Heat-conducting polypropylene composite material suitable for high-power LED (light-emitting diode) lamp radiating device as well as preparation and application thereof

Abstract

The invention discloses a heat-conducting polypropylene composite material suitable for a high-power LED (light-emitting diode) lamp radiating device as well as a preparation method and application of the heat-conducting polypropylene composite material. The composite material comprises the following raw materials in parts by mass: 35-40 parts of polypropylene, 35-40 parts of a heat conducting agent, 13-17 parts of a reinforcing agent, 1-5 parts of a toughening agent, 1-5 parts of a compatilizer and 0.1-0.3 part of a dispersing agent, the heat conduction agent comprises graphene, spherical graphite, hexagonal flaky magnesium hydroxide and calcium carbonate; in the heat conduction agent, the mass ratio of the graphene is not less than 85%, the mass ratio of the spherical graphite is 4-7%, the mass ratio of the hexagonal flaky magnesium hydroxide is 4-7%, and the mass ratio of the calcium carbonate is 1-3%. The preparation method comprises the following steps: uniformly mixing the raw materials except the reinforcing agent, adding the mixture into a main feeding port of a double-screw extruder, adding the reinforcing agent into an exhaust port of the double-screw extruder, melting, extruding, cooling and drying.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heat-conducting polypropylene composites, in particular to a heat-conducting polypropylene composite suitable for a heat dissipation device of a high-power LED lamp and a preparation method and application thereof. BACKGROUND

[0002] At present, in order to improve the heat dissipation problem of the high-power LED lamp device, one of the better strategies is to use polypropylene plastic with high thermal conductivity after filling graphene material. In order to achieve good heat conduction effect, it is usually necessary to fill a large amount of graphene material in the polypropylene base material, but it will bring some adverse effects to the heat-conducting polypropylene material. First, high filling of graphene material often makes the cost of polypropylene composite material further increase; second, high filling of graphene also makes the flowability of polypropylene composite material poor, which is not only not conducive to the injection molding processing of the material, but also more easily causes the floating fiber phenomenon of the injection molded part of the glass fiber reinforced polypropylene material; in addition, high filling of graphene material makes the mechanical properties of polypropylene composite material low, so that the high-power LED lamp heat dissipation device is brittle; these adverse factors are very obvious in black graphene heat-conducting polypropylene, which is very unfavorable for the popularization and use of graphene high-thermal-conductivity polypropylene material.

[0003] After searching, the following prior art is found: The patent specification with publication number CN119060455A discloses a high-thermal-conductivity low-conductivity long-glass-fiber reinforced polypropylene composite material. The polypropylene composite material is prepared from the following components in parts by mass: polypropylene resin: 40-80 parts; polyester fiber: 4-8 parts; long glass fiber: 4-8 parts; graphene: 5-9 parts; boron nitride: 5-9 parts; silicon carbide: 2-3 parts; calcium carbonate: 4-6 parts; compatibilizer: 1-3 parts; antioxidant: 2-3 parts; coupling agent: 1-2 parts. The patent technology uses the combination of graphene, boron nitride, silicon carbide, and calcium carbonate to prepare a polypropylene composite material with stable thermal conductivity, mechanical properties, and electrical properties in harsh environments such as high temperature, high humidity, and chemical corrosion, and the material is environmentally friendly. However, the patent technology does not provide any performance test data, and the graphene content is low, which is not suitable for high-power LED lamp heat dissipation devices.

[0004] The patent specification with publication number CN108727670A discloses an insulating heat-conducting cable material, which comprises the following raw materials in parts by weight: high-density polyethylene 20-30 parts, graphene-modified polypropylene 10-20 parts, ethylene-vinyl acetate copolymer 15-25 parts, gum arabic 7-11 parts, montmorillonite 3-6 parts, light calcium carbonate 4-8 parts, glass fiber 3-7 parts, polyethylene wax 2-4 parts, calcium stearate 1-3 parts, flame retardant 6-9 parts, plasticizer 2-5 parts, and reinforcing agent 2-4 parts. The flame retardant is a mixture of magnesium hydroxide, aluminum hydroxide, antimony trioxide, and silicon carbide, and the mass ratio of magnesium hydroxide, aluminum hydroxide, antimony trioxide, and silicon carbide is 3:3:2:1. The patent technology claims that the insulating heat-conducting cable material has high thermal conductivity, but does not provide relevant performance test data. After analysis, the graphene content in the insulating heat-conducting cable material of the patent technology is very low, which is not suitable for high-power LED lamp heat dissipation devices. SUMMARY

[0005] The present application provides a kind of heat-conducting polypropylene composite material suitable for high-power LED lamp heat dissipation device and its preparation method and application, to solve the technical difficulty that current heat-conducting polypropylene is difficult to be promoted and used due to the cost of filling a large number of graphene materials, flowability decline and performance decline, develop low cost, easy processing and good mechanical properties of high heat-conducting polypropylene composite material.

