Preparation method of interior heating product based on graphene

Abstract

The invention discloses a preparation method of an interior heating product based on graphene, which comprises the following steps: step 1, cutting a graphene heating pad into a shape matched with that of an injection mold, and hanging the cut graphene heating pad on a hanging needle of the injection mold; wherein the structure of the graphene heating pad is rectangular, and the size of the graphene heating pad is 300mm * 200mm; 2, injection molding equipment is started, plastic in a molten state at the temperature of 160-240 DEG C is injected into the mold cavity within 1-5 S through a pouring gate with the caliber not larger than 5 mm < 2 > under the pressure of 0.5-10 MPa, injection molding is conducted, and a graphene heating product is obtained; wherein the plastic is a high polymer material. The graphene heating pad is integrated with the plastic part through injection molding, so that the obtained integrated part has an electric heating function, heating is uniform, the environmental protection property is good, procedures are saved, and the machining efficiency is improved.

Description

Technical Field

[0001] The present invention relates to a preparation method of an interior heating product based on graphene, belonging to the technical field of vehicle interiors and seat peripheries. Background Art

[0002] With the continuous growth of people's personalized needs for automotive products, the design and production of automobiles and their internal components also show diverse functional characteristics. As an automotive product component that directly contacts the human body, the car seat needs to have good safety, comfort, and environmental friendliness.

[0003] Graphene material is a honeycomb structure composed of six-ring materials, and it is a lightweight material with good functional characteristics emerging in recent years. Graphene material has better heat-up performance than resistance wires. Graphene plays a role in quickly and evenly transferring heat in the graphene heating pad, making the graphene heating pad have better thermal uniformity, and the graphene heating pad can meet the optimized design requirements of car seats.

[0004] The process of existing graphene heating products is as follows: spraying glue - drying - pre-positioning - edge wrapping - trimming - lamination on the graphene heating pad and the skeleton substrate to complete the integration of the graphene heating pad and the skeleton substrate.

[0005] Since the integration process of the graphene product and the skeleton includes processes such as spraying glue, drying, pre-positioning, and lamination, it is equivalent to adding processes and operations related to the integration of the graphene heating product and the skeleton to the original processes and equipment investment, thus increasing the manufacturing cost and investment significantly. Moreover, the graphene heating products made by the existing preparation process have poor visual effects and strong product odors. Summary of the Invention

[0006] The present invention designs and develops a preparation method of an interior heating product based on graphene, integrating the graphene heating pad and the plastic part by injection molding to improve its environmental performance and reduce processing steps.

[0007] The technical solution provided by the present invention is as follows:

[0008] A preparation method of an interior heating product based on graphene, comprising:

[0009] Step 1: Cut the graphene heating pad, and hang the cut graphene heating pad on the hanging pins of the injection mold.

[0010] Step 2: Start the injection molding equipment, and inject the molten plastic into the mold cavity of the injection mold under pressure conditions to perform injection molding to obtain the graphene heating product.

[0011] Preferably, the Step 2 includes:

[0012] The molten plastic is injected into the mold cavity under a pressure of 0.5 - 10 MPa through a gate with a diameter not greater than 5 mm 2 within 1 - 5 seconds for injection molding.

[0013] Preferably, the temperature of the molten plastic is 160 - 240 °C.

[0014] Preferably, the graphene heating pad has a seven - layer structure. The overall structure of the graphene heating pad is: encapsulation cloth layer, PI film layer, graphene layer, conductive cloth layer, graphene layer, PI film layer, encapsulation cloth layer.

[0015] Preferably, the solid content of graphene in the graphene layer is 1%.

[0016] Preferably, the structure of the graphene heating pad is rectangular and matches the injection mold.

[0017] Preferably, the size of the graphene heating pad is: 300 mm × 200 mm.

[0018] Preferably, during the injection molding process, the plastic is a polymer material.

[0019] The beneficial effects of the present invention are as follows:

[0020] The preparation method of the interior heating product based on graphene provided by the present invention integrates the graphene heating pad and the plastic skeleton substrate through injection molding and applies it to the back panel of the car seat or other automotive parts, which can improve the environmental performance, save multiple preparation processes, reduce the investment in labor and equipment, and improve the production efficiency of the graphene heating product. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the interior heating product based on graphene of the present invention.

[0022] Figure 2(a) is a picture of a product with heating product imprints on the surface without using this preparation process.

[0023] Figure 2(b) is a picture of a product without heating imprints on the surface obtained by using this preparation process. DETAILED DESCRIPTION OF THE INVENTION

[0024] The following further describes the present invention in detail with reference to the drawings so that those skilled in the art can implement it according to the description in the specification.

