Creep-resistant 3D printing electric conduction and heat conduction silicone rubber and preparation method thereof

Abstract

The invention discloses creep-resistant 3D printing electric conduction and heat conduction silicone rubber and a preparation method thereof. The creep-resistant 3D printing electric conduction and heat conduction silicone rubber comprises the following raw material components in parts by weight: 45-65 parts of polysiloxane; 3-5 parts of a creep resistant agent; 20-35 parts of a filler; 1-2 parts of a silane coupling agent; 2-5 parts of a cross-linking agent; 1-2 parts of an initiator; and 2-4 parts of a catalyst. The polysiloxane, the creep-resistant agent, the filler and other components are mixed according to a specific proportion, so that the prepared silicone rubber is light in weight, and the defect that metal powder is traditionally used as an electric conduction and heat conduction material and is heavy in weight is overcome; the composite material can be cured within 60 seconds after printing, is good in elasticity, creep resistance and electric conductivity and thermal conductivity, and can be rapidly manufactured and formed.

Description

Technical Field

[0001] The invention belongs to the technical field of silicone rubber and relates to a conductive and thermally conductive silicone rubber, and in particular to a creep-resistant 3D printing conductive and thermally conductive silicone rubber and a preparation method thereof. Background Art

[0002] 3D printing technology has brought extensive changes to modern design and production. 3D printing technology consists of three parts: 3D printing materials and molding process, high-precision three-dimensional design, and powerful molding equipment. It can be seen that the importance of 3D printing materials to the development of 3D printing is self-evident.

[0003] The Chinese invention patent with application number 202310397878.2 discloses a thermally conductive silicone rubber and its preparation method and application, which specifically relates to the field of functional polymer materials; the application uses two types of vinyl siloxanes, tetramethyl divinyl disiloxane and tetramethyl tetravinyl cyclotetrasiloxane, as monomers in the photocuring system, and mercapto silicone oil as a prepolymer, wherein the vinyl siloxane can reduce the viscosity of the silicone rubber, facilitate the filling of two types of thermally conductive fillers, flaky boron nitride and spherical alumina, and form a thermally conductive path in the silicone rubber. At the same time, the reasonably added thermally conductive fillers will not affect the rapid light-induced cross-linking reaction between the vinyl siloxane and the mercapto silicone oil. However, the thermally conductive silicone rubber needs to use two types of vinyl siloxanes, tetramethyl divinyl disiloxane and tetramethyl tetravinyl cyclotetrasiloxane, to reduce the viscosity of the silicone rubber, otherwise 3D printing cannot be performed. Summary of the invention

[0004] In order to solve the above technical problems, the object of the present invention is to provide a 3D printed conductive and thermally conductive silicone rubber with creep resistance, which quickly solidifies after printing and has the properties of good elasticity, good creep resistance, and good electrical and thermal conductivity.

[0005] In order to achieve the above object, the present invention provides a 3D printing conductive and thermally conductive silicone rubber with creep resistance, which comprises the following raw material components in parts by weight:

[0006] 45-65 parts of polysiloxane;

[0007] 3-5 parts of anti-creep agent;

[0008] 20-35 parts of filler;

[0009] 1-2 parts of silane coupling agent;

[0010] 2 to 5 parts of cross-linking agent;

[0011] 1-2 parts of initiator;

[0012] 2 to 4 parts of catalyst.

[0013] Optimally, the polysiloxane is a mixture of one or more selected from hydroxyl-terminated polydimethylsiloxane and siloxane-modified polyurethane.

[0014] Optimally, the anti-creep agent is a mixture of one or more selected from nano-silicon dioxide, nano-calcium carbonate and hydrophobic white carbon black.

[0015] Optimally, the filler is a mixture of one or more of aluminum nitride, carbon nanotubes, graphene oxide, carbon fiber and carbon black powder.

[0016] Optimally, the silane coupling agent is a mixture of one or more selected from KH550, KH560, KH570, KH580, DB171, DB151 and titanate complex.

[0017] Optimally, the crosslinking agent is a mixture of one or more selected from methyltrimethoxysilane, methyltriacetoxysilane, modified methyltriacetoxysilane, methyltributylidene oxime silane and di-tert-butyldiacetoxysilane.

[0018] Optimally, the initiator is one or two selected from 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2-hydroxy-2-methyl-1-phenylpropiophenone.

[0019] Optimally, the catalyst is a mixture of one or more selected from an organic guanidine catalyst, an organic tin catalyst, an acetylacetonate platinum catalyst, and a (trimethyl)methylcyclopentadiene platinum catalyst.

[0020] Another object of the present invention is to provide a method for preparing the above-mentioned 3D printed conductive and thermally conductive silicone rubber with creep resistance, comprising the following steps:

[0021] The formulated amount of polysiloxane, anti-creep agent and filler are mixed through a three-roll mill and added to a planetary mill. Then, a cross-linking agent, an initiator, a coupling agent and a catalyst are added and mixed evenly, and vacuum stirring is performed to defoam.