[0006] Specific technical solutions are as follows: In the first aspect, the present application provides a kind of heat-conducting polypropylene composite material suitable for high-power LED lamp heat dissipation device, and the raw material composition includes, in mass fraction: polypropylene 35-40 parts (for example, 39 parts, etc.), heat-conducting agent 35-40 parts, reinforcing agent 13-17 parts (for example, 15 parts, etc.), toughening agent 1-5 parts (for example, 3 parts, etc.), compatible agent 1-5 parts (for example, 3 parts, etc.), dispersing agent 0.1-0.3 parts (for example, 0.2 parts, etc.); The heat-conducting agent includes graphene, spherical graphite, hexagonal flake magnesium hydroxide and calcium carbonate; in the heat-conducting agent, the mass fraction of graphene is not less than 85% (for example, 87.5%, etc.), the mass fraction of spherical graphite is 4%-7% (for example, 5%, 6.25%, etc.), the mass fraction of hexagonal flake magnesium hydroxide is 4%-7% (for example, 5%, 6.25%, etc.), and the mass fraction of calcium carbonate is 1%-3% (for example, 2.5%, etc.).

[0007] In order to make the heat-conducting polypropylene composite material better for high-power LED lamp heat dissipation device, in some preferred examples, the total mass fraction of polypropylene, heat-conducting agent, reinforcing agent, toughening agent and compatible agent of the heat-conducting polypropylene composite material suitable for high-power LED lamp heat dissipation device is 100 parts.

[0008] In order to make the heat-conducting polypropylene composite material better used in the heat dissipation device of the high-power LED lamp, in some preferred examples, the mass of the heat-conducting agent is equal to or greater than the mass of the polypropylene.

[0009] In order to make the heat-conducting polypropylene composite material better used in the heat dissipation device of the high-power LED lamp, in some preferred examples, the mass ratio of the spherical graphite, the hexagonal flaky magnesium hydroxide and the calcium carbonate in the heat-conducting agent is 2:2:1.

[0010] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the polypropylene is PP 1100N, and the melt index thereof is 10 g / 10 min under the condition of 230℃ and 2.16 kg.

[0011] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the graphene is graphene microsheet.

[0012] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the reinforcing agent is glass fiber. Further, the glass fiber is long glass fiber.

[0013] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the toughening agent is POE 8150.

[0014] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the compatibilizing agent is polypropylene grafted maleic anhydride.

[0015] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the dispersing agent is AC-6A wax.

[0016] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the raw material composition further comprises any one or more of the following in mass fraction: 0.1-0.3 parts of primary antioxidant, 0.1-0.3 parts of secondary antioxidant, and 0.1-0.3 parts of lubricant.

[0017] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the primary antioxidant is antioxidant 1010.

[0018] In some preferred examples, the heat-conducting polypropylene composite material suitable for the heat dissipation device of the high-power LED lamp, the secondary antioxidant is antioxidant 168.

[0019] In some preferred examples, the lubricant is ethylene bis-stearamide.

[0020] In the second aspect, the application provides a preparation method of the heat-conducting polypropylene composite material for the heat dissipation device of the high-power LED lamp, comprising: mixing and uniformly adding raw materials except the reinforcing agent into the main feeding port of the double-screw extruder, adding the reinforcing agent into the exhaust port of the double-screw extruder, and obtaining the heat-conducting polypropylene composite material for the heat dissipation device of the high-power LED lamp through melting, extrusion, cooling and drying.

[0021] In some preferred examples, the temperature of each partition of the barrel of the double-screw extruder is kept between 160-230 DEG C.

[0022] In some preferred examples, the rotating speed of the screw of the double-screw extruder is 300-400 rpm, for example, 350 rpm, etc.

