Silicone composition, preparation method and die bonding material

Abstract

The invention provides a silicone composition, a preparation method and a solid crystal material. The composition comprises the following components in parts by mass: 80-120 parts of a basic polymer, 0.01-9 parts of a first inhibitor, 0.01-3 parts of a second inhibitor, 10-30 parts of a first toughening diluent, 10-40 parts of a hydrogen-containing organosilicon compound and 0.01-1 part of a platinum catalyst, the first inhibitor is a tackifying inhibitor, and the structural formula is R-(X) n; r is an organopolysiloxane main body, X is one or two of-C = N or-N = C = O, and R at least contains one vinyl group; according to the silicone composition disclosed by the invention, the interaction of the first inhibitor and the second inhibitor is beneficial to improving the room-temperature storage performance of the silicone composition and improving the bonding performance to a chip or a substrate.

Description

Technical Field

[0001] This invention relates to the field of chip bonding technology, and more specifically to a silicone composition. Background Technology

[0002] Die-bonding material is a crucial component of LED devices, significantly impacting their performance across various aspects. It is a vital factor influencing LED photoelectric parameters and reliability. Die-bonding materials are typically used in low-to-medium power dual-electrode chips, and most are transparent with good light transmission. Evaluation of die-bonding materials involves two aspects: the bonding strength between the chip and the substrate, and the on-line time of the die-bonding adhesive. A short on-line time leads to a rushed die-bonding process, causing the adhesive to cure before it is fully bonded to the substrate and chip. This reduces the bond strength between the chip and the substrate, affecting product reliability and stability. Therefore, overcoming these technical problems and defects is a key issue that needs to be addressed. Summary of the Invention

[0003] To address the issue of short online time in current die-bonding materials, this invention provides a silicone composition.

[0004] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: The present invention provides a silicone composition comprising the following components by weight: 80-120 parts of a base polymer, 0.01-9 parts of a first inhibitor, 0.01-3 parts of a second inhibitor, 10-30 parts of a first toughening diluent, 10-40 parts of a hydrogen-containing organosilicon compound, and 0.01-1 parts of a platinum-based catalyst; The first inhibitor is a thickening inhibitor, and the structural formula of the thickening inhibitor is: R-(X)n; wherein, R is an organopolysiloxane host, X is one or both of -C=N or -N=C=O, and R contains at least one vinyl group.

[0005] Optionally, the thickening inhibitor has the following molecular formula: (R1SiO2) 3 / 2 ) a (MeSiO 3 / 2 ) b (R2MeSiO) c (R3MeSiO) d (Me3SiO 1 / 2 ) e (Me2ViSiO 1 / 2 ) f ; Where a, b, c, d, e, and f satisfy the following relations: a > 0, b > 0, c > 0, d > 0, e > 0, f > 0 respectively; R1 includes -N=C=O bonds; R2 is the functional group shown in structural formula I: ; R3 is the functional group shown in structural formula II: .

[0006] Optionally, the second inhibitor includes alkynyl compounds or polyvinyl compounds.

[0007] Optionally, the alkynyl-containing compound includes one or more of 1-ethynyl-1-cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, 3,7,11-trimethyldodecyn-3-ol, 3-methyl-1-pentyn-3-ol, and 2-methyl-3-butyn-2-ol; the polyvinyl compound includes tetramethyltetravinylcyclotetrasiloxane.

[0008] Optionally, the base polymer comprises the following components by weight: 80-120 parts of organopolysiloxane resin, 20-40 parts of a second toughening diluent, and 1-20 parts of fumed silica.

[0009] Optionally, the organopolysiloxane resin includes a vinyl polysiloxane compound, the vinyl polysiloxane compound including at least one vinyl group, and the vinyl content in the vinyl polysiloxane compound is 0.05-1.1 mol / 100g.

[0010] Optionally, the vinyl polysiloxane compounds include one or more of the following: MD linear vinyl polysiloxane, MDT branched vinyl polysiloxane, MTQ bulk vinyl polysiloxane, and MQ type vinyl polysiloxane.

[0011] Optionally, the first toughening diluent comprises a polydimethylsiloxane compound; and / or, The second toughening diluent comprises vinyl silicone oil; The viscosity of the vinyl silicone oil is 50-500 cp.

[0012] Optionally, the polydimethylsiloxane compound includes one or more of methyl polydimethylsiloxane, vinyl polydimethylsiloxane, hydrogen-containing polydimethylsiloxane, and phenyl polydimethylsiloxane.

[0013] Optionally, the hydrogen-containing organosilicon compound includes hydrogen-containing polysiloxane compounds, wherein the viscosity of the hydrogen-containing polysiloxane compound is 1-50 cp and the hydrogen content is 0.6-2 mol / 100g.

