Intrinsic heat-conducting high-molecular polymer, preparation method thereof and heat-conducting polymer composite material

Abstract

The invention belongs to the technical field of heat-conducting macromolecules, and particularly discloses an intrinsic heat-conducting high-molecular polymer, a preparation method thereof and a heat-conducting polymer composite material. The intrinsic heat-conducting high-molecular polymer is obtained by carrying out ring-opening metathesis polymerization reaction on one or two of monomers with structures as shown in formulas I-III. The intrinsic heat-conducting high-molecular polymer provided by the invention can form an ordered array with high pi-pi stacking interaction through self-assembly, so that an intrinsic planar heat conductivity is generated, and the intrinsic heat-conducting high-molecular polymer has good heat-conducting property. Compared with a traditional heat-conducting material, the heat-conducting material containing the intrinsic heat-conducting high-molecular polymer has the characteristics of being lighter, more flexible and more environment-friendly. The intrinsic high-molecular polymer and the filler are compounded to obtain the heat-conducting polymer composite material, so that the heat-conducting property of the heat-conducting material can be further improved, and the application requirement of the high-heat-conducting high-molecular material is met.

Description

Technical Field

[0001] The present invention relates to the field of thermal conductive polymer technology, and in particular to an intrinsic thermal conductive polymer and a preparation method thereof and a thermal conductive polymer composite material. Background Art

[0002] Thermally conductive polymers are a type of polymer material with excellent thermal conductivity. They have the advantages of good thermal conductivity, light weight, corrosion resistance, and good insulation performance. They are widely used in heat dissipation modules of electronic equipment, LED lighting, automotive electronics, aerospace and other fields, providing new solutions for thermal management. Thermally conductive polymers are usually composed of thermally conductive fillers and polymer matrices. Commonly used thermally conductive fillers include aluminum oxide, silicon oxide, carbon nanotubes, etc. These fillers have good thermal conductivity. The polymer matrix provides the mechanical properties and processing properties of the material, and can form good interface compatibility with the filler, which helps to improve the overall thermal conductivity.

[0003] With the continuous development of science and technology, the research and application prospects of thermal conductive polymers will be broader. However, at present, the thermal conductivity of the polymer matrix material in thermal conductive materials is very low, and the thermal conductivity mainly depends on the type and amount of filler. In addition, due to the certain restrictions on the amount of added filler, it is difficult to further improve the thermal conductivity of thermal conductive materials, which has limitations in meeting the thermal conductivity requirements of miniaturized and lightweight equipment.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide an intrinsically thermally conductive polymer and a preparation method thereof and a thermally conductive polymer composite material, aiming to solve the problem that the thermal conductivity of the polymer matrix material in the existing thermally conductive materials is very low and difficult to improve.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect of the present invention, there is provided an intrinsically thermally conductive polymer obtained by ring-opening metathesis polymerization of one or two monomers having structures shown in Formulas I to III:

[0008]

[0009] Among them, R1 is is an integer between 1 and 20, and R2 is

[0010] The intrinsically thermally conductive high molecular polymer provided by the present invention forms an ordered array with a high degree of π-π stacking interaction through self-assembly, thereby generating an intrinsic planar thermal conductivity and having good thermal conductivity, thereby overcoming the problem of very low thermal conductivity of high molecular polymer matrix materials in traditional thermally conductive materials.

[0011] Optionally, the intrinsic thermal conductive polymer has a repeating unit of one of the structures shown in formulas a to d:

[0012]

[0013]

[0014] Among them, R1 is n is an integer from 1 to 20; R2 is

[0015] The second aspect of the present invention provides a method for preparing the intrinsic thermal conductive polymer, comprising the steps of:

[0016] preparing the monomer;

[0017] Dissolving one or two of the monomers in a first organic solvent, introducing an inert gas and stirring to obtain a monomer solution;

[0018] Dissolving [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazole-2-ylidene][bis(3-bromopyridine)]benzylidene ruthenium dichloride (Ru-III) in a second organic solvent to obtain a catalyst solution;

[0019] The catalyst solution is injected into the monomer solution, and the mixture is stirred for reaction to obtain the intrinsic thermal conductive high molecular polymer.

[0020] In the preparation method, a monomer or two different monomers undergo a ring-opening metathesis polymerization (ROMP) reaction under the action of a catalyst Ru-III to generate the intrinsic thermal conductive polymer. The synthesis route is as follows:

[0021]

[0022]

[0023] Optionally, the first organic solvent is dichloromethane or dimethylformamide.

