阅读说明：本技术 高温加成型有机硅电磁屏蔽胶及其制备方法 (High-temperature addition type organic silicon electromagnetic shielding adhesive and preparation method thereof ) 是由 陈永隆 刘光华 黄琪 罗玉文 陈建军 黄恒超 缪明松 于 2021-08-31 设计创作，主要内容包括：本发明公开了一种高温加成型有机硅电磁屏蔽胶及其制备方法,所述电磁屏蔽胶各组分的比例为：镍包碳纤维200-400份,乙烯基硅油80-100份,含氢硅油5-20份,白炭黑30-80份,扩链剂0.5-2份,增粘剂1-5份,抑制剂0.1-0.3份,铂金催化剂0.1-0.3份,稀释剂10-30份。本发明加入镍包碳纤维到体系之中,可以对体系进行补强,同时提供良好的导电性和电磁屏蔽性。在点胶固化后体积电阻小于40mΩ·cm,屏蔽效能达到120dB以上,拉伸强度达到4.0MPa,撕裂强度大于20N/mm,在156℃热老化48H体积电阻率仅仅上升初始的12.5％左右,电磁屏蔽效果可保持为初始的90％左右。所述电磁屏蔽胶具有低成本、高导电性、力学性能优异、密封性好、电磁屏蔽效果稳定的特点。(The invention discloses a high-temperature addition type organosilicon electromagnetic shielding adhesive and a preparation method thereof, wherein the electromagnetic shielding adhesive comprises the following components in proportion: 400 parts of nickel-coated carbon fiber 200-100 parts of vinyl silicone oil, 5-20 parts of hydrogen-containing silicone oil, 30-80 parts of white carbon black, 0.5-2 parts of chain extender, 1-5 parts of tackifier, 0.1-0.3 part of inhibitor, 0.1-0.3 part of platinum catalyst and 10-30 parts of diluent. According to the invention, the nickel-coated carbon fiber is added into the system, so that the system can be reinforced, and good conductivity and electromagnetic shielding property are provided. After the spot gluing and curing, the volume resistance is less than 40m omega cm, the shielding effectiveness reaches more than 120dB, the tensile strength reaches 4.0MPa, the tearing strength is more than 20N/mm, the volume resistivity is only increased by about 12.5 percent of the initial volume resistivity after the spot gluing and curing, and the electromagnetic shielding effect can be kept to about 90 percent of the initial volume resistivity after the spot gluing and curing. The electromagnetic shielding adhesive has the characteristics of low cost, high conductivity, excellent mechanical property, good sealing property and stable electromagnetic shielding effect.)

1. The high-temperature addition type organosilicon electromagnetic shielding adhesive comprises a conductive filler and is characterized in that the conductive filler is one or a combination of more of nickel-coated carbon fiber, nickel-coated copper powder, nickel-coated silver powder, nickel-coated graphite powder, nickel powder, silver-coated copper powder and silver-coated aluminum powder.

2. The high-temperature addition type silicone electromagnetic shielding adhesive according to claim 1, comprising the following components: 200-400 parts of conductive filler, 80-100 parts of vinyl silicone oil, 5-20 parts of hydrogen-containing silicone oil, 30-80 parts of white carbon black, 0.5-2 parts of chain extender, 1-5 parts of tackifier, 0.1-0.3 part of inhibitor, 0.1-0.3 part of platinum catalyst and 10-30 parts of diluent.

3. The high temperature addition silicone electromagnetic shield glue of claim 2, wherein the vinyl silicone oil is a combination of one or more of a terminal vinyl silicone oil, a side vinyl silicone oil, a vinyl terminated oligosiloxane.

4. The high-temperature addition type silicone electromagnetic shielding adhesive according to claim 2, wherein the hydrogen-containing silicone oil is one of hydrogen-containing silicone oil, end side hydrogen silicone oil or a combination of two.

5. The high-temperature addition type organosilicon electromagnetic shielding adhesive according to claim 2, wherein the white carbon black is one or a combination of more of precipitated white carbon black, hydrophilic white carbon black and hydrophobic white carbon black.

6. The high temperature addition silicone electromagnetic shield gel of claim 2, wherein the inhibitor is one or a combination of more of 1-ethyne-1-cyclohexanol, 3-methyl-1-butyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol, 3, 6-dimethyl-1-heptyn-3-ol.

