are mixed to obtain a mixture, and then heated to carry out a polymerization reaction to obtain the highly heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer;

[0015] The symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group includes one of diallyldiphenylsilane (DDPS), diallylmethylphenylsilane (DMPS), diallyldiindenylsilane, diallylmethylindenylsilane (DMIS), diallyldifluorenylsilane, diallylmethylfluorenylsilane (DMFS), diallyldinaphthylsilane, diallylmethylnaphthylsilane, diallyldianthracenylsilane and diallylmethylanthracenylsilane;

[0016] The α-olefin includes one of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene and 1-dodecene;

[0017] Furthermore, the hydrocarbon compound solvent includes one or more of benzene and its homologues, indene and its homologues, naphthalene and its homologues, alkanes and its homologues, and cycloalkanes and its homologues.

[0018] Further, the catalyst is a single active site transition metal catalyst;

[0019] And / or, the co-catalyst includes one or more of tripentafluorophenyl borane, triperfluorobiphenyl borane, triphenylmethyl tetrakis(pentafluorophenyl)borate ([Ph3C][B(C6F5)4]) and tert-butyltriphenylmethyl tetrakis(pentafluorophenyl)borate.

[0020] And / or, the chain transfer agent includes one or more of methylaluminoxane (MAO), modified methylaluminoxane (MMAO), ethylaluminoxane, isobutylaluminoxane, trimethylaluminum, diethylaluminum chloride, triethylaluminum, triisopropylaluminum, triisobutylaluminum, diethylzinc, diethylmagnesium, dibutylmagnesium and n-butylethylmagnesium.

[0021] Furthermore, the co-catalyst is preferably triphenylmethyltetrakis(pentafluorophenyl)borate.

[0022] Furthermore, the chain transfer agent is preferably triisobutylaluminum.

[0023] Furthermore, the concentration of the symmetrical silicon-containing diene substituted with a bulky sterically hindered aromatic group in the mixture is 0.1 to 0.2 mol / L, preferably 0.2 mol / L;

[0024] and / or, the concentration of the α-olefin in the mixture is 0.02 to 0.2 mol / L;

[0025] And / or, the concentration of the catalyst in the mixture is (1.5-2)×10 -4 mol / L, preferably 1.7×10 -4 mol / L;

[0026] And / or, the molar ratio of the catalyst to the co-catalyst is 1:1 to 2000, preferably 1:2.

[0027] And / or, the molar ratio of the catalyst to the chain transfer agent is 1:10 to 1000, preferably 1:150.

[0028] Furthermore, the polymerization reaction temperature is 20-85° C., and the time is 10-720 min.

[0029] Furthermore, after the polymerization reaction is completed, ethanol is added to terminate the polymerization reaction to obtain a reaction solution, the reaction solution is mixed with an acidified precipitant, and the steps of primary sedimentation, primary washing, primary filtration, dissolution, adsorption, secondary sedimentation, secondary filtration, secondary washing, and vacuum drying are performed.

[0030] Further, the precipitant includes one or more of ethanol, methanol, petroleum ether, ether, n-hexane, acetone, n-pentane, tetrahydrofuran and dichloromethane, preferably ethanol;

[0031] And / or, the acidification includes: mixing an acid with a precipitant, that is, the precipitant after acidification is a mixed solution of the precipitant and the acid.

[0032] Furthermore, the acid is hydrochloric acid, and the volume ratio of the precipitant to the hydrochloric acid is 50:1.

[0033] Furthermore, the concentration of the hydrochloric acid is 38wt%.

[0034] Furthermore, the single active site transition metal catalyst is Me2Si(Ind)2ZrCl2 (structural formula: Abbreviated as Cat.4) or the structural formula is A compound, wherein R1 and R2 are selected from one of the following three situations:

[0035] Option 1: R1 = H, R2 = 2- iPr-Ph (compound referred to as Cat. 1);

[0036] Option 2: R1 = R2 = CH3 (the compound is referred to as Cat. 2);

[0037] Option 3: R1= t Bu, R2=CH3 (the compound is abbreviated as Cat. 3).

[0038] Furthermore, the single active site transition metal catalyst is preferably Cat.1.

[0039] Furthermore, the adsorption includes: adsorption using an adsorbent; the adsorbent includes one of 100-500 mesh silica gel powder, 100-800 mesh neutral alumina, and 100-200 mesh molecular sieve, preferably 200-300 mesh neutral alumina.

[0040] Further preferably, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallylmethylphenylsilane (DMPS), and the structural formula of the highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer is as shown in Formula I;

[0041] Or, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallylmethylindenylsilane (DMIS), and the structural formula of the highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer is as shown in Formula II;

[0042] Or, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallyldiphenylsilane (DDPS), and the structural formula of the highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer is as shown in Formula III;

[0043] Or, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallylmethylfluorenylsilane (DMFS), and the structural formula of the highly heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer is as shown in Formula IV;

[0044]

[0045] Wherein, R=H, CH3 or (CH2) n CH3, n is an integer from 1 to 10. Preferably, R=H, CH3, CH2CH3, (CH2)2CH3 or (CH2)3CH3.

[0046] The third technical solution of the present invention: Application of the above-mentioned high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer in the preparation of high-performance microwave substrates, millimeter wave substrates or packaging materials.

