CN110563955A

CN110563955A - Liquid curable metal-based polycarbosilane and preparation method thereof

Info

Publication number: CN110563955A
Application number: CN201911016637.9A
Authority: CN
Inventors: 莫高明; 宋建融; 陈海俊; 何流; 黄庆; 黄政仁
Original assignee: Ningbo Institute of Material Technology and Engineering of CAS
Current assignee: Ningbo Institute of Material Technology and Engineering of CAS
Priority date: 2019-10-24
Filing date: 2019-10-24
Publication date: 2019-12-13
Anticipated expiration: 2039-10-24
Also published as: CN110563955B

Abstract

The invention discloses liquid curable metal-based polycarbosilane and a preparation method thereof. The preparation method comprises the following steps: in a closed reaction container, carrying out a first reaction on polysilanesilane and a metal-based compound to generate liquid metal-based polycarbosilane, wherein the polysilanesilane is a low molecular product obtained by pyrolysis of polydimethylsiloxane, is in a liquid state at room temperature, and has a molecular weight of less than 1000 g/mol; and carrying out a second reaction on the liquid metal-based polycarbosilane, the organosilicon compound containing C ═ C bonds and the catalyst to obtain the liquid curable metal-based polycarbosilane. The liquid curable metal-based polycarbosilane has the advantages of relatively simple preparation process, long storage time, thermocuring, capability of being applied to the fields of preparing silicon carbide ceramic-based composite materials, high-temperature resistant coatings, adhesives and the like, capability of improving the temperature resistance of the final ceramic due to the introduction of metal elements, capability of endowing the ceramic with certain functional attributes, such as wave absorption and the like, and good application prospect.

Description

Liquid curable metal-based polycarbosilane and preparation method thereof

Technical Field

The invention belongs to the technical field of ceramic precursor preparation, and particularly relates to liquid curable metal-based polycarbosilane and a preparation method thereof.

Background

polymer-converted Ceramics (PDCs) are organic polymers that are prepared by chemical synthesis and can be converted into ceramic materials by pyrolysis, and are converted into thermosetting polymers by crosslinking and curing, and then are pyrolyzed to obtain Ceramics, which is one of the hot materials studied internationally at present. Compared with the traditional ceramic preparation process, the PDCs have the advantages of capability of designing a precursor structure, good manufacturability and machinability, lower preparation temperature and the like. Silicon carbide (SiC) ceramics have excellent characteristics of high temperature resistance, oxidation resistance, high thermal conductivity, corrosion resistance and the like, and have important application in the fields of aerospace, heat exchangers, nuclear power, high-speed brake discs and the like.

Polycarbosilane (PCS) is an important precursor of silicon carbide ceramics and is generally obtained by performing a cracking and rearrangement reaction on Polydimethylsilane (PDMS) at 400-500 ℃ under the protection of inert gas. PCS is solid at normal temperature, when the PCS is used as a ceramic precursor, the PCS is generally dissolved in an organic solvent, and the ceramic matrix composite is prepared through a plurality of dipping-cracking processes, so that the actual ceramic yield is low, and the preparation period is long. M.Kotani et al (Composite Science and Technology,2002,62:2179-2188) prepare high performance SiC using Polyvinylsilane (PVS) as a precursor and adding SiC micropowder_fa/SiC composite material. A.Kohyama et al (Jou)rn of Nuclear Materials,2000,283-287:565-569) of Polymethylsilane (PMS) and PCS mixed in a certain proportion as precursors can obtain SiC ceramic matrix with near stoichiometric ratio. Polycarbosilane (AHPCS) containing reactive vinyl groups, synthesized by Starfire corporation (US 5153295(P),1992), is liquid at room temperature, self-crosslinks on heating and cures to yield a near-stoichiometric ceramic precursor. The liquid precursor has many advantages, and can also have the defects of complex preparation route, higher cost and the like. Liquid hyperbranched polycarbosilane (LHBPCS) is developed by units such as national building and door university (functional materials, 2010, 12 (41): 2166-2168), Chinese institute of national Ningbo materials (Journal of the American Ceramic Society,2018: 1-8; CN201811139445.2) and the like, and the Ceramic with near stoichiometric ratio is obtained after high-temperature firing, and meanwhile, the problems of long preparation route, high cost, short storage life and the like exist. Lizonogen, Wangzanyuan, Yuanyuan (organosilicon material, 2010, 24 (2): 85-88; Ceramics International, 2019: 45: 7044-7048; CN201810433805.3), etc. uses LPCS and siloxane containing vinyl as raw material to prepare liquid polycarbosilane precursor (LPVCS) containing Si-H and C-C groups, and has the advantages of low cost, high ceramic yield and long storage time, etc., and is used for preparing SiC_fa/SiC composite material. Since the final product is a Si-O-C ceramic, the higher oxygen content also limits higher temperature use.

