阅读说明：本技术 一种pp/pe/bn/epdm导热绝缘材料及其制备方法 (PP/PE/BN/EPDM heat-conducting insulating material and preparation method thereof ) 是由 李迎春 常磊 畅贝哲 杜拴丽 王文生 安超 朱家华 于 2020-06-19 设计创作，主要内容包括：本发明属于高分子材料中的导热绝缘材料领域,涉及PP/PE共连续结构和导热绝缘材料,特别涉及一种PP/PE/BN/EPDM导热绝缘材料及其制备方法。BN、EPDM干燥后进行熔融共混挤出造粒,得到预制BN/EPDM共混物,PP、PE干燥后与预制BN/EPDM共混物进行熔融共混挤出造粒、干燥和注塑,得到PP/PE/BN/EPDM导热绝缘复合材料。实验结果表明,本申请提供母料共混法下,添加10份BN的PP/PE/BN/EPDM复合材料的热导率比不添加BN的PP/PE/EPDM复合材料的热导率提高了56.3%；在添加10份BN的PP/PE/BN/EPDM复合材料中,母料共混法比直接共混法的热导率提高了36.9％。本发明的制备方法可将大大提高复合材料的导热性,具有较高市场价值。(The invention belongs to the field of heat-conducting insulating materials in high polymer materials, relates to a PP/PE co-continuous structure and a heat-conducting insulating material, and particularly relates to a PP/PE/BN/EPDM heat-conducting insulating material and a preparation method thereof. And drying the BN and the EPDM, then carrying out melt blending extrusion granulation to obtain a prefabricated BN/EPDM blend, drying the PP and the PE, and then carrying out melt blending extrusion granulation, drying and injection molding on the PP and the PE and the prefabricated BN/EPDM blend to obtain the PP/PE/BN/EPDM heat-conducting and insulating composite material. Experimental results show that under the master batch blending method provided by the application, the thermal conductivity of the PP/PE/BN/EPDM composite material added with 10 parts of BN is improved by 56.3 percent compared with that of the PP/PE/EPDM composite material not added with BN; in the PP/PE/BN/EPDM composite material added with 10 parts of BN, the thermal conductivity of the master batch blending method is improved by 36.9 percent compared with that of a direct blending method. The preparation method can greatly improve the thermal conductivity of the composite material and has higher market value.)

1. A PP/PE/BN/EPDM heat-conducting insulating material is characterized by being prepared from the following raw materials in parts by weight,

10 parts of EPDM (ethylene-propylene-diene monomer),

BN is 0 to 10 parts and is not 0,

50 parts of HDPE (high-density polyethylene),

and 50 parts of PP.

2. A PP/PE/BN/EPDM thermal insulation material as claimed in claim 1, wherein said PP melt index is 2.9g/10 min.

3. The PP/PE/BN/EPDM thermally conductive and insulating material as claimed in claim 1, wherein said HDPE has a melt index of 20g/10 min.

4. The PP/PE/BN/EPDM thermal conductive and insulating material as claimed in claim 1, wherein the particle size of BN is 10 μm or less.

5. The PP/PE/BN/EPDM thermally conductive and insulating material as claimed in claim 1, wherein the EPDM has a propylene content of 29.5wt% and an ethylene content of 70%.

6. A method for preparing PP/PE/BN/EPDM heat-conducting insulating material, which is characterized in that the raw material as claimed in any one of claims 1 to 5 is adopted, and the method comprises the following steps: and drying the BN and the EPDM, then carrying out melt blending extrusion granulation, obtaining a prefabricated BN/EPDM blend by a master batch blending method, drying the PP and the PE, and carrying out melt blending extrusion granulation, drying and injection molding on the prefabricated BN/EPDM blend to obtain the PP/PE/BN/EPDM heat-conducting and insulating composite material.

7. The method for preparing a PP/PE/BN/EPDM thermal conductive insulating material as claimed in claim 6, wherein the melt blending extrusion granulation is performed in a micro twin-screw extruder, the temperature of each section from one section to the head is 180 ℃, 190 ℃, 200 ℃ and 190 ℃, respectively, and the screw rotating speed of the micro twin-screw extruder is 80 r/min.

8. The method of claim 6, wherein the injection molding is performed in a micro injection molding machine, the mold temperature of the micro injection molding machine is 60 ℃, the cylinder temperature is 190 ℃, the injection pressure is 0.3MPa and 0.6MPa, and the injection time is 3s and 40s, respectively.