[0047] The present invention mainly uses a variety of symmetrical silicon-containing dienes substituted with large steric hindrance aromatic groups and a variety of α-olefins to synthesize a series of high heat resistance and ultra-low dielectric polymer copolymer materials with excellent performance. A catalyst with excellent copolymerization ability and high cyclization selectivity for silicon-containing dienes and α-olefins is selected to study the thermal and dielectric properties of copolymers obtained by copolymerizing symmetrical silicon-containing dienes DDPS, DMPS, DMIS, DMFS or their derivatives with ethylene, propylene, 1-butene, 1-pentene, 1-hexene, etc.

[0048] The dielectric constant of all polymers tested by the resonant cavity method was found to be between 1.30 and 1.50, and the dielectric loss was less than or equal to 3.13×10 -4 Through DSC test, it can be observed that the glass transition temperature (T g =133.8~152.4℃), when the monomer is DMFS (diallylmethylfluorenylsilane), the glass transition temperature of the copolymer can reach 170.2℃, which is significantly higher than any previous reports and studies on low dielectric polymers.

[0049] In summary, the present invention provides a method for preparing a high heat-resistant and ultra-low dielectric copolymer based on a series of symmetrical silicon-containing dienes containing complex aromatic groups and low-cost α-olefins, and prepares a high heat-resistant and ultra-low dielectric copolymer having high heat resistance (T g =110.0~170.2℃, T d95 ≥414.2℃), has the lowest dielectric constant and dielectric loss among existing polymer materials (ε=1.30~1.50, tanδ≤3.13×10 -4 ). A catalyst with excellent copolymerization ability and high cyclization selectivity for silicon-containing dienes and α-olefins is selected, the copolymer composition is optimized, and efficient synthesis of copolymer materials with ultra-high comprehensive performance (high temperature resistance, high-frequency ultra-low dielectric, low dielectric loss, mechanical properties, etc.) is achieved. The present invention can significantly overcome the poor heat resistance of synthesizing non-fluorine-type polymer dielectric materials and is expected to be used in high-performance microwave / millimeter wave substrates and packaging materials.

[0050] The present invention discloses the following technical effects:

[0051] The present invention uses a single active center metal catalyst combined with a co-catalyst to synthesize a series of copolymers of symmetrical silicon-containing dienes substituted with large steric hindrance and α-olefins. According to the characteristics of the catalyst having copolymerization ability for α-olefins and silicon-containing dienes, various α-olefins are copolymerized with symmetrical silicon-containing dienes substituted with large steric hindrance. It is observed that the proportion of symmetrical silicon-containing dienes in the copolymer composition reaches 10 to 100 mol%, and a copolymer with high heat resistance and ultra-low dielectric constant can be obtained. When DDPS (diallyl diphenylsilane ) accounts for 90 mol%, the glass transition temperature of the copolymer is up to 152.4 ° C, and the dielectric constant is between 1.36 and 1.50; when DMPS (diallylmethylphenylsilane) accounts for 90 mol%, the glass transition temperature of the copolymer is up to 137.0 ° C, and the dielectric constant is 1.30 to 1.37; when the steric hindrance of the aromatic group is further increased, and the phenyl group is replaced by indenyl or fluorenyl, the glass transition temperature of the copolymer can be further increased to 170.2 ° C, and the heat resistance of the material is significantly improved. In addition, the dielectric loss of all polymers is ≤3.13×10 -4 . Finally, the mechanical properties of the copolymer and the silicon-containing diene homopolymer were compared, and it was found that the homopolymer was brittle as a whole, which was caused by the high content of ring units in the polymer main chain, which restricted the movement of the molecular chain. The copolymer had more α-olefin chain units inserted into the main chain, and the tensile strength of the material was significantly improved. It is worth noting that the high heat-resistant and ultra-low dielectric constant materials prepared by the present invention have a dielectric constant significantly lower than that of polytetrafluoroethylene (PTFE, ε≈2.1), polyimide (PI, ε>3.0), polyphenylene ether (PPE, ε≈2.7), poly-4-methyl-1-pentene (PMP, ε≈2.1) and other materials widely used in the current electronic information field, and are expected to be used in high-performance microwave / millimeter wave substrates and packaging materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0053] Figure 1 The copolymer prepared in Example 5 1 H NMR and 13 C NMR spectrum;

[0054] Figure 2 The copolymer prepared in Example 6 1 H NMR and 13 C NMR spectrum;

[0055] Figure 3 The copolymer prepared in Example 12 1 H NMR and 13 C NMR spectrum;

[0056] Figure 4 The dielectric constant scatter plots of the copolymers prepared in Examples 1, 3, 5, 8, 10, and 12;

[0057] Figure 5 The dielectric loss scatter plots of the copolymers prepared in Examples 1, 3, 5, 8, 10, and 12;

[0058] Figure 6 DSC curves of the copolymers prepared in Examples 1, 3, 5, 8, 10, and 12;

[0059] Figure 7 TGA curves of the copolymers prepared in Examples 1, 3, 8 and 10. DETAILED DESCRIPTION

[0060] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0061] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0062] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0063] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0064] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0065] It should be pointed out that the matters not described in detail in the present invention are conventional operating means in the art and are not the focus of the present invention.

[0066] As a first aspect of the present invention, the present invention provides a high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer, the structural formula of the high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer is

[0067] Wherein, R=H, CH3 or (CH2) n CH3, n is an integer from 1 to 10, R3 and R4 are selected from one of the following two situations:

[0068] Option 1: R3 = R4 = phenyl, indenyl, fluorenyl, naphthyl or anthracenyl;

[0069] Option 2: R3 = CH3, R4 = phenyl, indenyl, fluorenyl, naphthyl or anthracenyl.

