Structural protection polyurethane foam applied to automobile glass transportation and preparation method of structural protection polyurethane foam

Abstract

The invention provides structural protection polyurethane foam applied to automobile glass transportation and a preparation method thereof. The structural protection polyurethane foam material is prepared from polyol, isocyanate, a chain extender, a catalyst, water, a foam stabilizer and a flame retardant through step-by-step chemical reaction. The material is a novel transportation packaging material, has high structural strength and bending resistance, is easy to install, and can greatly save transportation space, increase transportation quantity, reduce transportation cost and reduce carbon emission for transportation of traditional automobile glass.

Description

Technical Field

[0001] The invention belongs to the field of automobile parts transportation, and in particular relates to structural protective polyurethane foam used for automobile glass transportation and a preparation method thereof. Background Art

[0002] With the development of the automobile industry, the body structure of automobiles has also undergone significant changes, especially in new energy vehicles. Among them, the most obvious change is the sunroof. More than 80% of the entire roof is basically a glass sunroof. Of course, this has improved the overall grade of the vehicle to a certain extent. But as we all know, glass products are prone to shattering during transportation. In order to reduce the breakage rate of glass products, adequate protection must be done every time they are transported. Due to excessive packaging, the number of single shipments will be greatly reduced, which will require more transportation costs.

[0003] In order to solve this problem, the present invention not only needs to develop a structural protective polyurethane foam material, but also needs to make the material durable. Simplify the processing steps of parts, reduce costs, and change the current situation of high transportation costs of traditional automotive glass. This material is not only suitable for protective materials during the transportation of automotive glass, but can also be used as a new material in the fields of automotive shock absorption, anti-collision and other parts.

[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 polyurethane foam for protecting the transportation structure of automobile glass and a preparation method thereof.

[0006] The present invention provides a polyurethane foam material for protecting the transportation structure of automobile glass, comprising the following substances in mass ratio:

[0007] Polyol: 100;

[0008] Chain extender: 5-20;

[0009] The mass ratio of isocyanate is: 80-120;

[0010] Catalyst: 0.1~2;

[0011] Flame retardant: 1-10;

[0012] Foam stabilizer: 0.1~3;

[0013] Deionized water: 0.1~1,

[0014] The polyol is a single polyester polyol or a mixture of a special polyether polyol and a polyester polyol. The ratio of the special polyether polyol to the polyester polyol is (1-5):(10-5).

[0015] Furthermore, the special polyether polyol can be a mixture of multiple polyether polyols. The mixture mainly contains the following two polyether polyols: polyether polyol A and polyether polyol B.

[0016] Furthermore, the polyether polyol A is a trifunctional polyether polyol obtained by block grafting EO and PO at a ratio of 5-10:1-5 using trimethylolpropane as an initiator, and accounts for 1% to 50% of the special polyether polyol.

[0017] Furthermore, the polyether polyol B is a difunctional polyether polyol, which is block-grafted with EO and PO in a ratio of 1-5:5-10 using ethylene glycol as an initiator, and accounts for 99% to 50% of the special polyether polyol.

[0018] Furthermore, the polyester polyol is a trifunctional, special modified polyester polyol based on adipic acid-diethylene glycol.

[0019] Furthermore, the isocyanate is any one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, polyether-modified diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

[0020] 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.

[0021] Furthermore, the catalyst and flame retardant both have reactive hydroxyl or amino groups.

[0022] Furthermore, the foam stabilizer is polyether-modified siloxane; the polyurethane foam material is bent 90° for 10,000 times according to the requirements of EN-344 standard, and the notch is not damaged; the surface hardness of the polyurethane foam material is ≥85° on the Shore A scale.

[0023] In addition, the invention also includes a preparation method of polyurethane foam for structural protection of automobile glass transportation: first, a polyurethane slurry is prepared by a typical two-step synthesis method:

[0024] S1: Preparation of polyurethane premix

[0025] S2: Preparation of polyurethane slurry

[0026] Among them, the stirring rate in S1 is controlled at 300-800 r / min;

[0027] The stirring rate in S2 is controlled at 1000-3000 r / min.