Foreign elements such as Al, Ti, Zr, B, Fe, La, Y and the like are introduced into the PCS, so that the coarsening of beta-SiC crystal grains in the high-temperature ceramic process can be effectively inhibited, the compactness is increased, and the PCS has higher high-temperature resistance. The introduction of Ti, Zr and Fe can also enable the material to have wave-absorbing property and improve the stealth performance (silicate science, 2003, 31 (4): 371-378; polymer material science and engineering, 2007,23 (3): 1-5). The introduction of heterogeneous elements into the liquid curable PCS also has a similar effect. For example, the liquid oxygen-free type poly zirconium carbosilane or poly titanium carbosilane (CN201310237094. X; CN201310238997.X) is prepared by the binary or ternary copolymerization of chloromethyl silane and zirconocene dichloride or titanocene dichloride of the same people as the tera-chamomile and the like, so that the prepared ceramic has lower resistivity and higher dielectric loss; and the liquid state oxygen-free polyferric carbosilane is prepared by taking oxygen-free vinyl ferrocene as an iron source and reacting with the liquid state hyperbranched polycarbosilane, so that the problems of nonuniform dispersion of iron elements and the like are solved (CN201310236851.1), and the technology for preparing the liquid state metal-based polycarbosilane has the defects of sensitivity of raw materials to air and water, short storage time and the like.

Disclosure of Invention

The invention mainly aims to provide a liquid curable metal-based polycarbosilane and a preparation method thereof, so as to overcome the defects in the prior art.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following steps:

The embodiment of the invention provides a preparation method of liquid curable metal-based polycarbosilane, which comprises the following steps:

In a closed reaction container, carrying out a first reaction on polysilanesilane and a metal-based compound to generate liquid metal-based polycarbosilane, wherein the polysilanesilane is a low molecular product obtained by pyrolysis of polydimethylsiloxane, is in a liquid state at room temperature, and has a molecular weight of less than 1000 g/mol;

And (3) carrying out a second reaction on a uniformly mixed reaction system containing the liquid metal-based polycarbosilane, the organosilicon compound containing C ═ C bonds and the catalyst to obtain the liquid curable metal-based polycarbosilane.

In some embodiments, the liquid metal-based polycarbosilane is liquid at room temperature, contains a metal element in a molecular structure, and is represented by-CH₂SiHCH₃-is a basic structural unit with a molecular weight of less than 1500 g/mol.

In some embodiments, the metal element includes any one or a combination of two or more of aluminum, iron, zirconium, titanium, cobalt, nickel, niobium, yttrium, beryllium, lanthanum, magnesium, and calcium, but is not limited thereto.

Embodiments of the present invention also provide liquid curable metal-based polycarbosilanes prepared by the foregoing methods.