[0014] Optionally, the hydrogen-containing polysiloxane compounds include one or more of the following: MD linear hydrogen-containing polysiloxane, MDT branched hydrogen-containing polysiloxane, MT bulk hydrogen-containing polysiloxane, and MQ type hydrogen-containing polysiloxane.

[0015] A second aspect of the present invention provides a method for preparing a silicone composition, comprising the following preparation steps: A silicone composition is formed by mixing a base polymer with a second toughening diluent, a hydrogen-containing organosilicon compound, a platinum-based catalyst, a first inhibitor, and a second inhibitor.

[0016] Optionally, the preparation method of the base polymer is as follows: organic polysiloxane resin, second toughening diluent, and fumed silica are mixed in an internal mixer for 3-6 hours to form a homogeneous base polymer.

[0017] A third aspect of the present invention provides a die-bonding material, which is composed of the silicone composition described above, or prepared by the method for preparing the silicone composition described above.

[0018] According to the silicone composition provided by the present invention, after adding a first inhibitor at room temperature, the nitrogen element contained in the first inhibitor can form a weak interaction with the active groups in the silicone composition at room temperature, occupying the reaction sites of the active groups and making it difficult for silane to react with vinyl groups; after adding a second inhibitor, the second inhibitor coordinates and complexes with the active center of the platinum-based catalyst, forming a stable complex with the platinum-based catalyst, changing the electron cloud density and spatial configuration of the platinum-based catalyst, causing the platinum-based catalyst to temporarily lose its activity, thereby preventing the hydrosilylation reaction; when the silicone composition is heated, the interaction between the platinum-based catalyst and the second inhibitor weakens, the activity of the platinum-based catalyst is restored, and it can catalyze the reaction normally. At this point, the first inhibitor also dissociates from the reaction site, and the reaction proceeds further. After dissociation, the first inhibitor can adsorb onto the surface of the base polymer, changing the properties of the base polymer, reducing its surface energy, increasing the wettability of the silicone composition with the chip or substrate, allowing the silicone composition to spread better on the chip or substrate surface, and improving adhesion. The first inhibitor may also undergo a condensation reaction with active groups in the base polymer, such as hydroxyl groups, to form covalent bonds, thereby increasing the cohesive force and adhesive properties of the base polymer. Through the interaction of the first and second inhibitors, it is beneficial to improve the room temperature storage performance of the silicone composition and enhance its adhesion to the chip or substrate. Detailed Implementation

[0019] To make the technical problems solved, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0020] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; the materials and reagents used are commercially available unless otherwise specified.

[0021] The present invention provides a silicone composition comprising the following components by weight: 80-120 parts of a base polymer, 0.01-9 parts of a first inhibitor, 0.01-3 parts of a second inhibitor, 10-30 parts of a first toughening diluent, 10-40 parts of a hydrogen-containing organosilicon compound, and 0.01-1 parts of a platinum-based catalyst.

[0022] Specifically, the base polymer is any one value or a range of any two values ​​selected from 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 105 parts, 110 parts, 115 parts, or 120 parts; in a preferred embodiment, the base polymer is 80-120 parts.

[0023] When the content of the base polymer is 80-120 parts, the hydrosilylation reaction has a high conversion rate and an appropriate crosslinking density, resulting in the best overall performance of the silicone composition. When the content of the base polymer is higher than 120 parts, the hydrosilylation reaction is incomplete, leaving residual vinyl groups or silane bonds, which affects the performance of the final product.

[0024] Specifically, the first inhibitor is any one value or a range of any two values ​​selected from 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, and 9 parts; in a preferred embodiment, the first inhibitor is 2-7 parts.

[0025] When the mass fraction of the first inhibitor is 0.01-9 parts, it increases the storage stability of the silicone composition at room temperature and increases the adhesion between the silicone composition and the chip at high temperature. When the mass fraction of the first inhibitor is less than 0.01 parts, the content of the first inhibitor is insufficient to occupy the reaction sites of the active group, making it difficult to increase the storage stability of the silicone composition at room temperature. When the mass fraction of the first inhibitor is greater than 9 parts, the first inhibitor occupies too many reactive sites in the silicone composition, making it difficult for the first inhibitor to be fully released when the temperature is raised, which may lead to incomplete hydrosilylation reaction and affect the performance of the final silicone compound.

[0026] Specifically, the second inhibitor is any one value or a range of any two values ​​selected from 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, or 3 parts; in a preferred embodiment, the second inhibitor is 0.1-2 parts.

