Preparation method of polymer-based heat-conducting intelligent material for thermal interface

Abstract

The invention discloses a preparation method of a polymer-based heat-conducting intelligent material for a thermal interface, and the preparation method of the polymer-based heat-conducting intelligent material for the thermal interface comprises the following steps: 1) preparation of poly (MMAx-PDMS): adding methyl methacrylate (MMA) and polydimethylsiloxane (PDMS) into N, N-dimethylformamide (DMF), and uniformly mixing; adding dimethyl azodiisobutyrate (AIBME) into the mixture, uniformly mixing, and reacting for a period of time in a nitrogen environment; after the reaction is finished, a reaction product is precipitated in silicone oil, and an unMMA-PDMS polymer which is called poly (MMAx-PDMS) is obtained; and (2) preparation of poly (MMAx-PDMS) / VAFG (vinyl acetate fiber glass).

Description

Technical Field

[0001] The present invention relates to a polymer-based thermally conductive intelligent material preparation technology for thermal interface, which can be used for electronic equipment, battery thermal management, and thermal interface of flexible electronic devices. It has broad prospects in the field of intelligent thermal management and belongs to the field of polymer functional composite materials. Background Art

[0002] Smart materials are a new type of material that can sense changes in the environment and respond accordingly. They are usually made of advanced polymers, metals, ceramics or composites, and integrate sensors, actuators and control systems. These materials can change their physical or chemical properties in response to external stimuli such as temperature, pressure, humidity, light or electric fields. For example, some smart materials can become soft when heated or harden when cooled, and some can change color or transparency when exposed to light. The applications of smart materials are very wide, including but not limited to medical devices, aerospace, construction, automotive industry and electronics. In the medical field, they can be used to make degradable stents or drug release systems; in the aerospace field, smart materials can be used to make self-healing aircraft parts; in architecture, they can be used to make smart windows that can regulate indoor temperature. These characteristics of smart materials make them play an increasingly important role in modern technology and promote innovation in materials science and engineering.

[0003] Thermally conductive materials are a class of materials with efficient heat conduction properties, which means they can quickly transfer heat from one point to another. These materials usually have high thermal conductivity, which means they perform well in thermal management and are widely used in various industrial and commercial fields to optimize the transmission and distribution of thermal energy. The composition of thermally conductive materials can be metal, ceramic, polymer-based composites or carbon materials, such as copper, aluminum, graphene, carbon fiber and certain engineering plastics. Metal thermal conductive materials are popular for their high thermal conductivity, but they can be heavy and costly. In contrast, although ceramic thermal conductive materials may have slightly lower thermal conductivity, they provide better thermal and chemical stability. Polymer-based composites improve their thermal conductivity properties by adding thermally conductive fillers (such as metal particles or carbon materials) while maintaining the light weight and processability of the polymer. Thermally conductive materials are used in a wide range of applications, including heat dissipation solutions for electronic devices, such as heat sinks in smartphones, computers, and LED lighting; in the aerospace field, they are used to protect sensitive electronic devices from overheating; in the automotive industry, they are used to dissipate heat from engine components; in the construction industry, they are used as thermal insulation materials to improve energy efficiency; and in sports equipment to improve athlete comfort and performance. As technology develops, thermally conductive materials are also constantly innovating, such as improving their thermal conductivity through nanotechnology, or developing new composite materials to meet the needs of specific applications. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing a polymer-based thermally conductive smart material for a thermal interface, wherein the prepared smart thermally conductive composite material has a heat sensing function. The technical solution of the present invention is as follows:

[0005] 1. A method for preparing a polymer-based thermally conductive smart material for a thermal interface, comprising the following steps:

[0006] 1) Preparation of poly(MMAx-PDMS): Methyl methacrylate (MMA) and polydimethylsiloxane (PDMS) in a molar ratio of 1:0.8-1.2 are added to N,N-dimethylformamide (DMF) and mixed uniformly at 50° C.; 0.4-0.6% of dimethyl azobisisobutyrate (AIBME) is added to the above mixture in an amount of 1:0.8-1.2% of the total molar amount of the monomers, and the mixture is mixed uniformly and reacted at 75-80° C. in a nitrogen environment for a period of time; after the reaction is completed, the reaction product is precipitated in silicone oil to obtain a non-MMA-PDMS polymer, which is referred to as poly(MMAx-PDMS);

[0007] 2) Preparation of poly (MMAx-PDMS) / VAFG: Poly (MMAx-PDMS) is fully dissolved in ethyl acetate solution to obtain a polymer solution, and the polymer solution is filled into the gaps of the graphene array VAFG using a vacuum impregnation process, dried at room temperature for a period of time, and then dried at 55°C under vacuum conditions for a longer time; the above process is repeated many times until the gaps of VAFG are completely filled, and finally the poly (MMAx-PDMS) / VAFG smart sensing thermal conductive material is obtained.