Compared with the prior art, the liquid precursor is prepared by taking the liquid metal-based polycarbosilane and the organosilicon compound containing C-C bonds as raw materials, mixing the raw materials according to a certain proportion and adding the catalyst, and has the advantages of relatively simple preparation process, longer storage time and thermocuring. The liquid precursor can be applied to the fields of preparing silicon carbide ceramic matrix composite materials, high-temperature resistant coatings, adhesives and the like by a precursor impregnation cracking (PIP) method, and has the following beneficial effects:

1) According to the invention, metal elements are introduced into the precursor in a chemical bond combination mode, so that the problems of uneven element distribution, phase splitting of ceramic products and the like can be solved;

2) The liquid precursor is obtained by multi-component step-by-step reaction, so that the content of each element in the precursor is conveniently adjusted to obtain a target ceramic product;

3) Relevant metal base elements such as Al, La, Y and the like are introduced into the precursor, so that the coarsening of beta-SiC grains can be effectively inhibited in the high-temperature ceramic process, the compactness is increased, and the precursor has higher high-temperature resistance; related metal elements such as Ti, Zr, Fe and the like are introduced into the precursor, so that the functional properties of the final ceramic can be improved, such as the resistivity of the ceramic is reduced, the dielectric loss is improved, the wave-absorbing property of the ceramic is enhanced, and the application field of the ceramic is widened.

drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic representation of a liquid aluminum-nitrogen-containing polycarbosilane precursor prepared in example 1 of the present invention (left) and a cured gel (right).

FIG. 2 is an infrared spectrum of a liquid aluminum nitrogen containing polycarbosilane precursor (LSiAlCN) and a solidified gel (SiAlCN) prepared in example 1 of the present invention.

FIG. 3 is a graph showing the thermogravimetric analysis of the gel body after curing of the polycarbosilane containing aluminum nitrogen in example 1 of the present invention.

Detailed Description

In view of the current situation and the existing problems of polycarbosilane and the preparation method thereof in the prior art, the inventors of the present invention have made long-term research and great practice to provide the technical scheme of the present invention. The technical solution, its implementation and principles, etc. will be further explained as follows.

One aspect of an embodiment of the present invention provides a method for preparing a liquid curable metal-based polycarbosilane, comprising:

In some embodiments, the liquid metal-based polycarbosilane is prepared by reacting a polycarbosilane with a metal-based compound in a closed system, is liquid at room temperature, and has a molecular structure containing a metal element represented by-CH₂SiHCH₃-is a basic structural unit with a molecular weight of less than 1500 g/mol.

in a preferred embodiment, the preparation method comprises the steps of firstly, taking the polysilanesilane and the metal-based compound as raw materials, directly synthesizing the liquid metal-based polycarbosilane in a closed container, then mixing the liquid metal-based polycarbosilane with the organosilicon compound containing C ═ C bonds according to a certain proportion, and adding a catalyst to prepare the catalyst.

Preferably, the metal element includes any one or a combination of two or more of aluminum, iron, zirconium, titanium, cobalt, nickel, niobium, yttrium, beryllium, lanthanum, magnesium, and calcium, but is not limited thereto.

In a preferable embodiment, the mass ratio of the metal-based compound to the polysilanesilane is 0.5 to 10: 100, namely the dosage of the metal-based compound is 0.5 to 10 percent of the mass of the polysilanesilane.

In a preferable scheme, the temperature of the first reaction of the poly silicon carbon silane and the metal-based compound is 250-350 ℃.

In a preferable embodiment, the time for the first reaction of the polysilanesilane and the metal-based compound is 0.5 to 10 hours.

As one of preferable embodiments, the metal-based compound includes any one or a combination of two or more of aluminum acetylacetonate, aluminum alkoxide, iron acetylacetonate, ferrocenes, zirconium acetylacetonate, titanium acetylacetonate, cobalt acetylacetonate, nickel acetylacetonate, niobium acetylacetonate, yttrium acetylacetonate, beryllium acetylacetonate, lanthanum acetylacetonate, magnesium acetylacetonate, calcium acetylacetonate, and the like, but is not limited thereto.

As one of preferable schemes, the preparation method specifically comprises: placing the poly silicon carbon silane and the metal-based compound in a closed reaction container, enabling the closed reaction container to be in a vacuum state or a protective atmosphere state, and then carrying out the first reaction.