[0027] When the mass fraction of the second inhibitor is 0.01-3 parts, the silicone composition exhibits good room temperature storage and rapid curing upon heating. When the mass fraction of the second inhibitor is less than 0.01 parts, it cannot form a stable complex with the platinum-based catalyst, resulting in insufficient reduction of the platinum-based catalyst activity and affecting the room temperature storage performance of the silicone composition. When the mass fraction of the second inhibitor is greater than 3 parts, on the one hand, higher temperatures and times are required for the curing of the silicone composition; on the other hand, the second inhibitor does not react with the base polymer, leading to an increase in volatile components in the formulation, which affects the product performance after the silicone composition is cured.

[0028] Specifically, the first toughening diluent is any one value or a range of any two values ​​selected from 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, or 30 parts; in a preferred embodiment, the first toughening diluent is 15-25 parts.

[0029] When the mass fraction of the first toughening diluent is 10-30 parts, the silicone composition has an appropriate workable viscosity, and the hardness and thrust after curing meet the application requirements. When the mass fraction of the first toughening diluent is less than 10 parts, it will result in a high viscosity in the liquid silicone composition, leading to inconvenience in operation. When the mass fraction of the first toughening diluent is greater than 30 parts, it will result in a low viscosity of the silicone composition system, causing adhesive overflow at the edges of the chip during construction. After curing, the cured material will become soft, and the thrust will decrease.

[0030] Specifically, the hydrogen-containing organosilicon compound is any one value or a range of any two values ​​from 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, or 40 parts; in a preferred embodiment, the hydrogen-containing organosilicon compound is 20-30 parts.

[0031] When the mass fraction of the hydrogen-containing organosilicon compound is 10-40 parts, it exhibits a high curing conversion rate and a curing curve that matches the application characteristics. When the mass fraction of the hydrogen-containing organosilicon compound is less than 10 parts, the number of active groups participating in the reaction decreases, the curing reaction rate slows down, and the silicone composition does not cure completely, failing to form a complete cross-linking network and affecting the performance of the final product. When the mass fraction of the hydrogen-containing organosilicon compound is greater than 40 parts, the silicone composition contains too many silane reactive groups, leading to an increase in overall reactivity, which is not conducive to room temperature storage. Too many silane groups will cause the cross-linking density of the silicone composition to be too high, resulting in the cured product becoming brittle, losing good flexibility and elasticity, and easily developing cracks during aging.

[0032] Specifically, the platinum-based catalyst is any one value or a range of any two values ​​from 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part; in a preferred embodiment, the platinum-based catalyst is 0.2-0.8 parts.

[0033] Specifically, platinum group catalysts include one or more of the following: Speier platinum group catalysts, Karstedt platinum group catalysts, and chloroplatinic acid.

[0034] When the mass fraction of the platinum-based catalyst is 0.01-1 part, the silicone composition exhibits good performance in terms of room temperature storage and rapid curing after heating. When the mass fraction of the platinum-based catalyst is less than 0.01 part, the silicone composition will not cure sufficiently after heating, affecting product performance. When the mass fraction of the platinum-based catalyst is greater than 1 part, it will affect the room temperature storage properties of the silicone composition, causing the viscosity to increase during room temperature storage and leading to product failure.

[0035] In one embodiment, the first inhibitor is a thickening inhibitor with the structural formula R-(X)n; wherein R is an organopolysiloxane host, X is one or both of -C=N or -N=C=O, and R contains at least one vinyl group.

[0036] Specifically, the lone pair electrons of the N element in -C=N and -N=C=O in the first inhibitor can undergo a complexation reaction with the platinum metal in the platinum-based catalyst, thus acting as an inhibitor and greatly extending the operation time.

[0037] The first inhibitor has a high boiling point. The vinyl groups in the first inhibitor participate in the reaction without releasing volatile components. This not only reduces VOCs but also improves the luminous flux retention rate after high-temperature aging.

[0038] The vinyl groups contained in the first inhibitor can participate in the addition reaction between the hydrogen-containing organosilicon compound and the base polymer, thereby grafting onto the molecular chain of the base polymer. Meanwhile, -N=C=O can react with the hydroxyl groups bonded to the base polymer, forming -NCOOR and achieving a stable chemical bond. Through this bidirectional reaction, coupling and connection between the chip, the base polymer, and the die-attach adhesive material are achieved, thereby improving the bonding strength between the chip and the substrate. The first inhibitor can also act as an adhesion promoter, improving the adhesion between the die-attach adhesive and the interface.