[0025] As Figure 1As shown in FIG. -2, the present invention provides a method for preparing an interior heating product based on graphene. By combining a graphene heating pad with a polymer plastic to form an integrated component, the resulting product has the effects of electric heating, uniform heating, good environmental protection, fewer processes, and improved processing efficiency. The method includes:

[0026] Step 1: Cut the graphene heating pad into a shape matching the injection mold, and hang the cut graphene heating pad on the hanging pins of the injection mold.

[0027] Among them, in the present invention, as a preference, the structure of the graphene heating pad is rectangular, with dimensions of 300 mm × 200 mm.

[0028] Step 2: Start the injection molding equipment. Inject the plastic in a molten state at a temperature of 160 - 240 °C under a pressure of 0.5 - 10 MPa through a gate with a diameter not greater than 5 mm 2 into the mold cavity within 1 - 5 s for injection molding to obtain a graphene heating product.

[0029] Among them, the plastic used is a polymer material. In the present invention, as a preference, PP + EPDM - T20 plastic is selected.

[0030] The structure of the obtained graphene heating product includes: a skeleton layer 100 and a graphene heating pad layer 200, where the skeleton layer is an injection molded layer.

[0031] In the present invention, as a preference, the graphene heating pad has a seven - layer structure, including: two encapsulation cloth layers, two PI film layers, two graphene layers, and one conductive cloth layer.

[0032] Among them, with the conductive cloth as the middle layer, graphene layers, PI film layers, and encapsulation cloth layers are symmetrically arranged on both sides in sequence, so that the overall structure of the graphene heating pad is: encapsulation cloth layer, PI film layer, graphene layer, conductive cloth layer, graphene layer, PI film layer, encapsulation cloth layer. In the graphene layer, the solid content of graphene is 1%.

[0033] Example 1

[0034] Integrate the graphene heating pad with the backrest of an automotive seat. Through the injection molding process, a heated seat backrest is obtained, which specifically includes:

[0035] Cut the graphene heating pad into a rectangular shape with a length of 300 mm and a width of 200 mm. Hang the cut heating pad on the hanging pins of the injection mold. Start the injection molding equipment for the seat backrest. Use PP + EPDM - T20 plastic in a molten state at 200 °C under a pressure of 6 MPa through a gate with a diameter not greater than 5 mm 2The gate injects into the mold cavity within 3S for injection molding to obtain a graphene heating product.

[0036] Example 2

[0037] Integrate the graphene heating pad with the automotive seat back panel. Through the injection molding process, a heated seat back panel is obtained, specifically including:

[0038] Cut the graphene heating pad into a rectangular shape with a length of 300mm and a width of 200mm. Hang the cut heating pad on the hanging pins of the injection mold, start the injection molding equipment for the seat back panel, and use PP+EPDM-T20 plastic in a molten state at 240°C under a pressure of 10MPa. Through a gate with a diameter not exceeding 5mm 2 inject into the mold cavity within 5S for injection molding.

[0039] Example 3

[0040] Integrate the graphene heating pad with the automotive seat back panel. Through the injection molding process, a heated seat back panel is obtained, specifically including:

[0041] Cut the graphene heating pad into a rectangular shape with a length of 300mm and a width of 200mm. Hang the cut heating pad on the hanging pins of the injection mold, start the injection molding equipment for the seat back panel, and use PP+EPDM-T20 plastic in a molten state at 160°C under a pressure of 0.5MPa. Through a gate with a diameter not exceeding 5mm 2 inject into the mold cavity within 1S for injection molding.

[0042] Comparative Example

[0043] Glue spraying on the graphene heating pad and the skeleton - drying of the graphene heating pad and the skeleton - pre - positioning and covering of the graphene heating pad and the skeleton - edge binding of the graphene heating pad and the skeleton - hot - pressing and compounding of the graphene heating pad and the skeleton; the above description completes the integration of the graphene heating material and the skeleton substrate.