Technical Field

The invention belongs to the field of heat-conducting insulating materials in high polymer materials, relates to a PP/PE co-continuous structure and a heat-conducting insulating material, and particularly relates to a PP/PE/BN/EPDM heat-conducting insulating material and a preparation method thereof.

Background

In the heat-conducting insulating material controlled by the microstructure, if a continuous phase can be formed under the condition of low minority phase content, the filler is effectively connected and uniformly distributed in the minority phase, the lower the content of the heat-conducting filler required under the same heat conductivity is, and the prepared low-filling high-heat-conducting material has the characteristics of light weight, corrosion resistance, insulation, excellent heat-conducting property and the like, and can be applied to new materials such as solar cells, LED lamp shells, integrated circuits, CPU processors and the like.

The thermal conductivity of filled polymer materials depends on both the distribution of the filler and the matrix-filler interfacial thermal resistance. When a small amount of filler is used as a dispersed phase, the filler is mutually dispersed and cannot be connected in series to form a passage, and the heat-conducting property of the composite material is difficult to improve. Only when the filler is sufficient and can be mutually overlapped to form a heat-conducting network, if the filler filling amount is continuously increased, the heat-conducting networks are mutually penetrated, and the heat-conducting performance of the system is suddenly improved. Since the thermal conductive filler is much larger than the thermal conductivity of the matrix resin, phonons are scattered at the interface between the two. Poor bonding, voids, defects, and the like exist at the interface, which aggravates the scattering phenomenon and thus increases the thermal resistance of the two-phase interface.

According to the heat conduction mechanism, the heat conductivity of the composite material is improved, on the basis of forming a co-continuous structure, if the distribution of the filler at a phase interface can be controlled and the filler can be effectively connected, less heat conduction filler can be used for achieving higher heat conductivity, and the prepared low-content high-heat-conduction material has the characteristics of light weight, corrosion resistance, insulation, excellent heat conduction performance and the like.

Disclosure of Invention

The invention provides a PP/PE/BN/EPDM heat-conducting and insulating material and a preparation method thereof, aiming at solving the defect of low heat conductivity under the condition of low filling content of heat-conducting filler.

The invention is realized by the following technical scheme: a PP/PE/BN/EPDM heat-conducting insulating material is prepared from the following raw materials in parts by weight,

10 parts of EPDM (ethylene-propylene-diene monomer),

0 to 10 parts of BN (boron nitride) other than 0,

50 parts of HDPE (high-density polyethylene),

50 parts of PP (polypropylene).

As a further improvement of the technical scheme of the invention, the melt index of the PP is 2.9g/10 min.

As a further improvement of the technical scheme of the invention, the HDPE has a melt index of 20g/10 min.

As a further improvement of the technical scheme of the invention, the particle size of the BN is less than or equal to 10 microns.

As a further improvement of the technical scheme of the invention, the EPDM has the propylene content of 29.5wt% and the ethylene content of 70%.

The invention further provides a preparation method of the PP/PE/BN/EPDM heat-conducting and insulating material, which adopts the raw materials and comprises the following steps: and drying the BN and the EPDM, then carrying out melt blending extrusion granulation, obtaining a prefabricated BN/EPDM blend by a master batch blending method, drying the PP and the PE, and carrying out melt blending extrusion granulation, drying and injection molding on the prefabricated BN/EPDM blend to obtain the PP/PE/BN/EPDM heat-conducting and insulating composite material.

Through the blending sequence, the rubber elastomer EPDM is adopted to wrap the heat-conducting filler BN, the melt blending is carried out on the BN/EPDM blend prefabricated by PP, PE and a master batch blending method, the positioning of the heat-conducting filler BN at a phase interface is realized by the action mechanism of the compatilizer EPDM of the high-density polyethylene and polypropylene blend at the phase interface, and then the heat-conducting filler BN is contacted with each other at the phase interface to form a heat-conducting passage with a microstructure, so that the heat conductivity of the composite material is improved. In the transverse and longitudinal directions of the invention, the co-continuous structure of the composite material is obtained by blending high-density polyethylene and polypropylene in the same proportion.

As a further improvement of the technical scheme of the preparation method, the melt blending extrusion granulation is operated in a miniature double-screw extruder, and the temperatures of all sections from one section to a machine head are respectively 180 ℃, 190 ℃, 200 ℃ and 190 ℃. The screw rotating speed of the double-screw extruder is 80 r/min.