Further, the protective atmosphere comprises a nitrogen atmosphere and/or an inert gas atmosphere.

As one of preferable embodiments, the C ═ C bond-containing organosilicon compound includes any one or a combination of two or more of organosilane, organosiloxane, organosilazane, and the like, but is not limited thereto.

Further, the organosilane includes any one or a combination of two or more of trivinylsilane, tetravinylsilane, phenyltrivinylsilane, methyltrivinylsilane, triallylsilane, tetraallylsilane, and the like, but is not limited thereto.

further, the organosiloxane may include any one or a combination of two or more of trimethyltrivinylcyclotrisiloxane, tetramethyltetravinylcyclotetrasiloxane, pentamethylpentavinylcyclopentasiloxane, polymethylvinylsiloxane, and the like, but is not limited thereto.

Further, the organosilazane includes, but is not limited to, trimethyltrivinylcyclotrisilazane, tetramethyltetravinylcyclotetrasilazane, and the like.

As one of preferable modes, the mass ratio of the liquid metal-based polycarbosilane to the organosilicon compound containing C ═ C bonds is 100: 20-100: 90.

In a preferred embodiment, the temperature of the second reaction between the liquid metal-based polycarbosilane and the organosilicon compound containing a C ═ C bond is 0 to 80 ℃.

In a preferred embodiment, the second reaction time of the liquid metal-based polycarbosilane and the organosilicon compound containing a C ═ C bond is 1 to 300 min.

As one of preferable modes, the catalyst includes a hydrosilylation catalyst, for example, preferably includes any one or a combination of two or more of chloroplatinic acid, chloroplatinic acid-amine, Karstedt's catalyst, Wilkinson's catalyst, azobisisobutyronitrile, azobisisoheptonitrile, dibenzoyl peroxide, dicumyl peroxide, and the like, but is not limited thereto.

Further, the mass ratio of the catalyst to the liquid metal-based polycarbosilane is 0.001-1: 100, namely, the mass ratio of the catalyst to the liquid metal-based polycarbosilane is 0.001 per thousand to 1 percent.

in another aspect of embodiments of the present invention, there is also provided a liquid curable metal-based polycarbosilane prepared by the foregoing method.

In conclusion, the preparation method of the liquid curable metal-based polycarbosilane disclosed by the invention is formed by multi-component step-by-step reaction, so that the content of each element in the precursor is conveniently adjusted to obtain a target ceramic product; the precursor is in a liquid state at room temperature, the preparation process is relatively simple, the storage time is long, and the precursor can be thermally cured and can be applied to the fields of preparation of silicon carbide ceramic matrix composites, high-temperature resistant coatings, adhesives and the like. Moreover, because the metal elements are introduced, the temperature resistance of the final ceramic is improved, and certain functional attributes such as wave absorption and the like can be endowed, so that the ceramic has a good application prospect.

The technical scheme of the invention is further explained in detail by a plurality of embodiments and the accompanying drawings. It is to be noted that the following examples are intended to facilitate the understanding of the present invention, and do not set forth any limitation thereto.

example 1

the polydimethylsiloxane is subjected to pyrolysis to obtain the polysilacarbosilane, the molecular weight of which is 450g/mol and is liquid at room temperature. Adding 500g of liquid silicon carbosilane and 30g of aluminum acetylacetonate into a closed device, replacing the kettle with high-purity nitrogen for three times, and sealing the device; then, starting to heat up to 300 ℃ at a certain heating rate, and stopping after reacting for 2 h. Taking out the reactant liquid polyaluminocarbosilane LPACS when the temperature is reduced to the room temperature state;

Mixing the LPAS 100g and 75g of tetramethyltetravinylcyclotetrasilazane, adding 0.01g of chloroplatinic acid, stirring uniformly, and reacting at 80 ℃ for 1min to obtain the liquid curable aluminum-nitrogen-containing polysilazane LSiAlCN.

