CN110540648A - Organosiloxane containing benzocyclobutene group and its preparation and application - Google Patents

Abstract

The invention provides an organosiloxane containing a benzocyclobutene group and its preparation and application. Specifically, the invention provides an organosiloxane containing a benzocyclobutene unit. The siloxane has a siloxane backbone, and has benzocyclobutene substituents directly attached to the silicon atoms of the siloxane backbone. The organosilicon resin of the present invention can undergo cross-linking and polymerization by heating, and the cross-linking product has good electrical properties and heat resistance, and the preparation method is simple, and is suitable for the electrical and electronic industry as an insulating coating layer and packaging material for electronic components. , It can also be used as a crosslinking agent for high temperature vulcanized silicone rubber.

Description

Organosiloxane containing benzocyclobutene group and its preparation and application

This application is the application number 201410625423.2, the filing date is November 7, 2014, and the divisional application of the Chinese application titled "organosiloxane containing benzocyclobutene group and its preparation and application".

technical field

The invention belongs to the field of manufacturing high-performance polymer monomers, and in particular relates to a direct heat-curable organosiloxane containing benzocyclobutene groups and a preparation method thereof.

Background technique

Among the known thermosetting resins, the benzocyclobutene-based resin molecule has been widely used in aerospace because it can be cured by ring-opening when heated to form a body-shaped polymer, and the cured product has excellent heat resistance and dimensional stability. Aviation, microelectronics, military and civil and other fields.

On the other hand, silicone resins have high heat resistance, easy processing and excellent optical properties, and have been widely used in many industrial sectors. Typically, however, silicone resins need to be crosslinked in order to be useful. Commonly used cross-linking methods generally include hydrosilylation and free radical chain extension, and in most cases, such cross-linking methods either require a catalyst (metal platinum) or an initiator.

Combining benzocyclobutene and silicone resin, utilizing the feature of direct thermal curing of benzocyclobutene, can obtain the silicone resin that can be directly thermally cured. Taking advantage of this feature, many researchers have developed a variety of silicon-containing benzocyclobutenes. The benzocyclobutene monomer containing olefin and silicon developed by Dow Company (glass fiber reinforced plastic/composite material, 2005 No. 4, 16-19.) is shown in the following formula:

However, this monomer has small molecular weight, low melting point, and poor film-forming properties, so it needs to be prepolymerized to form a prepolymer with a certain molecular weight:

Yang Shiyong et al reported the monomer represented by the following formula (J.Polym.Sci.Polym.Chem.2009,47,6246-6258):

These monomers are actually improvements to Dow's monomers by introducing phenylsilane to improve the heat resistance of the polymer. However, the above-mentioned monomers also have the disadvantages of small molecular weight, low melting point, poor film-forming property, and the need for prepolymerization during use.

Yang Junxiao and others reported the monomer represented by the following formula (Chinese invention patent application numbers 200810044584.7 and 201110092603.5):

After polymerization of these monomers, high temperature resistant materials can be obtained. Further, they obtained a polymer with a main chain of siloxane and a side chain containing thermosetting benzocyclobutene through hydrosilylation (Chinese invention patent application number 201110367893.X):

However, the aforementioned organosilicon monomers and organosilicon resins containing benzocyclobutene units have the problems of harsh synthesis conditions, difficulty in obtaining starting materials, or high cost. Especially the first and second monomers need to use palladium-catalyzed HECK reaction during polymerization. On the one hand, the palladium catalyst is expensive, and metal ligands are also used in the reaction process; on the other hand, the yield of this type of reaction is generally not tall. In this way, the cost of the final silicone resin is increased, and its application is largely limited.

In addition, in the benzocyclobutene-containing organosiloxane prepared by the coupling reaction, the benzocyclobutene unit is not directly connected to the main chain of the siloxane, but is connected through a carbon chain, resulting in its Thermal stability cannot be improved. In addition, the above-mentioned reaction also has the problem that the degree of reaction is difficult to control.

To sum up, there is an urgent need in this field to develop a silicone monomer containing benzocyclobutene units and a corresponding silicone resin with low preparation cost and mild synthesis conditions.

Contents of the invention

The object of the present invention is to provide an organosilicon monomer containing benzocyclobutene unit and corresponding silicone resin with low preparation cost and mild synthesis conditions.

The first aspect of the present invention provides an organosiloxane having a siloxane main chain and a benzocyclobutenyl group directly connected to the silicon atom of the siloxane main chain.

In another preferred embodiment, ≥30% of the silicon atoms on the main chain of the siloxane have benzocyclobutene substituents directly connected to Si.

In another preferred embodiment, ≥50% (preferably 70-100%, more preferably 90-100%) of the silicon atoms on the main chain of the siloxane have benzocyclobutenyl groups directly linked to Si.

In another preferred example, the main chain of the siloxane has a structure of formula A;

in,

x is a positive integer ≥ 2 (preferably 2-200);

Each R is independently selected from the group consisting of:

(a) H;

(b) substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein the substitution means that one or more hydrogen atoms on the group are replaced by a substituent selected from the following group: Halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1 to 3 hydrogen atoms on the benzene ring substituted by substituents selected from the group below: Halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; said substitution means that one or more hydrogen atoms on the group are substituted by a substituent selected from the following group: halogen, C1～C4 alkyl, C1～C4 haloalkane Base, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted phenyl;

(d) benzocyclobutenyl;

Also, at least one R is benzocyclobutenyl.

In another preferred example, the benzocyclobutenyl is

In another preferred example, each silicon atom on the siloxane main chain has the benzocyclobutenyl group.

In another preferred example, the organosiloxane is a resin.

In another preferred example, the organosiloxane has a refractive index of 1.5-1.6.

In another preferred example, the siloxane main chain includes a straight chain main chain and/or a branched main chain, preferably a straight chain main chain.

In another preferred example, the organosiloxane has the structure shown in the following formula I:

Wherein, n is a positive integer ≥ 2 (preferably n=2～100, more preferably n=2～50, most preferably n=2～20);

Each R is independently selected from the group consisting _of :

(a) H;

(b) substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein the substitution means that one or more hydrogen atoms on the group are replaced by a substituent selected from the following group: Halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1 to 3 hydrogen atoms on the benzene ring substituted by substituents selected from the group below: Halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; said substitution means that one or more hydrogen atoms on the group are substituted by a substituent selected from the following group: halogen, C1～C4 alkyl, C1～C4 haloalkane group, C2-C4 alkenyl group, C2-C4 alkynyl group, unsubstituted phenyl group.

