A kind of highly flame-retardant foam material for automobile and preparation method thereof

Abstract

The invention discloses a kind of high flame retardant foam material for automobile and preparation method thereof, belong to the technical field of high molecular polymer foam material. The high flame retardant foam material for automobile includes the following raw materials by weight: 100-110 parts of polyether polyols, 90-100 parts of isocyanates, 45-55 parts of foaming agents, 10-20 parts of foam stabilizers, 5-15 parts of catalysts, 5-15 parts of auxiliary agents, 1-3 parts of antioxidants, 1-3 parts of ultraviolet absorbers, 1-2 parts of chain extenders, and 0.5-1 parts of cross-linking agents. The auxiliary agent of the present invention can be grafted on the polyurethane macromolecular chain, so the auxiliary agent containing halogen-free flame retardant elements nitrogen, phosphorus, silicon and multiple long carbon chains is added into the foam material, which can not only promote the compatibility between the raw materials, but also enable the foam material to have efficient and safe flame retardant effect and excellent mechanical properties for a long time, and the combined effect of the remaining raw materials, the foam material of the present invention has excellent comprehensive performance.

Description

Technical Field

[0001] The invention belongs to the technical field of high molecular polymer foaming materials, and in particular, relates to a highly flame-retardant foaming material for automobiles and a preparation method thereof. Background Art

[0002] Polyurethane foam material is based on polyurethane, and a large number of bubbles are formed inside the polyurethane matrix through physical or chemical methods, thereby forming a cellular structure. It is precisely because of the unique cellular structure of this foam material that it has many excellent properties, such as low density, heat insulation, shock absorption, cushioning and sound absorption, so it has been widely used in the automotive industry, aerospace industry and transportation industry.

[0003] However, the current flame retardant level of polyurethane foam materials is low and cannot meet the requirements of today's new national standards, and the safety risks are relatively high. Flame retardant modification is usually achieved by adding flame retardants, which are divided into halogen flame retardants and halogen-free flame retardants. Halogen flame retardants are more harmful, so halogen-free flame retardants are mostly used at present. Halogen-free flame retardants are mainly divided into inorganic flame retardants and organic flame retardants. Inorganic flame retardants have poor flame retardant ability and usually require a large amount of filling to achieve the required flame retardant effect. Although organic flame retardants such as diethyl aluminum phosphinate and melamine cyanurate (MCA) have good flame retardant effects, they will slowly precipitate as the use time increases, resulting in a decrease in flame retardant properties. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a highly flame-retardant foam material for automobiles and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A highly flame-retardant foaming material for automobiles comprises the following raw materials in parts by weight: 100-110 parts of polyether polyol, 90-100 parts of isocyanate, 45-55 parts of foaming agent, 10-20 parts of foam stabilizer, 5-15 parts of catalyst, 5-15 parts of auxiliary agent, 1-3 parts of antioxidant, 1-3 parts of ultraviolet absorber, 1-2 parts of chain extender and 0.5-1 parts of cross-linking agent.

[0007] Furthermore, the polyether polyol is one or more of polytetramethylene glycol, polypropylene glycol, polyoxypropylene tetraol, and polytrimethylene ether glycol.

[0008] Furthermore, the isocyanate is one or more of diphenylmethane-4,4' diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and polymethylene polyphenyl polyisocyanate.

[0009] Furthermore, the foaming agent is one or more of trichlorofluoromethane, dichlorodifluoromethane, trifluoroiodomethane, 1,1,3,3-pentafluoropropane, and 1,1,1,3,3-pentafluorobutane.

[0010] Furthermore, the foam stabilizer is one or more of organic silicon foam stabilizers.

[0011] Furthermore, the catalyst is one or more of 1,5,7-triazidobicyclo (4,4,0) dec-5-ene, 1,8-diazabicycloundec-7-ene, and 1,5-diazabicyclo (4,3,0) non-5-ene.

[0012] Furthermore, the auxiliary agent is prepared by the following steps:

[0013] S1. Add 1,3-diamino-2-hydroxypropane, triethylamine and dichloromethane to a dry round-bottom flask under nitrogen protection, slowly add tetradecanoyl chloride in a constant pressure dropping funnel to the round-bottom flask under ice-water bath conditions, and continue to react for 30 minutes after the addition is complete. After the reaction is complete, desolventize and obtain intermediate 1; the amount ratio of 1,3-diamino-2-hydroxypropane, tetradecanoyl chloride, triethylamine and dichloromethane is 0.05 mol: 0.055 mol: 8.3 mL: 110 mL;

[0014] Under the condition of ice water bath, -NH2 of 1,3-diamino-2-hydroxypropane and the acyl chloride of tetradecanoyl chloride undergo amidation reaction. The reaction process is as follows:

[0015]

[0016] S2. Add intermediate 1, triethylamine and DMSO (dimethyl sulfoxide) to a dry three-necked flask under nitrogen protection, stir and dissolve, slowly add tetradecane chloride, heat to 60° C. and react for 2 h. After the reaction is completed, cool to room temperature and distill under reduced pressure to obtain intermediate 2; the amount ratio of intermediate 1, tetradecane chloride, triethylamine and DMSO is 0.03 mol: 0.032 mol: 5 mL: 120 mL;

[0017] Under the action of triethylamine, the molar ratio of intermediate 1 to tetradecyl chloride is controlled to be 1:1 and intermediate 1 is slightly excessive, and -NH2 of intermediate 1 and -Cl of tetradecyl chloride undergo nucleophilic substitution reaction. The reaction process is as follows:

[0018]

