阅读说明：本技术 一种led粘接用含磷硅烷共聚物及其制备方法 (Phosphorus-containing silane copolymer for LED bonding and preparation method thereof ) 是由 黄天次 王成 何苗 冯琼华 肖俊平 于 2021-08-27 设计创作，主要内容包括：本发明公开一种LED粘接用含磷硅烷共聚物的制备方法,其包括以下步骤：将一种或两种以上的烷氧基硅烷、含磷硅烷、溶剂和负载型催化剂依次加入反应瓶中,室温持续搅拌均匀得到硅烷反应液；将超纯水加入另一份溶剂中,混合均匀得到混合液,将所述混合液在45-55℃下缓慢滴加到硅烷反应液中；滴加完毕后继续保温反应2-4h,当检测体系中水分含量小于2000ppm时反应完全；蒸馏除去反应液中的溶剂,并滤除固体催化剂,得到所述的LED粘接用含磷硅烷共聚物。本发明通过分子结构设计,在有机硅聚合物中引入磷元素,赋予其优异的热稳定性、阻燃性和抗静电性,有效改善阻燃剂与基体的相容性,减少阻燃剂的用量,具有更广阔的应用前景。(The invention discloses a preparation method of a phosphorus-containing silane copolymer for LED bonding, which comprises the following steps: sequentially adding one or more of alkoxysilane, phosphorus-containing silane, solvent and supported catalyst into a reaction bottle, and continuously stirring uniformly at room temperature to obtain a silane reaction solution; adding ultrapure water into the other part of solvent, uniformly mixing to obtain a mixed solution, and slowly dropwise adding the mixed solution into the silane reaction solution at the temperature of 45-55 ℃; after the dropwise addition is finished, the reaction is continued for 2 to 4 hours under the condition of heat preservation, and the reaction is complete when the water content in the detection system is less than 2000 ppm; and distilling to remove the solvent in the reaction liquid, and filtering out the solid catalyst to obtain the phosphorus-containing silane copolymer for LED bonding. According to the invention, through molecular structure design, phosphorus element is introduced into the organic silicon polymer, so that the organic silicon polymer is endowed with excellent thermal stability, flame retardance and antistatic property, the compatibility of the flame retardant and a matrix is effectively improved, the dosage of the flame retardant is reduced, and the organic silicon polymer flame retardant has a wider application prospect.)

1. A phosphorus-containing silane copolymer for LED bonding, which is characterized in that: the structural formula is shown as formula I:

in the above formula, Q is methoxy or ethoxy; m is a carbon chain number of C₁～C₄An alkoxy group of (a); r₃、R₅、R₇、R₉Each represents a methyl group or a carbon chain number C₁～C₄An alkoxy group of (a); r₁Represents a phosphorus-containing organic group; r₂、R₄、R₆、R₈Respectively represent vinyl, allyl, glycidoxyalkyl, methacryloxyalkyl, acryloxypropyl, mercaptopropyl, the number of carbon chains is C₁～C₈Alkyl and carbon chain number of C₁～C₄One of the alkoxy groups of (a); a is 1 or 2; b. c, d and e are positive integers of 0-8.

2. The phosphorus-containing silane copolymer for LED bonding according to claim 1, wherein: the R is₁The structural formula of the organic group containing phosphorus is shown as formula II-formula IV:

3. the phosphorus-containing silane copolymer for LED bonding according to claim 1, wherein: in the formula I, the values of a, b, c, d and e satisfy: a + b + c + d + e is more than or equal to 6 and less than or equal to 22, and b + c + d + e is more than or equal to 5 a.

4. The method for preparing the phosphorus-containing silane copolymer for bonding the LED according to claim 1 or 2, wherein: which comprises the following steps:

1) sequentially adding one or more of alkoxysilane, phosphorus-containing silane, solvent and supported catalyst into a three-neck flask with a reflux condenser, and continuously and uniformly stirring at room temperature to obtain a silane reaction solution; the molar ratio of all the added alkoxy silane to the added phosphorus-containing silane is 5-10: 1;

2) adding ultrapure water into the other part of solvent, uniformly mixing to obtain a mixed solution, and slowly dropwise adding the mixed solution into the silane reaction solution obtained in the step 1) at the temperature of 45-55 ℃; after the dropwise addition is finished, the reaction is continued for 2 to 4 hours under the condition of heat preservation, and the reaction is complete when the water content in the detection system is less than 2000 ppm;

3) distilling to remove the solvent in the reaction liquid obtained in the step 2), and filtering out the solid catalyst to obtain the phosphorus-containing silane copolymer for LED bonding.

