Low-VOC (volatile organic compound) automotive interior material and preparation process thereof

Abstract

The invention belongs to the technical field of automotive interior materials, and particularly relates to a low-VOC automotive interior material and a preparation process thereof. The material is prepared from the following raw materials in parts by weight: 80 to 90 parts of polyether polyol, 100 to 110 parts of toluene diisocynate, 10 to 15 parts of epoxy resin, 5 to 8 parts of terephthalic acid, 0.5 to 1 part of Zn modified graphene, 3 to 5 parts of water, 1 to 3 parts of foaming agent and 0.1 to 0.5 part of bismuth isooctoate. In the process of generating polyurethane through the reaction of polyether polyol and isocyanate, the epoxy resin, terephthalic acid and Zn modified graphene are used as auxiliaries, so that excellent mechanical properties can be obtained, volatilization of VOC molecules can be effectively reduced, and the polyurethane material is safer and more environmentally friendly and has a wide market prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile interior decoration materials, and specifically relates to a low-VOC automobile interior decoration material and a preparation process thereof. Background Art

[0002] In recent years, the emission of volatile organic compounds (VOC) in automobiles has attracted great attention from the world's automobile manufacturing industry. Most automobile interior parts contain a certain amount of VOC, and the content of benzene, aldehydes, and benzene-olefins in the VOC of interior parts is in excess of the standard, among which aldehydes are the most harmful to the human body. With the enhancement of people's environmental awareness, the requirements for the VOC content of automobile interior parts are becoming more and more stringent. At present, the removal of VOC substances in automobile interiors has become a technical problem.

[0003] Polyurethane materials are widely used in automotive interiors, and are often used in car sunroof visors and roofs. Polyurethane materials are generally made by reacting a polyol composition with an isocyanate composition in the presence of a catalyst, silicone oil, etc., but the aldehyde index of the product VOC is particularly difficult to control. In order to improve the odor and VOC emissions of polyurethane materials, researchers have done a lot of work, such as reducing the aldehyde content of the polyether itself, developing low-volatility catalysts and additives, etc. Although the volatilization of VOC has been controlled to a certain extent, the effect is still unsatisfactory and currently still cannot meet actual requirements. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a low-VOC automotive interior material and a preparation process thereof. In the process of generating polyurethane by reacting polyether polyol with isocyanate, epoxy resin, terephthalic acid and Zn-modified graphene are used as additives, which can not only obtain excellent mechanical properties but also effectively reduce the volatilization of VOC molecules, making it safer and more environmentally friendly, and has broad market prospects.

[0005] The first aspect of the present invention provides a low VOC automotive interior material, comprising the following raw materials in parts by weight: 80-90 parts of polyether polyol, 100-110 parts of toluene diisocyanate, 10-15 parts of epoxy resin, 5-8 parts of terephthalic acid, 0.5-1 part of Zn-modified graphene, 3-5 parts of water, 1-3 parts of foaming agent, and 0.1-0.5 parts of bismuth isooctanoate.

[0006] Furthermore, the preparation method of Zn-modified graphene includes: Mixing graphene and acetic acid, heating at 60-80°C for 3-4 hours for acidification, filtering, washing and drying to obtain acidified graphene; Zinc acetate is dissolved in ethylene glycol to form an impregnation solution, and then the acidified graphene is dispersed in the impregnation solution, and placed in a constant temperature water bath at 60-80° C. and heated and stirred for 6-8 hours to obtain Zn-modified graphene.

[0007] Furthermore, the addition ratio of graphene to acetic acid is 0.1~0.5g:50~60mL.

[0008] Furthermore, the addition ratio of the acidified graphene, zinc acetate and ethylene glycol is 0.1~0.2g:0.01mol:30~50mL.

[0009] Furthermore, the polyether polyol is at least one of CHE-828D, CHE-330N, and TEP3600.

[0010] Furthermore, the foaming agent is at least one of n-pentane, isopentane, cyclopentane, hexane, isohexane and cyclohexane.

[0011] Furthermore, the low-VOC automobile interior material also includes a foam stabilizer, carboxymethyl cellulose, whose mass is half that of the foaming agent.

[0012] The second aspect of the present invention provides a process for preparing the above-mentioned low-VOC automotive interior material, comprising the following steps: S1: Mix polyether polyol, epoxy resin and Zn-modified graphene evenly, perform high-pressure homogenization treatment, add foaming agent, bismuth isooctanoate and water, and perform ultrasonic stirring in a constant temperature water bath to form material A; S2: Mix toluene diisocyanate and terephthalic acid, and stir them ultrasonically in a constant temperature water bath to form material B; S3: Pour material B into material A quickly, stir at high speed for 8-10 seconds, then quickly pour into the foaming machine, vacuum degassing, open the mold after 4-5 minutes, take out and mature at room temperature for a period of time to obtain low VOC automotive interior material.