[0070] As an embodiment of the present invention, the weight average molecular weight of the high heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer is (35-150)×10 4 g / mol.

[0071] As a preferred embodiment of the present invention, the content of the symmetrical silicon-containing diene substituted with a large steric hindrance aromatic group in the high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer is 10 to 100 mol %, and is not 100 mol %.

[0072] As a second aspect of the present invention, the present invention provides a method for preparing a highly heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer, comprising the following steps:

[0073] A symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group, an alpha-olefin, a catalyst, a co-catalyst, a chain transfer agent and a hydrocarbon compound solvent are mixed to obtain a mixture, which is then heated for polymerization reaction to obtain the highly heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer.

[0074] As a preferred embodiment of the present invention, the preparation method more specifically comprises the following steps:

[0075] (1) mixing a symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group, an α-olefin, a catalyst, a co-catalyst, a chain transfer agent and a hydrocarbon compound solvent to obtain a mixture, performing a polymerization reaction at 20 to 85° C. for 10 to 720 minutes, and adding ethanol to terminate the polymerization reaction to obtain a reaction solution;

[0076] (2) The reaction solution is mixed with the acidified precipitant, and the mixture is subjected to a first sedimentation, a first washing, a first filtration, a dissolution, an adsorption, a second sedimentation, a second filtration, a second washing, and a vacuum drying to obtain a high heat-resistant, ultra-low dielectric fluorine-free copolymer.

[0077] As an embodiment of the present invention, in the mixing process, the α-olefin may be mixed with part of the solvent first, the catalyst and the co-catalyst may be mixed with part of the solvent, and then the whole may be mixed.

[0078] As an embodiment of the present invention, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group includes one of diallyldiphenylsilane (DDPS), diallylmethylphenylsilane (DMPS), diallyldiindenylsilane, diallylmethylindenylsilane (DMIS), diallyldifluorenylsilane, diallylmethylfluorenylsilane (DMFS), diallyldinaphthylsilane, diallylmethylnaphthylsilane, diallyldianthracenylsilane and diallylmethylanthracenylsilane;

[0079] The α-olefin includes one of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene and 1-dodecene.

[0080] As an embodiment of the present invention, the hydrocarbon compound solvent includes one or more of benzene and its homologues, indene and its homologues, naphthalene and its homologues, alkanes and its homologues, and cycloalkanes and its homologues.

[0081] As an embodiment of the present invention, the catalyst is a single active center transition metal catalyst; the single active center transition metal catalyst is Me2Si(Ind)2ZrCl2 (structural formula is Abbreviated as Cat.4) or the structural formula is A compound, wherein R1 and R2 are selected from one of the following three situations:

[0082] Option 1: R1 = H, R2 = 2- i Pr-Ph (compound referred to as Cat. 1);

[0083] Option 2: R1 = R2 = CH3 (the compound is referred to as Cat. 2);

[0084] Option 3: R1= t Bu, R2=CH3 (the compound is abbreviated as Cat. 3).

[0085] As an embodiment of the present invention, the co-catalyst includes one or more of tripentafluorophenyl borane, triperfluorobiphenyl borane, triphenylmethyl tetrakis(pentafluorophenyl)borate ([Ph3C][B(C6F5)4]) and tert-butyltriphenylmethyl tetrakis(pentafluorophenyl)borate.

[0086] As an embodiment of the present invention, the chain transfer agent includes one or more of methylaluminoxane (MAO), modified methylaluminoxane (MMAO), ethylaluminoxane, isobutylaluminoxane, trimethylaluminum, diethylaluminum chloride, triethylaluminum, triisopropylaluminum, triisobutylaluminum, diethylzinc, diethylmagnesium, dibutylmagnesium and n-butylethylmagnesium.

[0087] As a preferred embodiment of the present invention, the co-catalyst is preferably triphenylmethyltetrakis(pentafluorophenyl)borate.

[0088] As a preferred embodiment of the present invention, the chain transfer agent is preferably triisobutylaluminum.

[0089] As an embodiment of the present invention, the concentration of the symmetrical silicon-containing diene substituted with a bulky sterically hindered aromatic group in the mixture is 0.1 to 0.2 mol / L, preferably 0.2 mol / L;

[0090] and / or, the concentration of the α-olefin in the mixture is 0.02 to 0.2 mol / L;

[0091] And / or, the concentration of the catalyst in the mixture is (1.5-2)×10 -4 mol / L, preferably 1.7×10 -4 mol / L;

[0092] And / or, the molar ratio of the catalyst to the co-catalyst is 1:1 to 2000, preferably 1:2.

[0093] And / or, the molar ratio of the catalyst to the chain transfer agent is 1:10 to 1000, preferably 1:150.

[0094] As an embodiment of the present invention, the precipitant includes one or more of ethanol, methanol, petroleum ether, ether, n-hexane, acetone, n-pentane, tetrahydrofuran and dichloromethane, preferably ethanol;

[0095] And / or, the acidification includes: mixing an acid with a precipitant, that is, the precipitant after acidification is a mixed solution of the precipitant and the acid.

[0096] As an embodiment of the present invention, the acid is hydrochloric acid with a concentration of 38 wt %, and the volume ratio of the precipitant to the hydrochloric acid is 50:1.

[0097] As a preferred embodiment of the present invention, the single active site transition metal catalyst is preferably Cat.1.

[0098] As an embodiment of the present invention, the adsorption includes: adsorption using an adsorbent; the adsorbent includes one of 100-500 mesh silica gel powder, 100-800 mesh neutral alumina, and 100-200 mesh molecular sieve, preferably 200-300 mesh neutral alumina.