[0028] Then the polyurethane slurry prepared in S2 is poured into a mold for foaming to prepare a structural protective polyurethane foam, and the mold temperature is controlled between 60°C and 70°C.

[0029] After forming in the mold, a structural protective polyurethane foam material is prepared.

[0030] The present invention has the following advantages:

[0031] 1. The present invention uses a two-step method to synthesize polyurethane slurry for foaming. First, various polyether polyols, polyester polyols, catalysts, silicone oils, flame retardants and other additives are premixed by physical stirring to obtain corresponding premixed products, so that the raw materials of each component are dispersed more evenly in the reaction system. Then, isocyanate is added to the reaction system, and the mixed raw material slurry is quickly injected into the mold under high-speed stirring to complete product production.

[0032] 2. Compared with traditional sponge foaming, this product adopts mold molding, and achieves efficient output by controlling the mold temperature and holding time. The molding process of this product is simple and easy to operate. It can be molded in one time for complex structural shapes, ensuring the dimensional stability of the product while achieving product consistency.

[0033] 3. The present invention selects a mixture of polyester polyol and polyether polyol as the main polyol and adds a chain extender and a cross-linking agent to ensure that the product has high structural strength, bending resistance and hardness.

[0034] 4. The polyurethane foam material used in the transportation of automobile glass structures is not only suitable for protective materials in the transportation of automobile glass, but can also be used as a new material in the fields of automobile shock absorption, anti-collision and other parts. DETAILED DESCRIPTION

[0035] 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 describe the polyurethane foam for structural protection of automobile glass transportation and the preparation method of the present invention.

[0036] Embodiment 1

[0037] In this embodiment, the polyurethane foam material used for the structural protection of automobile glass transportation includes: 1000g polyester polyol (PE, Stepan), 1200g polyether modified diphenylmethane diisocyanate (MDI, BASF), 100g 1,4-butanediol (BDO, domestic), 80g reactive phosphate flame retardant (Z, Klein), 5g reactive catalyst (AN, Evonik), 15g foam stabilizer (B, Evonik), and 2g deionized water (homemade).

[0038] The preparation method of the polyurethane foam material used for the transportation structure protection of automobile glass comprises the following steps:

[0039] Step S1, adding 1000g of polyester polyol and 100g 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.

[0040] Step S2, lowering the temperature to 20°C-25°C, adding 80g of flame retardant, 15g of foam stabilizer, 5g of catalyst, and 2g of deionized water to the premix components in sequence, and continuing to stir for 60s, then quickly adding 1200g of polyether-modified diphenylmethane diisocyanate to the premix, increasing the stirring rate to 2000r / min, stirring for 3s, and preparing a polyurethane slurry.

[0041] Then pour the polyurethane slurry prepared above into a mold for foaming, control the mold temperature at 65°C, prepare a structural protective polyurethane foam, keep the polyurethane foam under pressure for 15 minutes, take out the product from the mold, and trim off the flash to obtain a finished structural protective polyurethane foam material.

[0042] The present invention uses a two-step method to synthesize polyurethane slurry for foaming. Compared with the traditional one-step method, the present invention makes the raw materials of each component dispersed more evenly in the reaction system. Then add isocyanate to the reaction system, and under the condition of high-speed stirring, quickly inject the mixed raw material slurry into the mold to complete the product production. However, the defect of the two-step method is that the conventional two-step operation has an additional process compared to the one-step method, the process is relatively complicated, the control of the process is more stringent, the efficiency is low, and the production cost is high. In order to solve this problem: the current general method is to use an efficient catalyst to achieve part of the operation. However, in the formula system of the structural protective material, the viscosity of each raw material is relatively different. The one-step method is used for the reaction, and the raw materials are not easy to mix evenly. Therefore, we need to premix the raw materials of each component evenly before performing the synthesis reaction to achieve a product with consistent performance.

