Boron-containing organic silicon tackifier and preparation method and application thereof
阅读说明：本技术 一种含硼有机硅增粘剂及其制备方法和应用 (Boron-containing organic silicon tackifier and preparation method and application thereof ) 是由 梁乐成 张文彬 袁有学 钱帆 于 2021-08-17 设计创作，主要内容包括：本发明提供了一种含硼有机硅增粘剂及其制备方法和应用,涉及有机硅高分子合成技术领域。本发明通过采用具有一定链节长度的线性聚硅氧烷与带联苯硼酸结构、带丙烯酸基团的丙烯酸酯连接成一个新的含硼有机硅聚合物大分子,即含硼有机硅增粘剂,使得该含硼有机硅增粘剂具有良好的粘结性能、耐热老化性能和耐冷热冲击性能。(The invention provides a boron-containing organic silicon tackifier and a preparation method and application thereof, and relates to the technical field of organic silicon polymer synthesis. According to the invention, linear polysiloxane with a certain chain length, a biphenyl boric acid structure and acrylic ester with an acrylic group are connected into a novel boron-containing organic silicon polymer macromolecule, namely the boron-containing organic silicon tackifier, so that the boron-containing organic silicon tackifier has good bonding property, thermal aging resistance and cold and heat shock resistance.)
1. The boron-containing organic silicon tackifier is characterized in that the structural formula of the boron-containing organic silicon tackifier is shown as the formula (I):
wherein R isnComprises at least one of alkyl and carbonyl substituent;
m and q are any natural number from 0 to 15.
2. The boron-containing silicone adhesion promoter of claim 1, wherein m is 3 or 5.
3. The method of preparing the boron-containing silicone adhesion promoter of claim 1, comprising the steps of:
(1) reacting biphenyl boric acid and a siloxane compound serving as initial reactants at 45-55 ℃ to obtain an intermediate product A;
(2) and (3) taking the intermediate product A and the diacrylate as reactants, regulating the reaction temperature to 80-85 ℃ under the catalysis of a Pt catalyst, and reacting to generate the boron-containing organic silicon tackifier.
4. The method of claim 3, wherein the siloxane compound comprises polysiloxane and tetramethyldisiloxane.
5. The method according to claim 3, wherein the biphenylboronic acid comprises at least one of boronic acid, 3-biphenylboronic acid, 4-propylbiphenylboronic acid, 4-butylbiphenylboronic acid, 4-pentylbiphenylboronic acid, 4-hexylbiphenylboronic acid, 3, 5-diethylcarbonyl-4-biphenylboronic acid and 4-biphenylboronic acid pinacol ester.
6. The method of claim 3, wherein the diacrylate is 1, 6-hexanediol diacrylate.
7. Use of the boron-containing silicone adhesion promoter of claim 1 or 2 in a silicone encapsulant.
8. The use of the boron-containing silicone adhesion promoter of claim 7 in a silicone encapsulating adhesive, wherein the silicone encapsulating adhesive comprises the following components in parts by weight: 60-80 parts of phenyl vinyl silicone resin, 8-15 parts of phenyl vinyl silicone oil, 15-20 parts of a hydrogen-containing cross-linking agent, 1-4 parts of the boron-containing organic silicon tackifier, 0-0.1 part of chloroplatinic acid and 0-0.1 part of 1-ethyncyclohexanol.
9. The use of the boron-containing silicone adhesion promoter of claim 8 in a silicone encapsulating adhesive, wherein the silicone encapsulating adhesive comprises the following components in parts by weight: 70 parts of phenyl vinyl silicone resin, 10 parts of phenyl vinyl silicone oil, 18 parts of a hydrogen-containing cross-linking agent, 2 parts of the boron-containing organic silicon tackifier, 0.015 part of chloroplatinic acid and 0.01 part of 1-acetylene cyclohexanol.
Technical Field
The invention relates to the technical field of organic silicon polymer synthesis, in particular to a boron-containing organic silicon tackifier and a preparation method and application thereof.
Background
Although the LED organic silicon packaging adhesive has the characteristics of high transparency, good thermal stability, small stress cracking and the like, the adhesive force between the LED organic silicon packaging adhesive and a base material is poor, and at present, the adhesion problem between the LED organic silicon packaging adhesive and the base material is solved by adding a tackifier into an organic silicon material. However, in the actual production process, the conventional tackifier has poor compatibility with silicone oil, and has no obvious tackifying effect on the base material, and the adhesive force is obviously reduced under certain temperature and humidity, so that the silicone resin material and the chip base material are seriously separated.