And curing the LSiAlCN for 1-3h at 200-300 ℃ in a nitrogen atmosphere to obtain the polysilazane gel SiAlCN containing aluminum nitrogen.

The photographs of the prepared LSiAlCN and the cured SiAlCN are shown in fig. 1. The viscosity of LSiAlCN was 35 mPaS as measured by a viscometer. FIG. 2 is an FTIR spectrum of the precursor LSiAlCN and the gelled body SiAlCN. As can be seen from FIG. 2, the precursor was 2100cm after curing by crosslinking^-1At a peak of Si-H, 1600cm^-1C ═ C peak at (C), and 3050cm^-1Where CH, etc. are all significantly reduced or eliminated, indicating that a hydrosilation chemical reaction has occurred. After crosslinking and curing in N₂The thermal weight loss curve under the atmosphere is shown in figure 3, and the ceramic yield at 1000 ℃ is more than 70%.

The LSiAlCN precursor is suitable for being used as a precursor of aluminum-containing SiCN ceramic.

example 2

500g of the liquid silicon carbosilane and 20g of the liquid zirconium acetylacetonate in the embodiment 1 are added into a closed device, and the device is sealed after the kettle is replaced by high-purity nitrogen for three times; then, starting temperature rise, raising the temperature to 350 ℃ at a certain temperature rise rate, and stopping reaction after 0.5 h. When the temperature is reduced to the room temperature state, taking out the reactant liquid poly zirconium carbon silane LPZCS;

mixing LPZCS100g and tetramethyltetravinylcyclotetrasiloxane 90g, adding chloroplatinic acid 0.02g, stirring well, and reacting at 70 deg.C for 10min to obtain liquid curable aluminum-oxygen-containing polysiloxane LSiZOC.

And curing the LSiZOC for 1-3h at 200-300 ℃ in a nitrogen atmosphere to obtain the zirconium-containing oxypolysilazane gel SiZOC.

The viscosity of LSiZOC was measured by a viscometer to be 50 mPaS, and the ceramic yield of the gel at 1000 ℃ was 75% by thermogravimetric analysis under a nitrogen atmosphere.

The LPZOC precursor is suitable for being used as a precursor of zirconium-containing SiCO ceramic.

Example 3

500g of the liquid silicon carbosilane, 20g of lanthanum acetylacetonate and 20g of yttrium acetylacetonate in the embodiment 1 are added into a closed device, and the closed device is sealed after the kettle is replaced by high-purity nitrogen for three times; then, the temperature rise is started, the temperature rises to 305 ℃ at a certain temperature rise rate, and the reaction is stopped after 4 hours. When the temperature is reduced to the room temperature state, taking out the liquid poly-lanthanum-yttrium carbosilane LPLaYCS of the reactant;

Mixing LPLaYCS100g and 20g of tetraenylsilane, adding 0.0001g of Karstedt catalyst, stirring uniformly, and reacting at 60 ℃ for 50min to obtain liquid curable lanthanum-yttrium-containing polysilazane LSiLaYC.

And curing the LSiLaYC for 1-5h at 200-300 ℃ in a nitrogen atmosphere to obtain the polysilazane gel SiLaYC containing lanthanum and yttrium.

the viscosity of LSiLaYC was measured by a viscometer to be 45 mPa.S, and the ceramic yield of the gel at 1000 ℃ was 76% by thermogravimetric analysis under a nitrogen atmosphere.

The LSiLaYC precursor is suitable for being used as a precursor of lanthanum-yttrium-containing SiC ceramics.