7. The high temperature addition silicone electromagnetic shield according to claim 2, wherein the solvent is ethanol, acetone, kerosene, octamethyltrisiloxane, dimethyl carbonate, or decamethyltetrasiloxane.

8. A preparation method of a high-temperature addition type organic silicon electromagnetic shielding adhesive comprises the preparation of nickel-coated carbon fibers, and is characterized in that the preparation method of the nickel-coated carbon fibers comprises the following steps:

(1) cutting carbon fibers, washing the carbon fibers with deionized water for multiple times, then soaking the carbon fibers in 0.1mol/L of coupling agent solution containing amino for 30-45min, heating the carbon fibers at 110 ℃ for 30-45min, and repeating the steps for multiple times to obtain amino modified carbon fibers;

(2) placing the amino modified carbon fiber in nickel sulfur hexahydrate (NiCl)₂·6H₂O) for 15-30min, and then adding NaBH₄Soaking in the solution for 15-30min, and washing with deionized water for multiple times;

(3) and (3) putting the treated amino modified carbon fiber into a chemical nickel plating solution, reacting for 45-90min, repeatedly washing with deionized water for many times, and then putting into a 50 ℃ oven to bake for 45-90min to obtain the nickel-coated carbon fiber.

Technical Field

The invention relates to the technical field of organic silicon viscose, in particular to a low-cost high-temperature addition type organic silicon electromagnetic shielding glue and a preparation method thereof.

Background

The electromagnetic shielding problem of electronic and electric appliances is always a great problem affecting the long-term stable use of electronic instruments and equipment. The electromagnetic shielding glue used by various electrical appliances at present mainly plays roles of bonding, sealing protection and electromagnetic shielding on components, wherein metal powder such as silver powder, copper powder and the like is usually mixed in the electromagnetic shielding glue for realizing the electromagnetic shielding effect, the price is expensive, other mechanical properties such as the sealing property, the bonding strength and the like of the electromagnetic shielding glue are gradually reduced along with the prolonging of time, the electromagnetic shielding effect is also reduced, the performance of electronic products is influenced, and the electromagnetic shielding glue can cause serious harm to human beings and other organisms. Therefore, there is a need in the related art for an electromagnetic shielding adhesive with low cost, high conductivity, excellent mechanical properties, good sealing performance, good electromagnetic shielding effect, and stability.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a low-cost high-temperature addition type organosilicon electromagnetic shielding glue and a preparation method thereof. The electromagnetic shielding glue has the characteristics of low cost, high conductivity, excellent mechanical property, good sealing property and stable electromagnetic shielding effect, and can solve the problems of unstable sealing property, bonding strength and electromagnetic shielding effect of the existing electromagnetic shielding glue.

The high-temperature addition type organic silicon electromagnetic shielding adhesive comprises the following components:

the conductive filler adopts nickel-coated carbon fiber, nickel-coated copper powder, nickel-coated silver powder, nickel-coated graphite powder, nickel powder, silver-coated copper powder or silver-coated aluminum powder to replace the traditional metal powder such as silver powder, copper powder and the like, and the electromagnetic shielding adhesive has the following components in preferred proportion: 400 parts of conductive filler 200, 80-100 parts of vinyl silicone oil, 5-20 parts of hydrogen-containing silicone oil, 30-80 parts of white carbon black, 0.5-2 parts of chain extender, 1-5 parts of tackifier, 0.1-0.3 part of inhibitor, 0.1-0.3 part of platinum catalyst and 10-30 parts of diluent. The above parts are all parts by weight, and the conductive filler can also adopt a combination of a plurality of different powders, wherein the nickel powder can be selected from one or a combination of a plurality of powders with the particle size of 50 μm, 100 μm and 150 μm in view of cost.

The vinyl silicone oil is preferably one or more of terminal vinyl silicone oil, side vinyl silicone oil and vinyl-terminated oligosiloxane.

The hydrogen-containing silicone oil is preferably one or two of hydrogen-containing silicone oil and end-side hydrogen silicone oil, and the viscosity of the hydrogen-containing silicone oil is 100-2000 mPas.

The white carbon black can be one or more of precipitation white carbon black, hydrophilic white carbon black and hydrophobic white carbon black.

The inhibitor is preferably one or more of 1-acetylene-1-cyclohexanol, 3-methyl-1-butyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol and 3, 6-dimethyl-1-heptyn-3-ol.

The solvent may be ethanol, acetone, kerosene, octamethyltrisiloxane, dimethyl carbonate, or decamethyltetrasiloxane.