In another preferred example, each R ₁ is independently a group selected from the group consisting of C1-C4 alkyl, C2-C4 alkenyl, or substituted or unsubstituted phenyl.

In another preferred example, each of the R _1s is independently a group selected from the group consisting of methyl, vinyl, and phenyl.

In another preferred example, each group is a specific group described in each compound of the embodiment.

The second aspect of the present invention provides a method for preparing the organosiloxane as described in the first aspect of the present invention, wherein the organosiloxane is hydrolyzed and polymerized with the organosilicon monomer shown in the following formula II Prepared by:

Wherein, R is _a group selected from the group consisting of:

(a) H;

(b) substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein the substitution means that one or more hydrogen atoms on the group are replaced by a substituent selected from the following group: Halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1 to 3 hydrogen atoms on the benzene ring substituted by substituents selected from the group below: Halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; said substitution means that one or more hydrogen atoms on the group are substituted by a substituent selected from the following group: halogen, C1～C4 alkyl, C1～C4 haloalkane Base, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted phenyl;

R ₂ and R ₃ are each independently a group selected from the group consisting of C1-C4 alkoxy and halogen.

In another preferred example, R ₂ , R ₃ , and R ₄ are each independently a group selected from the group consisting of C1-C2 alkoxy and halogen.

In another preferred example, the R ₁ is a group selected from the group consisting of methyl, vinyl, phenyl;

In another preferred example, said polymerization is homopolymerization or copolymerization.

In another preferred example, the copolymerization is a hydrolytic copolymerization of monomers of formula II and bis-alkoxysiloxane.

In another preferred example, the alkoxy groups in the bisalkoxysiloxane are independently substituted or unsubstituted C1-C10 alkoxy groups, wherein substitution refers to one or more hydrogen atoms on the group Substituted by a substituent selected from the following group: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or 1-3 hydrogen atoms on the benzene ring are selected from Phenyl substituted by the following substituents: halogen, C1-C4 alkyl.

In another preferred example, the two alkoxy groups in the bisalkoxysiloxane are the same or different.

In another preferred example, the hydrolytic polymerization includes the step of: in the presence of an acid catalyst, hydrolyzing the organosilicon monomer shown in formula II and optional bis-alkoxysiloxane to obtain the The organosiloxane described in the first aspect.

In another preferred example, the hydrolytic polymerization is carried out in the presence of water.

In another preferred example, when the hydrolysis polymerization is homopolymerization, the molar ratio of the acid catalyst to the monomer of formula II used in the hydrolysis polymerization is 5-10:0.8-1.2.

In another preferred example, when the hydrolysis polymerization is homopolymerization, in the hydrolysis polymerization, the molar ratio of water, acidic catalyst and formula II monomer used is 50-100:5-10:0.8- 1.2.

In another preferred example, when the hydrolytic polymerization is copolymerization, the molar ratio of the acidic catalyst used to (formula II monomer + bisalkoxysiloxane) in the hydrolytic polymerization is 5-10 :0.8-1.2.

In another preferred example, when the hydrolysis polymerization is copolymerization, in the hydrolysis polymerization, the molar ratio of water, acid catalyst and (formula II monomer + bisalkoxysiloxane) used is 50 ~100:5~10:0.8-1.2.

In another preferred example, when the hydrolytic polymerization is copolymerization, the molar ratio of the monomer of formula II to bisalkoxysiloxane used in the hydrolytic polymerization is 0.5-2:0.8-1.2.

In another preferred embodiment, the acid catalyst is selected from the group consisting of hydrochloric acid, sulfuric acid, acetic acid, formic acid, or a combination thereof; preferably, the acid catalyst is selected from the group consisting of acetic acid, formic acid, or a combination thereof .

In another preference, the hydrolytic polymerization has one or more conditions selected from the following group:

carried out in a solvent selected from the group consisting of benzene, toluene, xylene, or combinations thereof;

The hydrolytic polymerization is carried out at 10-100°C; preferably at room temperature-100°C;

The reaction time of the hydrolysis polymerization is 5-48 hours.

The third aspect of the present invention provides a kind of organosilicon monomer as shown in formula II:

Wherein, R is _a group selected from the group consisting of:

(a) H;

(b) substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein the substitution means that one or more hydrogen atoms on the group are replaced by a substituent selected from the following group: Halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1 to 3 hydrogen atoms on the benzene ring substituted by substituents selected from the group below: Halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; said substitution means that one or more hydrogen atoms on the group are substituted by a substituent selected from the following group: halogen, C1～C4 alkyl, C1～C4 haloalkane Base, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted phenyl;

R ₂ and R ₃ are each independently a group selected from the group consisting of C1-C4 alkoxy and halogen.

In another preferred example, R ₂ , R ₃ , and R ₄ are each independently a group selected from the group consisting of C1-C2 alkoxy and halogen.

A fourth aspect of the present invention provides a method for preparing monomers as described in the third aspect of the present invention, said method comprising the steps of:

In an inert solvent (such as an ether solvent), use a halogenated benzocyclobutene and Reaction, obtains the organosilicon monomer shown in formula II;

Wherein, X is a halogen, preferably selected from the following group: Cl, Br;

R ₁ is a group selected from the group consisting of:

(a) H;

(b) substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein the substitution means that one or more hydrogen atoms on the group are replaced by a substituent selected from the following group: Halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1 to 3 hydrogen atoms on the benzene ring substituted by substituents selected from the group below: Halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; said substitution means that one or more hydrogen atoms on the group are substituted by a substituent selected from the following group: halogen, C1～C4 alkyl, C1～C4 haloalkane Base, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted phenyl;

R ₂ , R ₃ , and R ₄ are each independently a group selected from the group consisting of C1-C4 alkoxy and halogen.

In another preferred example, R ₂ , R ₃ , and R ₄ are each independently a group selected from the group consisting of C1-C2 alkoxy and halogen.

In another preferred example, the ether solvent is selected from the group consisting of tetrahydrofuran, methyl tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, cyclohexyl methyl ether, cyclopentyl methyl ether, or its combination.