[0039] This application adds a first inhibitor, a second inhibitor, a first toughening diluent, a hydrogen-containing organosilicon compound, and a platinum-based catalyst to a base polymer. After adding the first inhibitor at room temperature, the nitrogen element contained in the first inhibitor can form a weak interaction with the active groups in the silicone composition at room temperature, occupying the reaction sites of the active groups and making it difficult for the silane to react with the vinyl group. After the addition of the second inhibitor, the second inhibitor coordinates and complexes with the active center of the platinum-based catalyst, forming a stable complex with the platinum-based catalyst. This changes the electron cloud density and spatial configuration of the platinum-based catalyst, causing the platinum-based catalyst to temporarily lose its activity, thereby preventing the hydrosilylation reaction.

[0040] When the silicone composition is heated, the interaction between the platinum-based catalyst and the second inhibitor weakens, and the activity of the platinum-based catalyst recovers, allowing for normal catalytic reaction. At this time, the first inhibitor also dissociates from the reaction site, and the reaction proceeds further. After dissociation, the first inhibitor can adsorb onto the surface of the base polymer, altering the properties of the base polymer, reducing its surface energy, increasing the wettability of the silicone composition with the chip or substrate, allowing the silicone composition to spread better on the chip or substrate surface, and improving adhesion. The first inhibitor may also undergo condensation reactions with active groups in the base polymer, such as hydroxyl groups, to form covalent bonds, thereby increasing the cohesive force and adhesive properties of the base polymer.

[0041] The interaction between the first and second inhibitors improves the room temperature storage performance of the silicone composition and enhances its adhesion to chips or substrates.

[0042] In one embodiment, the thickening inhibitor has the following molecular formula: (R1SiO) 3 / 2 ) a (MeSiO 3 / 2 ) b (R2MeSiO) c (R3MeSiO) d (Me3SiO 1 / 2 ) e (Me2ViSiO 1 / 2 ) f ; Where a, b, c, d, e, and f satisfy the following relations: a > 0, b > 0, c > 0, d > 0, e > 0, f > 0 respectively; R1 includes -N=C=O bonds; R2 is the functional group shown in structural formula I: ; R3 is the functional group shown in structural formula II: .

[0043] Specifically, when the thickening inhibitor has the following molecular formula: (R1SiO 3 / 2 ) a (MeSiO 3 / 2 ) b (R2MeSiO) c (R3MeSiO) d (Me3SiO 1 / 2 ) e (Me2ViSiO 1 / 2 ) f When R1 includes -N=C=O, R2 is a functional group represented by structural formula I, and R3 is a functional group represented by structural formula II, the bonding strength between the silicone composition and the base polymer can be improved. Compared with the performance of encapsulation materials that do not contain inhibitors of this structural formula, the silicone composition of this application has a high bonding strength and does not affect the transparency of the silicone composition.

[0044] In one embodiment, the second inhibitor comprises an alkynyl compound or a polyvinyl compound.

[0045] The second inhibitor is an alkynyl-containing compound or a polyvinyl compound. The second inhibitor coordinates and complexes with the active center of the platinum-based catalyst. Its alkynyl group can form a stable complex with the platinum in the platinum-based catalyst, changing the electron cloud density and spatial configuration of the platinum-based catalyst, causing the platinum-based catalyst to temporarily lose its activity, thereby preventing the hydrosilylation reaction and increasing its storage time at room temperature.

[0046] In one embodiment, the alkynyl-containing compound includes one or more of 1-ethynyl-1-cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, 3,7,11-trimethyldodecyn-3-ol, 3-methyl-1-pentyn-3-ol, and 2-methyl-3-butyn-2-ol; the polyvinyl compound includes tetramethyltetravinylcyclotetrasiloxane.

[0047] In one embodiment, the base polymer comprises the following components by weight: 80-120 parts of organopolysiloxane resin, 20-40 parts of a second toughening diluent, and 1-20 parts of fumed silica.

[0048] Specifically, the organopolysiloxane resin is any one value or a range of any two values ​​selected from 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 105 parts, 110 parts, 115 parts, or 120 parts; in a preferred embodiment, the organopolysiloxane resin is 80-120 parts.

[0049] Specifically, the second toughening diluent is any one value or a range of any two values ​​selected from 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, or 40 parts; in a preferred embodiment, the second toughening diluent is 25-35 parts.

[0050] Specifically, the fumed silica is any one value or a range of any two values ​​from 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, or 20 parts; in a preferred embodiment, the fumed silica is 5-15 parts.

