Preparation method of low-odor high-breathability comfortable polyurethane foam for automobile seat

Abstract

The invention provides a preparation method of low-odor high-air-permeability comfortable polyurethane foam for automobile seats, and the low-odor high-air-permeability comfortable polyurethane foam material is prepared from polyol, isocyanate, a chain extender, a catalyst, water, a foam stabilizer and a flame retardant through a step-by-step chemical reaction. Compared with a 3D mesh material, the 3D mesh material has similar air permeability and lower surface hardness and indentation hardness, is softer and more elastic in sitting feeling, is more comfortable than the 3D mesh material, not only can replace the traditional 3D mesh material, but also can reduce the material cost and carbon consumption, simplify the processing steps and realize the localization replacement of imported materials. In addition, the polyurethane foam material disclosed by the invention can meet the requirements of customers on low odor and low VOC (Volatile Organic Compounds) on the premise of ensuring the flame retardance.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile interior decoration, and in particular relates to a method for preparing low-odor, highly breathable and comfortable polyurethane foam for automobile seats. Background Art

[0002] With the development of the automobile industry, mass consumers have also put forward new requirements for the car riding experience. In order to meet the ventilation function of car seats and reduce the stuffiness of the back and buttocks of drivers and passengers during long-term driving and riding, 3Dmesh, a three-dimensional material, is used in car ventilated seats. The high air permeability of 3Dmesh is used to achieve the ventilation function of the seat. However, with the upgrading of consumption, consumers have put forward higher requirements for the comfort of car seats. The disadvantages of 3Dmesh material have also emerged. Due to the relatively hard material, it seriously affects the comfort of car seats. In order to achieve a more satisfactory riding comfort, it is necessary to add materials that can improve comfort to the seat cushion. This will not only increase the material cost and the complexity of the processing method, but most importantly, it will increase the carbon burden.

[0003] Therefore, the present invention not only needs to develop a low-odor, highly breathable polyurethane foam material, but also needs to meet the material comfort requirements. Simplify the parts processing steps, reduce costs, and achieve domestic substitution of imported materials. The material is not only suitable for car seats and backrest parts, but also can be used for medical mattresses and high-end furniture mattress materials.

[0004] To solve the above problems, we made a series of improvements. Summary of the invention

[0005] The present invention is made to solve the above problems, and aims to provide a method for preparing low-odor, highly breathable and comfortable polyurethane foam for automobile seats.

[0006] The present invention provides a low-odor, highly breathable and comfortable polyurethane foam material, comprising the following substances in mass ratio:

[0007] Polyol: 100;

[0008] Chain extender: 0.5~2;

[0009] The mass ratio of isocyanate is: 30-50;

[0010] Catalyst: 0.1~2;

[0011] Flame retardant: 1-10;

[0012] Foam stabilizer: 1-3;

[0013] Deionized water: 1~5.

[0014] The polyol is a single polyether polyol or a mixture of a polyether polyol and a polyurea polyol.

[0015] Furthermore, the polyether polyol is trifunctional, uses trimethylolpropane as an initiator, and adopts EO and PO to block-graft in a ratio of 0.5-1:5-10.

[0016] Furthermore, the solid content of the polyurea polyol is 10-50%, and the nitrogen content is 5-10%.

[0017] Furthermore, the isocyanate is any one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

[0018] Furthermore, the chain extender is a small molecule alcohol selected from any one or more combinations of ethylene glycol, 1,4-butanediol, diethylene glycol, and dipropylene glycol; the catalyst, flame retardant, and flame compounding agent all have reactive hydroxyl or amino groups; and the foam stabilizer is a polyether-modified siloxane.

[0019] Furthermore, the air permeability of the polyurethane foam material is ≥3000 mm / s, the pore size is 10-20 / cm, and the odor of the polyurethane foam material is not higher than 3.0.

[0020] Further, the surface hardness of the polyurethane foam material is within 30°.

[0021] Further, the 25% depression hardness of the polyurethane foam material is within 80N.

[0022] Preparation method of low-odor, highly breathable and comfortable polyurethane foam for car seats,

[0023] First, a polyurethane slurry was prepared using a typical two-step synthesis:

[0024] S1: Preparation of polyurethane premix,

[0025] S2: preparing polyurethane slurry,

[0026] Among them, the stirring rate in S1 is controlled at 600-800 r / min.