[0013] Furthermore, the pressure of the high-pressure homogenization treatment is 500~1000Bar, and the time of the high-pressure homogenization treatment is 10~15min.

[0014] Furthermore, the temperature of the constant temperature water bath is 25-30° C., and the ultrasonic stirring time is 20-30 min.

[0015] Further, the mixture is aged at room temperature for 60 to 72 hours.

[0016] The beneficial effects achieved by one or more technical solutions of the present invention are as follows: 1. The present invention first introduces Zn ions between the layers of graphene to effectively expand the interlayer distance of graphene, and under the homogenization of high pressure, the Zn-modified graphene is dispersed in the polyether polyol, and the interlayer force of the graphene is weakened, so that the graphene is gradually depolymerized and dispersed in the polyether polyol, and a strong van der Waals force can be generated between the graphene and the epoxy resin, thereby maintaining a good dispersed sheet state. This makes the product more stable in mechanical properties and more likely to form a loose and porous structure in the subsequent reaction of polyether polyol and toluene diisocyanate to generate polyurethane, thereby providing space for accommodating small VOC molecules.

[0017] 2. After terephthalic acid is introduced into the system, the Zn ions on the graphene surface and terephthalic acid can coordinate, thereby obtaining the ability to adsorb small VOC molecules. The unsaturated bonds on the surface of terephthalic acid and the epoxy resin can be oxidized and cross-linked to form a membrane network, making it difficult for the adsorbed VOC molecules to evaporate into the air, thereby effectively reducing VOC emissions. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in combination with specific embodiments and comparative examples.

[0019] Example 1 This embodiment provides a low-VOC automotive interior material, comprising the following raw materials in parts by weight: 80 parts of polyether polyol CHE-828D, 100 parts of toluene diisocyanate, 10 parts of epoxy resin, 5 parts of terephthalic acid, 0.5 parts of Zn-modified graphene, 3 parts of water, 2 parts of n-pentane, and 0.1 parts of bismuth isooctanoate; The preparation method is: S1: Graphene and acetic acid are mixed in an addition ratio of 0.1 g:50 mL, heated at 80° C. for 3 h for acidification, filtered, washed, and dried to obtain acidified graphene; Dissolve zinc acetate in ethylene glycol to form an impregnation solution, and then disperse the acidified graphene in the impregnation solution, wherein the addition ratio of the acidified graphene, zinc acetate and ethylene glycol is 0.1 g: 0.01 mol: 30 mL, and place the mixture in a constant temperature water bath at 80° C. and heat and stir for 8 hours to obtain Zn-modified graphene; S2: polyether polyol CHE-828D, epoxy resin and Zn-modified graphene are mixed evenly, and subjected to high-pressure homogenization treatment (the pressure of the high-pressure homogenization treatment is 1000 Bar, and the time of the high-pressure homogenization treatment is 10 minutes), and then n-pentane, bismuth isooctanoate and water are added, and ultrasonic stirring is carried out in a constant temperature water bath at 25°C for 30 minutes to form material A; S3: Toluene diisocyanate and terephthalic acid were mixed, and ultrasonically stirred in a constant temperature water bath at 25°C for 30 minutes to form material B; S4: Pour material B into material A rapidly, stir at high speed for 10 seconds, then quickly pour into a foaming machine, vacuum degas, open the mold after 5 minutes, take out and mature at room temperature for 72 hours to obtain a low VOC automotive interior material.

[0020] Example 2 This embodiment provides a low-VOC automotive interior material, comprising the following raw materials in parts by weight: 90 parts of polyether polyol CHE-330N, 110 parts of toluene diisocyanate, 15 parts of epoxy resin, 8 parts of terephthalic acid, 1 part of Zn-modified graphene, 5 parts of water, 3 parts of cyclopentane, and 0.5 parts of bismuth isooctanoate; The preparation method is: S1: Graphene and acetic acid are mixed in a ratio of 0.3 g:60 mL, heated at 80° C. for 3 h for acidification, filtered, washed, and dried to obtain acidified graphene; Dissolve zinc acetate in ethylene glycol to form an impregnation solution, and then disperse the acidified graphene in the impregnation solution, wherein the addition ratio of the acidified graphene, zinc acetate and ethylene glycol is 0.2 g: 0.01 mol: 50 mL, and place the mixture in a 60° C. constant temperature water bath and heat and stir for 8 h to obtain Zn-modified graphene; S2: Mix polyether polyol CHE-330N, epoxy resin and Zn-modified graphene evenly, perform high-pressure homogenization treatment (the pressure of high-pressure homogenization treatment is 1000 Bar, and the time of high-pressure homogenization treatment is 10 minutes), then add cyclopentane, bismuth isooctanoate and water, and stir ultrasonically in a constant temperature water bath at 30°C for 20 minutes to form material A; S3: Toluene diisocyanate and terephthalic acid were mixed, and ultrasonically stirred in a constant temperature water bath at 30°C for 20 minutes to form material B; S4: Pour material B into material A rapidly, stir at high speed for 10 seconds, then quickly pour into a foaming machine, vacuum degas, open the mold after 5 minutes, take out and mature at room temperature for 72 hours to obtain a low VOC automotive interior material.