5. The method for preparing the phosphorus-containing silane copolymer for LED bonding according to claim 4, wherein: the molecular formula of the alkoxy silane is shown as a formula V:

Y-Si(R₁₀)_n(OR₁₁)_(3-n)formula V;

when formula V represents vinylsilane, Y is vinyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents allylsilane, Y is allyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents glycidoxyalkylsilane, Y is glycidoxypropyl; r₁₀Is methyl; r₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents a methacryloxypropyl radical, Y is methacryloxypropyl radical; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents an acryloxysilane, Y is acryloxypropyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents mercaptopropyl silane, Y is mercaptopropyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when formula V represents an alkylalkoxysilane, Y is one of the following: methyl, ethyl, propyl, n-octyl, cyclohexyl, isobutyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents an orthosilicate silane, Y is methoxy, ethoxy, or propoxy; r₁₀Is methyl, R₁₁Is C₁～C₄Alkyl of (a), and the Y group and R₁₁Wherein the carbon number is the same, and n is 0.

6. The method for preparing the phosphorus-containing silane copolymer for LED bonding according to claim 3, wherein: the phosphorus-containing silane is one of four silanes of the following formulas VI to IX:

7. the method for preparing the phosphorus-containing silane copolymer for LED bonding according to claim 5, wherein: when the alkoxysilane is a vinyl silane, the vinyl silane is one of the following: vinyltrimethoxysilane, vinyltriethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane;

when the alkoxy silane is allyl silane, the allyl silane is one of the following: allyltrimethoxysilane, allyltriethoxysilane, allylmethyldimethoxysilane, allylmethyldiethoxysilane;

when the alkoxysilane is a glycidoxyalkylsilane, the glycidoxyalkylsilane is one of the following: 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane;

when the alkoxysilane is a methacryloxyalkylsilane, the methacryloxyalkylsilane is one of the following: methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropylmethyldiethoxysilane;

when the alkoxysilane is an acryloxysilane, the acryloxysilane is one of: acryloxypropyltrimethoxysilane, acryloxypropyltriethoxysilane, acryloxypropylmethyldimethoxysilane, acryloxypropylmethyldiethoxysilane;

when the alkoxy silane is mercaptopropyl silane, the mercaptopropyl silane is one of the following: mercaptopropyl trimethoxysilane, mercaptopropyl triethoxysilane, mercaptopropyl methyldimethoxysilane, or mercaptopropyl methyldiethoxysilane;

when the alkoxysilane is an alkylalkoxysilane, the alkylalkoxysilane is one of the following: methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propylmethyldimethoxysilane, propylmethyldiethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, n-octylmethyldimethoxysilane, n-octylmethyldiethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, isobutylmethyldimethoxysilane, isobutylmethyldiethoxysilane;

when the alkoxy silane is orthosilicate ester silane, the orthosilicate ester silane is one of the following: methyl orthosilicate, ethyl orthosilicate and propyl orthosilicate.

8. The method for preparing the phosphorus-containing silane copolymer for LED bonding according to claim 4, wherein: the solvent is one or a mixture of more than two of the following solvents: methanol, ethanol, isopropanol, propanol, tetrahydrofuran, acetone and butanone.

9. The method for preparing the phosphorus-containing silane copolymer for LED bonding according to claim 4, wherein: the carrier used by the supported catalyst is one or a mixture of more than two of the following components: clay, styrene type spherical exchange resin, porous silica gel, precipitated or fumed silica, porous alumina, aluminum silicate, or porous ceramic; the catalyst is an acid type catalyst, and the acid catalyst is one of the following: titanate type, sulfuric acid type, phosphoric acid type or sulfonic acid group type; the mass ratio of the added catalyst to the total mass of the alkoxy silane is 0.001-0.005: 1.

10. The method for preparing the phosphorus-containing silane copolymer for LED bonding according to claim 4, wherein: the mass ratio of the ultrapure water added in the step 2) to the other part of solvent is 1: 0.8-1.2.