[0024] Optionally, the second organic solvent is dichloromethane or dimethylformamide.

[0025] Optionally, the inert gas may be nitrogen or argon.

[0026] Optionally, the concentration of the monomer in the monomer solution is 0.01 to 1 g / mL.

[0027] Optionally, the concentration of [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazole-2-ylidene][bis(3-bromopyridine)]benzylideneruthenium dichloride in the catalyst solution is 1 to 50 mg / mL.

[0028] Wherein, optionally, preparing the monomer comprises the steps of:

[0029] Dissolving norbornene-5,6-dicarboxylic anhydride in toluene to obtain solution A, dissolving an amine compound in toluene to obtain solution B, and adding solution B to solution A to obtain a mixed solution C;

[0030] Adding 4-dimethylaminopyridine to the mixed solution C, heating and stirring to react, settling, and purifying to obtain the monomer represented by the formula I or the formula II;

[0031] Alternatively, further, the monomer represented by formula II prepared above is dissolved in tetrahydrofuran, and the borane solution is added to the solid solution under an inert atmosphere and low temperature conditions, and then refluxed to react, and filtered and purified to obtain the monomer represented by formula III;

[0032] Wherein, the amino compound is R1 is n is an integer from 1 to 20, R2 is

[0033]

[0034] A third aspect of the present invention provides a thermally conductive polymer composite material, comprising the intrinsic thermally conductive high molecular polymer and a filling material.

[0035] Optionally, the filler material is one or more of graphene, carbon nanotubes, hexagonal boron nitride, aluminum nitride, silicon carbide, aluminum hydroxide, magnesium hydroxide, aluminum oxide and zinc oxide. Adding a certain amount of thermally conductive filler to the intrinsically thermally conductive polymer can further increase the thermal conductivity.

[0036] Optionally, the mass ratio of the filling material to the intrinsic thermal conductive high molecular polymer is (0.01-1):1.

[0037] Beneficial effects:

[0038] The present invention provides an intrinsic thermally conductive polymer and a preparation method thereof and a thermally conductive polymer composite material. The intrinsic thermally conductive polymer can form an ordered array with a high degree of π-π stacking interaction through self-assembly, thereby generating an intrinsic planar thermal conductivity and having good thermal conductivity. Compared with traditional thermally conductive materials, the intrinsic thermally conductive polymer of the present invention is used as a matrix material, and due to its good thermal conductivity, the thermally conductive material has the characteristics of being lighter, more flexible and more environmentally friendly. At the same time, the intrinsic polymer and filler can be composited to further improve the thermal conductivity of the thermally conductive material, thereby meeting the application requirements of high thermally conductive polymer materials. DETAILED DESCRIPTION

[0039] The present invention provides an intrinsically thermally conductive polymer and a preparation method thereof and a thermally conductive polymer composite material. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0041] The following describes it in detail through specific embodiments.

[0042] Example 1

[0043] The synthetic route of monomer 1 is as follows:

[0044]

[0045] The specific synthesis steps are as follows: 3.92 g of norbornene-5,6-dicarboxylic anhydride is dissolved in 50 ml of toluene solution and stirred to obtain solution A. 2 g of 2,2,2-trifluoroethylamine is dissolved in 10 ml of toluene to obtain solution B, solution B is added dropwise to solution A, 0.488 g of 4-dimethylaminopyridine (DMAP) is added after mixing to obtain a uniform mixture, and the mixture is stirred at 80° C. for 12 h. After cooling, the reaction mixture is dropped into excess water and filtered to obtain a solid, and the solid is purified by silica gel column chromatography to obtain monomer 1.

[0046] Example 2

[0047] The route for synthesizing the intrinsic thermal conductive polymer from monomer 1 is as follows:

[0048]

[0049] The specific synthesis steps are as follows: 1.33 mg of monomer 1 is dissolved in 10 ml of dichloromethane, nitrogen is introduced, and the mixture is stirred at 30°C to obtain a monomer 1 solution. 9 mg of catalyst [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazole-2-ylidene][bis(3-bromopyridine)]benzylidene ruthenium dichloride (Ru-III) is dissolved in 1 ml of dichloromethane, and then injected into the monomer 1 solution through a syringe, and the mixture is stirred at 30°C for 2 hours to obtain an intrinsic thermal conductive polymer 1.