[0043] Since the material of the present invention is used to transport glass, according to the characteristics of glass, the carrier that fixes it for transportation not only needs to have sufficient structural strength, but also must have sufficient bending resistance to ensure that the glass has a certain buffering and energy absorption effect during transportation, prevent the glass from breaking, and at the same time increase the function of reusing the material.

[0044] By selecting a mixture of polyester polyols and polyether polyols as the main polyol, and adding chain extenders and crosslinkers, the product is guaranteed to have high structural strength, bending resistance and hardness. Specifically, polyester polyols are obtained by polycondensation of dicarboxylic acids and diols, etc., and contain more polar groups such as ester groups and amino groups in the molecule, with strong cohesive strength and adhesion, and have high strength, wear resistance, oil resistance, aging resistance, etc. Polyether polyols are obtained by polyaddition reaction of initiators with ethylene oxide, propylene oxide, etc. in the presence of catalysts, and contain more non-polar groups such as ether bonds and hydroxyls in the molecule. The molecular chain is soft, with a lower glass transition temperature, higher ductility, water resistance, low temperature resistance, etc.

[0045] Therefore, the mixture of polyester polyols and polyether polyols can take into account the advantages of both and improve the comprehensive performance of the product.

[0046] The difficulty of this invention is that the material needs to have a higher hardness, but at the same time it also needs to have good toughness. It is well known that in general, the hardness and toughness of a material are contradictory. The harder the hardness, the worse the toughness, especially during the bending process, it is easy to break. In order to solve this difficulty, we chose a polyurethane system to synthesize this polymer material. Because this material has a lot of room for adjustment in terms of raw material selection and formula design. In terms of the main raw materials, a mixture of polyester polyols and polyether polyols is selected to adjust the toughness and hardness of the product, and it is also necessary to combine polyether modified MDI to make the final adjustment. Finally, through experimental verification and optimization of raw material types and ratios, the problems of hardness and toughness are solved at the same time.

[0047] Embodiment 2

[0048] 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 polyester polyol and special polyether polyol (PPG, self-prepared), wherein polyester polyol: special polyether polyol = 9:1; special polyether polyol is polyether polyol A: polyether polyol B = 4:1, and the addition ratio of flame retardant to polyol is 5:100. In step S1, the stirring rate is 400r / min; in step S2, the stirring rate is 2000r / min.

[0049] Embodiment 3

[0050] 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 special polyether polyol is polyether polyol A:polyether polyol B=2:1.

[0051] Embodiment 4

[0052] The same descriptions of the parts of this embodiment and the second embodiment are omitted. The difference between this embodiment and the second embodiment is that polyester polyol: special polyether polyol = 7:1, and the special polyether polyol is polyether polyol A: polyether polyol B = 2:1.

[0053] Comparative Example 1

[0054] In this comparative example, the polyurethane foam material includes: 1000g polyester polyol (PE, Stepan), 550g toluene diisocyanate (TDI, BASF), 100g 1,4-butanediol (BDO, domestic), 80g flame retardant (phosphate flame retardant, domestic), 5g catalyst (triethylamine, domestic), 15g foam stabilizer (B, Evonik), and 2g deionized water (homemade).

[0055] Comparative Example 2

[0056] 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 polyol is a mixture of polyester polyol and special polyether polyol (PPG, self-mixed), wherein polyester polyol: special polyether polyol = 7:1, special polyether polyol is polyether polyol A: polyether polyol B = 2:1, and the addition ratio of flame retardant to polyether polyol is 2:100.

[0057] 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. The performance test method is as follows:

[0058] Tensile properties: According to GB / T 528-1998 standard, the tensile strength and elongation at break properties were tested using an electronic universal testing machine.

[0059] Bending strength: According to the EN-344 standard, use a notch knife to make three small holes. After bending at a 90° bending angle and a specific speed for a certain number of times, use a magnifying glass to check the degree of stretch resistance.

[0060] Surface hardness: Use "HANDPI" LX-A surface hardness tester to test the surface hardness of foam materials.

[0061] Table 1.