[0044] Test the graphene heating products prepared in Examples 1 - 3 and the comparative example. The test contents include:

[0045] High - temperature resistance test: 90±2°C, storage for 24h;

[0046] Cold resistance test: - 40±2°C, storage for 24h;

[0047] High - low temperature and humidity alternating test:

[0048] a. 40±1°C, 95±5%RH, 14h;

[0049] b. - 40±2°C, 4h;

[0050] c. 85 ± 2 °C, 6 h;

[0051] a - c is one cycle, with a total of 20 cycles;

[0052] Hot air aging test: 80 ± 2 °C, stored for 700 ± 2 h;

[0053] Peel strength test, including: ①. After the supply state ②. After hot air aging ③. After high and low temperature humidity cycling ④. After low temperature resistance;

[0054] Odor test: Test temperature 80 ± 2 °C, time: 2 h 10 min;

[0055] Epidermal yellowing experiment: Power on for 10 h, power off for 14 h, cycle test for 30 d;

[0056] Plastic part deformation test: Power on for 10 h, power off for 14 h, cycle test for 30 d;

[0057] Performance decay test: Power on for 10 h, power off for 14 h, cycle test for 30 d.

[0058] The test results are shown in Table 1:

[0059] Table 1

[0060]

[0061] Among them, the specific odor test includes:

[0062] Take 20 g of sample strips from the obtained product and put them into an odor bottle. At the test temperature of 80 ± 2 °C, after storage for 2 h, cool it to 60 ± 5 °C, and then conduct odor level evaluation; the evaluation is carried out by a group of personnel recognized by odor training, including:

[0063] Open one side of the odor bottle cap by 3 - 4 cm, keep the evaluator's nose 2 - 3 cm away from the bottle mouth, and multiple evaluators sniff one by one and conduct odor evaluation; the passing standard is ≤ 3 levels. Among them, level 1 means no odor and is not easily felt; level 2 means there is an odor, which can be felt, with a slight intensity; level 3 means there is an obvious odor, which can be clearly felt, with a medium intensity; level 4 means there is an obvious odor, with a large intensity; level 5 means there is an obvious odor, with a very large intensity; level 6 means an intolerable odor.

[0064] Odor test results:

[0065] Control example: Take sample strips from the whole product, odor = 3.5 levels.

[0066] Example 1: Take sample strips from the whole product, odor = 2.5 levels.

[0067] Example 2: Take sample strips from the whole product, odor = 2.5 levels.

[0068] Example 3: The whole piece is sampled, and the odor is Grade 2.5.

[0069] From the comparative examples, Examples 1 to 3 and the above test results, it can be seen that the products prepared by the preparation method of the graphene heating product provided by the present invention can save several preparation processes in the preparation process, which means that a large amount of labor, material and time costs can be saved, and the production efficiency can be greatly improved. And it can be seen from Table 1 that the performance of the products prepared by this method can reach the performance of existing products, and even in terms of odor, it is better than the products prepared by the comparative example, improving the environmental protection of the products.

[0070] At the same time, due to the injection molding method of the graphene heating pad, the seat back panel products prepared by the preparation process provided by the present invention have no marks on the whole, improving the visual effect during use, as shown in Figure 2(b). However, for the seat back panel using the existing skin + heating pad + skeleton wrapping integration, there will be a problem of product surface imprints in the shape of electrodes on the product surface after processing, as shown in Figure 2(a).

[0071] Although the embodiments of the present invention have been disclosed as above, it is not limited to the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to the specific details and the examples shown and described here.

Claims

1. A method for preparing a graphene-based interior heating product, characterized in that: include: Step 1: Cut the graphene heating pad and hang the cut graphene heating pad on the hanging pin of the injection mold; Step 2: Start the injection molding equipment, inject the molten plastic into the mold cavity of the injection mold under pressure, perform injection molding, and obtain the graphene-based interior heating product.

2. The method for preparing a graphene-based interior heating product according to claim 1, characterized in that: The second step comprises: The molten plastic passes through a hole with a diameter of no more than 5 mm under a pressure of 0.5-10 MPa. 2 The material is injected into the mold cavity within 1 to 5 seconds for injection molding.

3. The method for preparing a graphene-based interior heating product according to claim 2, characterized in that: The temperature of the molten plastic is 160-240°C.

4. The method for preparing a graphene-based interior heating product according to claim 3, characterized in that: The graphene heating pad has a seven-layer structure, and the overall structure of the graphene heating pad is: packaging cloth layer, PI film layer, graphene layer, conductive cloth layer, graphene layer, PI film layer, and packaging cloth layer.

5. The method for preparing a graphene-based interior heating product according to claim 4, characterized in that: The solid content of graphene in the graphene layer is 1%.

6. The method for preparing a graphene-based interior heating product according to claim 5, characterized in that: The graphene heating pad has a rectangular structure that matches the injection mold.

7. The method for preparing a graphene-based interior heating product according to claim 6, characterized in that: The size of the graphene heating pad is: 300mm×200mm.

8. The method for preparing a graphene-based interior heating product according to claim 7, characterized in that: During the injection molding process, the plastic is a polymer material.

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