Technical Field

The invention relates to the field of silane tackifiers, and particularly relates to a phosphorus-containing silane copolymer for LED bonding and a preparation method thereof.

Background

The LED is called as a fourth-generation lighting source or a green light source, has the characteristics of energy conservation, environmental protection, high luminous efficiency, miniature reliability, long service life and the like, and is widely applied to the fields of aerospace, electronics, electrics, instruments and meters, traffic signals and special lighting. In order to improve the stability and reliability of electronic components and integrated circuits, electronic assembly parts are often required to be encapsulated so as to be adaptable to severe environments such as moisture, salt mist, dust, vibration, impact, high and low temperatures and the like.

The industrial LED packaging material mainly comprises epoxy resin and organic silicon material, and although the performances of yellowing resistance, aging resistance, high temperature resistance and the like of the epoxy resin can not completely meet the application requirements, the epoxy resin has low price and excellent bonding performance, and still has certain application value. The silicone material for LED packaging usually adopts bi-component addition type silicone rubber, vulcanization molding is realized by hydrosilylation of vinyl-terminated silicone oil and hydrogen-containing silicone oil under the action of a platinum catalyst, and the silicone rubber has the characteristics of excellent high and low temperature resistance, water resistance, insulation, vulcanization resistance, radiation resistance, ultraviolet light resistance, small shrinkage and the like, has a remarkable protection effect on an LED, and can effectively prolong the service life of the LED. Although the addition type silicon rubber has higher oxygen index due to the structural characteristics of the addition type silicon rubber, no dripping is caused during combustion, and the heat release rate and the flame propagation rate are lower. However, the addition type liquid silicone rubber which is not modified by flame retardance still has the defect of combustibility, is particularly easy to smolder, and has larger potential safety hazard. And the addition type silicone rubber has low cohesive energy due to the fact that most of the surface of the addition type silicone rubber is nonpolar organic groups after vulcanization, and is lack of groups with reactivity, so that the adhesion to other base materials is poor, and the application range of the addition type silicone rubber is greatly limited. Therefore, it is necessary to develop an addition type silicone pouring sealant for an environment-friendly LED with good flame retardant property, high compatibility and reactivity.

Researchers at home and abroad have conducted some researches on how to improve the adhesion between the addition type liquid silicone rubber and the base material. Currently, there are three main approaches: firstly, the surface of a bonded substrate is treated; secondly, the adhesion of the addition type liquid silicone rubber is improved by adding an adhesion promoter; thirdly, the addition type liquid silicone rubber obtains the adhesiveness by changing the molecular structure of the polyorganosiloxane.

U.S. Pat. No. 4, 3298824, which uses alkoxy and acyloxy group-containing silanes to prime substrates, is effective for long term storage on surfaces and is suitable for use on a wide variety of substrates. Although the method can improve the bonding performance of the addition type liquid silicone rubber and the base material, the method has the disadvantages of complicated process, production period increase, production cost reduction and production efficiency reduction, and the common use of volatile organic solvents can damage the health of human bodies and pollute the environment.

The addition type liquid silicone rubber obtains adhesiveness by changing the molecular structure of the polyorganosiloxane, the method needs to design the molecular structure of the polyorganosiloxane and also needs to carry out polyorganosiloxane modification reaction, the process is complex in the actual production process, the technical requirement is high, the cost is high, and the industrial application prospect is limited.

The operation method for adding the tackifier is simple and easy to implement, and a proper adhesion promoter can be selected according to the surface property and the curing condition of the base material to improve the adhesion property of the addition type silicone rubber and realize the body tackifying. However, the preparation method of most of the adhesion promoters is difficult to control, and the problems of easy poisoning of the catalyst, unobvious tackifying effect and the like also exist, and the preparation method can also have adverse effects on the mechanical property and the curing property of the pouring sealant. Therefore, the development of a novel efficient tackifier is very necessary.

The method for improving the flame retardant property of the organic silicon pouring sealant mainly comprises the addition of a flame retardant. The halogen-free flame retardant mainly comprises aluminum hydroxide, magnesium hydroxide, ammonium polyphosphate, zinc borate and the like, and has the advantages of no halogen, low smoke, low toxicity, low price and the like, but because the compatibility of the flame retardant and a silicon rubber matrix is poor, the surface modification of the flame retardant is often needed to improve the flame retardant property and the mechanical property of the organic silicon pouring sealant. But also increases the cost and the damage to the physical and mechanical properties of the material.