[0022] The creep-resistant 3D printed conductive and thermally conductive silicone rubber of the present invention is made to be light in weight by mixing various components such as polysiloxane, creep-resistant agent, filler, etc. in a specific proportion, thereby getting rid of the defects of heavy weight of the traditional conductive and thermally conductive material made of metal powder; the creep-resistant 3D printed conductive and thermally conductive silicone rubber realizes thermal conductivity: 1-2W / mk, viscosity: 30,000-50,000 mPa·S, hardness: 50-60HA, tensile strength: 5-8MPa, elongation: 80-120%, and tear strength: ≥15MPa. It can be cured within 60 seconds after printing, has good elasticity, good creep resistance, good electrical and thermal conductivity, and can realize rapid manufacturing and molding of composite materials. DETAILED DESCRIPTION

[0023] The 3D printed conductive and thermally conductive silicone rubber with anti-creep performance of the present invention comprises the following raw material components in parts by weight: 45-65 parts of polysiloxane; 3-5 parts of anti-creep agent; 20-35 parts of filler; 1-2 parts of silane coupling agent; 2-5 parts of cross-linking agent; 1-2 parts of initiator; and 2-4 parts of catalyst. By mixing the components such as polysiloxane, anti-creep agent, and filler in a specific proportion, the prepared silicone rubber is light in weight, getting rid of the defects of the traditional conductive and thermally conductive material with metal powder and heavy weight; it can be cured within 60 seconds after printing, has good elasticity, good creep resistance, good electrical and thermal conductivity, and can realize rapid manufacturing and molding of composite materials.

[0024] The polysiloxane is a mixture of one or more selected from hydroxyl-terminated polydimethylsiloxane and siloxane-modified polyurethane. The anti-creep agent is a mixture of one or more selected from nano-silicon dioxide, nano-calcium carbonate and hydrophobic white carbon black. The filler is a mixture of one or more selected from aluminum nitride, carbon nanotubes, graphene oxide, carbon fiber and carbon black powder. The silane coupling agent is a mixture of one or more selected from KH550, KH560, KH570, KH580, DB171, DB151 and titanate complex. The crosslinking agent is a mixture of one or more selected from methyltrimethoxysilane, methyltriacetoxysilane, modified methyltriacetoxysilane, methyltributanoximosilane and di-tert-butyldiacetoxysilane. The initiator is one or two selected from 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2-hydroxy-2-methyl-1-phenylpropiophenone. The catalyst is a mixture of one or more selected from an organic guanidine catalyst, an organic tin catalyst, an acetylacetonate platinum catalyst, and a (trimethyl)methylcyclopentadiene platinum catalyst.

[0025] The preparation method of the above-mentioned creep-resistant 3D printing conductive and thermally conductive silicone rubber comprises the following steps: mixing the formulated amount of polysiloxane, anti-creep agent and filler through a three-roll mill and adding them to a planetary mill, then adding a cross-linking agent, an initiator, a coupling agent and a catalyst and mixing them evenly, and vacuum stirring and defoaming.

[0026] In order to enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only embodiments of a part of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained under the premise of equivalent changes and modifications made by ordinary technicians in the field should belong to the scope of protection of the present invention.

[0027] Example 1

[0028] This embodiment provides a 3D printed conductive and thermally conductive silicone rubber with creep resistance and a preparation method thereof, as follows:

[0029] Add 50g of polysiloxane (hydroxy-terminated polydimethylsiloxane, Merck 481939), 4g of anti-creep agent (nano-silica, Jikang, average particle size 10nm), 22.5g of thermal conductive filler (aluminum nitride, 500 mesh, Nangong Xindun), 2.5g of graphene oxide (Merck 796034) and 2g of carbon fiber (chopped carbon fiber, specification 1mm, Yancheng Xiangsheng) into the planetary machine and stir evenly. Then grind with three rollers to fully knead the materials, add 1.5g of silane coupling agent (KH560), 4g of cross-linking agent (methyltrimethoxysilane), 1.5g of initiator (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone) and 2g of catalyst (tetramethylguanidine) and stir and mix evenly to obtain 3D printed conductive and thermally conductive silicone rubber with anti-creep performance.

[0030] Example 2

[0031] This embodiment provides a 3D printed conductive and thermally conductive silicone rubber with creep resistance and a preparation method thereof, which is basically the same as that in Embodiment 1, except that the amount used is different, as follows:

[0032] Add 45g of polysiloxane (hydroxy-terminated polydimethylsiloxane), 5g of anti-creep agent (nanosilica), 30g of thermal conductive filler (aluminum nitride), 4g of graphene oxide, and 1g of carbon fiber into the planetary machine and stir evenly. Then grind with three rollers to fully knead the materials, add 2g of silane coupling agent (KH560), 2g of cross-linking agent (methyltrimethoxysilane), 2g of initiator (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone), and 2g of catalyst (organic guanidine catalyst) and stir and mix evenly to obtain 3D printed conductive and thermally conductive silicone rubber with anti-creep performance.