[0099] As a preferred embodiment of the present invention, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallylmethylphenylsilane (DMPS), and the structural formula of the highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer is as shown in Formula I;

[0100] Or, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallylmethylindenylsilane (DMIS), and the structural formula of the highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer is as shown in Formula II;

[0101] Or, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallyldiphenylsilane (DDPS), and the structural formula of the highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer is as shown in Formula III;

[0102] Or, the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group is diallylmethylfluorenylsilane (DMFS), and the structural formula of the highly heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer is as shown in Formula IV;

[0103]

[0104] Wherein, R=H, CH3 or (CH2) n CH3, n is an integer from 1 to 10. Preferably, R=H, CH3, CH2CH3, (CH2)2CH3 or (CH2)3CH3.

[0105] As a preferred embodiment of the present invention, the properties of the high heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer include: g =110.0~170.2℃; T d95 ≥414.2℃; the dielectric constant of the copolymer is 1.30~1.50, and the dielectric loss is 2.51×10 -4 ~3.13×10 -4 .

[0106] As a third aspect of the present invention, the present invention provides the use of the above-mentioned high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer in the preparation of high-performance microwave substrates, millimeter wave substrates or packaging materials.

[0107] The structural information of the main raw materials involved in the specific implementation of the present invention is shown in Table 1.

[0108] Table 1

[0109]

[0110]

[0111]

[0112] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0113] All raw materials used in the following examples and comparative examples are common commercial products unless otherwise specified, wherein ethanol is anhydrous ethanol, the CAS number of diallyldiphenylsilane (DDPS) is 10519-88-7, and the CAS number of diallylmethylphenylsilane (DMPS) is 2633-60-5.

[0114] Catalyst Cat. 1 was synthesized according to the prior art (Angewandte Chemie 2006, 45 (20), 3278-3283).

[0115] The preparation method of diallylmethylindenylsilane (DMIS) is as follows:

[0116] Using the Schlenk experimental apparatus, under a nitrogen atmosphere, add 30g of magnesium powder (1.25mol) and 400mL of anhydrous ether (SPS) to a dry 2L three-necked flask equipped with mechanical stirring, a constant pressure dropping funnel and a spherical condenser. Measure 40mL (0.58mol) of allyl bromide (redistilled), dilute it with 500mL of anhydrous ether (SPS) and add it to the constant pressure dropping funnel. Pass condensed water, heat to 30°C, and first add a small amount of allyl bromide ether solution to the reaction bottle through the constant pressure dropping funnel. After heating to initiate the reaction, slowly add the ether solution of allyl bromide to keep the ether in a slightly boiling state. After the addition is completed, the color of the liquid gradually changes to gray-black. Continue the reaction for 3h (40°C) under heating to ensure that the reaction is complete.

[0117] Then, 47 ml (0.25 mol) of methylindenyldichlorosilane (CAS No.: 17478-29-4) was slowly added to the above reaction system through a constant pressure dropping funnel (violent heat release). After the addition was completed, the reaction was continued for 3 hours under heating and reflux at 40°C to ensure complete reaction. After the reaction was completed, a saturated aqueous solution of ammonium chloride was slowly added to the reaction system to destroy the unreacted Grignard reagent (violent heat release). The insoluble matter was removed by filtration, and the filter cake was washed three times with ether. The filtrate was extracted three times with ether, the ether layers were combined, dried over anhydrous magnesium sulfate, and then rotary evaporated to remove the ether. The obtained liquid was further distilled under reduced pressure. 50 ml of the product diallylmethylindenylsilane was obtained. Yield: 85%.

[0118] The preparation method of diallylmethylfluorenylsilane (DMFS) is the same as the preparation method of diallylmethylindenylsilane (DMIS), the only difference is that methylindenyldichlorosilane is replaced by methylfluorenyldichlorosilane (CAS No.: 164462-10-6).

[0119] Diallyldiindenylsilane, diallyldifluorenylsilane, diallyldinaphthylsilane, diallylmethylnaphthylsilane, diallyldianthracenylsilane and diallylmethylanthracenylsilane can be prepared by a synthetic route similar to that of DMIS and DMFS.

[0120] In the process of synthesizing the catalyst, the operations involved are performed by professionals familiar with the technical field in an MBraun glove box or using standard Schlenk technology under the protection of inert gas such as nitrogen or argon, unless otherwise specified. At the same time, the solvents involved in the present invention are all solvents that are anhydrous and oxygen-free after post-treatment. In addition, in the process of preparing the highly heat-resistant, ultra-low dielectric fluorine-free copolymer, all polymerization reactions must be carried out under anhydrous and oxygen-free conditions, and the glassware such as ampoules, syringes, polymerization bottles, etc. involved in the preparation steps for weighing and transferring catalysts, co-catalysts, chain transfer agents, solutions, etc. are all treated with anhydrous and oxygen-free treatment, and all operations sensitive to moisture and oxygen are performed by professionals familiar with the technical field in an MBraun glove box or using standard Schlenk technology under nitrogen protection.

[0121] Example 1

[0122] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallyldiphenylsilane / ethylene copolymer, with a structural formula as shown in Formula III, wherein R=H), comprising the following steps:

[0123] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DDPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of ethylene) of an ethylene / toluene mixed solution was added (so that the concentration of ethylene in the final mixture was 0.02 mol / L); after stabilization, the mixture was added Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), controlling the amount of toluene in the ethylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution to make the total volume of the final mixture 60 mL, and carrying out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction, adding 0.5 ml of ethanol to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallyl diphenylsilane / ethylene copolymer.