In another preferred example, the inert solvent is a mixture of tetrahydrofuran and toluene.

In another preferred example, the inert solvent is tetrahydrofuran and toluene; the preferred ratio is a mixture of tetrahydrofuran:toluene=1-10:10 (weight ratio or volume ratio).

In another preferred embodiment, the reaction is carried out in the presence of a magnesium catalyst; preferably, the magnesium catalyst is magnesium chips.

In another preferred example, the selected from the group consisting of methyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, methyltrichlorosilane, vinyltrichlorosilane, or combinations thereof.

In another preferred example, the reaction includes: adding and magnesium catalyst, then slowly drop the organic solvent solution of halogenated benzocyclobutene, preferably, the organic solvent is a mixed solution of tetrahydrofuran and toluene (preferably tetrahydrofuran and toluene volume ratio 0.2-5:1, relatively Optimally 0.5-3:1).

In another preferred embodiment, the reaction is carried out at 10-50°C; preferably at room temperature-50°C.

In another preferred example, the reaction time is 5-10 hours.

In another preferred example, after the reaction is finished, the solvent is removed under normal pressure, and then distilled under reduced pressure to obtain the organosilicon monomer.

In another preference, in the reaction, the halogenated benzocyclobutene, The molar ratio to the magnesium catalyst is 1:1-3:1-3; preferably 1:1.5-2.5:1.8-2.2.

A fifth aspect of the present invention provides a curing method, the method comprising the step of: polymerizing the organosiloxane described in the first aspect of the present invention to form a cured product.

In another preferred embodiment, the polymerization is polymerized and cured by heating (ie heat curing).

In another preferred example, the heating and curing temperature is 230-270°C, preferably 240-260°C.

In another preferred example, the heat curing includes: pre-curing at 170-190°C, and then curing at 230-270°C.

In another preferred example, the heat curing includes: performing pre-curing at 170-190° C., and then raising the temperature to 230-270° C. at a rate of 45-55° C./h for curing.

In another preferred example, the heat curing further includes: before the pre-curing, slowly heating and/or mechanically vibrating the organosiloxane to remove air bubbles and form a dense liquid; preferably, the The temperature rise mentioned above is from room temperature to 140-160°C.

In another preferred example, the pre-curing time is 4-6 hours.

In another preferred example, the curing time is 4-6 hours.

The sixth aspect of the present invention provides a cured product prepared by the method as described in the fifth aspect of the present invention.

In another preferred example, the 5% thermal weight loss temperature of the cured product in nitrogen is 470-530°C.

In another preferred example, the weight residue of the cured product at 1000° C. in nitrogen is ≥60%, preferably ≥65%, more preferably ≥70%, most preferably 73-77%.

In another preferred example, the dielectric constant of the cured product is 2.6-3.0 (in the range of 1-30 MHz), preferably 2.7-2.9.

The seventh aspect of the present invention provides a product containing the organosiloxane of formula I as described in the first aspect of the present invention, the organosilicon monomer of formula II as described in the third aspect of the present invention, or The cured product as described in the sixth aspect of the present invention; or

The article is prepared with the organosiloxane of formula I as described in the first aspect of the present invention, the organosilicon monomer of formula II as described in the third aspect of the present invention, or the cured product as described in the sixth aspect of the present invention of.

In another preferred example, the product is a low dielectric constant material or an insulating material covered with a metal wire.

In another preferred example, the article is a polymer sheet or film.

In another preferred embodiment, the product includes: a substrate, and a film containing the cured product according to the sixth aspect of the present invention coated on the substrate.

In another preferred example, the product is prepared by the following method: molding with the organosiloxane of formula I according to the first aspect of the present invention to obtain a preform, and then the preform Carry out heating and curing to obtain the article.

In another preferred example, the molding is performed by a molding process selected from the group consisting of heating and pressing, solution spin coating, or solution drop coating.

In another preferred example, the solution spin coating or solution drop coating includes the steps of: dissolving the organosiloxane of formula I as described in the first aspect of the present invention in an organic solvent to form a solution, and then performing spin coating or drop coating Coating; Preferably, the solvent is selected from the group consisting of: the organic solvent is toluene, xylene, trimethylbenzene, diphenyl ether, cyclohexanone, chloroform, acetone, N,N-dimethyl Formamide, N,N-dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, or combinations thereof.

In another preferred example, the degree of polymerization (ie n) of the organosiloxane of formula I=2-20.

The eighth aspect of the present invention provides a crosslinking agent containing the organosiloxane of formula I as described in the first aspect of the present invention.

In another preferred example, the cross-linking agent is a high-temperature vulcanized silicone rubber cross-linking agent (which can be directly added to the silicone resin).

The ninth aspect of the present invention provides a cross-linked silicone rubber, the silicone rubber is a high-temperature vulcanized silicone rubber, and the silicone rubber contains the compound of formula I as described in the first aspect of the present invention.

It should be understood that within the scope of the present invention, the above-mentioned technical features of the present invention and the technical features specifically described in the following (such as embodiments) can be combined with each other to form new or preferred technical solutions. Due to space limitations, we will not repeat them here.

Detailed ways

The present invention aims to provide a method for producing a direct heat-curable organosiloxane containing benzocyclobutene groups. Cross-linking polymerization can occur by heating. The cross-linked product has good electrical properties and heat resistance, and the preparation method is simple. It is suitable for the electrical and electronic industry as insulating coatings and packaging materials for electronic components, or as high-temperature silicon sulfide. Crosslinking agent for rubber.

the term

As used herein, the term "siloxane" or "organosiloxane" refers to a polymer containing Si—O—Si bonds forming the main chain structure. It is customarily called silicone or polysiloxane, which can be a linear, cyclic or cross-linked polymer. In the present invention, a preferred organosiloxane has the formula In the structure shown, each R is independently an alkyl group, an alkenyl group or an aryl group.

The terms "organosiloxane of formula I", "polymer of formula I" or "organosiloxane of the present invention" are used interchangeably and refer to the organosiloxane of formula I.

The term "benzocyclobutene substituted" or "substituted by benzocyclobutene", "having a benzocyclobutenyl group" or "having a benzocyclobutene substituent" refers to the original The part connected to the alkyl, alkenyl or aryl group (that is, the part originally R) is substituted by benzocyclobutenyl; wherein, the benzocyclobutenyl is on the benzene ring of benzocyclobutene Loss of a hydrogen atom forms a group such as or similar groups.