[0023] In some preferred examples, the preparation method further comprises granulating after drying, and the heat-conducting polypropylene composite material for the heat dissipation device of the high-power LED lamp is in the form of granules.

[0024] In the third aspect, the application provides an application of the heat-conducting polypropylene composite material in the preparation of the heat dissipation device of the high-power LED lamp.

[0025] The application greatly improves the mechanical properties of the composite material by introducing the reinforcing agent such as glass fiber, and improves the thermal conductivity of the composite material by using the polypropylene grafted maleic anhydride and other compatibilizers.

[0026] The application reduces the cost of the composite material and improves the mechanical properties and fluidity of the composite material by the synergistic effect of the low-cost heat-conducting agents such as spherical graphite, hexagonal magnesium hydroxide and calcium carbonate, while ensuring the thermal conductivity of the composite material.

[0027] The use of the dispersant is beneficial to the dispersion of the heat-conducting agent and the glass fiber in the polypropylene, which helps to improve the thermal conductivity of the material and improve the appearance of the material.

[0028] Compared with the prior art, the application has the following beneficial effects: The application greatly improves the strength of the polypropylene composite material and has good toughness by properly matching the reinforcing agent such as glass fiber and the compatilizer such as polypropylene grafted maleic anhydride; in addition, the thermal conductivity of the polypropylene composite material is further improved under the addition of the compatilizer such as polypropylene grafted maleic anhydride and the dispersant; furthermore, the composite material has good flowability, mechanical property, thermal conductivity and low cost by the compounding of the low-cost thermal conductive agent. DETAILED DESCRIPTION

[0029] The application will be further described below in combination with specific examples. It should be understood that the examples are only used to illustrate the application and not used to limit the scope of the application.

[0030] The operation methods not specified in the following examples are generally carried out according to the conventional conditions or the conditions suggested by the manufacturers.

[0031] The raw materials involved in the following examples are described as follows: Polypropylene type PP 1100N, the melt index thereof is 10 g / 10 min under the condition of 230℃ and 2.16 kg.

[0032] Graphene microsheet DRM-P005, Knauf company.

[0033] Spherical graphite, Mettler Stone company.

[0034] Hexagonal flaky magnesium hydroxide, Ival company.

[0035] Calcium carbonate, Kolon company.

[0036] AC-6A wax, Honeywell.

[0037] Table 1 shows the raw material formula of the thermal conductive polypropylene composite material of each example, and the unit is mass part.

[0038] Table 1 The preparation method of the thermal conductive polypropylene composite material of each example comprises: mixing the raw materials except the long glass fiber uniformly in a high-speed mixer, then feeding into the main feeding port of a double-screw extruder, feeding the long glass fiber into the exhaust port of the double-screw extruder, melting and extruding through the double-screw extruder, the extrusion temperature is 160-230℃, the screw rotation speed is 350 rpm, then cooling, drying and pelletizing into granules to obtain the thermal conductive polypropylene composite material.

[0039] Table 2 shows the performance test data and the appearance of the injection molded parts of the thermal conductive polypropylene composite material obtained in each example.

[0040] Table 2 From the test results of Example 1 and Example 2, it can be seen that only the addition of a sufficient amount of glass fiber can improve the overall mechanical properties of the polypropylene composite material.

[0041] From the test results of Example 2 and Example 3, it can be seen that polypropylene grafted maleic anhydride helps the compatibility of the resin and the inorganic filler, and improves the mechanical properties and thermal conductivity of the composite material.

[0042] From the comparison of Example 3 and Example 4, it can be seen that the use of part of the spherical graphite to replace the graphene microsheet can improve the flowability of the material, but the mechanical properties and thermal conductivity of the composite material decrease.

[0043] From the comparison of Example 3 and Example 5, it can be seen that the use of part of the hexagonal flaky magnesium hydroxide to replace the graphene microsheet improves the flowability and mechanical properties of the composite material, but the thermal conductivity of the composite material decreases.

[0044] From the comparison of Example 3 to Example 6, it can be seen that the combination of spherical graphite, hexagonal flaky magnesium hydroxide and calcium carbonate makes the polypropylene composite material have good comprehensive performance. It is believed that the spherical graphene, hexagonal flaky magnesium hydroxide, calcium carbonate and graphene play a synergistic effect, and build a good thermal conduction network, so that the thermal conductivity of the composite material does not decrease significantly, and at the same time, the mechanical properties of the composite material are improved. In addition, the inventors have found that the key to achieving high thermal conductivity is still the graphene, and the proportion of graphene in the thermal conductor cannot be too low. Spherical graphite, hexagonal flaky magnesium hydroxide and calcium carbonate only play an auxiliary role and cannot replace graphene in large quantities, otherwise the obtained composite material will not be suitable for high-power LED lamp heat dissipation devices.

