阅读说明：本技术 单封端丙酰氧基有机硅树脂及其制备方法、包含该有机硅树脂的导电胶粘剂及其制备方法 (Single-end-capped propionyloxy organic silicon resin, preparation method thereof, conductive adhesive containing organic silicon resin and preparation method thereof ) 是由 张建平 于 2020-05-06 设计创作，主要内容包括：本发明公开了一种单封端丙酰氧基有机硅树脂及其制备方法、包含该有机硅树脂的导电胶粘剂及其制备方法,所述单封端丙酰氧基有机硅树脂的结构式如式(I),所述导电胶粘剂,包括10～30份所述单封端丙酰氧基有机硅树脂,还包括如下重量份数的原料：热引发剂0.5～5份、热塑性粉末填料1～5份、改性银粉60～80份、溶剂1～10份、稳定剂0.1～1份；其中,所述单封端丙酰氧基有机硅树脂的重量份数为10～30份。本发明中的导电胶粘剂具有优异的固化物伸长率、粘接强度、导电性能、柔韧性及抗跌落性,可广泛应用在电子行业中。(The invention discloses a single-end-capped propionyloxy organic silicon resin and a preparation method thereof, and a conductive adhesive containing the organic silicon resin and a preparation method thereof, wherein the structural formula of the single-end-capped propionyloxy organic silicon resin is shown as a formula (I), and the conductive adhesive comprises 10-30 parts of the single-end-capped propionyloxy organic silicon resin and also comprises the following raw materials in parts by weight: 0.5-5 parts of thermal initiator, 1-5 parts of thermoplastic powder filler, 60-80 parts of modified silver powder, 1-10 parts of solvent and 0.1-1 part of stabilizer; wherein the weight part of the singly-terminated propionyloxy organic silicon resin is 10-30 parts. The conductive adhesive disclosed by the invention has excellent elongation, bonding strength, conductivity, flexibility and drop resistance of a cured product, and can be widely applied to the electronic industry.)

1. A singly-terminated propionyloxy silicone resin, wherein the structure formula of the singly-terminated propionyloxy silicone resin is shown as formula (I):

wherein R is₁Is H or CH₃；

R₂Is CH₃Or CH₂CH₂CH₂；

R₃Is CH₃、CH₂CH₃、CH₂CH₂CH₃Any one of the above;

R₄is CH₃、CH₂CH₃、CH₂CH₂CH₃Any one of the above;

n is an integer of 200 to 20000.

2. A method of preparing the single-ended propionyloxy silicone resin of claim 1, comprising the steps of: reacting hydroxyl-containing silane and vinyl-containing or acryloyloxy-containing silane under the action of a catalyst, adding benzenediol to terminate the reaction after the viscosity of the system reaches a target value, and cleaning and distilling the obtained reaction product to obtain the single-end-capped propionyloxy organic silicon resin;

wherein the reaction temperature of the hydroxyl-containing silane and the vinyl-containing or acryloxy-containing silane in the reaction under the action of the catalyst is 100-130 ℃.

3. A conductive adhesive comprising the single-ended propionyloxy silicone resin of claim 1, further comprising the following raw materials in parts by weight: 0.5-5 parts of thermal initiator, 1-5 parts of thermoplastic powder filler, 60-80 parts of modified silver powder and 1-10 parts of solvent; wherein the weight part of the singly-terminated propionyloxy organic silicon resin is 10-30 parts.

4. The conductive adhesive according to claim 3, wherein the modified silver powder is prepared by the following method: adding silver powder into a NaOH solution, stirring at a high speed for reaction for 1.5-4.5 hours, standing for 8-15 hours, washing with pure water for 3 times, washing with alcohol for 2 times, drying and sieving to obtain modified silver powder;

wherein the mass fraction of the NaOH solution is 1%;

wherein the weight ratio of the silver powder to the NaOH solution is 1: 50;

wherein the stirring reaction temperature is less than 50 ℃.

5. The conductive adhesive according to claim 4, wherein the silver powder is selected from one or two of silver powder having a designation of TC-505 and silver powder having a designation of TCG-1, manufactured by Germany and Japan.

6. The conductive adhesive according to claim 3, wherein the thermal initiator is an azo-based thermal initiator or a peroxide-based thermal initiator.

7. The conductive adhesive according to claim 6, wherein the thermal initiator is selected from any one of benzoyl peroxide, t-butyl peroxybenzoate, diisopropylbenzene hydroperoxide, and azobisisobutyronitrile.

8. A conductive adhesive as in claim 3 wherein said thermoplastic powder filler is selected from any one or more of polyimide powder, polyurethane powder, polyester powder, acrylate powder, nano silica powder; the solvent is selected from any one of alkane solvents, methanol, No. 100 solvent naphtha and No. 80 solvent naphtha.