Example 4

500g of the liquid silicon carbosilane, 10g of aluminum acetylacetonate, 10g of yttrium acetylacetonate, 10g of magnesium acetylacetonate and 10g of calcium acetylacetonate, which are obtained in the step 1, are added into a closed device, and the closed device is sealed after the kettle is replaced by high-purity nitrogen for three times; then, the temperature is raised to 320 ℃ at a certain heating rate, and the reaction is stopped after 3 hours. When the temperature is reduced to the room temperature state, taking out the reactant liquid state polycarbosilane LPAlYMGCS containing aluminum, yttrium, magnesium and calcium;

Mixing the LPAlYMGCS100g and 75g of tetramethyltetravinylsiloxane, adding 0.01g of chloroplatinic acid catalyst, stirring uniformly, and reacting at 40 ℃ for 200min to obtain the liquid curable aluminum-yttrium-magnesium-calcium-containing polysilazane LSiAlYMGC.

And curing the LSiAlYMGC for 1-5h at 200-300 ℃ in a nitrogen atmosphere to obtain the polysilicane gel SiAlYMGC containing aluminum, yttrium, magnesium and calcium.

The viscosity of LSiAlYMGC was measured by a viscometer to be 60 mPaS, and the ceramic yield of the gel at 1000 ℃ was 78% by thermogravimetric analysis under a nitrogen atmosphere.

The LSiAlYMGC precursor is suitable for being used as a precursor of SiCO ceramic containing aluminum, yttrium, magnesium and calcium.

Example 5

500g and 50g of the liquid silicon carbosilane and the liquid iron acetylacetonate in the embodiment 1 are added into a closed device, and the device is sealed after the kettle is replaced by high-purity nitrogen for three times; then, starting to heat up to 300 ℃ at a certain heating rate, and stopping after reacting for 3 h. When the temperature is reduced to the room temperature state, taking out the reactant liquid state iron-containing polycarbosilane LPFeCS;

Mixing the LPFeCS100g and 50g of tetraallylsilane, adding 0.002g of chloroplatinic acid catalyst and 1g of azobisisobutyronitrile catalyst, stirring uniformly, and reacting at 30 ℃ for 200min to obtain liquid curable iron-containing polysilazane LSiFeC.

And curing the LSiFeC for 1-5h at 50-200 ℃ in a nitrogen atmosphere to obtain the iron-containing polysilazane gel SiFeC.

The viscosity of LSiFeC was measured by a viscometer to be 70 mPa.S, and the ceramic yield of the gel at 1000 ℃ was 80% by thermogravimetric analysis under a nitrogen atmosphere.

The precursor of LSiFeC is suitable for being used as a precursor of iron-containing SiC ceramic.

Example 6

500g of the liquid silicon carbosilane and 2.5g of the ferric acetylacetonate in the embodiment 1 are added into a closed device, and the device is sealed after the kettle is replaced by high-purity nitrogen for three times; then, starting temperature rise, raising the temperature to 250 ℃ at a certain temperature rise rate, and stopping reaction after 10 hours. When the temperature is reduced to the room temperature state, taking out the reactant liquid state of the iron-aluminum-containing polycarbosilane LPFeAlCS;

Mixing the LPFeCS100g and the polymethylvinylsiloxane 30g, adding chloroplatinic acid catalyst 0.02g, stirring uniformly, and reacting at 0 ℃ for 300min to obtain the liquid curable iron-aluminum-containing polysiloxane LSiFeAlOC.

and curing the LSiFeAlOC for 1-5h at 100-300 ℃ in a nitrogen atmosphere to obtain the iron-aluminum-containing polysiloxane gel SiFeAlOC.

The viscosity of LSiFeAlOC was 45 mPa.S as determined by viscometer, and the ceramic yield of SiFeAlOC gel at 1000 ℃ was 71% as determined by thermogravimetric analysis under nitrogen atmosphere.

the LSiFeAlOC precursor is suitable as a precursor of iron-aluminum-containing SiCO ceramics.

the aspects, embodiments, features and examples of the present invention should be considered as illustrative in all respects and not intended to be limiting of the invention, the scope of which is defined only by the claims. Other embodiments, modifications, and uses will be apparent to those skilled in the art without departing from the spirit and scope of the claimed invention.

The use of headings and chapters in this disclosure is not meant to limit the disclosure; each section may apply to any aspect, embodiment, or feature of the disclosure.