[0051] Specifically, fumed silica includes one or more of the following: silica modified with hexamethyldiazasilane, silica modified with silicone oil, and silica modified with epoxy groups. When the mass fraction of fumed silica is 1-20 parts, it has a small particle size and a large surface area, and good compatibility with organopolysiloxane resins. In liquid die bond adhesives, it can improve the mechanical properties of silicone compositions and form a three-dimensional network structure through silanol groups, exhibiting reversible thixotropy and preventing overflow of the silicone die bond adhesive after dispensing. When the mass fraction of fumed silica is less than 1 part, it will result in too low thixotropy and overflow after dispensing. When the mass fraction of fumed silica is greater than 20 parts, it will result in too high thixotropy, affecting the wettability of the die bond adhesive on the chip or substrate.

[0052] In one embodiment, the organopolysiloxane resin comprises a vinyl polysiloxane compound, the vinyl polysiloxane compound comprising at least one vinyl group, and the vinyl content in the vinyl polysiloxane compound is 0.05-1.1 mol / 100g.

[0053] Specifically, the vinyl content in the vinyl polysiloxane compounds is 0.05 mol / 100g, 0.1 mol / 100g, 0.15 mol / 100g, 0.2 mol / 100g, 0.25 mol / 100g, 0.3 mol / 100g, 0.35 mol / 100g, 0.4 mol / 100g, 0.45 mol / 100g, 0.5 mol / 100g, 0.55 mol / 100g, 0.6 mol / 100g, 0... The value is any one point or a range of any two points selected from 0.65mol / 100g, 0.7mol / 100g, 0.75mol / 100g, 0.8mol / 100g, 0.85mol / 100g, 0.9mol / 100g, 0.95mol / 100g, 1mol / 100g, 1.05mol / 100g, or 1.1mol / 100g; in a preferred embodiment, the vinyl content in the vinyl polysiloxane compound is 0.3-0.8 mol / 100g.

[0054] In a preferred embodiment, the vinyl polysiloxane compound comprises two or more vinyl groups; after the vinyl polysiloxane compound is mixed with a hydrogen-containing organosilicon compound, it is further cured by heating under the action of a platinum-based catalyst to form a three-dimensional cross-linked network structure. In one embodiment, the vinyl polysiloxane compound includes one or more of MD linear vinyl polysiloxane, MDT branched vinyl polysiloxane, MTQ bulk vinyl polysiloxane, and MQ type vinyl polysiloxane.

[0055] Specifically, the use of the aforementioned vinyl polysiloxane compounds can adjust the viscosity of the silicone composition and balance the hardness and toughness of the cured product.

[0056] In one embodiment, the first toughening diluent comprises a polydimethylsiloxane compound; and / or, The second toughening diluent comprises vinyl silicone oil; The viscosity of the vinyl silicone oil is 50-500 cp.

[0057] Specifically, the viscosity of the vinyl silicone oil is any one value or a range of any two values ​​selected from 50cp, 100cp, 150cp, 200cp, 250cp, 300cp, 350cp, 400cp, 450cp, or 500cp; in a preferred embodiment, the viscosity of the vinyl silicone oil is 50-500cp.

[0058] Specifically, using low-viscosity vinyl silicone oil can reduce the viscosity of silicone die bond, making subsequent processing easier and acting as a diluent in the formulation.

[0059] In one embodiment, the polydimethylsiloxane compound includes one or more of methyl polydimethylsiloxane, vinyl polydimethylsiloxane, hydrogen-containing polydimethylsiloxane, and phenyl polydimethylsiloxane.

[0060] Specifically, the use of the above-mentioned polydimethylsiloxane compounds can improve the flowability of silicone polymers.

[0061] In one embodiment, the hydrogen-containing organosilicon compound includes a hydrogen-containing polysiloxane compound, wherein the viscosity of the hydrogen-containing polysiloxane compound is 1-50 cp and the hydrogen content is 0.6-2 mol / 100g.

[0062] Hydrogen-containing organosilicon compounds are crosslinking agents for organosilicon die bond adhesives. The molecules of hydrogen-containing organosilicon compounds contain organosiloxane polymers with two or more Si-H bonds, which help the base polymer form a three-dimensional crosslinked network after high-temperature reaction.

[0063] Specifically, the viscosity of the hydrogen-containing polysiloxane compound is any one value or a range of any two values ​​selected from 1cp, 5cp, 10cp, 15cp, 20cp, 25cp, 30cp, 35cp, 40cp, 45cp, or 50cp; in a preferred embodiment, the viscosity of the hydrogen-containing polysiloxane compound is 10-40cp.

[0064] When the viscosity of the hydrogen-containing polysiloxane compound is 1-50 cp, it can form a three-dimensional cross-linked network with the silicone polymer, thus achieving an appropriate cross-linking density. When the viscosity of the hydrogen-containing polysiloxane compound is less than 1 cp, its molecular weight is small, and the cross-linking agent is easily volatilized during high-temperature curing. When the viscosity of the hydrogen-containing polysiloxane compound is greater than 50 cp, the hydrogen-containing polysiloxane molecular chain is long, which reduces the cross-linking density of the silicone polymer.