Chinese patent application CN108239284A discloses a preparation method and application of an organosilicon adhesive for addition type silicone rubber, wherein organic alkoxy silane such as diphenyl dimethoxy silane and dimethyl dimethoxy silane and gamma-glycidyl ether oxypropyl trimethoxy silane and gamma-methyl propionyl oxypropyl trimethoxy silane are adopted to react for a certain time at a proper temperature under the catalysis of concentrated hydrochloric acid to prepare the organosilicon tackifier with epoxy group and ester group and high refractive index.
Chinese patent application CN102775611A discloses a method for synthesizing and producing a tackifier, which is characterized in that hydroxy silicone oil, gamma-glycidyl ether oxypropyl trimethoxy silane and gamma-methyl propionyl oxypropyl trimethoxy silane react under the catalysis of organic tin to obtain a light yellow liquid organic silicon tackifier.
In the traditional method, the tackifier is synthesized by using the cohydrolysis and condensation of organic siloxane and epoxy silane, so that the side reaction is more and the structure is uncontrollable in the synthesis process; the tackifying effect of the synthetic tackifier is general; part of the tackifier is catalyzed and synthesized by a homogeneous catalyst, the residual homogeneous catalyst is difficult to remove, the residual homogeneous catalyst is easy to cause influence when being added into silicon rubber, and the organic tin can further poison the platinum catalyst.
Disclosure of Invention
The invention mainly aims to provide a boron-containing organic silicon tackifier, and a preparation method and application thereof, and aims to improve the bonding property, the heat and aging resistance and the cold and heat shock resistance of the tackifier.
In order to achieve the above object, in a first aspect, the present invention provides a boron-containing silicone tackifier, wherein the structural formula of the boron-containing silicone tackifier is represented by formula (I):
wherein Rn comprises at least one of alkyl and carbonyl substituent;
m and q are any natural number of 1-15.
In the technical scheme of the invention, linear polysiloxane with a certain chain length is adopted to be connected with acrylate with a biphenyl boric acid structure and an acrylic group to form a novel boron-containing organic silicon polymer macromolecule (namely the boron-containing organic silicon tackifier), and the boron-containing organic silicon tackifier has good bonding property, thermal aging resistance and cold and heat shock resistance.
The boron-containing organic silicon tackifier disclosed by the invention is added into a basic organic silicon resin composition, so that the organic silicon resin composition can be well adhered to a silver coating, and has heat aging resistance and cold and heat shock resistance after being cured.
As a preferred embodiment of the boron-containing silicone adhesion promoter of the present invention, m is equal to 3 or 5.
In the molecular structure of the boron-containing organic silicon tackifier, linear siloxane molecular groups have great influence on the adhesive property and the cold and heat shock resistance of the boron-containing organic silicon tackifier, namely the m values are different, and the adhesive property, the heat resistance and the cold and heat shock resistance of the boron-containing organic silicon tackifier are different. Wherein, when m is equal to 3 or 5, the boron-containing organic silicon tackifier has better bonding performance, heat resistance and cold and hot shock resistance. When the value of m is more than 5, the larger the value of m is, the better the flexibility and the cold and heat shock resistance of the boron-containing organic silicon tackifier are, but as the value of m is increased, the bonding performance and the heat resistance of the boron-containing organic silicon tackifier are greatly reduced, which adversely affects the cold and heat shock effect, so that the comprehensive performance is the best when m is equal to 3 or 5.
In a second aspect, the invention further provides a preparation method of the boron-containing organosilicon tackifier, which comprises the following steps:
(1) reacting biphenyl boric acid and a siloxane compound serving as initial reactants at 45-55 ℃ to obtain an intermediate product A;
(2) and (3) taking the intermediate product A and the diacrylate as reactants, regulating the reaction temperature to 80-85 ℃ under the catalysis of a Pt catalyst, and reacting to generate the boron-containing organic silicon tackifier.
In the technical scheme of the invention, the reaction equation of the step (1) is shown as the following formula (II):
the reaction equation of the step (2) is shown as the following formula (III):
in addition, the Pt catalyst in the step (2) is a platinum catalyst having different ligands, and the content of metal Pt in the platinum catalyst is 0.2%. In the preparation process of the boron-containing organic silicon tackifier, the reaction temperature is the key for influencing whether the synthesis reaction is smoothly carried out, and when the synthesis temperature of the steps (1) and (2) exceeds the temperature range, the target product cannot be synthesized.