The term "halogen" refers to fluorine, chlorine, bromine, iodine.

The term "halo" refers to the replacement of one or more hydrogen atoms on a group with a halogen.

The term "C1-C6 alkyl" refers to a straight-chain or branched-chain alkyl group with 1-6 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, or Similar groups.

The term "C2-C6 alkenyl" refers to a straight-chain or branched alkenyl group having 2-6 carbon atoms, such as vinyl, propenyl, allyl, 1-butenyl, 2-butenyl, or the like group.

The term "C2-C6 alkenyl" refers to a straight-chain or branched alkynyl group having 2-6 carbon atoms, such as ethynyl, propynyl, allyl, 1-butynyl, 2-butynyl, or Similar groups.

The term "C1-C4 alkoxy" refers to a substituent formed by connecting a straight-chain or branched-chain alkyl group with 1 to 4 carbon atoms and oxygen, such as methoxy, ethoxy, n-propoxy, isopropyl oxy, n-butoxy, tert-butoxy, or similar groups.

Organosiloxanes containing benzocyclobutene

It is known that existing silicone resins need to form a cross-linking system in order to be more widely used. And because the benzocyclobutene unit can open the ring of the cyclobutene unit after being heated, thereby forming a high molecular weight system polymer, it is suitable to be introduced into the silicone resin to form a crosslinking system.

However, in the prior art, the method of coupling the benzocyclobutene unit with the polymerized organosiloxane has been adopted. Organosiloxanes containing benzocyclobutene structural units reported in the art all require Pt-catalyzed HECK coupling reaction to introduce benzocyclobutene structural units into organosiloxanes. The disadvantage of this is that it is difficult to completely remove the Pt catalyst after the reaction is over, and the Pt catalyst is a noble metal, resulting in very high cost of the existing organosiloxane containing benzocyclobutene.

In the present invention, a relatively simple process is adopted to react bromobenzocyclobutene with metal magnesium, and then react the obtained benzocyclobutene Grignard reagent with organosiloxane to obtain siloxane and benzene A monomer in which cyclobutene units are directly linked. The monomer is hydrolyzed and polymerized to obtain a silicone resin whose main chain is siloxane and whose side chain is benzocyclobutene.

Specifically, the organosiloxane resin provided by the present invention has a siloxane main chain and a benzocyclobutene substituent on the silicon atom of the siloxane main chain. Wherein, the benzocyclobutene substituent is directly connected to the silicon atom on the siloxane main chain (that is, connected through Si-Ph bond).

The type of the siloxane main chain is not particularly limited, and in another preferred example, the siloxane main chain has a shape such as structure; wherein, x=2～200;

Each R is independently substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, or substituted or unsubstituted phenyl; the substitution refers to one or more hydrogens on the group Atoms are substituted by substituents selected from the following group: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or 1-3 hydrogen atoms on the benzene ring are selected Phenyl substituted by substituents from the following group: halogen, C1-C4 alkyl;

And the benzocyclobutene substitution means that one or more R groups on the main chain are replaced by benzocyclobutene substituents.

Each of the siloxane main chains can optionally have or not have a benzocyclobutene substituent, and the silicon atoms on each siloxane main chain can be substituted in any form, such as in a certain segment There are benzocyclobutene substituents on all of them, and no benzocyclobutene substituents on other segments, thus forming a block copolymer; or there is a benzocyclobutene at a position separated by a silicon atom Substituents. The substitution mode of the benzocyclobutene substituent can be adjusted by means of homopolymerization or copolymerization of monomers, the respective dosages of different monomers, or block copolymerization.

In another preferred example, ≥30% of the silicon atoms on the siloxane main chain have the benzocyclobutene substituent; preferably, ≥50% of the silicon atoms on the siloxane main chain have The benzocyclobutene substituent; more preferably, ≥70% of the silicon atoms on the siloxane main chain have the benzocyclobutene substituent; most preferably, the siloxane main chain Each silicon atom of has said benzocyclobutene substituent.

In another preferred example, the refractive index of the organosiloxane resin is 1.5-1.6.

In another preferred example, the main chain of the siloxane is linear or branched, preferably linear.

In a preferred embodiment of the present invention, the organosiloxane has the structure shown in the following formula I:

Wherein, n=2～100, preferably, n=2～50, more preferably n=2～20;

Each R ₁ is independently a group selected from the following group: substituted or unsubstituted C1～C4 alkyl, substituted or unsubstituted C2～C4 alkenyl, or substituted or unsubstituted phenyl; wherein, the substituted It means that one or more hydrogen atoms on the group are replaced by substituents selected from the following groups: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, phenyl; wherein, the The phenyl is unsubstituted or 1 to 3 hydrogen atoms on the benzene ring are substituted by a substituent selected from the following group: halogen, _C1 to C4 alkyl; preferably, each of the R1 are independently a group selected from the group consisting of methyl, vinyl, phenyl.

The organosiloxane is prepared by hydrolytic polymerization of an organosilicon monomer represented by the following formula II:

Wherein, R ₁ is a group selected from the following group: substituted or unsubstituted C1～C6 alkyl, substituted or unsubstituted C2～C6 alkenyl, or substituted or unsubstituted phenyl; wherein, the substitution means One or more hydrogen atoms on the group are substituted by a substituent selected from the following group: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, phenyl; wherein, the The phenyl is unsubstituted or 1 to 3 hydrogen atoms on the benzene ring are substituted by a substituent selected from the following group: halogen, C1 to C4 alkyl; preferably, the R ₁ is selected from Groups from the following group: methyl, vinyl, phenyl;

R ₂ and R ₃ are each independently a group selected from the group consisting of C1-C4 alkoxy and halogen.

Said polymerization can be a homopolymerization reaction with the monomer of formula II, or a copolymerization reaction of the monomer of formula II with other siloxane monomers. In another preferred example, the copolymerization is a hydrolytic copolymerization reaction of a monomer of formula II and bisalkoxysiloxane.

In another preferred example, the hydrolytic polymerization includes the step of: in the presence of water and an acid catalyst, hydrolyzing the organosilicon monomer shown in formula II and optional bis-alkoxysiloxane to obtain the described organosiloxanes. In another preferred example, when the hydrolytic polymerization is homopolymerization, the molar ratio of water, acidic catalyst and monomer of formula II used in the hydrolytic polymerization is 50-100:5-10:1.