[0065] Specifically, the hydrogen content of the hydrogen-containing polysiloxane compound is any one value or a range of any two values ​​selected from 0.6 mol / 100g, 0.7 mol / 100g, 0.8 mol / 100g, 0.9 mol / 100g, 1 mol / 100g, 1.1 mol / 100g, 1.2 mol / 100g, 1.3 mol / 100g, 1.4 mol / 100g, 1.5 mol / 100g, 1.6 mol / 100g, 1.7 mol / 100g, 1.8 mol / 100g, 1.9 mol / 100g, or 2 mol / 100g; in a preferred embodiment, the hydrogen content of the hydrogen-containing polysiloxane compound is 10-40 cp.

[0066] When the hydrogen content of the hydrogen-containing polysiloxane compound is 0.6-2 mol / 100g, it can form a three-dimensional cross-linked network with silicone polymers, and the hardness of the cured product meets the application requirements. When the hydrogen content of the hydrogen-containing polysiloxane compound is less than 0.6 mol / 100g, the cross-linking density in the polymer system will be too low. When the hydrogen content of the hydrogen-containing polysiloxane compound is greater than 2 mol / 100g, the cross-linking density in the polymer system will be too high, and the volume shrinkage rate during curing will be high.

[0067] In one embodiment, the hydrogen-containing polysiloxane compound includes one or more of the following: MD linear hydrogen-containing polysiloxane, MDT branched hydrogen-containing polysiloxane, MT bulk hydrogen-containing polysiloxane, and MQ type hydrogen-containing polysiloxane.

[0068] Specifically, the use of the aforementioned hydrogen-containing polysiloxane compounds can improve the strength of silicone compositions.

[0069] A second aspect of the present invention provides a method for preparing a silicone composition, comprising the following preparation steps: A silicone composition is formed by mixing a base polymer with a second toughening diluent, a hydrogen-containing organosilicon compound, a platinum-based catalyst, a first inhibitor, and a second inhibitor.

[0070] Specifically, the base polymer, a second toughening diluent, a hydrogen-containing organosilicon compound, a platinum-based catalyst, a first inhibitor, and a second inhibitor are added to a vacuum stirrer and mixed. The reaction temperature is 10-40℃, and the reaction time is 0.5h-6h.

[0071] In one embodiment, the preparation method of the base polymer is as follows: organic polysiloxane resin, second toughening diluent, and fumed silica are mixed in an internal mixer for 3-6 hours to form a uniform base polymer.

[0072] The organic polysiloxane resin, the second toughening diluent, and the fumed silica are mixed in an internal mixer. This ensures that the silica is uniformly dispersed in the heat-curing silicone compound. Furthermore, the chain structure and surface chemical groups of the fumed silica aggregates interact with other components in the silicone to form effective rheological control of the silicone, thus avoiding the occurrence of glue spillage and overflow during the subsequent application of the die-bonding adhesive.

[0073] A third aspect of the present invention provides a die-bonding material, which is composed of the silicone composition described above, or prepared by the method for preparing the silicone composition described above.

[0074] The purpose of this invention is to further improve the performance of silicone die bond adhesives to meet market demands, particularly by providing an LED silicone insulating die bond adhesive with a long operating time and low light decay. This LED die bond adhesive offers a longer operating time. The beneficial effects of the present invention will be further illustrated below with reference to the embodiments.

[0075] To make the inventive objectives, technical solutions, and beneficial effects of this invention clearer, the invention is further described in detail below with reference to embodiments. However, it should be understood that the embodiments of this invention are merely for illustrative purposes and not for limiting the invention, and the embodiments are not limited to those given in the specification. Unless otherwise specified, specific experimental or operational conditions in the embodiments were prepared under conventional conditions or according to the conditions recommended by the material supplier.

[0076] Furthermore, it should be understood that the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, does not preclude the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, unless otherwise stated. It should also be understood that the combined connection relationship between one or more devices / apparatus mentioned in this invention does not preclude the existence of other devices / apparatus before or after the combined devices / apparatus, or the insertion of other devices / apparatus between these explicitly mentioned devices / apparatus, unless otherwise stated. Moreover, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not for limiting the order of the method steps or limiting the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0077] In the following embodiments, the reagents, materials and instruments used, unless otherwise specified, are commercially available or can be obtained through synthesis methods known in the art.