As a further improvement of the technical scheme of the preparation method, the injection molding is carried out in a micro injection molding machine, the mold temperature of the micro injection molding machine is 60 ℃, the temperature of a charging barrel is 190 ℃, the injection molding pressure is 0.3MPa and 0.6MPa respectively, and the injection molding time is 3s and 40s respectively.

The heat-conducting and insulating PP/PE/BN/EPDM material of the invention adds BN into EPDM, the market price of PE plastic is 8300 yuan/ton, and the market price of PP is 8500 yuan/ton; the EPDM has a market price of 20-30 yuan/kg, the BN has a market price of 1599 yuan/kg, and the PP/PE/BN/EPDM heat-conducting and insulating composite material with good heat-conducting property is prepared. Experimental results show that the heat conductivity of the PP/PE/BN/EPDM composite material added with 10 parts of BN under the master batch blending method provided by the application is improved by 56.3 percent compared with the heat conductivity of the PP/PE/EPDM composite material not added with BN; in the PP/PE/BN/EPDM composite material added with 10 parts of BN, the thermal conductivity of the master batch blending method is improved by 36.9 percent compared with that of a direct blending method. The preparation method can greatly improve the thermal conductivity of the composite material and has higher market value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a scanning electron microscope image of a PP/PE/BN/EPDM composite material with 10 parts of BN added by a master batch blending method, wherein etching phases are EPDM and BN, and a white line is a heat conduction path formed by the BN at a PP/PE phase interface.

FIG. 2 is a scanning electron microscope image of a PP/PE/BN/EPDM composite material with 10 parts of BN added by a direct blending method, and white lines are passages formed by EPDM etching phases.

As can be seen from a comparison of fig. 1 and 2: in the PP/PE/BN/EPDM composite material added with 10 parts of BN, the master batch blending method is easier to enable the composite material to form a heat conduction path than a direct blending method.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

The invention provides a PP/PE/BN/EPDM heat-conducting insulating material which is prepared from the following raw materials, by weight, 10 parts of EPDM (ethylene propylene rubber), 0-10 parts of BN (boron nitride) but not 0, 50 parts of HDPE (high density polyethylene) and 50 parts of PP (polypropylene).

The PP provided by the invention has the brand number of T30S, the manufacturer is China oil and gas Co., Ltd, and the melt index is 2.9g/10 min.

In one embodiment of the present invention, the HDPE brand is 2911, the manufacturer is China oil and gas products, Inc., and the melt index is 20g/10 min.

In one embodiment of the present invention, the EPDM, available from Shandong Yousio chemical technology, Inc., having a designation of 3745P, was manufactured by Dow chemical, having a propylene content of 29.5wt% and an ethylene content of 70%.

In one embodiment of the present invention, BN is 10043-11-5, and the manufacturer is Shanghai Aladdin Biotechnology Ltd, and the particle size is 10 μm or less.

The invention provides a preparation method of a PP/PE/BN/EPDM heat-conducting insulating material for realizing the positioning of a heat-conducting filler BN at a phase interface, which adopts the raw materials and comprises the following steps: and drying the BN and the EPDM, then carrying out melt blending extrusion granulation, obtaining a prefabricated BN/EPDM blend by a master batch blending method, drying the PP and the PE, and carrying out melt blending extrusion granulation, drying and injection molding on the prefabricated BN/EPDM blend to obtain the PP/PE/BN/EPDM heat-conducting and insulating composite material.

Specifically, the melt blending extrusion granulation is operated in a micro double-screw extruder, and the temperature of each section from one section to a machine head is 180 ℃, 190 ℃, 200 ℃ and 190 ℃. The screw rotating speed of the miniature double-screw extruder is 80 r/min.

Further, the injection molding is carried out in a micro injection molding machine, the mold temperature of the micro injection molding machine is 60 ℃, the temperature of the charging barrel is 190 ℃, the injection molding pressure is 0.3MPa and 0.6MPa respectively, and the injection molding time is 3s and 40s respectively.

In addition, in an embodiment of the present invention, the micro twin-screw extruder was manufactured by warhamr ringing laboratory instruments ltd, model: JSZS-10B, a mini injection molding machine is manufactured by Wuhan Ruizi laboratory instruments GmbH, model: SZS-20.

The technical solution of the present invention will be described below by way of specific examples.