[0021] Example 3 This embodiment provides a low-VOC automotive interior material, comprising the following raw materials in parts by weight: 85 parts of polyether polyol TEP3600, 100 parts of toluene diisocyanate, 12 parts of epoxy resin, 6 parts of terephthalic acid, 0.8 parts of Zn-modified graphene, 4 parts of water, 2 parts of isohexane, 1 part of carboxymethyl cellulose, and 0.2 parts of bismuth isooctanoate; The preparation method is: S1: Graphene and acetic acid are mixed in a ratio of 0.5 g:60 mL, heated at 80° C. for 3 h for acidification, filtered, washed, and dried to obtain acidified graphene; Dissolve zinc acetate in ethylene glycol to form an impregnation solution, and then disperse the acidified graphene in the impregnation solution, wherein the addition ratio of the acidified graphene, zinc acetate and ethylene glycol is 0.2 g: 0.01 mol: 50 mL, and place the mixture in a constant temperature water bath at 80° C. and heat and stir for 6 hours to obtain Zn-modified graphene; S2: Polyether polyol TEP3600, epoxy resin and Zn-modified graphene are mixed evenly, and subjected to high-pressure homogenization treatment (the pressure of the high-pressure homogenization treatment is 500 Bar, and the time of the high-pressure homogenization treatment is 15 minutes), and then isohexane, carboxymethyl cellulose, bismuth isooctanoate and water are added, and ultrasonic stirring is carried out in a constant temperature water bath at 25°C for 30 minutes to form material A; S3: Toluene diisocyanate and terephthalic acid were mixed, and ultrasonically stirred in a constant temperature water bath at 25°C for 30 minutes to form material B; S4: Pour material B into material A rapidly, stir at high speed for 8 seconds, then quickly pour into a foaming machine, vacuum degassing, open the mold after 4 minutes, take out and mature at room temperature for 70 hours to obtain a low VOC automotive interior material.

[0022] Example 4 This embodiment provides a low-VOC automotive interior material, comprising the following raw materials in parts by weight: 90 parts of polyether polyol CHE-828D, 110 parts of toluene diisocyanate, 12 parts of epoxy resin, 5 parts of terephthalic acid, 0.7 parts of Zn-modified graphene, 5 parts of water, 1 part of isopentane, and 0.3 parts of bismuth isooctanoate; The preparation method is: S1: Graphene and acetic acid are mixed in an addition ratio of 0.2 g:60 mL, heated at 60° C. for 4 h for acidification, filtered, washed, and dried to obtain acidified graphene; Dissolve zinc acetate in ethylene glycol to form an impregnation solution, and then disperse the acidified graphene in the impregnation solution, wherein the addition ratio of the acidified graphene, zinc acetate and ethylene glycol is 0.1 g: 0.01 mol: 50 mL, and place the mixture in a constant temperature water bath at 80° C. and heat and stir for 8 hours to obtain Zn-modified graphene; S2: The polyether polyol CHE-828D, epoxy resin and Zn-modified graphene are uniformly mixed and subjected to high-pressure homogenization treatment (the pressure of the high-pressure homogenization treatment is 800 Bar and the time of the high-pressure homogenization treatment is 10 min), and then isopentane, bismuth isooctanoate and water are added, and ultrasonic stirring is performed in a constant temperature water bath at 25°C for 30 min to form material A; S3: Toluene diisocyanate and terephthalic acid were mixed, and ultrasonically stirred in a constant temperature water bath at 25°C for 30 minutes to form material B; S4: Pour material B into material A rapidly, stir at high speed for 10 seconds, then quickly pour into a foaming machine, vacuum degassing, open the mold after 5 minutes, take out and mature at room temperature for 60 hours to obtain a low VOC automotive interior material.

[0023] Comparative Example 1 This comparative example provides a low VOC automotive interior material, comprising the following raw materials in parts by weight: 90 parts of polyether polyol CHE-828D, 110 parts of toluene diisocyanate, 12 parts of epoxy resin, 5 parts of terephthalic acid, 5 parts of water, 1 part of isopentane, and 0.3 parts of bismuth isooctanoate; The preparation method is: S1: Polyether polyol CHE-828D, epoxy resin, isopentane, bismuth isooctanoate and water were ultrasonically stirred in a constant temperature water bath at 25°C for 30 min to form material A; S2: Toluene diisocyanate and terephthalic acid were mixed, and ultrasonically stirred in a constant temperature water bath at 25°C for 30 minutes to form material B; S3: Pour material B into material A rapidly, stir at high speed for 10 seconds, then quickly pour into a foaming machine, vacuum degas, open the mold after 5 minutes, take out and mature at room temperature for 60 hours to obtain a low VOC automotive interior material.