[0078] Table 1. Formulation of silicone compositions Note: The above-mentioned basic polymer includes the following components by weight: 100 parts of organopolysiloxane resin (VMQ resin), 30 parts of second toughening diluent, and 15 parts of hexamethyldiazylsilane modified silica. Example 1 This embodiment illustrates the silicone composition disclosed in this invention; it includes the following operational steps: 100 parts of VMQ resin, 30 parts of the second toughening diluent vinyl silicone oil, and 15 parts of hexamethyldiazylsilane-modified silica are mixed in an internal mixer for 3-6 hours to form a uniform base polymer. As shown in Table 1, the base polymer, first inhibitor, second inhibitor, first toughening diluent, hydrogen-containing organosilicon compound, and platinum-based catalyst were stirred and mixed at 25°C for 3 hours to obtain a silicone composition. The first inhibitor was selected from (R1SiO2). 3 / 2 ) 0.2 (MeSiO 3 / 2 ) 0.1 (R2MeSiO) 0.1 (R3MeSiO) 0.2 (Me3SiO 1 / 2 ) 0.2 (Me2ViSiO 1 / 2 ) 0.2 Furthermore, R1 is -CH2-N=C=O, R2 is the functional group shown in structural formula I, and R3 is the functional group shown in structural formula II. The first inhibitor is obtained by mixing, hydrolyzing, and condensing the corresponding siloxane monomer using conventional methods. The second inhibitor is selected from 1-ethynyl-1-cyclohexanol. The first toughening diluent is selected from vinyl polydimethylsiloxane. The hydrogen-containing organosilicon compound is selected from MD linear hydrogen-containing polysiloxane. The platinum catalyst is selected from Speier platinum catalyst.

[0079] Examples 2-8 Examples 2-8 illustrate the silicone compositions disclosed in this invention, including most of the operational steps in Example 1, except that: The components and contents of the silicone composition shown in Table 1 are used.

[0080] Comparative Examples 1-2 Comparative Examples 1-2 are used to illustrate the silicone compositions disclosed in this invention, including most of the operational steps in Example 1, except that: The components and contents of the silicone composition shown in Table 1 are used.

[0081] Performance testing The silicone compositions prepared in Examples 1-8 were subjected to the following performance tests: 1) Viscosity test At 25℃, the viscosity of the sample was tested using a Brookfield Cap 2000+ cone-plate viscometer according to the instructions. The viscosity change rate was used to represent the storage time at room temperature. The calculation method was (C1-C0) / C0*100%, where C1 is the viscosity of the sample after storage and C0 is the initial viscosity of the sample. 2) Volatile matter test After degassing the obtained composition, 10g was taken and kept at 100℃ for 1 hour, then cured at 150℃ for 3 hours. The mass before and after curing was measured. The volatile content was calculated as (m1-m0) / m0*100%, where C1 is the mass of the sample before curing and C0 is the mass of the test sample after curing. Three sets of data were tested, and the average value was recorded. 3) Hardness After degassing the obtained composition, 10g was taken and kept at 100℃ for 1h, then cured at 150℃ for 3h. The hardness value was measured at three points using a Shore D hardness tester at 25℃ and 60%RH, and the average value was recorded.

[0082] 4) Light transmittance and haze After degassing the obtained silicone composition, 25g was taken and made into a 1mm thick film on a 25cm*25cm polytetrafluoroethylene plate. The film was kept at 100℃ for 1h and then cured at 150℃ for 3h. The transmittance and haze were tested using a WGT-S transmittance haze meter at 25℃ and 60%RH, in accordance with GB T 2410-2008. 5) Push force test: 10×30mil silicon wafers are bonded to 2835 brackets. One bracket is bonded with each type of die bonder (the 2835 bracket specifications are 16×36, a total of 576 brackets). The brackets with the wafers bonded are cured at 150℃ for 3 hours, and the push force value when the chip is pushed away is tested using the LB-8100A tester. The test results are shown in Table 2.

[0083] Table 2 The silicone compositions prepared in Comparative Examples 1 and 2 were subjected to the following performance tests: 1) Viscosity test At 25℃, the viscosity of the sample was tested using a Brookfield Cap 2000+ cone-plate viscometer according to the instructions. The viscosity change rate was used to represent the storage time at room temperature. The calculation method was (C1-C0) / C0*100%, where C1 is the viscosity of the sample after storage and C0 is the initial viscosity of the sample. 2) Push force test: 10×30mil silicon wafers were bonded to 2835 brackets. One bracket was bonded with each type of die bonder (the 2835 bracket specifications are 16×36, a total of 576 brackets). The brackets with the wafers bonded were cured at 150℃ for 3 hours, and the push force value when the chip was pushed away was tested using the LB-8100A tester. The test results are shown in Table 3.