9. A method of preparing a conductive adhesive as claimed in any one of claims 3 to 8 comprising the steps of:

s1, weighing the singly-terminated propionyloxy organic silicon resin, the thermal initiator, the thermoplastic powder filler, the modified silver powder and the solvent according to the formula ratio;

s2, sequentially adding the singly-terminated propionyloxy organic silicon resin, the thermoplastic powder filler, the modified silver powder and part of the solvent weighed in the step S1 into a stirrer, stirring and reacting for 1.5-3.5 hours, and then putting the stirred material into a grinder to grind and disperse to obtain a mixed material A;

s3, continuously grinding and dispersing the mixed material A obtained in the step S2 through a grinder to obtain a mixed material B;

and S4, dissolving the thermal initiator weighed in the step S1 in the residual solvent, adding the dissolved thermal initiator into the mixed material B, grinding and dispersing the mixture by a grinder, adding the mixture into a stirrer, stirring the mixture to adjust the viscosity to a target value, filtering the mixture, and defoaming the mixture in vacuum to obtain the conductive adhesive.

10. The method for preparing a conductive adhesive according to claim 9, wherein in step S2, the stirred material is put into a three-roll grinder to grind and disperse for 2 times to obtain a mixed material a; wherein, the grinding dispersion time is 60 minutes each time, and the distance between two adjacent rollers is 50 μm;

in the step S3, the mixture a is ground and dispersed for 2 times by a three-roll grinder to obtain a mixture B; wherein, the grinding dispersion time is 60 minutes each time, and the distance between two adjacent rollers is 25 μm;

and in the step S4, dissolving the thermal initiator weighed in the step S1 in the residual solvent, adding the dissolved thermal initiator into the mixed material B, grinding and dispersing for 2 times by using a superfine three-roll grinder, adding the mixture into a stirrer, stirring and adjusting the viscosity to a target value, filtering by using a stainless steel mesh of 450 meshes, and defoaming in vacuum to obtain the conductive adhesive.

Technical Field

The invention relates to the technical field of conductive adhesives, in particular to a single-end-capped propionyloxy organic silicon resin and a preparation method thereof, and a conductive adhesive containing the organic silicon resin and a preparation method thereof.

Background

Disclosure of Invention

The invention aims to overcome the defects and provides a single-end-capped propionyloxy organic silicon resin and a preparation method thereof, and a conductive adhesive containing the organic silicon resin and a preparation method thereof; the single-end-capped propionyloxy organic silicon resin is added into the conductive adhesive to improve the moisture resistance, heat resistance and high and low temperature resistance of the conductive adhesive, meanwhile, the conductive adhesive has excellent elongation, bonding strength, conductivity, flexibility and drop resistance of a cured product, can be widely applied to the electronic industry, has low requirement on the surface cleanliness of an attached substrate when in use, can adapt to substrates which cannot be made of materials, solves the problems that the addition type organic silicon conductive adhesive has strict requirement on bonding materials, and leads to poor curing caused by platinum catalyst poisoning when organic phosphorus, sulfur, amine, organic tin, moisture and other substances are attached to the surface of an attached substance, and also solves the problems that the existing addition type organic silicon conductive adhesive can be degummed or does not start oscillation when being used for SMD crystalline silicon packaging.

In order to achieve the above object, the present invention provides in a first aspect a single-ended propionyloxy silicone resin, the structural formula of which is shown in formula (I):

wherein R is₁Is H or CH₃；

R₂Is CH₃Or CH₂CH₂CH₂；

R₃Is CH₃、CH₂CH₃、CH₂CH₂CH₃Any one of the above;

R₄is CH₃、CH₂CH₃、CH₂CH₂CH₃Any one of the above;

n is an integer of 200 to 20000.

The invention provides a preparation method of the single-end-capped propionyloxy organic silicon resin, which comprises the following steps: reacting hydroxyl-containing silane and vinyl-containing or acryloyloxy-containing silane under the action of a catalyst, adding benzenediol to terminate the reaction after the viscosity of the system reaches a target value, and cleaning and distilling the obtained reaction product to obtain the single-end-capped propionyloxy organic silicon resin, wherein the reaction formula is as follows:

further, the catalyst is an organotin catalyst.

Preferably, the catalyst is selected from dibutyltin dilaurate or stannous octoate.

Further, the molar ratio of the hydroxyl-containing silane to the vinyl-containing or acryloxy-containing silane to the catalyst to the benzenediol is 10: 10: 0.1-1: 0.1 to 1.

Preferably, the reaction temperature of the hydroxyl-containing silane and the vinyl-containing or acryloxy-containing silane in the reaction under the action of the catalyst is 100-130 ℃.

Preferably, the preparation method of the single-end-capped propionyloxy organic silicon resin comprises the following steps: reacting hydroxyl-containing silane and vinyl-containing or acryloyloxy-containing silane under the action of a catalyst, adding benzenediol to terminate the reaction when the system viscosity reaches 1000-50000 mPa.S, and cleaning and distilling the obtained reaction product to obtain the single-end-capped propionyloxy organic silicon resin.

Preferably, in the above method for preparing a single-ended propionyloxy silicone resin, the reaction product is washed with alcohol or isopropanol.