[0027] The stirring rate in S2 is controlled at 3000-4000 r / min;

[0028] Then, the polyurethane slurry prepared in S2 is poured into a mold for foaming to prepare a polyurethane foam with high air permeability and comfort, and then the polyurethane foam is cut to prepare a polyurethane foam material with low odor and high air permeability and comfort.

[0029] Beneficial Effects

[0030] 1. The present invention synthesizes polyurethane slurry through a two-step method for foaming. First, polyether polyol, polyurea polyol, catalyst, and isocyanate are premixed to obtain a corresponding premixed product, and then the high air permeability of the sponge is achieved by controlling the stirring speed of the second step reaction.

[0031] 2. Compared with traditional sponge foaming, catalysts or flame retardants with reactive functional groups such as alcohol hydroxyl, phenolic hydroxyl, and amino groups are used to replace traditional non-reactive additives. The reactive functional groups contained can react with isocyanate to generate part of the polyurethane foam, absorb and reduce the odor and VOC volatility of polyurethane products.

[0032] 3. The polyether polyol containing polyurea polyol selected in the present invention includes unmodified polyether polyol, polyurea dispersion, polyurea-polyurethane copolymer and a small amount of polyurethane crosslinked body, which not only makes the foam have a lower surface hardness, but also has a higher load-bearing capacity. It can also improve the flame retardant properties of the foam, replace or partially replace the flame retardant, and make the foam self-extinguishing. In addition, the shape of the polyurea polyol is spherical and the surface is multi-angular, which is helpful for the opening of the foam plastic, making the pores more open, and further improving the air permeability of the sponge.

[0033] 4. The highly air-permeable and comfortable polyurethane foam material of the present invention can not only improve the ventilation and air-permeability of the sponge, but also has a soft texture and is comfortable to sit on. It has good overall load-bearing performance and, as a ventilation and comfort material for seats, simplifies the steps of component processing and realizes the domestic substitution of imported materials. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the following examples are used to specifically illustrate the preparation method of the low-odor, highly breathable and comfortable polyurethane foam for automobile seats of the present invention.

[0035] Embodiment 1

[0036] In this embodiment, the low-odor, highly breathable and comfortable polyurethane foam material includes: 1000g polyether polyol (PPG, Shell), 350g toluene diisocyanate (TDI, BASF), 10g 1,4-butanediol (BDO, domestic), 80g reactive phosphate flame retardant (Z, Klein), 5g reactive catalyst (AN, Evonik), 15g foam stabilizer (B, Evonik), and 25g deionized water (homemade).

[0037] The preparation method of the low-odor, high-breathable and comfortable polyurethane foam material comprises the following steps:

[0038] Step S1, adding 1000g of polyether polyol and 10g of 1,4-butanediol into a reactor, heating to 50°C-60°C, performing vacuum dehydration treatment for 30min, stirring at a rate of 800r / min and continuing stirring for 2.5h to obtain a polyurethane premix.

[0039] Step S2, lower the temperature to 20°C-25°C, add 80g of flame retardant, 15g of foam stabilizer, 5g of catalyst, and 25g of deionized water to the premix components in sequence and continue stirring for 60s, then quickly add 350g of toluene diisocyanate to the premix, increase the stirring rate to 4000r / min, stir for 3s, and prepare a polyurethane slurry.

[0040] The prepared polyurethane slurry is then poured into a mold for foaming to prepare a highly breathable and comfortable polyurethane foam. The polyurethane foam is then aged for 1 to 3 days, and the sponge foam is cut by a rotary cutting process to obtain a low-odor, highly breathable and comfortable polyurethane foam material with a thickness of 2 cm.

[0041] The creativity of the present invention is reflected in the difficulty of the incompatibility between high breathability and comfort. In traditional materials, high breathability and comfort are incompatible characteristics. For example, if 3Dmesh wants to meet high breathability, the hardness of the sponge will also increase, and the comfort will decrease as the hardness increases. The reason why traditional sponges cannot achieve high breathability, flame retardancy and comfort at the same time is that if corresponding materials are added for each characteristic, first of all, the cost will be greatly increased, and secondly, the process steps will increase, making it more complicated, reducing the stability and production efficiency of the product, and finally, due to the addition of too many additional materials, the physical properties of the sponge will also deteriorate. Therefore, traditional sponge materials do not use this method to achieve both breathability and comfort at the same time.