[0024] Performance Test: The low VOC automotive interior materials obtained in Examples 1 to 4 and Comparative Example 1 were respectively taken as samples, and the release of volatile organic compounds (formaldehyde, acetaldehyde, benzene, toluene, ethylbenzene, xylene, styrene, and acrolein) of the samples was tested according to ISO 12219-2:2012. The test results are shown in Table 1.

[0025] Table 1

[0026] Note: ND means not detected or less than the detection limit of the method From the results in Table 1, it can be seen that the concentration of VOC emitted by the automotive interior materials in Examples 1 to 4 is significantly lower than that of the automotive interior materials in Comparative Example 1. This shows that the low-VOC automotive interior material provided by the present invention can effectively reduce the volatilization of VOC molecules by using epoxy resin, terephthalic acid and Zn-modified graphene as additives, is safer and more environmentally friendly, and has broad market prospects.

[0027] The low VOC automotive interior materials obtained in Examples 1 to 4 and Comparative Example 1 were respectively taken as samples, and their mechanical properties were tested according to GB / T 8813-2008, GB / T 6344-2008, and GB / T 6670-2008. The results are shown in Table 2.

[0028] Table 2

[0029] From the results in Table 2, it can be seen that the automotive interior materials in Examples 1 to 4 show significantly better compressive strength and tensile strength than those in Comparative Example 1, and have excellent elongation and resilience, which indicates that the introduction of Zn-modified graphene greatly improves the mechanical properties of the product.

Claims

1. A low VOC automotive interior material, characterized by: The invention comprises the following raw materials in parts by weight: 80-90 parts of polyether polyol, 100-110 parts of toluene diisocyanate, 10-15 parts of epoxy resin, 5-8 parts of terephthalic acid, 0.5-1 part of Zn-modified graphene, 3-5 parts of water, 1-3 parts of foaming agent, and 0.1-0.5 parts of bismuth isooctanoate.

2. The low VOC automotive interior material according to claim 1, characterized in that: The preparation method of Zn-modified graphene comprises: Mixing graphene and acetic acid, heating at 60-80°C for 3-4 hours for acidification, filtering, washing, and drying to obtain acidified graphene; Zinc acetate is dissolved in ethylene glycol to form an impregnation solution, and then the acidified graphene is dispersed in the impregnation solution, and placed in a constant temperature water bath at 60-80° C. and heated and stirred for 6-8 hours to obtain Zn-modified graphene.

3. The low VOC automotive interior material according to claim 2, characterized in that: The addition ratio of graphene to acetic acid is 0.1~0.5g:50~60mL.

4. The low VOC automotive interior material according to claim 2, characterized in that: The addition ratio of acidified graphene, zinc acetate and ethylene glycol is 0.1~0.2g:0.01mol:30~50mL.

5. The low VOC automotive interior material according to claim 1, characterized in that: The polyether polyol is at least one of CHE-828D, CHE-330N and TEP3600.

6. The low VOC automotive interior material according to claim 1, characterized in that: The foaming agent is at least one of n-pentane, isopentane, cyclopentane, hexane, isohexane and cyclohexane.

7. The process for preparing the low VOC automotive interior material according to any one of claims 1 to 6, characterized in that: The steps include: S1: Mix polyether polyol, epoxy resin and Zn-modified graphene evenly, perform high-pressure homogenization treatment, add foaming agent, bismuth isooctanoate and water, and perform ultrasonic stirring in a constant temperature water bath to form material A; S2: Mix toluene diisocyanate and terephthalic acid, and stir them ultrasonically in a constant temperature water bath to form material B; S3: Pour material B into material A quickly, stir at high speed for 8-10 seconds, then quickly pour into the foaming machine, vacuum degassing, open the mold after 4-5 minutes, take out and mature at room temperature for a period of time to obtain low VOC automotive interior material.

8. The process for preparing the low VOC automotive interior material according to claim 7, characterized in that: The pressure of high-pressure homogenization treatment is 500~1000Bar, and the time of high-pressure homogenization treatment is 10~15min.

9. The process for preparing the low VOC automotive interior material according to claim 7, characterized in that: The constant temperature of the water bath is 25~30℃, and the ultrasonic stirring time is 20~30min.

10. The process for preparing the low VOC automotive interior material according to claim 7, characterized in that: Mature at room temperature for 60~72h.

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