The platinum content in the platinum catalyst is 3000-5000 ppm.

The preparation method of the high-temperature addition type organic silicon electromagnetic shielding glue comprises the following steps:

firstly, preparing nickel-coated carbon fibers:

(1) cutting the carbon fiber, washing with deionized water for many times, then soaking in 0.1mol/L coupling agent solution containing amino for 30-45min, heating at 110 ℃ for 30-45min, and repeating for many times to obtain the amino modified carbon fiber.

(2) Placing the amino modified carbon fiber in nickel sulfur hexahydrate (NiCl)₂·6H₂O) for 15-30min, and then adding sodium borohydride (NaBH)₄) SolutionSoaking in the solution for 15-30min, and washing with deionized water for several times.

(3) And (3) putting the treated amino modified carbon fiber into a chemical nickel plating solution, reacting for 45-90min, repeatedly washing with deionized water for many times, and then putting into a 50 ℃ oven to bake for 45-90min to obtain the nickel-coated carbon fiber. The chemical nickel plating solution can adopt the following components:

and the other conductive fillers such as nickel-coated copper powder, nickel-coated silver powder, nickel-coated graphite powder, nickel powder, silver-coated copper powder or silver-coated aluminum powder and the like can be prepared by adopting the existing process or purchased directly on the market.

Detailed Description

The present invention will be described in detail below with reference to specific examples.

The first embodiment is as follows:

step 1: 60 parts by weight of a vinyl silicone oil having a viscosity of 1 ten thousand, 40 parts by weight of a vinyl silicone oil having a viscosity of 2 ten thousand, 1.5 parts by weight of a silazane, and 0.5 part by weight of distilled water 1 were put into a kneader and stirred for 15 minutes. And adding 50 parts of fumed silica into the kneader in batches, stirring for 1 hour, heating to 150 ℃, and continuing stirring in vacuum for 3 hours to obtain a semi-finished product masterbatch.

Step 2:

(1) firstly, cutting 100 parts of carbon fiber by using a composite material cutting machine, washing the carbon fiber by using deionized water for 3 times, then soaking the carbon fiber in 0.1mol/L KH550 and other amino-containing coupling agent solutions for 20min, finally heating the carbon fiber at 110 ℃ for 20min, and repeating the steps for 3 times to obtain the amino-modified carbon fiber.

(2) Amino modified carbon fiber is added into nickel sulfur hexahydrate (NiCl)₂·6H₂O) for 15min, and then adding NaBH₄Soaking in the solution for 15min, and washing with deionized water for 3 times.

(3) And (3) putting the treated amino modified carbon fiber into a chemical nickel plating solution, reacting for 15min, repeatedly washing for 3 times by using deionized water, and then putting into a 50 ℃ oven to bake for 30min to obtain the nickel-coated carbon fiber.

And step 3: taking 100 parts of the semi-finished product master batch, 10 parts of hydrogen-containing silicone oil with the average hydrogen content of 0.3%, 0.6 part of 4000ppm platinum catalyst, 0.06 part of 1-acetylene-1-cyclohexanol, 20 parts of nickel-coated carbon fiber, 180 parts of 50 mu m nickel powder and 20 parts of octamethyltrisiloxane, placing the mixture in a dispersion machine (the rotating speed is 100 revolutions per minute) and stirring the mixture for 10 minutes to prepare the high-temperature addition type organic silicon electromagnetic shielding adhesive.

Example two:

step 1: 60 parts of vinyl silicone oil having a viscosity of 1 ten thousand, 40 parts of vinyl silicone oil having a viscosity of 5 ten thousand, 1.5 parts of silazane and 0.5 part of distilled water 1 were added to a kneader and stirred for 15 minutes. And adding 40 parts of fumed silica into the kneader in batches, stirring for 1 hour, heating to 150 ℃, and continuing stirring in vacuum for 3 hours to obtain a semi-finished product masterbatch.

Step 2:

(1) firstly, cutting 100 parts of carbon fiber by using a composite material cutting machine, washing the carbon fiber by using deionized water for 3 times, then soaking the carbon fiber in 0.1mol/L KH550 and other amino-containing coupling agent solutions for 30min, finally heating the carbon fiber at 110 ℃ for 30min, and repeating the steps for 3 times to obtain the amino-modified carbon fiber.

(2) Putting amino modified carbon fiber into nickel sulfur hexahydrate (NiCl)₂·6H₂O) for 30min, and then adding NaBH₄Soaking in the solution for 30min, and washing with deionized water for 3 times.