Patent No. CN110078909A, entitled "phosphorus-containing silane-terminated polyether and preparation method thereof", describes a reactive flame retardant with excellent flame retardant properties. The phosphorus-containing silane terminated polyether is obtained by using trihydroxymethyl phosphorus oxide as an initiator to initiate ring-opening polymerization of propylene oxide and ethylene oxide, and then performing ring-opening reaction on terminal hydroxyl and epoxy siloxane after carboxylation. The introduction of the phosphorus element can greatly improve the compatibility of the flame retardant and the matrix, reduce the dosage of the flame retardant and provide excellent flame retardant performance. The phosphorus-containing polyether is synthesized by carboxyl-terminated phosphorus-containing polyether and glycidyl ether alkoxy silane, can be used as a reaction type flame retardant additive to be added into a silane sealant formula, and can also be used as silane modified polyether matrix resin. But the production process is complex, and the product repeatability is poor due to the fact that the open-loop structure cannot be effectively controlled. In addition, only one phosphorus-containing polyether can be obtained by the method, and the method is difficult to realize a good bonding effect with various substrates. Meanwhile, the prepared phosphorus-containing polyether has a relatively small proportion of hydrolysis groups, and when the molecular weight is too large, hydrolysis is difficult due to the steric hindrance, so that effective reactivity cannot be provided.

Therefore, it is not easy to find a method for preparing a phosphorus-containing silane copolymer which is versatile, stable, simple, and environmentally friendly, while providing excellent adhesion properties and flame retardancy.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide the phosphorus-containing silane copolymer for LED bonding, which has good compatibility, high flame retardance and good bonding property, and the preparation method thereof.

The invention provides a phosphorus-containing silane copolymer for LED bonding, which has a structural formula shown as a formula I:

in the above formula, Q is methoxy or ethoxy; m is a carbon chain number of C₁～C₄An alkoxy group of (a); r₃、R₅、R₇、R₉Each represents a methyl group or a carbon chain number C₁～C₄An alkoxy group of (a); r₁Represents a phosphorus-containing organic group; r₂、R₄、R₆、R₈Respectively represent vinyl, allyl, glycidoxyalkyl, methacryloxyalkyl, acryloxypropyl, mercaptopropyl, the number of carbon chains is C₁～C₈Alkyl and carbon chain number of C₁～C₄One of the alkoxy groups of (a); a is 1 or 2; b. c, d and e are positive integers of 0-8.

The phosphorus-containing silane copolymer for LED bonding adopts the molecular structure, solves the technical difficulty of structural defects of the traditional LED bonding accelerator, and has the core advantages that: firstly, phosphorus is introduced into an organic silicon polymer, so that excellent thermal stability, flame retardance and antistatic property are endowed; compared with silane monomers, the silane copolymer has more organic groups in the same unit volume, generates less hydrolytic alcohol during the action, and is more environment-friendly; thirdly, enough active reaction groups are constructed in the molecular structure, the functional groups can generate strong interaction with the silicon rubber and the base material, and proper action groups can be selected according to the surface property and the curing condition of the base material to improve the bonding performance of the addition type silicon rubber, for example, a sulfhydryl group can generate chelation with metal to increase the bonding performance to the metal base material; the vinyl and allyl have good adhesive property to base materials such as polypropylene and the like due to structural similarity; epoxy groups, methacryloxyalkyl groups, and acryloxypropyl groups are preferred for their reactivity to bond to substrates such as unsaturated polyesters.

Further, R is₁The structural formula of the organic group containing phosphorus is shown as formulas II-IV:

the phosphorus-containing silane copolymer provided by the invention realizes the synergistic effect of silicon and phosphorus by introducing the phosphorus-containing group, so that the thermal stability and the flame retardant property of the addition type silicone rubber are effectively improved, and the compatibility of the flame retardant and a matrix is improved.

Further, in the formula I, the values of a, b, c, d and e satisfy: a + b + c + d + e is more than or equal to 6 and less than or equal to 22, which can meet the compatibility of the phosphorus-containing silane copolymer and matrix resin and the proper crosslinking degree, and b + c + d + e is more than or equal to 5a, namely, the content of phosphorus-containing silane is controlled in the reaction process, if the content of phosphorus-containing silane is excessive in the reaction process, the polymerization reaction is difficult, and the adhesion is influenced.