In the hydrolytic polymerization reaction, since the cyclobutene structural unit is very easy to ring-open, it is necessary to select a suitable acid catalyst to obtain a higher yield. In the present invention, the acid catalyst is preferably selected from the group consisting of hydrochloric acid, sulfuric acid, acetic acid, formic acid, or a combination thereof; more preferably, the acid catalyst is selected from the group consisting of acetic acid, formic acid, or a combination thereof.

The solvent of the hydrolytic polymerization reaction is not particularly limited, and it is preferably carried out in a solvent selected from the following group: benzene, toluene, xylene, or a combination thereof.

The temperature of the hydrolytic polymerization is not particularly limited, and it is preferably carried out at 10-100°C; preferably at room temperature (10-40°C)-100°C.

The hydrolysis polymerization reaction time is not particularly limited, and the end point of the reaction can be determined by a common method in the art (such as thin layer chromatography, etc.). Preferably, the reaction time is 5-20 hours.

All raw materials used in the present invention are commercially available, and do not need any transition metal catalysts during coupling or polymerization.

Silicone monomer containing benzocyclobutene

The present invention also provides a kind of organosilicon monomer as shown in formula II:

Wherein, R ₁ is a group selected from the following group: substituted or unsubstituted C1～C6 alkyl, substituted or unsubstituted C2～C6 alkenyl, or substituted or unsubstituted phenyl; wherein, the substitution means One or more hydrogen atoms on the group are substituted by a substituent selected from the following group: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, phenyl; wherein, the The phenyl is unsubstituted or 1 to 3 hydrogen atoms on the benzene ring are substituted by a substituent selected from the following group: halogen, C1 to C4 alkyl; preferably, the R ₁ is selected from Groups from the following group: methyl, vinyl, phenyl;

R ₂ and R ₃ are each independently a group selected from the group consisting of C1-C4 alkoxy and halogen.

Described monomer can be prepared with following method:

In an inert solvent, use a halogenated benzocyclobutene with Reaction, obtains the organosilicon monomer shown in formula II;

Wherein, X is a halogen, preferably selected from the following group: Cl, Br;

R ₁ is a group selected from the group consisting of substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, or substituted or unsubstituted phenyl; wherein the substitution refers to the group One or more hydrogen atoms on is substituted by a substituent selected from the following group: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, phenyl; wherein, the benzene The phenyl group is unsubstituted or 1 to 3 hydrogen atoms on the benzene ring are substituted by a substituent selected from the following group: halogen, C1 to C4 alkyl; preferably, the R ₁ is selected from the following Group of groups: methyl, vinyl, phenyl;

R ₂ , R ₃ , and R ₄ are each independently a group selected from the group consisting of C1-C4 alkoxy and halogen.

The ether solvent is not particularly limited, and is preferably selected from the group consisting of tetrahydrofuran, methyl tetrahydrofuran, diethyl ether, dioxane, ethylene glycol dimethyl ether, cyclohexyl methyl ether, cyclopentyl methyl ether or its combination.

In another preferred embodiment of the present invention, in order to facilitate post-treatment, in particular, a mixture of tetrahydrofuran and toluene is used. The ratio of the mixture is tetrahydrofuran:toluene=10:1~10 (weight ratio or volume ratio).

Preferably, the reaction is carried out in the presence of a magnesium catalyst, reacting with a halogenated benzocyclobutene (preferably bromobenzocyclobutene) and a magnesium catalyst, after generating the Grignard reagent, and reaction. Preferably, the magnesium catalyst is magnesium chips.

In another preferred example, the selected from the group consisting of methyltriethoxysilane, vinyltrimethoxysilane, or combinations thereof.

In another preferred example, the selected from the group consisting of methyltrichlorosilane, vinyltrichlorosilane, or combinations thereof.

In another preferred example, the reaction includes: adding and magnesium catalyst, and then slowly drop the organic solvent solution of halogenated benzocyclobutene, preferably, the organic solvent is a mixed solution of tetrahydrofuran and toluene (2:1, volume ratio).

In another preferred embodiment, the reaction is carried out at 10-50°C; preferably at room temperature-50°C.

In another preferred example, the reaction time is 5-10 hours.

In another preferred example, after the reaction is finished, the solvent is removed under normal pressure, and then distilled under reduced pressure to obtain the organosilicon monomer.

Application of silicone resin

The present invention also provides the use of an organosiloxane as shown in formula I. The organosiloxane can be used in the electrical and electronic industry as an insulating coating and packaging material for electronic components, or for preparing Low dielectric constant materials or metal wires are covered with insulating materials, or used as a crosslinking agent for high temperature vulcanized silicone rubber.

One application of the organosiloxane of the present invention is to prepare a cured product of the organosiloxane structure, and the cured product is prepared by heating and curing the organosiloxane of formula I as described.

Wherein, the heating and curing conditions are not particularly limited, and can be adjusted according to the specific type of organosiloxane used, and the performance requirements of the cured product. In a preferred embodiment of the present invention, the heating and curing temperature is 230-270°C, preferably 240-260°C.

The heating curing may also optionally include a pre-curing step, that is, curing for a period of time at a temperature lower than the heating curing temperature. In another preferred example, the heat curing includes: pre-curing at 170-190°C, and then curing at 230-270°C.

The heating and curing can be carried out under the condition of temperature programming. In another preferred example, the heating and curing include: pre-curing at 170-190°C, and then heating at a rate of 45-55°C/h The temperature is raised to 230-270°C and cured.

The pre-curing time and the curing time are not particularly limited. In a preferred embodiment of the present invention, the pre-curing time is 4-6 hours, and the curing time is 4-6 hours.

Preferably, when preparing the cured product, using an organosiloxane of formula I with a shorter chain length can better adjust a series of properties of the product such as hardness, glass transition temperature, etc., and the processing is more convenient . In the preferred silicone resin of formula I used to prepare the cured product, the degree of polymerization (ie n)=2-20.

The cured product has good thermal properties. In a preferred example of the present invention, the 5% thermal weight loss temperature of the cured product in nitrogen is 470-530°C. In another preferred example, the weight residue of the cured product at 1000° C. in nitrogen is ≥60%, preferably ≥65%, more preferably ≥70%, most preferably 73-77%.