[0042] In order to solve this problem, the present invention achieves compatibility by adding polyurea polyol. The principle is to use PUR to replace PE materials. Although traditional PUR materials can achieve comfort, the high air permeability of PE materials that want to completely replace them is a problem that cannot be solved by current traditional technologies. The present invention finds that by adding polyurea polyol, a raw material, to the formula system, the air permeability of the sponge can be improved while improving the comfort of the sponge. First, polyurea polyol is comfortable. Secondly, the reason why it has high air permeability is that in the formula system, a certain amount of polyurea polyol is added, which not only makes the foam have a lower surface hardness, but also has a higher load-bearing capacity, thereby improving the comfort of the sponge. Moreover, the flame retardant properties of the foam can be improved to replace or partially replace the flame retardant, so that the foam can be self-extinguishing. In addition, the shape of the polyurea polyol is spherical and the surface is multi-angular, which is helpful for the opening of the foam plastic, making the pores more open, and further improving the air permeability of the sponge.

[0043] Embodiment 2

[0044] The same descriptions of the parts of this embodiment and the first embodiment are omitted. The difference between this embodiment and the first embodiment is that the polyol is a mixture of polyether polyol and polyurea polyol (PHD, Covestro), wherein the ratio of polyether polyol to polyurea polyol is 9:1; the addition ratio of the flame retardant to the polyether polyol is 5:100. In step S1, the stirring rate is 400 r / min; in step S2, the stirring rate is 2000 r / min.

[0045] Embodiment 3

[0046] The same descriptions of the present embodiment and the second embodiment are omitted. The difference between the present embodiment and the second embodiment is that the ratio of polyether polyol to polyurea polyol is 7:1. The ratio of the flame retardant to the polyether polyol is 2:100.

[0047] Embodiment 4

[0048] The same descriptions of the parts of this embodiment and the second embodiment are omitted. The differences between this embodiment and the second embodiment are: polyether polyol: polyurea polyol = 7:1, the addition ratio of flame retardant and polyether polyol is 2:100, in step S1, the stirring rate is 600r / min; in step S2, the stirring rate is 1000r / min.

[0049] Comparative Example 1

[0050] In this comparative example, the polyurethane foam material includes: 1000g polyether polyol (PPG, Shell), 350g toluene diisocyanate (TDI, BASF), 10g 1,4-butanediol (BDO, domestic), 80g flame retardant (phosphate flame retardant, domestic), 5g catalyst (triethylamine, domestic), 15g foam stabilizer (B, Evonik), and 25g deionized water (homemade).

[0051] Comparative Example 2

[0052] The same descriptions are omitted for the parts of this comparative example that are the same as those of comparative example 1. The difference between this comparative example and comparative example 1 is that the polyether polyol is a mixture of polyether polyol and polyurea polyol (PHD, Covestro), wherein the ratio of polyether polyol to polyurea polyol is 7:1, and the addition ratio of flame retardant to polyether polyol is 2:100.

[0053] The samples prepared in Examples 1 to 4 and Comparative Examples 1 to 2 were subjected to performance tests, and the test results are shown in Table 1 and Table 2. The performance test method is as follows:

[0054] Tensile properties: According to DIN EN ISO 1798 standard, tensile strength and elongation at break were tested using an electronic universal testing machine.

[0055] 25% indentation hardness: According to GB / T10807 Method B standard, the 25% indentation hardness of the foam material is tested using a testing machine.

[0056] Surface hardness: Use "HANDPI" LX-F surface hardness tester to test the surface hardness of foam materials.

[0057] Air permeability: According to ISO9237:1995 standard, use air permeability meter on an area of ​​20cm 2 , air permeability test was carried out under a pressure difference of 200pa.

[0058] Pore ​​diameter: Use an electronic magnifying glass to test the pore diameter of the sponge and count the number of sponge pores within 1 cm.

[0059] Odor: According to VDA 270 standard, the odor level is evaluated by subjective test.

[0060] VOC and TVOC: VOC and TVOC content testing is performed using GC-MS mass spectrometry in accordance with GS 97014-3.

[0061] Flame retardant: tested in accordance with GS 97308 standard using a horizontal burning tester.

[0062] Table 1.