The invention also discloses a preparation method of the phosphorus-containing silane copolymer for LED bonding, which comprises the following steps:

1) sequentially adding one or more of alkoxysilane, phosphorus-containing silane, solvent and supported catalyst into a three-neck flask with a reflux condenser, and continuously and uniformly stirring at room temperature to obtain a silane reaction solution; the molar ratio of all the added alkoxy silane to the added phosphorus-containing silane is 5-10: 1;

2) adding ultrapure water into the other part of solvent, uniformly mixing to obtain a mixed solution, and slowly dropwise adding the mixed solution into the silane reaction solution obtained in the step 1) at the temperature of 45-55 ℃; after the dropwise addition is finished, the reaction is continued for 2 to 4 hours under the condition of heat preservation, and the reaction is complete when the water content in the detection system is less than 2000 ppm;

3) distilling to remove the solvent in the reaction liquid obtained in the step 2), and filtering out the solid catalyst to obtain the phosphorus-containing silane copolymer for LED bonding.

The preparation method has the advantages that: firstly, the whole system can be in homogeneous reaction by using a solvent, and the reaction speed and the heat release condition can be controlled, so that excessive local polymerization is avoided; secondly, the used solid catalyst and solvent can be effectively recycled, and meanwhile, the neutralization step is omitted, so that the process cost is reduced; thirdly, the reaction degree can be determined by detecting the moisture content in the system, and the reaction process is convenient to monitor.

Further, the molecular formula of the alkoxy silane is shown as the formula V:

Y-Si(R₁₀)_n(OR₁₁)_(3-n)formula V;

when formula V represents vinylsilane, Y is vinyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents allylsilane, Y is allyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents glycidoxyalkylsilane, Y is glycidoxypropyl or epoxycyclohexylethyl; r₁₀Is methyl; r₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents a methacryloxypropyl radical, Y is methacryloxypropyl radical; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents an acryloxysilane, Y is acryloxypropyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents mercaptopropyl silane, Y is mercaptopropyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when formula V represents an alkylalkoxysilane, Y is one of the following: methyl, ethyl, propyl, n-octyl, cyclohexyl, isobutyl; r₁₀Is methyl, R₁₁Is C₁～C₄N is an integer of 0 or 1;

when the formula of formula V represents an orthosilicate silane, Y is methoxy, ethoxy, or propoxy; r₁₀Is methyl, R₁₁Is C₁～C₄Alkyl of (2), Y group and R₁₁Wherein the carbon number is the same, and n is 0;

further, the phosphorus-containing silane is one of four silanes of the following formulas IV-VII:

preferably, when the alkoxysilane is a vinyl silane, the vinyl silane is one of the following: vinyltrimethoxysilane, vinyltriethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane;

when the alkoxy silane is allyl silane, the allyl silane is one of the following: allyltrimethoxysilane, allyltriethoxysilane, allylmethyldimethoxysilane, allylmethyldiethoxysilane;

when the alkoxysilane is a glycidoxyalkylsilane, the glycidoxyalkylsilane is one of the following: 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane;

when the alkoxysilane is a methacryloxyalkylsilane, the methacryloxyalkylsilane is one of the following: methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropylmethyldiethoxysilane;

when the alkoxysilane is an acryloxysilane, the acryloxysilane is one of: acryloxypropyltrimethoxysilane, acryloxypropyltriethoxysilane, acryloxypropylmethyldimethoxysilane, acryloxypropylmethyldiethoxysilane;

when the alkoxy silane is mercaptopropyl silane, the mercaptopropyl silane is one of the following: mercaptopropyl trimethoxysilane, mercaptopropyl triethoxysilane, mercaptopropyl methyldimethoxysilane, or mercaptopropyl methyldiethoxysilane;

when the alkoxysilane is an alkylalkoxysilane, the alkylalkoxysilane is one of the following: methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propylmethyldimethoxysilane, propylmethyldiethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, n-octylmethyldimethoxysilane, n-octylmethyldiethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, isobutylmethyldimethoxysilane, isobutylmethyldiethoxysilane;

when the alkoxy silane is orthosilicate ester silane, the orthosilicate ester silane is one of the following: methyl orthosilicate, ethyl orthosilicate and propyl orthosilicate.