[0045] From the comparison of Example 6 and Example 7, it can be seen that an appropriate amount of dispersant is beneficial to the dispersion of glass fiber and the improvement of the flowability of the composite material, which is finally beneficial to the improvement of the appearance of the product.

[0046] In summary, from the comprehensive cost and comprehensive performance, Example 7 is a better solution.

[0047] In addition, it should be understood that after reading the above description of the present application, those skilled in the art can make various modifications or modifications to the present application, and these equivalent forms also fall within the scope defined by the claims attached to the present application.

Claims

1. A heat conductive polypropylene composite material suitable for use in a heat sink for a high-power LED luminaire, characterized in that, The raw material composition includes, in mass fraction: polypropylene 35-40 parts, thermal conductive agent 35-40 parts, reinforcing agent 13-17 parts, toughening agent 1-5 parts, compatibilizer 1-5 parts, and dispersing agent 0.1-0.3 parts; The thermal conductive agent includes graphene, spherical graphite, hexagonal flaky magnesium hydroxide, and calcium carbonate; in the thermal conductive agent, the mass fraction of graphene is not less than 85%, the mass fraction of spherical graphite is 4-7%, the mass fraction of hexagonal flaky magnesium hydroxide is 4-7%, and the mass fraction of calcium carbonate is 1-3%.

2. The thermally conductive polypropylene composite material suitable for high-power LED luminaire heat dissipation device according to claim 1, characterized in that, The total mass fraction of polypropylene, thermal conductive agent, reinforcing agent, toughening agent, and compatibilizer is 100 parts.

3. The thermally conductive polypropylene composite material suitable for high power LED luminaire heat sink device according to claim 1, characterized in that, The mass of the thermal conductive agent is equal to or greater than the mass of the polypropylene.

4. The thermally conductive polypropylene composite material suitable for high power LED luminaire heat sink device according to claim 1, characterized in that, In the thermal conductive agent, the mass ratio of spherical graphite, hexagonal flaky magnesium hydroxide, and calcium carbonate is 2:2:

1.

5. The thermally conductive polypropylene composite suitable for high power LED luminaire heat sink device according to claim 1, wherein, The polypropylene is PP 1100N, and the melt index thereof under the condition of 230℃ and 2.16kg is 10 g / 10 min; The graphene is graphene microsheet; The reinforcing agent is glass fiber; the glass fiber is long glass fiber; The toughening agent is POE 8150; The compatibilizer is polypropylene grafted maleic anhydride; The dispersing agent is AC-6A wax.

6. The heat-conducting polypropylene composite material suitable for heat dissipation device of high-power LED lamps and lanterns according to any one of claims 1-5, characterized in that, The raw material composition further includes, in mass fraction, any one or several of the following: primary antioxidant 0.1-0.3 parts, secondary antioxidant 0.1-0.3 parts, and lubricant 0.1-0.3 parts.

7. The thermally conductive polypropylene composite material suitable for high power LED luminaire heat sink device according to claim 6, characterized in that, The primary antioxidant is antioxidant 1010; The secondary antioxidant is antioxidant 168; The lubricant is ethylene bis-stearamide.

8. The method according to any one of claims 1 to 7, characterized in that, Comprising: Mixing the raw materials except the reinforcing agent, adding them to the main feeding port of the double-screw extruder, adding the reinforcing agent to the exhaust port of the double-screw extruder, and then melting, extruding, cooling, and drying to obtain the thermal conductive polypropylene composite material suitable for high-power LED lamp heat dissipation devices.

9. The production method according to claim 8, characterized by, The temperature of each partition of the barrel of the double-screw extruder is maintained at 160-230℃, and the screw rotation speed is 300-400 rpm; The preparation method further includes granulation after drying, and the thermal conductive polypropylene composite material suitable for high-power LED lamp heat dissipation devices is in the form of granules.

10. The thermal conductive polypropylene composite material according to any one of claims 1-7 for use in the manufacture of high-power LED lamp heat dissipation devices.

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