Throughout this specification, where a composition is described as having, containing, or comprising specific components or where a process is described as having, containing, or comprising specific process steps, it is contemplated that the composition of the present teachings also consist essentially of, or consist of, the recited components, and the process of the present teachings also consist essentially of, or consist of, the recited process steps.

It should be understood that the order of steps or the order in which particular actions are performed is not critical, so long as the teachings of the invention remain operable. Further, two or more steps or actions may be performed simultaneously.

In addition, the inventors of the present invention have also made experiments with other materials, process operations, and process conditions described in the present specification with reference to the above examples, and have obtained preferable results.

While the invention has been described with reference to illustrative embodiments, it will be understood by those skilled in the art that various other changes, omissions and/or additions may be made and substantial equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

1. a method for preparing a liquid curable metal-based polycarbosilane, comprising:

2. the method of claim 1, wherein: the liquid metal-based polycarbosilane is liquid at room temperature, contains metal elements in a molecular structure and is prepared from-CH₂SiHCH₃-is a basic structural unit having a molecular weight of less than 1500 g/mol; preferably, the metal element includes any one or a combination of two or more of aluminum, iron, zirconium, titanium, cobalt, nickel, niobium, yttrium, beryllium, lanthanum, magnesium and calcium elements.

3. The method of claim 1, wherein: the mass ratio of the metal-based compound to the poly silicon carbosilane is 0.5-10: 100.

4. The method of claim 1, wherein: the temperature of the first reaction is 250-350 ℃; and/or the time of the first reaction is 0.5-10 h.

5. The method of claim 1, wherein: the metal-based compound comprises any one or combination of more than two of aluminum acetylacetonate, aluminum alkoxide, ferric acetylacetonate, ferrocence, zirconium acetylacetonate, titanium acetylacetonate, cobalt acetylacetonate, nickel acetylacetonate, niobium acetylacetonate, yttrium acetylacetonate, beryllium acetylacetonate, lanthanum acetylacetonate, magnesium acetylacetonate and calcium acetylacetonate.

6. the method according to claim 1, comprising: placing the poly silicon carbon silane and the metal-based compound in a closed reaction container, enabling the closed reaction container to be in a vacuum state or a protective atmosphere state, and then carrying out the first reaction; preferably, the protective atmosphere comprises a nitrogen atmosphere and/or an inert gas atmosphere.

7. The method of claim 1, wherein: the organosilicon compound containing C ═ C bonds comprises any one of organosilane, organosiloxane and organosilazane or a combination of two or more of organosilane; preferably, the organosilane comprises any one or a combination of more than two of trivinylsilane, tetravinylsilane, phenyltrivinylsilane, methyltrivinylsilane, triallylsilane and tetraallylsilane; preferably, the organosiloxane comprises any one or a combination of more than two of trimethyl trivinyl cyclotrisiloxane, tetramethyl tetravinyl cyclotetrasiloxane, pentamethyl pentavinyl cyclopentasiloxane and polymethylvinylsiloxane; preferably, the organosilazane comprises trimethyltrivinylcyclotrisilazane and/or tetramethyltetravinylcyclotetrasilazane.

8. The method of claim 1, wherein: the mass ratio of the liquid metal-based polycarbosilane to the organosilicon compound containing C ═ C bonds is 100: 20-100: 90, respectively;

And/or the catalyst comprises a hydrosilylation catalyst, preferably comprises any one or a combination of more than two of chloroplatinic acid, chloroplatinic acid-amine, Karstedt catalyst, Wilkinson's catalyst, azobisisobutyronitrile, azobisisoheptonitrile, dibenzoyl peroxide and dicumyl peroxide;

and/or the mass ratio of the catalyst to the liquid metal-based polycarbosilane is 0.0001-1: 100.

9. The method of claim 1, wherein: the temperature of the second reaction is 0-80 ℃; and/or the time of the second reaction is 1-300 min.

10. A liquid curable metal-based polycarbosilane prepared by the process of any one of claims 1-9.