Preferably, the solvent is one or a mixture of two or more of the following: methanol, ethanol, isopropanol, propanol, tetrahydrofuran, acetone and butanone. Preferably, the solvent is methanol, ethanol or butanone. The invention adopts the solvent to ensure that the whole system is in homogeneous reaction, and can control the reaction speed and the heat release condition and avoid local excessive polymerization.

Preferably, the carrier used in the supported catalyst is one or a mixture of two or more of the following: clay, styrene type spherical exchange resin, porous silica gel, precipitated or fumed silica, porous alumina, aluminum silicate, or porous ceramic; preferably, the carrier used by the supported catalyst is styrene type spherical exchange resin or porous silica gel. The catalyst is an acid type catalyst, and the acid catalyst is one of the following: titanate type, sulfuric acid type, phosphoric acid type, or sulfonic acid group type. Preferably, the acidic catalyst is trimethylsilyl phosphoric acid or trifluoropropyl sulfonic acid. The catalyst can be effectively recycled, and meanwhile, the neutralization step is omitted, so that the process cost is reduced. The mass ratio of the added catalyst to the total mass of the alkoxy silane is 0.001-0.005: 1.

Preferably, the mass ratio of the ultrapure water added in the step 2) to the other part of the solvent is 1: 0.8-1.2.

The invention has the beneficial effects that:

1. according to the invention, through molecular structure design, phosphorus element is introduced into the organic silicon polymer, so that the organic silicon polymer is endowed with excellent thermal stability, flame retardance and antistatic property, and compared with the common polymer, the organic silicon polymer flame retardant has the advantages that the compatibility of the flame retardant and a matrix can be effectively improved, the using amount of the flame retardant is reduced, and the organic silicon polymer flame retardant has a wider application prospect;

2. the invention can carry out customized synthesis of the phosphorus-containing silane copolymer according to the use condition and scene, and endows various excellent performances to the phosphorus-containing silane copolymer by introducing different types of silane. For example, a long-chain alkyl group is designed in a molecular chain to provide hydrophobicity, and a sulfydryl group is designed in the molecular chain to further enhance the adhesion to metal; active groups such as epoxy groups, vinyl groups, acryloxy groups and the like are designed in a molecular chain to provide better adhesion, compatibility and reactivity with a base material;

3. compared with silane monomers, the phosphorus-containing silane copolymer has higher effective components in the same unit volume and generates less hydrolytic alcohol during the action;

4. the phosphorus-containing silane copolymer has the advantages of simple and convenient synthesis process, low VOC, environmental friendliness, good storage stability and the like.

Detailed Description

Example 1

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 76.8g (0.2mol) of DOPO-KH-1, 148g (1mol) of vinyltrimethoxysilane, 225g of methanol and a porous silica gel supported tetratrimethylsilyltitanate catalyst with the catalyst content of 0.45g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 17.28g (0.96mol) of ultrapure water and 17.28g of methanol, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And detecting the water content of the reaction solution to 358ppm, filtering out the solid catalyst, and removing methanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 2

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 76.8g (0.2mol) of DOPO-KH-2, 324g (2mol) of allyl trimethoxy silane, 400g of methanol and a porous silica gel supported tetratrimethyl silicon titanate catalyst with the catalyst content of 0.80g are sequentially added into a three-neck flask and uniformly mixed; and then 31.68g (1.76mol) of ultrapure water and 32g of methanol are mixed and added into a constant-pressure dropping funnel to start dropping reaction, the reaction temperature is controlled to be 45-50 ℃, the dropping time is 1h, and after the dropping is finished, the mixture is kept under heat and stirred for 2 h. Then detecting the water content of the reaction solution to be 427ppm, filtering out the solid catalyst, and removing the methanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 3

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 72.8g (0.2mol) of DOPO-VTS-1, 330.4g (1.4mol) of glycidoxypropyltrimethoxysilane, 403.2g of methanol and a silica gel supported dodecylbenzene sulfonic acid catalyst with the catalyst content of 0.40g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 23.04g (1.28mol) of ultrapure water and 23g of methanol, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And detecting the water content of the reaction solution to 520ppm, filtering out the solid catalyst, and removing methanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 4