[0084] Table 3 As can be seen from the comparison of the above embodiments and comparative examples, the silicone composition provided by the present invention has good room temperature storage performance and can maintain low viscosity and operability during long-term storage. At the same time, the silicone composition provided by the present invention has excellent performance in terms of hardness, light transmittance and adhesive strength.

[0085] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A silicone composition, characterized in that: The composition comprises the following components by weight: 80-120 parts of base polymer, 0.01-9 parts of first inhibitor, 0.01-3 parts of second inhibitor, 10-30 parts of first toughening diluent, 10-40 parts of hydrogen-containing organosilicon compound, and 0.01-1 parts of platinum-based catalyst; The first inhibitor is a thickening inhibitor, and the structural formula of the thickening inhibitor is: R-(X)n; wherein, R is an organopolysiloxane host, X is one or both of -C=N or -N=C=O, and R contains at least one vinyl group.

2. The silicone composition according to claim 1, characterized in that: The thickening inhibitor has the following molecular formula: (R1SiO) 3 / 2 ) a (MeSiO 3 / 2 ) b (R2MeSiO) c (R3MeSiO) d (Me3SiO 1 / 2 ) e (Me2ViSiO 1 / 2 ) f ; Where a, b, c, d, e, and f satisfy the following relations: a > 0, b > 0, c > 0, d > 0, e > 0, f > 0 respectively; R1 includes -N=C=O bonds; R2 is the functional group shown in structural formula I: ； R3 is the functional group shown in structural formula II: 。 3. The silicone composition according to claim 1, characterized in that: The second inhibitor includes alkynyl compounds or polyvinyl compounds.

4. The silicone composition according to claim 3, characterized in that: The alkyne-containing compounds include one or more of 1-ethynyl-1-cyclohexanol, 3,5-dimethyl-1-hexyn-3-ol, 3,7,11-trimethyldodecyn-3-ol, 3-methyl-1-pentyn-3-ol, and 2-methyl-3-butyn-2-ol; the polyvinyl compounds include tetramethyltetravinylcyclotetrasiloxane.

5. The silicone composition according to claim 1, characterized in that: The base polymer comprises the following components by weight: 80-120 parts of organopolysiloxane resin, 20-40 parts of second toughening diluent, and 1-20 parts of fumed silica.

6. The silicone composition according to claim 5, characterized in that: The organopolysiloxane resin includes vinyl polysiloxane compounds, wherein the vinyl polysiloxane compounds include at least one vinyl group, and the vinyl content in the vinyl polysiloxane compounds is 0.05-1.1 mol / 100g.

7. The silicone composition according to claim 6, characterized in that: The vinyl polysiloxane compounds include one or more of the following: MD linear vinyl polysiloxane, MDT branched vinyl polysiloxane, MTQ bulk vinyl polysiloxane, and MQ type vinyl polysiloxane.

8. The silicone composition according to claim 5, characterized in that: The first toughening diluent comprises a polydimethylsiloxane compound; and / or, The second toughening diluent comprises vinyl silicone oil; The viscosity of the vinyl silicone oil is 50-500 cp.

9. The silicone composition according to claim 8, characterized in that: The polydimethylsiloxane compounds include one or more of methyl polydimethylsiloxane, vinyl polydimethylsiloxane, hydrogen-containing polydimethylsiloxane, and phenyl polydimethylsiloxane.

10. The silicone composition according to claim 1, characterized in that: The hydrogen-containing organosilicon compound includes hydrogen-containing polysiloxane compounds, wherein the viscosity of the hydrogen-containing polysiloxane compound is 1-50 cp and the hydrogen content is 0.6-2 mol / 100g.

11. The silicone composition according to claim 10, characterized in that: The hydrogen-containing polysiloxane compounds include one or more of the following: MD linear hydrogen-containing polysiloxane, MDT branched hydrogen-containing polysiloxane, MT bulk hydrogen-containing polysiloxane, and MQ type hydrogen-containing polysiloxane.

12. The method for preparing the silicone composition according to any one of claims 1-11, characterized in that: The preparation steps include the following: A silicone composition is formed by mixing a base polymer with a second toughening diluent, a hydrogen-containing organosilicon compound, a platinum-based catalyst, a first inhibitor, and a second inhibitor.

13. The method for preparing the silicone composition according to claim 12, characterized in that: The preparation method of the base polymer is as follows: organic polysiloxane resin, second toughening diluent, and fumed silica are mixed in an internal mixer for 3-6 hours to form a uniform base polymer.

14. A crystal-bonding material, characterized in that: It is composed of the silicone composition according to any one of claims 1-11, or prepared by the method of preparing the silicone composition according to any one of claims 12-13.

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