[0050] Example 3

[0051] The synthetic route of monomer 2 is as follows:

[0052]

[0053] The specific synthesis steps are as follows: 4.38g of 4-aminophenylboronic acid pinacol ester, 1.92g of dibromothiophene and 6.63g of potassium carbonate are dissolved in 60ml of 1,4-dioxane and 20ml of water, and then 0.46g of tetrakis(triphenylphosphine)palladium is added, and the mixture is heated to 110°C and stirred for 12h. After the reaction is completed, the reaction mixture is extracted with dichloromethane, washed with brine, dried and concentrated, and purified on a silica gel column using petroleum ether / dichloromethane as a solvent to obtain a light yellow powder of the reactant 1, which is 4,4'-(thiophene-2,5-diyl)diphenylamine.

[0054] 1.96 g of norbornene-5,6-dicarboxylic anhydride was dissolved in 50 ml of toluene, and 2.66 g of 4,4'-(thiophene-2,5-diyl)diphenylamine was dissolved in 10 ml of toluene, and the mixture was dripped into the toluene solution of norbornene-5,6-dicarboxylic anhydride. 0.244 g of DMAP was added at room temperature, and the mixture was stirred at 110°C for 12 hours. After cooling, the reaction mixture was dripped into water and filtered to obtain a solid powder of monomer 2.

[0055] Example 4

[0056] The route for synthesizing the characteristic heat-conducting polymer from monomer 2 is as follows:

[0057]

[0058] The specific synthesis steps are as follows: 1.12 mg of the monomer 2 prepared in Example 3 is dissolved in 10 ml of dimethylformamide (DMF), nitrogen is introduced, and the mixture is stirred at 30° C. to obtain a monomer 2 solution. 18 mg of the catalyst Ru-III is dissolved in 1 ml of DMF, and then injected into the monomer solution through a syringe, and the mixture is stirred at 30° C. for 2 h to obtain an intrinsic thermal conductive polymer 2.

[0059] Example 5

[0060] The synthetic route of monomer 3 is as follows:

[0061]

[0062] The specific synthesis steps are as follows: 2.1 g of reactant 2 is added to 30 ml of dry tetrahydrofuran (THF) to obtain a solution of reactant 2, which is cooled to 0°C under argon, 0.35 g of borane is dissolved in 25 ml of THF, and slowly added dropwise to the solution of reactant 2. The mixture is then refluxed for reaction for 12 hours. After the reaction is completed and reaches room temperature, the mixture is poured into 500 ml of ice water and filtered, and the solid is purified on a silica gel column using EtOH and PE as solvents to obtain monomer 3 as a white powder.

[0063] Example 6

[0064] The route for synthesizing the characteristic thermal conductive polymer from monomer 3 is as follows:

[0065]

[0066] The specific synthesis steps are as follows: 1 g of the monomer 3 prepared in Example 5 is dissolved in 10 ml of DMF, nitrogen is introduced, and the mixture is stirred at 30° C. to obtain a monomer 3 solution. 22 mg of the catalyst Ru-III is dissolved in 1 ml of DMF, and then injected into the monomer solution through a syringe, and stirred at 30° C. for 2 h to obtain an intrinsic thermal conductive polymer 3.

[0067] Example 7

[0068] The synthetic route of monomer 4 is as follows (by modifying monomer 3):

[0069]

[0070] The specific synthesis steps are as follows: 3.92g of monomer 3 is dissolved in 40ml of dichloromethane solution, and then 5.22g of m-chloroperbenzoic acid (m-CPBA) in 40ml of dichloromethane solution is added dropwise, and the mixture is dripped in about 10 minutes. The obtained red to brown reaction mixture is stirred at room temperature for 72 hours, and after the reaction is completed, the solid is filtered out, and the filtrate is washed with saturated NaHCO3 solution, dried with MgSO4 and concentrated in vacuo, and purified on a silica gel column using dichloromethane as solvent to obtain a yellow solid, which is monomer 4.

[0071] Example 8

[0072] The route for synthesizing the characteristic heat-conducting polymer from monomer 4 is as follows:

[0073]

[0074] The specific synthesis steps are as follows: 1.07 g of the monomer 4 prepared in Example 7 is dissolved in 20 ml of DMF, nitrogen is introduced, and the mixture is stirred at 30° C. to obtain a monomer 4 solution. 20 mg of the catalyst Ru-III is dissolved in 1 ml of DMF, and then injected into the monomer 4 solution through a syringe, and the mixture is stirred at 30° C. for 2 h to obtain an intrinsic thermal conductive polymer 4.