[0124] Example 2

[0125] The same as Example 1, except that the amount of DDPS used is 8 equivalents (9.6 mmol), that is, the concentration in the final mixture is 0.16 mol / L; the amount of ethylene used is 2 equivalents (2.4 mmol), that is, the concentration in the final mixture is 0.04 mol / L.

[0126] Example 3

[0127] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallyldiphenylsilane / propylene copolymer, with a structural formula as shown in Formula III, wherein R=CH3), comprising the following steps:

[0128] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DDPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of propylene) of a propylene / toluene mixed solution was added (so that the concentration of propylene in the final mixture was 0.02 mol / L); after stabilization, 100% propylene was added. Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), controlling the amount of toluene in the propylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution so that the total volume of the final mixture is 60 mL, and carrying out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 minutes; after the polymerization reaction is completed, 0.5 ml of ethanol is added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation. After sedimentation for 6 hours, it was washed and filtered, then dissolved in toluene, and adsorbed with 200-300 mesh neutral alumina to remove impurities. The reaction solution was then poured into an ethanol / hydrochloric acid solution for sedimentation for 6 hours, and then washed, filtered, and vacuum dried at 70°C to obtain a diallyl diphenylsilane / propylene copolymer.

[0129] Example 4

[0130] Same as Example 3, except that the amount of DDPS used is 8 equivalents (9.6 mmol), ie, the concentration in the final mixture is 0.16 mol / L; the amount of propylene used is 2 equivalents (2.4 mmol), ie, the concentration in the final mixture is 0.04 mol / L.

[0131] Example 5

[0132] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallyldiphenylsilane / 1-butene copolymer, with a structural formula as shown in Formula III, wherein R=CH2CH3), comprising the following steps:

[0133] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DDPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol) of 2-nitropropene was added. After stabilization, a 1-butene / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]) was added, and the amount of toluene in the 1-butene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution was controlled to make the total volume of the final mixture 60 mL, and the polymerization reaction was carried out at a temperature of 25° C. and a stirring condition of 500 rpm for 240 min; after the polymerization reaction was completed, 0.5 ml of ethanol was added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallyl diphenylsilane / 1-butene copolymer.

[0134] Example 6

[0135] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallyldiphenylsilane / 1-pentene copolymer, with a structural formula as shown in Formula III, wherein R=(CH2)2CH3), comprising the following steps:

[0136] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / LL); then 9 equivalents (10.8 mmol) of DDPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol) of 2-nitropropene was added. After stabilization, add Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), control the amount of toluene in the 1-pentene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution, make the total volume of the final mixture 60 mL, and carry out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction is completed, add 0.5 ml of ethanol to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallyl diphenylsilane / 1-pentene copolymer.

[0137] Example 7

[0138] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallyldiphenylsilane / 1-hexene copolymer, with a structural formula as shown in Formula III, wherein R=(CH2)3CH3), comprising the following steps:

[0139] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DDPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol) of 2-nitropropene was added. After stabilization, a 1-hexene / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]) was added, and the amount of toluene in the 1-hexene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution was controlled to make the total volume of the final mixture 60 mL, and the polymerization reaction was carried out at a temperature of 25° C. and a stirring condition of 500 rpm for 240 min; after the polymerization reaction was completed, 0.5 ml of ethanol was added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and dried in vacuo at 70°C to obtain a diallyl diphenylsilane / 1-hexene copolymer.

[0140] Example 8

[0141] A method for preparing a highly heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer (diallylmethylphenylsilane / ethylene copolymer, with a structural formula as shown in Formula I, wherein R=H), comprising the following steps:

[0142] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of ethylene) of an ethylene / toluene mixed solution was added (so that the concentration of ethylene in the final mixture was 0.02 mol / L); after stabilization, the mixture was added Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), controlling the amount of toluene in the ethylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution to make the total volume of the final mixture 60 mL, and carrying out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction, adding 0.5 ml of ethanol to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylphenylsilane / ethylene copolymer.

[0143] Example 9

[0144] Same as Example 8, except that the amount of DMPS used is 8 equivalents (9.6 mmol), that is, the concentration in the final mixture is 0.16 mol / L; the amount of ethylene used is 2 equivalents (2.4 mmol), that is, the concentration in the final mixture is 0.04 mol / L.

[0145] Example 10

[0146] A method for preparing a highly heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer (diallylmethylphenylsilane / propylene copolymer, with a structural formula as shown in Formula I, wherein R=CH3), comprising the following steps:

[0147] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of propylene) of a propylene / toluene mixed solution was added (so that the concentration of propylene in the final mixture was 0.02 mol / L); after stabilization, 20% propylene was added. Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), controlling the amount of toluene in the propylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution so that the total volume of the final mixture is 60 mL, and carrying out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 minutes; after the polymerization reaction is completed, 0.5 ml of ethanol is added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylphenylsilane / propylene copolymer.

[0148] Embodiment 11

[0149] Same as Example 10, except that the amount of DMPS used is 8 equivalents (9.6 mmol), ie, the concentration in the final mixture is 0.16 mol / L; the amount of propylene used is 2 equivalents (2.4 mmol), ie, the concentration in the final mixture is 0.04 mol / L.