[0008] The poly (MMAx-PDMS) / VAFG intelligent sensing thermal conductive material prepared by the present invention has high resilience, high thermal conductivity, and strong interface adhesion, and is expected to be used in intelligent thermal management fields such as human body, artificial intelligence, and electronic information. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Schematic diagram of poly(MMAx-PDMS) / VAFG.

[0010] Figure 2 Schematic diagram of heat transfer at the thermal interface of poly(MMAx-PDMS) / VAFG.

[0011] Figure 3 It is the intelligent thermal control map. DETAILED DESCRIPTION

[0012] The following is a preferred embodiment of the present invention, which is intended to further illustrate the present invention but not to limit the scope of the present invention.

[0013] 1) Preparation of poly(MMAx-PDMS): First, methyl methacrylate (MMA) and polydimethylsiloxane (PDMS) in a molar ratio of 1:1 were added to an appropriate amount of N,N-dimethylformamide (DMF) and stirred evenly at 50°C for 2 hours. Then, dimethyl azobisisobutyrate (AIBME) accounting for about 0.5% of the total molar amount of the monomers was added to the above mixture, mixed evenly, and reacted at 77°C under nitrogen (N2) for 12 hours. After the reaction was completed, the reaction product was precipitated in silicone oil to obtain MMA-PDMS polymer (referred to as poly(MMAx-PDMS)).

[0014] 2) Preparation of poly(MMAx-PDMS) / VAFG: 15g of poly(MMAx-PDMS) was fully dissolved in 50g of ethyl acetate solution to obtain a polymer solution, and then the polymer solution was filled into the gaps of the graphene array VAFG by vacuum impregnation process, dried at room temperature for 6h, and then dried at 55°C under vacuum conditions for 48h. The above process was repeated many times until the gaps of VAFG were completely filled, and finally the poly(MMAx-PDMS) / VAFG smart sensing thermal conductive material was obtained.

[0015] PDMS is a polymer with excellent flexibility and elasticity, with low single-chain elasticity and large cross-sectional area, as well as weak intra-chain / inter-chain interactions. These factors make the PDMS macroscopic material have a relatively small elastic modulus, thus showing high elasticity. Poly (MMAx-PDMS) can combine the rigid characteristics of MMA and the flexibility of PDMS to optimize the mechanical properties of the material. The rigidity provided by MMA can enhance the overall strength of the material, while PDMS provides flexibility and elasticity. The combination of the two makes the copolymer have better resilience. VAFG (vertically aligned graphene array) is a material with high thermal conductivity, which can provide an efficient heat conduction path for composite materials, thereby improving the thermal conductivity of the overall material. At the same time, the strong interfacial adhesion between poly (MMAx-PDMS) and VAFG helps to ensure that heat is effectively transferred between the material and the contact surface, reducing thermal resistance. The poly (MMAx-PDMS) / VAFG prepared by the present invention has both high resilience and high thermal conductivity, and can be used for thermal management of electronic devices or human bodies.

[0016] The present invention is described above by way of example. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent replacement that can be made by those skilled in the art without inventive effort falls within the protection scope of the present invention.

Claims

1. A method for preparing a polymer-based thermally conductive smart material for a thermal interface, comprising the following steps: 1) Preparation of poly(MMAx-PDMS): Methyl methacrylate (MMA) and polydimethylsiloxane (PDMS) in a molar ratio of 1:0.8-1.2 are added to N,N-dimethylformamide (DMF) and mixed evenly; 0.4-0.6% of dimethyl azobisisobutyrate (AIBME) is added to the above mixture, and after mixing evenly, the mixture is reacted at 75-80° C. under a nitrogen environment for a period of time; after the reaction is completed, the reaction product is precipitated in silicone oil to obtain a non-MMA-PDMS polymer, which is called poly(MMAx-PDMS); 2) Preparation of poly (MMAx-PDMS) / VAFG: Poly (MMAx-PDMS) is fully dissolved in ethyl acetate solution to obtain a polymer solution, and the polymer solution is filled into the gaps of the graphene array VAFG using a vacuum impregnation process, dried at room temperature for a period of time, and then dried for a longer time under vacuum conditions below 55°C; the above process is repeated many times until the gaps of VAFG are completely filled, and finally the poly (MMAx-PDMS) / VAFG smart sensing thermal conductive material is obtained.

2. The preparation method according to claim 1, characterized in that After uniform mixing in step 1), the mixture is reacted at 77° C. in a nitrogen environment for a period of time.

3. The preparation method according to claim 1, characterized in that In step 2), the room temperature is controlled at 25-28°C.

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