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 72.8g (0.2mol) of DOPO-VTS-1, 74g (0.5mol) of vinyltrimethoxysilane, 118g (0.5mol) of glycidoxypropyltrimethoxysilane, 265g of acetone and a silica gel supported dodecylbenzenesulfonic acid catalyst with the catalyst content of 0.53g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 18g of acetone, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And detecting the moisture content of the reaction solution to be 425ppm, filtering out the solid catalyst, and removing methanol and acetone by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 5

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 81.2g (0.2mol) of DOPO-VTS-2, 74g (0.5mol) of vinyltrimethoxysilane, 124g (0.5mol) of methacryloxypropyltrimethoxysilane, 279g of acetone and a silica gel supported trifluoropropylsulfonic acid catalyst with the catalyst content of 0.84g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 18g of acetone, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And then detecting the water content of the reaction solution to be 513ppm, filtering out the solid catalyst, and removing methanol, ethanol and acetone by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 6

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 76.8g (0.2mol) of DOPO-KH-1, 74g (0.5mol) of vinyltrimethoxysilane, 76g (0.5mol) of methyl orthosilicate, 227g of methanol and a silica gel supported dodecylbenzene sulfonic acid catalyst with the catalyst content of 0.45g are sequentially added into a three-neck flask and uniformly mixed; then 18g (1mol) of ultrapure water and 18g of methanol are mixed and added into a constant-pressure dropping funnel to start the dropping reaction, the reaction temperature is controlled between 45 ℃ and 50 ℃, the dropping time is 1h, and the stirring is continued for 2h under heat preservation after the dropping is finished. And detecting the water content of the reaction solution to 358ppm, filtering out the solid catalyst, and removing methanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 7

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 76.8g (0.2mol) of DOPO-KH-2, 74g (0.5mol) of vinyltrimethoxysilane, 98g (0.5mol) of mercaptopropyltrimethoxysilane, 249g of methanol and 0.86g of silica gel supported dodecylbenzene sulfonic acid catalyst are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 25g of methanol, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And then detecting the water content of the reaction solution to be 411ppm, filtering out the solid catalyst, and removing methanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 8

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 72.8g (0.2mol) of DOPO-VTS-1, 74g (0.5mol) of vinyltrimethoxysilane, 82g (0.5mol) of propyltrimethoxysilane, 233g of methanol and a porous silica gel supported tetratrimethylsilyltitanate catalyst with the catalyst content of 0.78g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 21.6g of methanol, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And detecting the water content of the reaction solution to 568ppm, filtering out the solid catalyst, and removing methanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 9

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 81.2g (0.2mol) of DOPO-VTS-2, 118g (0.5mol) of glycidoxypropyltrimethoxysilane, 72g (0.5mol) of acryloyloxypropyltrimethoxysilane, 271g of acetone and a porous silica gel supported tetratrimethyl silicon titanate catalyst with the catalyst content of 0.81g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 14.4g of acetone, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And then detecting the water content of the reaction solution to be 511ppm, filtering out the solid catalyst, and removing methanol, ethanol and acetone by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 10

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 76.8g (0.2mol) of DOP0-KH-1, 118g (0.5mol) of glycidoxypropyltrimethoxysilane, 68g (0.5mol) of methyltrimethoxysilane, 267g of acetone and a porous ceramic supported trimethylsilyl phosphoric acid catalyst with the catalyst content of 0.27g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 18g of acetone, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 50-55 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And then detecting the moisture content of the reaction solution to be 369ppm, filtering out the solid catalyst, and removing methanol and acetone by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 11

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 76.8g (0.2mol) of DOP0-KH-2, 118g (0.5mol) of glycidoxypropyltrimethoxysilane, 119g (0.5mol) of mercaptopropyltriethoxysilane, 318g of ethanol and a porous ceramic supported trimethylsilyl phosphate catalyst with the catalyst content of 1.18g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 18g of ethanol, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 4h under heat preservation after the dropping is finished. And detecting the water content of the reaction solution to 472ppm, filtering out the solid catalyst, and removing methanol and ethanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 12