[0033] Example 3

[0034] This embodiment provides a 3D printed conductive and thermally conductive silicone rubber with creep resistance and a preparation method thereof, which is basically the same as that in Embodiment 1, except that the amount used is different, as follows:

[0035] Add 65g of polysiloxane (hydroxy-terminated polydimethylsiloxane), 3g of anti-creep agent (nano-silica), 15g of thermal conductive filler (aluminum nitride), 3g of graphene oxide, and 2g of carbon fiber into the planetary machine and stir evenly. Then grind with three rollers to fully knead the materials, add 1g of silane coupling agent (KH560), 5g of cross-linking agent (methyltrimethoxysilane), 1g of initiator (2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone), and 4g of catalyst (organic guanidine catalyst) and stir and mix evenly to obtain 3D printed conductive and thermally conductive silicone rubber with anti-creep performance.

[0036] Comparative Example 1

[0037] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that the anti-creep agent is reduced to 1g.

[0038] Comparative Example 2

[0039] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that the anti-creep agent is used in excess to 10 g.

[0040] Comparative Example 3

[0041] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that the silane coupling agent (KH560) is used in excess of 5 g.

[0042] Comparative Example 4

[0043] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that the polysiloxane is amino-terminated polydimethylsiloxane (PEG-7 Changzhou Runqian Biological, 133779-14-3).

[0044] Comparative Example 5

[0045] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that the hydroxyl-terminated polydimethylsiloxane is used in excess to 80 g.

[0046] Comparative Example 6

[0047] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that the hydroxyl-terminated polydimethylsiloxane is used in excess to 30 g.

[0048] Comparative Example 7

[0049] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that the catalyst is a titanate catalyst (TC-TE).

[0050] Comparative Example 8

[0051] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that it does not contain graphene oxide.

[0052] Comparative Example 9

[0053] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that it does not contain carbon fiber.

[0054] Comparative Example 10

[0055] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that it does not contain an initiator.

[0056] Comparative Example 11

[0057] This example provides a silicone rubber and a preparation method thereof, which is basically the same as that in Example 1, except that it does not contain a catalyst.

[0058] The performance of the silicone rubber in Examples 1-3 and Comparative Examples 1-11 was tested, and the results are shown in Table 1.

[0059] Table 1 Performance test table of silicone rubber in Examples 1-3 and Comparative Examples 1-11

[0060]

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. At the same time, the above description should be understandable and implementable for those with ordinary knowledge in the relevant technical field. Therefore, other equivalent changes or modifications that do not deviate from the concept disclosed by the present invention should be included in the scope of protection of the present invention.

Claims

1. A 3D printed conductive and thermally conductive silicone rubber with creep resistance, characterized in that: It includes the following raw material components in parts by weight: 45-65 parts of polysiloxane; 3-5 parts of anti-creep agent; 20~35 parts of filler; Silane coupling agent 1~2 parts; 2~5 parts of cross-linking agent; 1~2 parts of initiator; 2~4 parts of catalyst.

2. The 3D printing conductive and thermally conductive silicone rubber with creep resistance according to claim 1, characterized in that: The polysiloxane is a mixture of one or more selected from hydroxyl-terminated polydimethylsiloxane and siloxane-modified polyurethane.

3. The creep-resistant 3D printing conductive and thermally conductive silicone rubber according to claim 1, characterized in that: The anti-creep agent is a mixture of one or more selected from nano silicon dioxide, nano calcium carbonate and hydrophobic white carbon black.

4. The creep-resistant 3D printing conductive and thermally conductive silicone rubber according to claim 1, characterized in that: The filler is a mixture of one or more of aluminum nitride, carbon nanotubes, graphene oxide, carbon fiber and carbon black powder.

5. The creep-resistant 3D printing conductive and thermally conductive silicone rubber according to claim 1, characterized in that: The silane coupling agent is a mixture of one or more selected from KH550, KH560, KH570, KH580, DB171, DB151 and titanate complex.

6. The creep-resistant 3D printing conductive and thermally conductive silicone rubber according to claim 1, characterized in that: The crosslinking agent is a mixture of one or more selected from methyltrimethoxysilane, methyltriacetoxysilane, modified methyltriacetoxysilane, methyltributylidene oxime silane and di-tert-butyldiacetoxysilane.

7. The creep-resistant 3D printing conductive and thermally conductive silicone rubber according to claim 1, characterized in that: The initiator is one or two selected from 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2-hydroxy-2-methyl-1-phenylpropiophenone.

8. The creep-resistant 3D printing conductive and thermally conductive silicone rubber according to claim 1, characterized in that: The catalyst is a mixture of one or more selected from an organic guanidine catalyst, an organic tin catalyst, an acetylacetonate platinum catalyst, and a (trimethyl)methylcyclopentadiene platinum catalyst.

9. The method for preparing the 3D printed conductive and thermally conductive silicone rubber with creep resistance according to any one of claims 1 to 8, characterized in that: The following steps are involved: The formulated amount of polysiloxane, anti-creep agent and filler are mixed through a three-roll mill and added to a planetary mill. Then, a cross-linking agent, an initiator, a coupling agent and a catalyst are added and mixed evenly, and vacuum stirring is performed to defoam.

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