The preparation method of the application basically has no side reaction, the structure of the target product is controllable, the catalyst is easy to remove, and the stable catalytic performance can be kept in a reaction system for a long time.
As a preferred embodiment of the method for preparing the boron-containing organosilicon adhesion promoter of the present invention, the siloxane compounds include polysiloxane and tetramethyldisiloxane.
In the technical scheme of the invention, the m value of the polysiloxane is any natural number from 1 to 15, and the q value of the diacrylate is any natural number from 1 to 15.
As a preferred embodiment of the method for preparing the boron-containing organosilicon tackifier of the present invention, the biphenyl boric acid includes at least one of boric acid, 3-biphenyl boric acid, 4-propyl biphenyl boric acid, 4-butyl biphenyl boric acid, 4-pentyl biphenyl boric acid, 4-hexyl biphenyl boric acid, 3, 5-diethyl carbonyl-4-biphenyl boric acid, and 4-biphenyl boric acid pinacol ester.
In a preferred embodiment of the method for preparing the boron-containing organosilicon tackifier of the present invention, the diacrylate is 1, 6-hexanediol diacrylate.
In a third aspect, the invention also provides an application of the boron-containing organic silicon tackifier in organic silicon packaging glue.
As a preferred embodiment of the application of the boron-containing organic silicon tackifier in the organic silicon packaging adhesive, the organic silicon packaging adhesive comprises the following components in parts by weight: 60-80 parts of phenyl vinyl silicone resin, 8-15 parts of phenyl vinyl silicone oil, 15-20 parts of a hydrogen-containing cross-linking agent, 1-4 parts of the boron-containing organic silicon tackifier, 0-0.1 part of chloroplatinic acid and 0-0.1 part of 1-ethyncyclohexanol.
As a preferred embodiment of the application of the boron-containing organic silicon tackifier in the organic silicon packaging adhesive, the organic silicon packaging adhesive comprises the following components in parts by weight: 70 parts of phenyl vinyl silicone resin, 10 parts of phenyl vinyl silicone oil, 18 parts of a hydrogen-containing cross-linking agent, 2 parts of the boron-containing organic silicon tackifier, 0.015 part of chloroplatinic acid and 0.01 part of 1-acetylene cyclohexanol.
Compared with the prior art, the invention has the beneficial effects that:
according to the technical scheme, linear polysiloxane with a certain chain length, a biphenyl boric acid structure and acrylic ester with an acrylic group are connected to form a novel boron-containing organic silicon polymer macromolecule (namely the boron-containing organic silicon tackifier), and the boron-containing organic silicon tackifier has good bonding performance, thermal aging resistance and cold and heat shock resistance.
The boron-containing organic silicon tackifier is added into a basic organic silicon resin composition to prepare the organic silicon packaging adhesive, so that the cured organic silicon packaging adhesive has good bonding property, thermal aging resistance and cold and heat shock resistance.
Detailed Description
To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to the following specific examples.
Example 1
The preparation method of the boron-containing organosilicon tackifier comprises the following steps:
(1) 14.10g of tetramethyldisiloxane, 1.65g of concentrated hydrochloric acid, 10g of purified water and 48g of three-chain hydroxy silicone oil are added into a 500ml three-neck flask provided with a constant pressure dropping funnel, a condenser and a thermometer, stirred and heated to 50 ℃ on an oil bath, 26.82g of 4-pentylbiphenyl boric acid is dissolved in 130g of methanol, dropped into the three-neck flask through the constant pressure dropping funnel, and refluxed and reacted for 6 hours at 50 ℃ to obtain 84.48g of colorless and transparent liquid product (namely intermediate A);
(2) 5g of the intermediate product A was put into a 100ml three-necked flask equipped with a constant pressure dropping funnel, a condenser and a thermometer, and heated to 80 ℃ with stirring on an oil bath, and then a mixed solution containing 0.1520gPt catalyst (0.2%) and 25.41g of 1, 6-hexanediol diacrylate was slowly (30 minutes) dropped into the three-necked flask through the constant pressure dropping funnel, the temperature was maintained between 80 ℃ and 85 ℃, and thereafter the reaction was maintained at 85 ℃ for 8 hours, whereby 27.37g of a pale yellow transparent liquid product (i.e., a boron-containing silicone tackifier) was obtained, and the theoretical mass was 30.41 g.