[0150] Example 12

[0151] A method for preparing a highly heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer (diallylmethylphenylsilane / 1-butene copolymer, with a structural formula as shown in Formula I, wherein R=CH2CH3), comprising the following steps:

[0152] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol) of DMPS was added. After stabilization, a 1-butene / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]) was added, and the amount of toluene in the 1-butene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution was controlled to make the total volume of the final mixture 60 mL, and the polymerization reaction was carried out at a temperature of 25° C. and a stirring condition of 500 rpm for 240 min; after the polymerization reaction was completed, 0.5 ml of ethanol was added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylphenylsilane / 1-butene copolymer.

[0153] Embodiment 13

[0154] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallylmethylphenylsilane / 1-pentene copolymer, with a structural formula as shown in Formula I, wherein R=(CH2)2CH3), comprising the following steps:

[0155] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol) of DMPS was added. After stabilization, a 1-pentene / toluene mixed solution (containing 10 μmol of catalyst Cat.1 and 20 μmol of co-catalyst [Ph3C][B(C6F5)4]) was added, and the amount of toluene in the 1-pentene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution was controlled to make the total volume of the final mixture 60 mL, and the polymerization reaction was carried out at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction was completed, 0.5 ml of ethanol was added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylphenylsilane / 1-pentene copolymer.

[0156] Embodiment 14

[0157] A method for preparing a highly heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer (diallylmethylphenylsilane / 1-hexene copolymer, with a structural formula as shown in Formula I, wherein R=(CH2)3CH3), comprising the following steps:

[0158] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMPS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol) of DMPS was added. After stabilization, a 1-hexene / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]) was added, and the amount of toluene in the 1-hexene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution was controlled to make the total volume of the final mixture 60 mL, and the polymerization reaction was carried out at a temperature of 25° C. and a stirring condition of 500 rpm for 240 min; after the polymerization reaction was completed, 0.5 ml of ethanol was added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylphenylsilane / 1-hexene copolymer.

[0159] Embodiment 15

[0160] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallylmethylindenylsilane / ethylene copolymer, with a structural formula as shown in Formula II, wherein R=H), comprising the following steps:

[0161] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMIS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of ethylene) of an ethylene / toluene mixed solution was added (so that the concentration of ethylene in the final mixture was 0.02 mol / L); after stabilization, the mixture was added Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), controlling the amount of toluene in the ethylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution to make the total volume of the final mixture 60 mL, and carrying out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction, adding 0.5 ml of ethanol to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylindenylsilane / ethylene copolymer.

[0162] Example 16

[0163] A method for preparing a highly heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer (diallylmethylindenylsilane / propylene copolymer, with a structural formula as shown in Formula II, wherein R=CH3), comprising the following steps:

[0164] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMIS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of propylene) of a propylene / toluene mixed solution was added (so that the concentration of propylene in the final mixture was 0.02 mol / L); after stabilization, 10.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added (so that the concentration of triisobutylaluminum in the final mixture was 0.02 mol / L); then ... Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), controlling the amount of toluene in the propylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution so that the total volume of the final mixture is 60 mL, and carrying out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 minutes; after the polymerization reaction is completed, 0.5 ml of ethanol is added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours, filtered, dissolved in toluene, and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, and then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylindenylsilane / propylene copolymer.

[0165] Embodiment 17

[0166] A method for preparing a highly heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer (diallylmethylfluorenylsilane / ethylene copolymer, with a structural formula as shown in Formula IV, wherein R=H), comprising the following steps:

[0167] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMFS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of ethylene) of an ethylene / toluene mixed solution was added (so that the concentration of ethylene in the final mixture was 0.02 mol / L); after stabilization, the polymerization reaction was continued until the polymerization reaction was completed. Add Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), control the amount of toluene in the ethylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution to make the total volume of the mixed system 60 mL, and carry out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction is completed, add 0.5 ml of ethanol to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (ethanol and 38 wt% hydrochloric acid were mixed in a volume ratio of 50:1) to settle, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution to settle, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylfluorenylsilane / ethylene copolymer.

[0168] Embodiment 18

[0169] A method for preparing a highly heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer (diallylmethylfluorenylsilane / propylene copolymer, with a structural formula as shown in Formula IV, wherein R=CH3), comprising the following steps:

[0170] Using a Schlenk experimental apparatus, under a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 9 equivalents (10.8 mmol) of DMFS was added (so that the concentration in the final mixture was 0.18 mol / L), and 1 equivalent (containing 1.2 mmol of propylene) of a propylene / toluene mixed solution was added (so that the concentration of propylene in the final mixture was 0.02 mol / L); after stabilization, 10.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added (so that the concentration of triisobutylaluminum in the final mixture was 0.02 mol / L); then ... Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]), controlling the amount of toluene in the propylene / toluene mixed solution and the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution so that the total volume of the final mixture is 60 mL, and carrying out polymerization reaction at a temperature of 25°C and a stirring condition of 500 rpm for 240 minutes; after the polymerization reaction is completed, 0.5 ml of ethanol is added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (ethanol and 38 wt% hydrochloric acid were mixed in a volume ratio of 50:1) to settle, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution to settle, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylfluorenylsilane / propylene copolymer.

[0171] Comparative Example 1

[0172] Using a Schlenk experimental apparatus, in a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 12 mmol of DDPS was added (so that the concentration in the final mixture was 0.2 mol / L); after stabilization, Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]) was added, and the amount of toluene in the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution was controlled so that the total volume of the final mixture was 60 mL. The polymerization reaction was carried out at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction was completed, 0.5 ml of ethanol was added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and dried in vacuo at 70°C to obtain a diallyldiphenylsilane homopolymer.