(3) And (3) putting the treated amino modified carbon fiber into a chemical nickel plating solution, reacting for 60min, repeatedly washing for 3 times by using deionized water, and then putting into a 50 ℃ oven to bake for 60min to obtain the nickel-coated carbon fiber.

And step 3: taking 100 parts of the semi-finished product master batch, 9 parts of hydrogen-containing silicone oil with the average hydrogen content of 0.61%, 0.5 part of 4000ppm platinum catalyst, 0.05 part of 3-methyl-1-butyne-3-ol, 30 parts of nickel-coated carbon fiber, 170 parts of 100 mu m nickel powder and 25 parts of decamethyltetrasiloxane, placing the mixture in a dispersion machine (the rotating speed is 100r), and stirring for 10min to prepare the high-temperature addition type organic silicon electromagnetic shielding adhesive.

Example three:

step 1: 100 parts of vinyl silicone oil having a viscosity of 1 ten thousand, 1.5 parts of silazane, and 0.5 part of distilled water were put into a kneader and stirred for 30 minutes. And adding 30 parts of white carbon black into the kneader in batches, stirring for 2 hours, heating to 150 ℃, and continuing to stir in vacuum for 3 hours to obtain a semi-finished product masterbatch.

Step 2:

(1) firstly, cutting 100 parts of carbon fiber by using a composite material cutting machine, washing with deionized water for 3 times, then soaking in 0.1mol/L KH550 and other amino-containing coupling agent solutions for 45min, finally heating at 110 ℃ for 45min, and repeating for 3 times to obtain the amino-modified carbon fiber.

(2) Putting amino modified carbon fiber into nickel sulfur hexahydrate (NiCl)₂·6H₂O) soaking for 30min, and adding NaBH₄Soaking in the solution for 30min, and washing with deionized water for 3 times.

(3) And (3) putting the treated carbon fiber into a chemical nickel plating solution, reacting for 90min, repeatedly washing for 3 times by using deionized water, and then putting into a 50 ℃ oven to bake for 90min to obtain the nickel-coated carbon fiber.

And step 3: taking 100 parts of the semi-finished product master batch, 8 parts of hydrogen-containing silicone oil with average hydrogen content of 1.1%, 0.4 part of 4000ppm platinum catalyst, 0.04 part of 3, 5-dimethyl-1-hexyne-3-alcohol, 30 parts of nickel-coated carbon fiber, 170 parts of 100 mu m nickel powder and 30 parts of kerosene, placing the mixture in a dispersion machine (the rotating speed is 100r), and stirring for 10min to prepare the high-temperature addition type organic silicon electromagnetic shielding adhesive.

Example four:

step 1: 100 parts of vinyl silicone oil having a viscosity of 2 ten thousand, 1.5 parts of silazane, and 0.5 part of distilled water were put into a kneader and stirred for 30 minutes. And adding 30 parts of white carbon black into the kneader in batches, stirring for 2 hours, heating to 150 ℃, and continuing to stir in vacuum for 3 hours to obtain a semi-finished product masterbatch.

Step 2:

(1) firstly, cutting 100 parts of carbon fiber by using a composite material cutting machine, washing with deionized water for 3 times, then soaking in 0.1mol/L KH550 and other amino-containing coupling agent solutions for 45min, finally heating at 110 ℃ for 45min, and repeating for 3 times to obtain the amino-modified carbon fiber.

(2) Putting amino modified carbon fiber into nickel sulfur hexahydrate (NiCl)₂·6H₂O) soaking for 30min, and adding NaBH₄Soaking in the solution for 30min, and washing with deionized water for 3 times.

(3) And (3) putting the treated carbon fiber into a chemical nickel plating solution, reacting for 90min, repeatedly washing for 3 times by using deionized water, and then putting into a 50 ℃ oven to bake for 90min to obtain the nickel-coated carbon fiber.

And step 3: taking 100 parts of the semi-finished product master batch, 7 parts of hydrogen-containing silicone oil with average hydrogen content of 1.1%, 0.4 part of 4000ppm platinum catalyst, 0.04 part of 3, 6-dimethyl-1-heptyne-3-alcohol, 30 parts of nickel-coated carbon fiber, 170 parts of 100 mu m nickel-coated silver powder and 30 parts of kerosene, and placing the mixture in a dispersion machine (the rotating speed is 100r) to stir for 10min to prepare the high-temperature addition type organic silicon electromagnetic shielding adhesive.