[0075] Example 9

[0076] The route for synthesizing the intrinsic heat-conducting polymer from monomer 1 and monomer 4 is as follows:

[0077]

[0078] The specific synthesis steps are as follows: 1.8 g of monomer 4 prepared in Example 7 and 1.96 g of monomer 1 prepared in Example 1 are dissolved in 100 ml of DMF, nitrogen is introduced, and the mixture is stirred evenly to obtain a monomer solution. 30 mg of catalyst Ru-III is dissolved in 1 ml of CH2Cl2 to obtain a catalyst solution, and the catalyst solution is injected into the monomer solution with a syringe, and the mixture is stirred vigorously at 30°C. After reacting for 2 hours, the corresponding intrinsic thermal conductive polymer 5 is obtained.

[0079] Example 10

[0080] 1 g of the intrinsic thermal conductive high molecular polymer prepared in Example 9 was taken, 0.2 g of hexagonal boron nitride powder was added, and the mixture was stirred for 5 hours to obtain a thermal conductive polymer composite material 6.

[0081] The intrinsic thermally conductive polymers 1 to 5 prepared in the above Examples 1 to 9 and the thermally conductive polymer composite material 6 prepared in Example 10 were tested, and their thermal conductivities are shown in Table 1 below.

[0082] Table 1

[0083]

[0084] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. An intrinsically thermally conductive polymer, characterized in that: The following is obtained by ring-opening metathesis polymerization of one or two monomers having structures shown in formulas I to III: Among them, R1 is n is an integer from 1 to 20, R2 is 2. The intrinsically thermally conductive polymer according to claim 1, characterized in that: A repeating unit having one of the structures shown in formulas a to d: Among them, R1 is n is an integer from 1 to 20; R2 is 3. A method for preparing an intrinsically thermally conductive polymer as claimed in claim 1, characterized in that: Includes steps: preparing the monomer; Dissolving one or two of the monomers in a first organic solvent, introducing an inert gas and stirring to obtain a monomer solution; Dissolving [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazole-2-ylidene][bis(3-bromopyridine)]benzylideneruthenium dichloride in a second organic solvent to obtain a catalyst solution; The catalyst solution is injected into the monomer solution, and the mixture is stirred for reaction to obtain the intrinsic thermal conductive high molecular polymer.

4. The method for preparing an intrinsically thermally conductive polymer according to claim 3, characterized in that: The method for preparing the monomer comprises the steps of: Dissolving norbornene-5,6-dicarboxylic anhydride in toluene to obtain solution A, dissolving an amine compound in toluene to obtain solution B, and adding solution B to solution A to obtain a mixed solution C; Adding 4-dimethylaminopyridine to the mixed solution C, heating and stirring to react, settling, and purifying to obtain the monomer represented by the formula I or the formula II; or, The monomer of formula II prepared above is dissolved in tetrahydrofuran, and the borane solution is added to the solid solution under an inert atmosphere and low temperature conditions, and then refluxed to react, and then filtered and purified to obtain the monomer of formula III; Wherein, the amino compound is R1 is Wherein, n is an integer from 1 to 20, and R2 is 5. The method for preparing an intrinsically thermally conductive polymer according to claim 3, characterized in that: The first organic solvent is dichloromethane or dimethylformamide; and / or the second organic solvent is dichloromethane or dimethylformamide.

6. The method for preparing an intrinsically thermally conductive polymer according to claim 3, characterized in that: The concentration of the monomer in the monomer solution is 0.01-1 g / mL.

7. The method for preparing an intrinsically thermally conductive polymer according to claim 3, characterized in that: The concentration of [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazole-2-ylidene][bis(3-bromopyridine)]benzylidene ruthenium dichloride in the catalyst solution is 1 to 50 mg / mL.

8. A thermally conductive polymer composite material, characterized in that: It comprises the intrinsic thermal conductive high molecular polymer as claimed in claim 1 and a filling material.

9. The thermally conductive polymer composite material according to claim 8, characterized in that: The filling material is one or more of graphene, carbon nanotubes, hexagonal boron nitride, aluminum nitride, silicon carbide, aluminum hydroxide, magnesium hydroxide, aluminum oxide and zinc oxide.

10. The thermally conductive polymer composite material according to claim 8, characterized in that: The mass ratio of the filling material to the intrinsic thermal conductive high molecular polymer is (0.01-1):1.

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