[0173] Comparative Example 2

[0174] Using the Schlenk experimental apparatus, in a nitrogen atmosphere, 1.5 ml of a 1.0 mol / L chain transfer agent triisobutylaluminum / toluene mixed solution was added to a polymerization bottle (so that the concentration of triisobutylaluminum in the final mixture was 0.025 mol / L); then 12 mmol of DMPS was added (so that the concentration in the final mixture was 0.2 mol / L); after stabilization, Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution (containing 10 μmol catalyst Cat.1 and 20 μmol co-catalyst [Ph3C][B(C6F5)4]) was added, and the amount of toluene in the Cat.1 / [Ph3C][B(C6F5)4] / toluene mixed solution was controlled so that the total volume of the final mixture was 60 mL. The polymerization reaction was carried out at a temperature of 25°C and a stirring condition of 500 rpm for 240 min; after the polymerization reaction was completed, 0.5 ml of ethanol was added to terminate the polymerization to obtain a reaction solution. The reaction solution was slowly poured into a beaker containing 300 mL of an ethanol / hydrochloric acid mixed solution (composed of ethanol and 38 wt% hydrochloric acid mixed in a volume ratio of 50:1) for sedimentation, washed for 6 hours and filtered, then dissolved in toluene and adsorbed with 200-300 mesh neutral alumina to remove impurities, then poured into an ethanol / hydrochloric acid solution for sedimentation, then washed, filtered, and vacuum dried at 70°C to obtain a diallylmethylphenylsilane homopolymer.

[0175] Test Case

[0176] The copolymers obtained in Examples 1-18 and the homopolymers obtained in Comparative Examples 1-2 were tested for related properties. Nuclear magnetic resonance spectroscopy (NMR) was used to characterize the chemical structure of the polymers. Differential scanning calorimetry (DSC) was used to characterize the thermal properties of the polymers. High temperature gel permeation chromatography (GPC) was used to characterize the molecular weight (weight average molecular weight M) of the polymers. w , g / mol) and molecular weight distribution (PDI). 1 H and 13 C NMR was measured by Bruker-400 NMR at 25°C, TMS was used as internal standard, and the solvent was deuterated o-dichlorobenzene or deuterated 1,1,2,2-tetrachloroethane. The glass transition temperature (T g ) was measured by differential scanning calorimetry (Q2000 DSC) under the conditions of nitrogen atmosphere and a heating / cooling rate of 20°C / min. Thermogravimetric analysis was used to test the thermal decomposition temperature (T d95 ), the tester is Swiss-Mettler-TGA2, the constant temperature rise method is used, and the experiment is carried out in N2 atmosphere. The temperature rise range is set between 100-600℃, and the heating rate is kept at 10℃ / min. The decomposition temperature T of the polymer is determined by measuring the temperature at which the polymer loses 95% of its weight d95. Gel chromatography was determined using a PL GPC-220 gel permeation chromatograph. The tester was RI-Laser, PL EasiCal PS-1 was used as the standard sample, the filling column was Plgel 10μm MIXED-BLS, 1,2,4-trichlorobenzene (TCB) was used as the solvent (0.05wt% of 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 resonant cavity-vector network analyzer (Agilent, USA) was used to test the dielectric properties of the polymer at 12G Hz. A universal testing machine (Instron 3360) was used to perform a tensile test on the polymer sample at a temperature of 25°C (the tensile specimen was 10mm long, 3.4mm wide, and 0.24mm thick; the tensile rate was 10mm / min based on ISO 527-1).

[0177] Figure 1 The copolymer prepared in Example 5 1 H NMR and 13 C NMR spectrum.

[0178] Figure 2 The copolymer prepared in Example 6 1 H NMR and 13 C NMR spectrum.

[0179] Figure 3 The copolymer prepared in Example 12 1 H NMR and 13 C NMR spectrum.

[0180] The reaction conditions of Examples 1-18 and Comparative Examples 1-2 and the performance data of the obtained copolymers (DSC, GPC, TGA, resonant cavity-vector network analyzer test data) are shown in Table 2.

[0181] Table 2

[0182]

[0183] Note: a Reaction conditions; b High temperature GPC test shows; c DSC test out; d TGA test results: e 13 C NMR calculated; f The ratio of polymer output to input monomer; g Resonant cavity - vector network analyzer test; h Tensile machine tested.

[0184] Figure 4The dielectric constant scatter plots of the copolymers prepared in Examples 1, 3, 5, 8, 10 and 12 (plotted based on the data in Table 2);

[0185] Figure 5 Dielectric loss scatter plots of the copolymers prepared in Examples 1, 3, 5, 8, 10, and 12 (plotted based on the data in Table 2);

[0186] Figure 6 DSC curves of the copolymers prepared in Examples 1, 3, 5, 8, 10 and 12 (DSC curves corresponding to the data in Table 2);

[0187] Figure 7 The TGA curves of the copolymers prepared in Examples 1, 3, 8 and 10 (the TGA curves corresponding to the data in Table 2, wherein the right figure is a partial enlarged view of the left figure);

[0188] In addition to the data listed in Table 2, it was also observed through DSC testing that the polymers obtained in Examples 1-18 and Comparative Examples 1-2 all exhibited amorphous behavior.