Example five:

step 1: 100 parts of vinyl silicone oil with the viscosity of 2 ten thousand, 1.5 parts of silazane and 0.5 part of distilled water are added into a kneader and stirred for 30 minutes; and adding 30 parts of white carbon black into the kneader in batches, stirring for 2 hours, heating to 150 ℃, and continuing to stir in vacuum for 3 hours to obtain a semi-finished product masterbatch.

Step 2:

(1) firstly, cutting 100 parts of carbon fiber by using a composite material cutting machine, washing with deionized water for 3 times, then soaking in 0.1mol/L KH550 and other amino-containing coupling agent solutions for 45min, finally heating at 110 ℃ for 45min, and repeating for 3 times to obtain the amino-modified carbon fiber.

(2) Amino modified carbon fiber is added into nickel sulfur hexahydrate (NiCl)₂·6H₂O) soaking for 30min, and adding NaBH₄Soaking in the solution for 30min, and washing with deionized water for 3 times.

(3) And (3) putting the treated carbon fiber into a chemical nickel plating solution, reacting for 90min, repeatedly washing for 3 times by using deionized water, and then putting into a 50 ℃ oven to bake for 90min to obtain the nickel-coated carbon fiber.

And step 3: taking 100 parts of the semi-finished product master batch, 8 parts of hydrogen-containing silicone oil with average hydrogen content of 1.1%, 0.3 part of 4000ppm platinum catalyst, 0.04 part of 3, 5-dimethyl-1-hexyne-3-alcohol, 30 parts of nickel-coated carbon fiber, 170 parts of 100 mu m nickel-coated graphite powder and 30 parts of dimethyl carbonate, and placing the mixture in a dispersion machine (the rotating speed is 100r) to stir for 10min to prepare the high-temperature addition type organic silicon electromagnetic shielding adhesive.

Comparative example one:

step 1: 100 parts of vinyl silicone oil having a viscosity of 1 ten thousand, 1.5 parts of silazane, and 0.5 part of distilled water were added to a kneader and stirred for 30 minutes. And adding 30 parts of white carbon black into the kneader in batches, stirring for 2 hours, heating to 150 ℃, and continuing to stir in vacuum for 3 hours to obtain a semi-finished product masterbatch.

Step 2: 100 parts of the master batch, 8 parts of hydrogen-containing silicone oil with the average hydrogen content of 1.1 percent, 0.4 part of 3000ppm platinum catalyst, 0.04 part of 3-methyl-1-butyne-3-ol, 200 parts of 150 mu m nickel powder and 20 parts of acetone are put into a dispersion machine (the rotating speed is 100r) and stirred for 10min, and the organic silicon electromagnetic shielding adhesive for comparison is prepared.

Comparative example two:

step 1: 100 parts of vinyl silicone oil having a viscosity of 1 ten thousand, 1.5 parts of silazane, and 0.5 part of distilled water were added to a kneader and stirred for 30 minutes. And adding 30 parts of white carbon black into the kneader in batches, stirring for 2 hours, heating to 150 ℃, and continuing to stir in vacuum for 3 hours to obtain a semi-finished product masterbatch.

Step 2: 100 parts of the master batch, 8 parts of hydrogen-containing silicone oil with the average hydrogen content of 1.1%, 0.4 part of platinum catalyst with the average hydrogen content of 3000ppm, 0.04 part of 3-methyl-1-butyn-3-ol, 200 parts of 150 mu m nickel-coated graphite powder and 20 parts of octamethyltrisiloxane are put into a dispersion machine (the rotating speed is 100r) and stirred for 10min, and the organosilicon electromagnetic shielding adhesive for comparison is prepared.

The following table shows the data of the examples and comparative examples

As can be seen from the table, compared with the prior art, the invention has the advantage that the performance of each index is greatly improved.

The invention has the beneficial effects that: according to the invention, the nickel-coated carbon fiber is added into the system, so that the system can be reinforced, and good conductivity and electromagnetic shielding property are provided. After the spot gluing and curing, the volume resistance is less than 40m omega cm, the shielding effectiveness reaches more than 120dB, the tensile strength reaches 4.0MPa, the tearing strength is more than 20N/mm, the volume resistivity is only increased by about 12.5 percent of the initial volume resistivity after the spot gluing and curing, and the electromagnetic shielding effect can be kept to about 90 percent of the initial volume resistivity after the spot gluing and curing.