The cured product has good electrical properties. In another preferred example, the dielectric constant of the cured product is 2.60-3.0 (in the range of 1-30 MHz).

The silicone resin of the present invention can also be used to prepare a kind of article, and described article contains described formula I organosiloxane, formula II organosilicon monomer, or described cured product; Or described article is used prepared from the organosiloxane of the formula I, the organosilicon monomer of the formula II, or the cured product.

In another preferred example, the product is a low dielectric constant material or an insulating material covered with a metal wire.

In another preferred example, the article is a polymer sheet or film.

In another preferred embodiment, the product includes: a substrate, and a film containing the cured product coated on the substrate.

In another preferred example, the product is prepared by the following method: molding with the organosiloxane of formula I to obtain a preform, and then heating and curing the preform to obtain the described products.

In another preferred example, the molding is performed by a molding process selected from the group consisting of heating and pressing, solution spin coating, or solution drop coating. In particular, since the organosiloxane of formula I has good solubility properties, it can preferably be processed by solution spin coating or drop coating.

In another preferred embodiment, the solution spin coating or solution drop coating includes the steps of: dissolving the organosiloxane of formula I in an organic solvent to form a solution, and then performing spin coating or drop coating; preferably, Described solvent is selected from following group: described organic solvent is toluene, xylene, mesitylene, diphenyl ether, cyclohexanone, chloroform, acetone, N,N-dimethylformamide, N,N - Dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, or combinations thereof.

In another preferred example, the degree of polymerization (ie n) of the organosiloxane of formula I=2-20.

The organosiloxane of the present invention can also be used as a crosslinking agent for the preparation of high temperature vulcanized silicone rubber. When used, the organosiloxane of the present invention is directly added to the silicone resin.

Main advantage of the present invention:

(1) The preparation process of the organosilicon monomer containing benzocyclobutene provided by the present invention is simple, compared with the organosiloxane monomer containing benzocyclobutene reported in the prior art, the synthesis only uses Simple Grignard reaction can complete the preparation, and the used raw materials alkylalkoxysilane and halogenated benzocyclobutene are all commercially available raw materials, and the price is low, compared with the starting raw material diethylene used in the prior art Compared with base siloxane or hydrogen-containing silicone oil, the cost is significantly reduced, so that the synthesis cost of the final monomer is greatly reduced.

(2) The organosiloxane of the present invention can be prepared by hydrolytic polymerization. Compared with the prior art, the preparation of the prepolymer of the monomer needs to be carried out at a higher temperature. The preparation method is simple, the conditions are mild, and the reaction can be control, and the molecular weight of the obtained prepolymer (ie organosiloxane) can be effectively controlled.

(3) The organosiloxane of the present invention does not need to be prepared using noble metal catalysts such as platinum, which greatly reduces the cost of preparation.

(4) The preparation method of the present invention is simple, requires low equipment, and is suitable for industrial production.

(5) The organosiloxane provided by the present invention can be used to prepare cured products with good electrical properties, heat resistance and mechanical properties, and its thermal stability has been significantly improved.

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. For the experimental methods without specific conditions indicated in the following examples, the conventional conditions or the conditions suggested by the manufacturer are usually followed. Percentages and parts are by weight unless otherwise indicated.

The preparation of embodiment 1 methyldiethoxybenzocyclobutenylsilane

Under argon protection, magnesium chips (9.6g, 0.4mol), methyltriethoxysilane (89g, 0.5mol) and anhydrous tetrahydrofuran 60mL were added to a 500mL dry three-neck flask, and 4- Bromobenzocyclobutene (36.6g, 0.2mol) in 40mL of anhydrous tetrahydrofuran solution, after dripping and stirring at room temperature for 3.5 hours, inject 100mL of anhydrous toluene, a large amount of organic salts precipitated, filtered, and the oil pump reduced Pressure distillation: collect fractions at 98-104°C (1.5 mmHg) to obtain 32.75 g of a colorless transparent liquid with a yield of 69%.

¹ H NMR (CDCl ₃ , 400MHz): 0.38(s, 3H), 1.26～1.30(t, 6H), 3.23(s, 4H), 3.82～3.88(m, 4H), 7.11～7.13(d ,1H),7.38(s,1H),7.52～7.54(d,2H).

Carbon spectrum characterization ¹³ C NMR (CDCl ₃ , 100MHz): 3.92, 18.44, 29.96, 30.01, 58.53, 122.04, 127.82, 132.46, 132.83, 145.65, 148.27.

The preparation of embodiment 2 vinyldiethoxybenzocyclobutenylsilane

Under argon protection, magnesium chips (7.2g, 0.3mol), vinyltriethoxysilane (45g, 0.24mol), anhydrous tetrahydrofuran 60mL were added to a 500mL dry three-neck flask, and 4- Bromobenzocyclobutene (27.2g, 0.15mol) in 30mL of anhydrous tetrahydrofuran solution, after dripping, stirred at room temperature for 3.5 hours, then injected 100mL of anhydrous toluene, a large amount of organic salts precipitated, filtered, rotary evaporated to remove low boiling point solvent, and then pumped Distillation under reduced pressure: 98-104°C (1.5 mmHg) fractions were collected to obtain 23.4 g of a colorless transparent liquid with a yield of 63%.

¹ H NMR (CDCl ₃ , 400MHz): 1.25～1.29(t,6H), 3.22(d,4H), 3.84～3.89(m,4H), 5.92～6.01(m,1H), 6.13～6.21(m, 2H), 7.10～7.12(dd,1H), 7.37(s,1H), 7.52～7.54(d,2H).

Carbon spectrum characterization ¹³ C NMR (CDCl ₃ , 100MHz): 18.46, 30.02, 30.04, 58.82, 122.05, 128.40, 131.05, 132.53, 133.11, 136.75, 145.67, 148.54.

The preparation of embodiment 3 prepolymer polymethylbenzocyclobutenyl siloxane

Under argon protection, add 30 grams (0.5mol) of acetic acid, 11.8 grams (0.05mol) of the monomer methyldiethoxybenzocyclobutenylsilane obtained in Example 1 in the reaction flask, and reflux for 24 hours Afterwards, the low boiling point components were removed by rotary evaporation, and vacuum-dried at 80°C for 5 hours to obtain a quantitative light yellow viscous product. GPC characterization, number average molecular weight 1000, molecular weight distribution, 1.71.