The third aspect of the invention provides a conductive adhesive, which comprises the single-end-capped propionyloxy organic silicon resin and also comprises the following raw materials in parts by weight: 0.5-5 parts of thermal initiator, 1-5 parts of thermoplastic powder filler, 60-80 parts of modified silver powder, 1-10 parts of solvent and 0.1-1 part of stabilizer; wherein the weight part of the singly-terminated propionyloxy organic silicon resin is 10-30 parts.

Further, the modified silver powder is prepared by the following method: adding silver powder into a NaOH solution, stirring at a high speed for reaction for 1.5-4.5 hours, standing for 8-15 hours, washing with pure water for 3 times, washing with alcohol for 2 times, drying and sieving to obtain modified silver powder;

wherein the stirring speed is 3000 r/min; wherein the number of the sieving meshes is 300-500 meshes.

Wherein the mass fraction of the NaOH solution is 1%;

wherein the weight ratio of the silver powder to the NaOH solution is 1: 50;

wherein the stirring reaction temperature is less than 50 ℃.

Preferably, the silver powder is selected from any one or two of silver powder having a trade name of TC-505 and silver powder having a trade name of TCG-1 manufactured by Germany and Japan.

Preferably, the thermal initiator is an azo-based thermal initiator or a peroxide-based thermal initiator.

Further preferably, the thermal initiator is selected from any one of benzoyl peroxide, tert-butyl peroxybenzoate, diisopropylbenzene hydroperoxide, and azobisisobutyronitrile.

Preferably, the thermoplastic powder filler is selected from any one or more of polyimide powder, polyurethane powder, polyester powder, acrylate powder and nano silicon dioxide powder; the solvent is selected from any one of alkane solvents, methanol, No. 100 solvent naphtha and No. 80 solvent naphtha.

The third aspect of the invention provides a preparation method of a conductive adhesive, which comprises the following steps:

s1, weighing the singly-terminated propionyloxy organic silicon resin, the thermal initiator, the thermoplastic powder filler, the modified silver powder and the solvent according to the formula ratio;

s2, sequentially adding the singly-terminated propionyloxy organic silicon resin, the thermoplastic powder filler, the modified silver powder and part of the solvent weighed in the step S1 into a stirrer, stirring and reacting for 1.5-3.5 hours, and then putting the stirred material into a grinder to grind and disperse to obtain a mixed material A;

s3, continuously grinding and dispersing the mixed material A obtained in the step S2 through a grinder to obtain a mixed material B;

and S4, dissolving the thermal initiator weighed in the step S1 in the residual solvent, adding the dissolved thermal initiator into the mixed material B, grinding and dispersing the mixture by a grinder, adding the mixture into a stirrer, stirring the mixture to adjust the viscosity to a target value, filtering the mixture, and defoaming the mixture in vacuum to obtain the conductive adhesive.

Preferably, the solvent added in step S2 is 60% of the total solvent weighed in step S1 by mass

Further, in the step S2, the stirred material is put into a three-roll grinder to be ground and dispersed for 2 times to obtain a mixed material a; wherein, the grinding dispersion time is 60 minutes each time, and the distance between two adjacent rollers is 50 μm;

in the step S3, the mixture a is ground and dispersed for 2 times by a three-roll grinder to obtain a mixture B; wherein, the grinding dispersion time is 60 minutes each time, and the distance between two adjacent rollers is 25 μm;

and in the step S4, dissolving the thermal initiator weighed in the step S1 in the residual solvent, adding the solution into the mixed material B, grinding and dispersing for 2 times by using a superfine three-roll grinder, adding the mixture into a stirrer, stirring and adjusting the viscosity to 10000-20000 mPa.S, filtering the mixture by using a 450-mesh stainless steel net, and defoaming the mixture in vacuum to obtain the conductive adhesive.

Compared with the prior art, the invention has the beneficial effects that:

1. the single-end-capped propionyloxy organic silicon resin is used for preparing the conductive adhesive.

2. The conductive adhesive has excellent elongation of a cured product, bonding strength, conductivity, flexibility and drop resistance, can be widely applied to the electronic industry, has low requirement on the surface cleanliness of an attached substrate when in use, can adapt to the substrate which cannot be made of materials, solves the problem that the addition type organic silicon conductive adhesive has harsh requirement on the bonding material, leads platinum catalyst poisoning to cause poor curing if organic phosphorus, sulfur, amine, organic tin, moisture and other substances are attached to the surface of an attached substance, and also solves the problem that the existing addition type organic silicon conductive adhesive can be degummed or does not start up the crystal oscillator when in stronger vibration when being used for SMD (surface mounted device) crystal silicon packaging.

3. The conductive adhesive is suitable for packaging SMD crystal oscillators, and is particularly suitable for small-size SMD crystal oscillators with the size specification of 2mm × 1.6.6 mm and the size specification of 1.6mm × 1.2.2 mm.

4. The conductive adhesive has low requirements on the adhesive and curing equipment in the curing process and is convenient to use.

5. The preparation method of the conductive adhesive has simple process, can be completed by using the existing general equipment, and is convenient for wide popularization and application.

Detailed Description

The present invention will be further described with reference to specific embodiments in order to make the technical means, inventive features, objectives and effects of the invention easy to understand.