The molecular structure of the boron-containing silicone adhesion promoter prepared in this example was m-3.
Example 2
The preparation method of the boron-containing organosilicon tackifier comprises the following steps:
(1) 14.10g of tetramethyldisiloxane, 1.65g of concentrated hydrochloric acid, 10g of purified water and 77.6g of pentamer hydroxysilicone oil are added into a 500ml three-neck flask provided with a constant pressure dropping funnel, a condenser and a thermometer, stirred and heated to 50 ℃ on an oil bath, 26.82g of 4-pentylbiphenyl boric acid is dissolved in 130g of methanol, dropped into the three-neck flask through the constant pressure dropping funnel, and refluxed and reacted for 6 hours at 50 ℃ to obtain 112.59g of colorless and transparent liquid product (namely intermediate A);
(2) 10g of the intermediate product A was placed in a 100ml three-necked flask equipped with a constant pressure dropping funnel, condenser and thermometer, heated to 80 ℃ with stirring in an oil bath, and then a mixed solution containing 0.1244gPt of catalyst (0.2%) and 14.89g of 1, 6-hexanediol diacrylate was slowly (30 minutes) added dropwise to the three-necked flask via the constant pressure dropping funnel, the temperature was maintained between 80 ℃ and 85 ℃, and thereafter the reaction was maintained at 85 ℃ for 8 hours to obtain 22.40g of a pale yellow transparent liquid product (i.e., a boron-containing silicone tackifier), the theoretical mass of which was 24.89 g.
The molecular structure of the boron-containing silicone adhesion promoter prepared in this example was m-5.
Example 3
The preparation method of the boron-containing organosilicon tackifier comprises the following steps:
(1) 14.10g of tetramethyldisiloxane, 1.65g of concentrated hydrochloric acid, 10g of purified water and 107.2g of seven-chain hydroxy silicone oil are added into a 500ml three-neck flask provided with a constant pressure dropping funnel, a condenser and a thermometer, stirred and heated to 50 ℃ on an oil bath, 26.82g of 4-pentylbiphenyl boric acid is dissolved in 130g of methanol, dropped into the three-neck flask through the constant pressure dropping funnel, and refluxed and reacted for 6 hours at 50 ℃ to obtain 140.71g of colorless and transparent liquid product (namely intermediate A);
(2) 15g of the intermediate product A was charged into a 100ml three-necked flask equipped with a constant pressure dropping funnel, condenser and thermometer, heated to 80 ℃ with stirring in an oil bath, and then a mixed solution containing 0.1950gPt of the catalyst (0.2%) and 24.00g of 1, 6-hexanediol diacrylate was slowly (30 minutes) dropped into the three-necked flask through the constant pressure dropping funnel, the temperature was maintained between 80 ℃ and 85 ℃, and thereafter the reaction was maintained at 85 ℃ for 8 hours to obtain 35.10g of a pale yellow transparent liquid product (i.e., a boron-containing silicone tackifier) having a theoretical mass of 39.0 g.
The molecular structure of the boron-containing silicone adhesion promoter prepared in this example was 7.
Comparative example 1
The preparation method of the boron-containing organosilicon tackifier of the comparative example comprises the following steps:
(1) adding 14.10g of tetramethyldisiloxane, 1.65g of concentrated hydrochloric acid and 10g of purified water into a 500ml three-neck flask provided with a constant pressure dropping funnel, a condenser and a thermometer, stirring and heating the mixture on an oil bath to 50 ℃, dissolving 26.82g of 4-pentylbiphenyl boric acid into 130g of methanol, dropping the mixture into the three-neck flask through the constant pressure dropping funnel, and carrying out reflux reaction at 50 ℃ for 6 hours to obtain 40.25g of colorless and transparent liquid product (namely intermediate product A);
(2) 5g of the intermediate product A was put into a 100ml three-necked flask equipped with a constant pressure dropping funnel, a condenser and a thermometer, and heated to 80 ℃ with stirring in an oil bath, and then a mixed solution containing 0.1790gPt catalyst (0.2%) and 30.80g of 1, 6-hexanediol diacrylate was slowly (30 minutes) dropped into the three-necked flask through the constant pressure dropping funnel, the temperature was maintained between 80 ℃ and 85 ℃, and thereafter the reaction was maintained at 85 ℃ for 8 hours, whereby 32.22g of a pale yellow transparent liquid product (i.e., a boron-containing silicone tackifier) was obtained, and the theoretical mass was 35.8 g.