Hydrogen spectrum characterization: ¹ H NMR (CDCl ₃ , 400MHz): 0.22～0.61(m,3H), 3.22～3.27(m,4H), 6.96～7.58(m,3H).

Carbon spectrum characterization ¹³ C NMR (CDCl ₃ , 100MHz): -0.74, 29.97, 30.01, 121.90, 127.14, 132.00, 135.42, 145.38, 148.03.

The refractive index of the obtained polymer was 1.56 at room temperature as measured by an Abbe refractometer.

Preparation of embodiment 4 prepolymer polyvinylbenzocyclobutenyl siloxane

Under argon protection, add 30 grams (0.5mol) of acetic acid, 12.42 grams (0.05mol) of monomer vinyldiethoxybenzocyclobutenylsilane obtained in Example 2 in the reaction flask, and reflux for 24 hours Afterwards, low boiling point components were removed by rotary evaporation, and vacuum-dried at 80°C for 5 hours to obtain a quantitative yellow viscous product. GPC characterization, number average molecular weight 1200, molecular weight distribution, 1.66. Proton spectrum characterization: ¹ H NMR (CDCl ₃ , 400MHz): 3.13～3.26(m, 4H), 5.84～6.25(m, 3H), 6.93～7.63(m, 3H), ¹³ C NMR(CDCl ₃ , 100MHz) : 30.00, 30.02, 121.86, 127.81, 132.56, 134.04, 135.44, 136.54, 145.48, 148.65.

The refractive index of the obtained polymer was 1.57 at room temperature as measured by an Abbe refractometer.

The preparation of embodiment 5 methylbenzocyclobutenylsiloxane and methylphenyldimethoxysilane copolymer

Under argon protection, add 6 gram (0.1mol) acetic acid, 1.18 gram (0.005mol) by the monomer methyldiethoxybenzocyclobutenylsilane that embodiment 1 obtains in reaction flask, 0.91 gram (0.005 mol) methylphenyldimethoxysilane, refluxed for 24 hours, then rotary evaporated to remove low-boiling components, and vacuum-dried at 80°C for 5 hours to obtain a quantitative yellow viscous product. GPC characterization, number average molecular weight 800, molecular weight distribution, 1.5. Proton spectrum characterization: ¹ H NMR (CDCl ₃ , 400MHz): 0.05～0.60(m,6H), 3.08～3.27(m,4H), 6.88～7.78(m,8H).

Example 6 Preparation of Methylbenzocyclobutenylsiloxane and Dimethyldiethoxysilane Copolymer Under protection of argon, add 12 grams (0.2mol) of acetic acid, 2.36 grams (0.01mol) ) monomer methyldiethoxybenzocyclobutenylsilane obtained by embodiment 1, 1.48 grams (0.01mol) dimethyldiethoxysilane, reflux reaction after 24 hours rotary evaporation removes low boiling point components , 80 ° C vacuum drying for 5 hours to obtain a quantitative yellow viscous product. GPC characterization, number average molecular weight 840, molecular weight distribution, 1.53. Proton spectrum characterization: ¹ H NMR (CDCl ₃ , 400MHz): 0.10～0.59(m,9H), 3.28～3.30(m,4H), 7.08～7.21(m,1H), 7.31～7.47(m,1H), 7.49～7.68(m,1H).

Embodiment 7 Preparation of vinylbenzocyclobutenylsiloxane and methylphenyldimethoxysilane copolymer

Under the protection of argon, add 6 gram (0.1mol) acetic acid, 1.24 gram (0.005mol) by the monomer vinyldiethoxybenzocyclobutenylsilane that embodiment 2 obtains in reaction flask, 0.91 gram (0.005 mol) methylphenyldimethoxysilane, refluxed for 24 hours, then rotary evaporated to remove low-boiling components, and vacuum-dried at 80°C for 5 hours to obtain a quantitative yellow viscous product. GPC characterization, number average molecular weight 780, molecular weight distribution, 1.45. Proton spectrum characterization: ¹ H NMR (CDCl ₃ , 400MHz): 0.07～0.62(m,3H), 3.08～3.28(m,4H), 5.73～6.37(m,3H), 6.83～7.78(m,8H).

Embodiment 8 Preparation of vinylbenzocyclobutenylsiloxane and dimethyldiethoxysilane copolymer

Under the protection of argon, add 12 grams (0.2mol) acetic acid, 2.48 grams (0.01mol) by the monomer vinyldiethoxybenzocyclobutenylsilane that embodiment 2 obtains in reaction flask, 1.48 grams (0.01 mol) dimethyldiethoxysilane, refluxed for 24 hours, then rotary evaporated to remove low-boiling components, and vacuum-dried at 80°C for 5 hours to obtain a quantitative yellow viscous product. GPC characterization, number average molecular weight 810, molecular weight distribution, 1.48. Proton spectrum characterization: ¹ H NMR (CDCl ₃ , 400MHz): 0.06～0.42(m,6H), 3.26～3.29(m,4H), 5.84～6.41(m,3H), 7.01～7.19(m,1H), 7.31～7.47(m,1H),7.48～7.67(m,1H).

The curing of embodiment 9 homopolymer and the heat resistance property of cured product

Put 1.5 g of the polymer obtained in Example 3 into a flat-bottomed schlenk tube with an inner diameter of 1 cm, raise the temperature to 250 ° C, and keep it at this temperature for 5 hours, then cool to room temperature, remove the solidified material, grind it finely, and perform TGA test. The results show that the cured product has a 5% thermal weight loss temperature of 496°C in nitrogen, and a weight residue of 75% at 1000°C.

Dielectric properties after embodiment 10 homopolymer cured

Place 1.5 g of the polymer obtained in Example 3 in a flat-bottomed schlenk tube with an inner diameter of 1 cm, vacuumize and slowly heat up to 150 ° C under mechanical vibration to remove air bubbles to form a dense liquid, heat up to 180 ° C, and keep at this temperature for 5 hours to make it pre-cured. After cooling to room temperature, move it to a quartz tube furnace and raise the temperature to 250°C at a rate of 50°C/h, and keep it at this temperature for 5 hours, take it out and polish it into a disc, and measure its dielectric constant. The results show that within the frequency range of 1MHz to 30MHz , and its dielectric constant is between 2.75 and 2.85.