[0189] As shown in Table 2, when Cat.1 is used to catalyze the copolymerization of DDPS (diallyldiphenylsilane) and simple olefins, the glass transition temperature of the copolymer can reach up to 152.4°C, and the dielectric constant is between 1.36 and 1.50. Furthermore, by replacing the phenyl group with indenyl or fluorenyl to increase the steric hindrance, the glass transition temperature of the copolymer can be increased to 170.2°C, and the heat resistance of the material is significantly improved, indicating that this material is effective in supplementing the thermal performance defects of dielectric polymer materials. From the perspective of the mechanical properties of the material, the symmetrical silicon-containing diene homopolymer and the copolymers prepared by copolymerizing it with ethylene, propylene, butene, 1-pentene, and 1-hexene were compared. The results showed that the homopolymer had obvious brittle characteristics, while the tensile strength of the copolymer was significantly higher than that of the homopolymer, indicating that the insertion of α-olefins in the polymer main chain has a good modification effect on the mechanical properties. The dielectric constants of the copolymers prepared by Cat.1 are all between 1.30 and 1.50, and the dielectric loss is between 10 -4 This is much lower than any previous reports and studies on low dielectric polymers.

[0190] The present invention discloses a method for preparing a high heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer material based on a symmetrical silicon-containing diene (DDPS, DMPS, DMIS, DMFS, etc.) substituted with a large steric hindrance aromatic group and a simple olefin (α-olefin). The method has very important research significance for improving the thermal stability of dielectric polymer materials and reducing the dielectric constant, and is expected to be applied in high-performance microwave / millimeter wave substrates and packaging materials.

[0191] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A high heat-resistant, ultra-low dielectric, fluorine-free silicon-containing copolymer, characterized in that: The structural formula of the high heat-resistant, ultra-low dielectric non-fluorinated silicon-containing copolymer is: Wherein, R=H, CH3 or (CH2) n CH3, n is an integer from 1 to 10, R3 and R4 are selected from one of the following two situations: Option 1: R3 = R4 = phenyl, indenyl, fluorenyl, naphthyl or anthracenyl; Option 2: R3 = CH3, R4 = phenyl, indenyl, fluorenyl, naphthyl or anthracenyl.

2. A method for preparing the high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer according to claim 1, characterized in that: The following steps are involved: A symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group, an α-olefin, a catalyst, a co-catalyst, a chain transfer agent and a hydrocarbon compound solvent are mixed to obtain a mixture, and then heated to carry out a polymerization reaction to obtain the highly heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer; The symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group includes one of diallyldiphenylsilane, diallylmethylphenylsilane, diallyldiindenylsilane, diallylmethylindenylsilane, diallyldifluorenylsilane, diallylmethylfluorenylsilane, diallyldinaphthylsilane, diallylmethylnaphthylsilane, diallyldianthracenylsilane and diallylmethylanthracenylsilane; The α-olefin includes one of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene and 1-dodecene.

3. The preparation method according to claim 2, characterized in that: The hydrocarbon compound solvent includes one or more of benzene and its homologues, indene and its homologues, naphthalene and its homologues, alkanes and its homologues, and cycloalkanes and its homologues.

4. The preparation method according to claim 2, characterized in that: The catalyst is a single active site transition metal catalyst; And / or, the co-catalyst includes one or more of tripentafluorophenyl alkane borane, triperfluorobiphenyl borane, triphenylmethyl tetrakis(pentafluorophenyl) borate and tert-butyltriphenylmethyl tetrakis(pentafluorophenyl) borate; And / or, the chain transfer agent includes one or more of methylaluminoxane, modified methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, trimethylaluminum, diethylaluminum chloride, triethylaluminum, triisopropylaluminum, triisobutylaluminum, diethylzinc, diethylmagnesium, dibutylmagnesium and n-butylethylmagnesium.

5. The preparation method according to claim 2, characterized in that: The concentration of the symmetrical silicon-containing diene substituted with a large sterically hindered aromatic group in the mixture is 0.1 to 0.2 mol / L; and / or, the concentration of the α-olefin in the mixture is 0.02 to 0.2 mol / L; And / or, the concentration of the catalyst in the mixture is (1.5-2)×10 -4 mol / L; and / or, the molar ratio of the catalyst to the co-catalyst is 1:1 to 2000; And / or, the molar ratio of the catalyst to the chain transfer agent is 1:10-1000.

6. The preparation method according to claim 2, characterized in that: The polymerization reaction temperature is 20-85° C. and the reaction time is 10-720 min.

7. The preparation method according to claim 2, characterized in that: After the polymerization reaction is completed, the steps of adding ethanol to terminate the polymerization reaction to obtain a reaction solution, mixing the reaction solution with an acidified precipitant, and performing a first sedimentation, a first washing, a first filtration, a dissolution, an adsorption, a second sedimentation, a second filtration, a second washing, and a vacuum drying step are also included.

8. The preparation method according to claim 7, characterized in that: The precipitant includes one or more of ethanol, methanol, petroleum ether, ether, n-hexane, acetone, n-pentane, tetrahydrofuran and dichloromethane; And / or, the acidification comprises: mixing an acid with a precipitant.

9. The preparation method according to claim 4, characterized in that: The single active center transition metal catalyst is Me2Si(Ind)2ZrCl2 or has the structural formula A compound, wherein R1 and R2 are selected from one of the following three situations: Option 1: R1 = H, R2 = 2- i Pr-Ph; Option 2: R1=R2=CH3; Option 3: R1= t Bu, R2=CH3.

10. Use of the high heat-resistant, ultra-low dielectric fluorine-free silicon-containing copolymer according to claim 1 in the preparation of high-performance microwave substrates, millimeter wave substrates or packaging materials.

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