The molecular structure of the boron-containing organosilicon tackifier prepared in the comparative example is m 0.
Example 4
The silicone packaging adhesive of the embodiment comprises the following components in parts by weight: 70 parts of phenyl vinyl silicone resin, 10 parts of phenyl vinyl silicone oil, 18 parts of a hydrogen-containing cross-linking agent, 2 parts of the boron-containing silicone tackifier prepared in example 1, 0.15 part of chloroplatinic acid (0.2%), and 0.01 part of 1-ethynylcyclohexanol.
Example 5
The amount of each component of the silicone sealing adhesive in this embodiment is exactly the same as that in embodiment 4, and the difference from embodiment 4 is only: the adhesion promoter of this example used the boron containing silicone adhesion promoter prepared in example 2.
Example 6
The amount of each component of the silicone sealing adhesive in this embodiment is exactly the same as that in embodiment 4, and the difference from embodiment 4 is only: the adhesion promoter of this example used the boron containing silicone adhesion promoter prepared in example 3.
Comparative example 2
The amount of each component of the silicone packaging adhesive in the comparative example is completely the same as that in example 4, and the difference from example 4 is only that: the adhesion promoter of this comparative example used the boron-containing silicone adhesion promoter prepared in comparative example 1.
Comparative example 3
The amount of each component of the silicone packaging adhesive in the comparative example is completely the same as that in example 4, and the difference from example 4 is only that: the tackifier of this comparative example used the tackifier prepared according to the method of CN 108239284A.
Comparative example 4
The amount of each component of the silicone packaging adhesive in the comparative example is completely the same as that in example 4, and the difference from example 4 is only that: the tackifier of this comparative example used the tackifier prepared according to the method of CN 102775611A.
Experimental example 1
The silicone packaging adhesives prepared in examples 4-6 and comparative examples 2-4 were subjected to performance tests, the performance test standards are as follows, and the performance test results are shown in table 1 below.
1. The silicone packaging adhesive obtained above was filled in the gap between two silver-plated aluminum plates (or PCT/PPA plates) (width: 20 mm; length: 50 mm; thickness 1mm) according to the test method of GBT 13936-. Baking in a hot air circulation oven at 150 ℃ for 180 minutes. After cooling to room temperature, the bond strength after curing was tested in a tensile tester.
2. In a high temperature oven, a heat aging resistance test was performed. The temperature is 280 ℃, the time is 72h, and the thermal weight loss rate of the silica gel is tested. The thermal weight loss rate: recording the mass of the initial organic silicon packaging adhesive as m0Then placing the mixture into a 280 ℃ baking oven for baking for 72 hours, taking out the mixture with the weighed mass m1Thermal weight loss rate [ [ (m)0-m1)/m0]*100％。
3. The encapsulated 2835 lamp beads are placed in a high-low temperature cold-hot impact test box and are calculated once and once at a temperature of between 45 ℃ below zero and 125 ℃ for half an hour.
TABLE 1 Performance test results of Silicone encapsulating adhesive prepared in examples 4-6 and comparative examples 2-4
As can be seen from the data in table 1, the silicone sealing adhesive prepared by mixing the boron-containing silicone tackifier prepared in examples 1 and 2 with phenyl vinyl silicone resin and the like has good adhesive ability, thermal aging resistance and thermal shock resistance without changing the composition ratio of the other components of the silicone sealing adhesive. When the m value of the polysiloxane groups in the molecular structure of the boron-containing organic silicon tackifier is increased to 7, the bonding performance, the heat aging resistance and the cold and heat shock resistance of the prepared organic silicon packaging adhesive begin to be reduced; when the molecular structure of the boron-containing organic silicon tackifier does not contain polysiloxane groups (namely m is 0), the prepared organic silicon packaging adhesive has lower bonding performance, thermal aging resistance and cold and heat shock resistance, and the m value of the polysiloxane groups in the molecular structure of the boron-containing organic silicon tackifier prepared by the application is 3-5, so that the boron-containing organic silicon tackifier has the best effect.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.