[0062]

[0063]

[0064] In Table 1, compared with Examples 2 to 4, Example 1 is a single polyester polyol, while the polyols in Examples 2 to 4 are a mixture of polyester polyol and special polyether polyol. By comparison, the addition of special polyether polyol can improve the bending resistance of the sponge. At the same time, under the premise of meeting the surface hardness of the sponge, the tensile elongation of the foam can also be appropriately improved.

[0065] In Example 2 and Example 4, in the process of preparing the polyurethane foam material, the bending resistance of the product is improved mainly by adjusting the ratio of polyester polyol to polyether polyol, and adjusting the ratio of the two polyether components in the special polyether polyol. For example, in Example 2 to Example 4, the proportion of polyester decreases, the proportion of special polyether increases, specifically the proportion of polyether polyol B increases, the bending resistance of the product is improved, but the hardness of the product is reduced at the same time.

[0066] In Table 1, the examples are compared with the comparative examples, using different isocyanates as the synthetic injection materials, among which toluene diisocyanate is used, the hardness and tensile strength of the product will be significantly reduced, but the elongation of the product will be improved, and the bending resistance will also be significantly improved. This shows that toluene diisocyanate is more resilient than polyether-modified diphenylmethane diisocyanate, so the elongation at break and the bending resistance are improved.

[0067] 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. Applied to the structural protective polyurethane foam material for automobile glass transportation, characterized in that: Includes the following substances by mass ratio: Polyol: 100; Chain extender: 5-20; The mass ratio of isocyanate is: 80-120; Catalyst: 0.1~2; Flame retardant: 1-10; Foam stabilizer: 0.1~3; Deionized water: 0.1~1; The polyol is a single polyester polyol or a mixture of a special polyether polyol and a polyester polyol. The ratio of the special polyether polyol to the polyester polyol is (1-5):(10-5).

2. The polyurethane foam material for protecting automobile glass transportation structure according to claim 1, characterized in that: The special polyether polyol may be a mixture of multiple polyether polyols.

3. The polyurethane foam material for protecting automobile glass transportation structure according to claim 2, characterized in that: The various polyether polyols include: polyether polyol A is trifunctional, uses trimethylolpropane as an initiator, and adopts EO and PO in a ratio of 5-10:1-5 for block grafting, and the proportion of polyether polyol A in the special polyether polyol is 1%-50%.

4. The polyurethane foam material for protecting automobile glass transportation structure according to claim 2, characterized in that: The various polyether polyols include: polyether polyol B is a difunctional polyether polyol that uses ethylene glycol as an initiator and is block-grafted with EO and PO in a ratio of 1-5:5-10, and accounts for 99% to 50% of the special polyether polyol.

5. The polyurethane foam material for protecting automobile glass transportation structure according to claim 1, characterized in that: The polyester polyol is a trifunctional special modified polyester polyol based on adipic acid-diethylene glycol.

6. The polyurethane foam material for protecting automobile glass transportation structure according to claim 1, characterized in that: The isocyanate is any one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, polyether-modified diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

7. The polyurethane foam material for protecting automobile glass transportation structure 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.

8. The polyurethane foam material for protecting automobile glass transportation structure according to claim 1, characterized in that: The catalyst and flame retardant both have reactive hydroxyl or amino groups.

9. The polyurethane foam material for protecting automobile glass transportation structure according to claim 1, characterized in that: The foam stabilizer is polyether-modified siloxane; the polyurethane foam material complies with the requirements of EN-344 standard, the material is bent 90° for 10,000 times without any damage to the notch; the surface hardness of the polyurethane foam material is Shore A≥85°.

10. A method for preparing any one of claims 1 to 9, 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 300~800r / min, The stirring rate in S2 is controlled at 1000-3000 r / min; Then the polyurethane slurry prepared in S2 is poured into a mold for foaming to prepare a structural protective polyurethane foam body, and the mold temperature is controlled between 60° C. and 70° C. After molding in the mold, a structural protective polyurethane foam material is prepared.

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