A magnetic rotor was placed in a 1L three-necked flask, and a thermometer, a condenser tube, a constant pressure dropping funnel and a magnetic stirring heating device were installed. 72.8g (0.2mol) of DOPO-VTS-1, 118g (0.5mol) of glycidoxypropyltrimethoxysilane, 81g (0.5mol) of allyltrimethoxysilane, 272g of methanol and a porous ceramic supported trimethylsilyl phosphoric acid catalyst with the catalyst content of 0.81g are sequentially added into a three-neck flask and uniformly mixed; and then, mixing 18g (1mol) of ultrapure water and 18g of methanol, adding the mixture into a constant-pressure dropping funnel, starting dropping reaction, controlling the reaction temperature to be 45-50 ℃, keeping the dropping time for 1h, and continuing stirring for 2h under heat preservation after the dropping is finished. And detecting the water content of the reaction solution to 314ppm, filtering out the solid catalyst, and removing methanol by reduced pressure distillation to obtain the phosphorus-containing silane copolymer for LED bonding.

Example 13

The phosphorus-containing silane copolymer synthesized in example 1 was used to prepare the corresponding silicone potting adhesive according to the following preparation method, and then the silicone potting adhesive was subjected to a correlation performance test.

The preparation method of the organic silicon pouring sealant comprises the following steps:

step 1, base material preparation: weighing 3.5kg of the mixture with the viscosity of 500-1000 mm²Adding 10kg of ammonium polyphosphate with the particle size of 5-10 um and vinyl-terminated silicone oil/s into a high-speed dispersion machine, and uniformly mixing to obtain the base material.

Step 2, preparing a component A: 4kg of base material, 0.005kg of Kanst platinum catalyst and 1kg of vinyl silicone resin are stirred for 4 hours at the rotating speed of 500r/min to prepare a component A.

Step 3, preparing a component B: 4kg of base material, 0.3kg of the phosphorus-containing silane copolymer obtained in example 1 and 0.7kg of hydrogen-containing silicone oil were stirred at a rotation speed of 500r/min for 4 hours to obtain component B.

Step 4, glue preparation: a, B components are uniformly mixed according to the mass ratio of 1: 1, vacuum defoamed for 15 minutes, poured into a corresponding mold at room temperature, vulcanized for 1 hour at 80 ℃ and prepared into a standard sample for performance test.

Examples 14 to 24

The phosphorus-containing silane copolymer synthesized in examples 2 to 12 is used to prepare the corresponding organic silicon pouring sealant according to the preparation method of example 13, the phosphorus-containing silane copolymer of example 2 is used to prepare the organic silicon pouring sealant of example 14, and so on.

Comparative example

On the basis of the preparation method of the example 13, when the component B is prepared in the step 3, the phosphorus-containing silane copolymer is not added, and other steps, the added components and the content are the same as those of the example 13, so that the organic silicon pouring sealant of the comparative example is obtained.

The adhesive strength and the oxygen index of the silicone pouring sealant obtained in examples 13-24 and the comparative example were measured, and the test standards were as follows:

bonding strength: according to the test of GB/T7124-2008, the moving speed of the beam is 5mm/min

Oxygen index: testing according to GB5454-85

The test results are shown in the following table:

as can be seen from the test data in the table, the sealants prepared in examples 1 to 12 have no catalyst poisoning phenomenon. Compared with the control experimental data, the organic silicon pouring sealant prepared by adding the phosphorus-containing silane copolymer has obviously improved bonding strength to different base materials and the oxygen index of the organic silicon pouring sealant. In addition, in comparison with examples 13 and 16, the indexes of the organosilicon potting adhesive prepared by copolymerization of more than two silanes are improved compared with the indexes of the organosilicon potting adhesive prepared by copolymerization of single silane and phosphorus-containing silane, and the application field is wider. The adhesive strength of the aluminum materials is the best in examples 19 and 23 containing mercapto groups; on the other hand, the PET material of example 21 containing epoxy group and acryloxypropyl group showed the best adhesion effect. Other materials are also tackifiers with different bonding effects according to the reactivity and similarity principle between groups, so that the most suitable tackifier can be selected according to different application scenes of the LED.

It should be noted that, although the above embodiments have been described herein, the invention is not limited thereto. Therefore, based on the innovative concepts of the present invention, the technical solutions of the present invention can be directly or indirectly applied to other related technical fields by making changes and modifications to the embodiments described herein or by using equivalent structures or equivalent processes performed in the present specification, and are included in the scope of the present invention.