The curing of embodiment 11 copolymer and the heat resistance property of cured product

Put 1.5 g of the polymer obtained in Example 5 into a flat-bottomed schlenk tube with an inner diameter of 1 cm, raise the temperature to 250 ° C, and keep it at this temperature for 5 hours, then cool to room temperature, remove the solidified material, grind it finely, and perform a TGA test. The results showed that the cured product had a 5% thermal weight loss temperature of 485°C in nitrogen, and a weight residue of 73% at 1000°C.

Dielectric properties after embodiment 12 copolymer is solidified

Place 1.5 g of the polymer obtained in Example 3 in a flat-bottomed schlenk tube with an inner diameter of 1 cm, vacuumize and slowly heat up to 150 ° C under mechanical vibration to remove air bubbles to form a dense liquid, heat up to 180 ° C, and keep at this temperature for 5 hours to make it pre-cured. After cooling to room temperature, move it to a quartz tube furnace and raise the temperature to 250°C at a rate of 50°C/h, and keep it at this temperature for 5 hours, take it out and polish it into a disc, and measure its dielectric constant. The results show that within the frequency range of 1MHz to 30MHz , and its dielectric constant is between 2.72 and 2.83.

All documents mentioned in this application are incorporated by reference in this application as if each were individually incorporated by reference. In addition, it should be understood that after reading the above teaching content of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Claims (10)

1. An organosiloxane characterized in that the organosiloxane has a siloxane backbone and has benzocyclobutene groups attached directly to silicon atoms of the siloxane backbone.

2. The organosiloxane of claim 1 wherein the siloxane backbone has the structure of formula a;

Wherein,

x is a positive integer not less than 2 (preferably 2 to 200);

Each R is independently selected from the group consisting of:

(a)H；

(b) Substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein said substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1-3 hydrogen atoms on the phenyl ring substituted by substituents selected from the group consisting of: halogen, C1-C4 alkyl;

(c) substituted or unsubstituted phenyl; the substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, alkyl of C1-C4, halogenated alkyl of C1-C4, alkenyl of C2-C4, alkynyl of C2-C4 and unsubstituted phenyl;

(d) Benzocyclobutene radical;

And at least one R is benzocyclobutene.

3. The organosiloxane of claim 1 wherein the organosiloxane has the structure shown in formula I:

Wherein n is a positive integer not less than 2 (preferably n is 2 to 100, more preferably n is 2 to 50, and most preferably n is 2 to 20);

Each R1 is independently selected from the group consisting of:

(a)H；

(b) Substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein said substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1-3 hydrogen atoms on the phenyl ring substituted by substituents selected from the group consisting of: halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; the substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, alkyl of C1-C4, halogenated alkyl of C1-C4, alkenyl of C2-C4, alkynyl of C2-C4 and unsubstituted phenyl.

4. The method of preparing an organosiloxane as in claim 1 wherein the organosiloxane is prepared by hydrolytic polymerization of an organosilicon monomer of the formula II:

Wherein R1 is a group selected from:

(a)H；

(b) Substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein said substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1-3 hydrogen atoms on the phenyl ring substituted by substituents selected from the group consisting of: halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; the substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, alkyl of C1-C4, halogenated alkyl of C1-C4, alkenyl of C2-C4, alkynyl of C2-C4 and unsubstituted phenyl;

R2, R3 are each independently a group selected from: alkoxy of C1-C4 and halogen.

5. The method of claim 4, wherein said hydrolytic polymerization comprises the steps of: hydrolyzing with an organosilicon monomer of formula II and optionally a bis-alkoxy siloxane in the presence of an acid catalyst to obtain the organosiloxane of claim 1;

Preferably, the hydrolytic polymerization reaction also has one or more of the following characteristics:

The acid catalyst is selected from the group consisting of: hydrochloric acid, sulfuric acid, acetic acid, formic acid, or a combination thereof; preferably, the acid catalyst is selected from the group consisting of: acetic acid, formic acid, or a combination thereof;

The hydrolytic polymerization is carried out in a solvent selected from the group consisting of: benzene, toluene, xylene, or combinations thereof;

The hydrolytic polymerization is carried out at 10-100 ℃; preferably at room temperature to 100 ℃;

The hydrolytic polymerization reaction time is 5-48 h.

6. An organosilicon monomer of formula II:

Wherein R1 is a group selected from:

(a)H；

(b) Substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein said substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1-3 hydrogen atoms on the phenyl ring substituted by substituents selected from the group consisting of: halogen, C1-C4 alkyl;

(c) Substituted or unsubstituted phenyl; the substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, alkyl of C1-C4, halogenated alkyl of C1-C4, alkenyl of C2-C4, alkynyl of C2-C4 and unsubstituted phenyl;

r2, R3 are each independently a group selected from: alkoxy of C1-C4 and halogen.

7. The method of preparing the monomer of claim 6, comprising the steps of:

Reacting halogenated benzocyclobutene in an inert solvent (such as an ether solvent) to obtain an organic silicon monomer shown in a formula II;

Wherein X is halogen, preferably selected from the group consisting of: cl, Br;

R1 is a group selected from:

(a)H；

(b) Substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C2-C6 alkenyl, wherein said substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, C1-C4 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, unsubstituted or phenyl with 1-3 hydrogen atoms on the phenyl ring substituted by substituents selected from the group consisting of: halogen, C1-C4 alkyl;

(c) substituted or unsubstituted phenyl; the substitution means that one or more hydrogen atoms on the group are substituted with a substituent selected from the group consisting of: halogen, alkyl of C1-C4, halogenated alkyl of C1-C4, alkenyl of C2-C4, alkynyl of C2-C4 and unsubstituted phenyl;

R2, R3, R4 are each independently a group selected from: C1-C4 alkoxy and halogen.

8. A method of curing, comprising the steps of: polymerizing the organosiloxane of claim 1 to form a cured product.

9. A cured product produced by the method according to claim 9.

10. An article comprising the organosiloxane of formula I of claim 1, the silicone monomer of formula II of claim 7, or the cured product of claim 10; or

The article is prepared with the organosiloxane of formula I as described in claim 1, the silicone monomer of formula II as described in claim 7, or the cured product as described in claim 10;

Preferably, the article is selected from the group consisting of: a cross-linking agent, or a cross-linked silicone rubber.