[0063]

[0064] Table 2.

[0065]

[0066]

[0067] In Table 1, compared with Examples 2 to 4, Example 1 is a single polyether polyol, while the polyether polyols in Examples 2 to 4 are a mixture of polyether polyol and polyurea polyol. In comparison, the addition of polyurea polyol can improve the opening performance of the sponge. At the same time, on the premise of meeting the surface hardness of the sponge, the foam hardness, tensile strength and bearing capacity can also be appropriately improved. On the other hand, the flame retardant performance of the polyurea polyol partially replacing the flame retardant can still reach the AO level, and the odor is reduced.

[0068] In Example 2 and Example 4, in the process of preparing the polyurethane foam material, the air permeability performance is mainly controlled by the stirring rate in the polyurethane synthesis process S2. For example, in Example 2 to Example 4, when the stirring rate of step S2 is low, the prepared air permeability is relatively large; and in Example 4, when the stirring rate is 1000r / min, the air permeability and pore size of the prepared foam material are optimal for high permeability.

[0069] In Table 1 and Table 2, compared with Comparative Example 2, the reactive catalyst and flame retardant in Example 4 are both beneficial to reducing the odor and VOC and TVOC contents of the foam material, and the elongation at break of the foam is increased compared with the control example 2, indicating that the reactive additive chemically bonds the additive body to the polyurethane molecular chain, which absorbs free volatile small molecules and becomes a part of the foam on the one hand; on the other hand, the molecular chains of the polymer compound and its derivatives are more resilient than those of direct doping due to chemical bonding, and thus the elongation at break is improved.

[0070] The above-mentioned embodiments are preferred examples of the present invention and are not intended to limit the protection scope of the present invention.

Claims

1. Low odor, highly breathable and comfortable polyurethane foam material, characterized in that: Includes the following substances by mass ratio: Polyol: 100; Chain extender: 0.5~2; The mass ratio of isocyanate is: 30-50; Catalyst: 0.1~2; Flame retardant: 1-10; Foam stabilizer: 1-3; Deionized water: 1-5; The polyol is a single polyether polyol or a mixture of a polyether polyol and a polyurea polyol.

2. The low-odor, highly breathable and comfortable polyurethane foam material according to claim 1, characterized in that: The polyether polyol is trifunctional, uses trimethylolpropane as an initiator, and adopts EO and PO to block-graft in a ratio of 0.5-1:5-10.

3. The low-odor, highly breathable and comfortable polyurethane foam material according to claim 1, characterized in that: The solid content of the polyurea polyol is 10-50%, and the nitrogen content is 5-10%.

4. The low-odor, highly breathable and comfortable polyurethane foam material according to claim 1, characterized in that: The isocyanate is any one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

5. The low-odor, highly breathable and comfortable polyurethane foam material according to claim 1, characterized in that: The chain extender is a small molecule alcohol selected from any one or more combinations of ethylene glycol, 1,4-butanediol, diethylene glycol, and dipropylene glycol; the catalyst, flame retardant, and flame compounding agent all have reactive hydroxyl or amino groups; and the foam stabilizer is a polyether-modified siloxane.

6. The low-odor, highly breathable and comfortable polyurethane foam material according to claim 1, characterized in that: The air permeability of the polyurethane foam material is ≥3000mm / s, the pore size is 10-20 / cm, and the odor of the polyurethane foam material is not higher than 3.

0.

7. The low-odor, highly breathable and comfortable polyurethane foam material according to claim 1, characterized in that: The surface hardness of the polyurethane foam material is within 30°.

8. The low-odor, highly breathable and comfortable polyurethane foam material according to claim 1, characterized in that: The 25% indentation hardness of the polyurethane foam material is within 80N.

9. A method for preparing any one of claims 1 to 8, characterized in that: First, a polyurethane slurry was prepared using a typical two-step synthesis: S1: Preparation of polyurethane premix, S2: preparing polyurethane slurry, Among them, the stirring rate in S1 is controlled at 600-800 r / min. The stirring rate in S2 is controlled at 3000-4000 r / min; Then the polyurethane slurry prepared in S2 is poured into a mold for foaming to prepare a highly breathable and comfortable polyurethane foam. The polyurethane foam body is then cut to prepare a polyurethane foam material with low odor, high air permeability and comfort.

Images