[0019] S3, replace the air in the four-necked reaction bottle with nitrogen at room temperature, add pentaerythritol phosphate and dioxane, stir to dissolve, slowly add STC (silicon tetrachloride) dropwise, the system temperature is not higher than 20°C during the dropwise addition, keep the reaction at 30°C for 6h after the dropwise addition, wait until no HCl gas is released, cool to below 20°C, filter, rinse the filter cake with dioxane, and vacuum dry to obtain intermediate 3; the amount ratio of pentaerythritol phosphate, STC and dioxane is 0.053mol:0.025mol:100mL;

[0020] Pentaerythritol phosphate and silicon tetrachloride undergo esterification reaction at 30°C. The reaction process is as follows:

[0021]

[0022] S4, replace the air in the four-necked reaction bottle with nitrogen at room temperature, add intermediate 2 and DMF (N,N-dimethylformamide), stir and dissolve, slowly add the mixed solution of intermediate 3 and DMF with a constant pressure dropping funnel, keep warm at 40°C for 6h after the addition is completed, wait until no HCl gas is released, cool down, filter, rinse the filter cake with DMF, and dry to obtain intermediate 4; the amount ratio of intermediate 2, intermediate 3 and DMF is 0.022mol:0.02mol:100mL;

[0023] Under heating conditions, intermediate 2 and intermediate 3 undergo esterification reaction, and the reaction process is as follows:

[0024]

[0025] S5. Replace the air in the four-necked reaction bottle with nitrogen at room temperature, add intermediate 4 and DMF, stir and dissolve, slowly add the mixed solution of propylene glycol and DMF with a constant pressure dropping funnel, keep warm at 50°C for 8 hours after the addition is completed, wait until no HCl gas is released, cool to room temperature, filter, rinse the filter cake with DMF, and dry to obtain the auxiliary agent. The amount ratio of intermediate 4, propylene glycol and DMF is 18.4g:2g:140mL.

[0026] Under heating conditions, intermediate 4 and propylene glycol undergo esterification reaction, and the reaction process is as follows:

[0027]

[0028] By concentrating the halogen-free flame retardant elements of nitrogen, phosphorus, and silicon into the additive molecules, a synergistic flame retardant effect can be produced, making the additive have excellent flame retardant effect, and it can also help improve the atomic utilization rate, be more green and environmentally friendly, and have better application prospects. The phosphorus element in the additive provides an acid source, reacts with the polymer material, and promotes the formation of carbonized products; the nitrogen element provides a gas source, which can make the system expand and foam, and also promotes the formation of the carbonized layer to form porous foam carbon; the silicon element generates an inorganic heat-insulating protective layer containing -Si-O bonds and -Si-C- bonds during combustion, which not only prevents the decomposition products generated by combustion from escaping, but also inhibits the thermal decomposition of the material, achieving the purpose of high flame retardancy and low smoke emission.

[0029] The additive contains multiple long carbon chains. The methylene long carbon chains that can freely expand and rotate increase the toughness of the foaming material. In addition, according to the principle of similar compatibility, the oil-soluble long carbon chains can also increase the compatibility of the additive with other raw materials, thereby improving the dispersion uniformity of the raw materials of the foaming material. The uniform dispersion of the raw materials can promote the uniform distribution of the pores to a certain extent, thereby reducing the thermal conductivity of the foaming material and improving the thermal insulation performance of the foaming material.

[0030] The auxiliary agent contains secondary amino groups and multiple hydroxyl groups, which can react chemically with isocyanate groups under the action of a catalyst, so that the auxiliary agent can be grafted onto the polyurethane macromolecular chain and cross-linked therewith. The auxiliary agent can be highly dispersed and stably present in the foaming material, avoiding the problem that the organic small molecule flame retardant is easily migrated or escaped from the material. Therefore, the foaming material of the present invention has efficient, durable and safe flame retardant effect and mechanical properties.

[0031] Furthermore, the antioxidant is one or more of antioxidant 168, antioxidant DLTP, antioxidant 1010, and antioxidant 1076.

[0032] Furthermore, the ultraviolet absorber is one or more of the following: light stabilizer 744, ultraviolet absorber UVP-327, and ultraviolet absorber UV-P.

[0033] Furthermore, the chain extender is one or more of 1,4-butanediol, 1,6-hexanediol and glycerol.

[0034] Furthermore, the cross-linking agent is one or more of dicumyl peroxide, di-tert-butyl peroxycumene, and 2,2-dihydroxymethylbutanol.

[0035] A method for preparing a highly flame-retardant foam material for automobiles comprises the following steps:

[0036] According to the formula ratio, polyether polyol, catalyst, auxiliary agent, antioxidant, ultraviolet absorber, chain extender and cross-linking agent are added to the reactor, stirred at 50-60°C for 30-40 minutes, and then half of the foaming agent is added and continued to be stirred for 20-25 minutes; according to the formula ratio, isocyanate and foam stabilizer are added to another reactor at 60-70°C, stirred for 20-30 minutes, and then the other half of the foaming agent is added and continued to be stirred for 15-20 minutes; the materials in the two reactors are mixed by a gun head, and injected into the foaming target cavity for foaming to obtain a foaming material.

[0037] The beneficial effects of the present invention are as follows: the additive of the present invention can be grafted onto the polyurethane macromolecular chain. Therefore, adding the additive containing halogen-free flame retardant elements such as nitrogen, phosphorus, silicon and multiple long carbon chains into the foaming material can not only promote the compatibility between the raw materials, but also enable the foaming material to have a long-term efficient and safe flame retardant effect and excellent mechanical properties. In addition, with the combined effect of the other raw materials, the foaming material of the present invention has excellent comprehensive performance. DETAILED DESCRIPTION

[0038] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Example 1

[0040] Preparation of auxiliary agent, the specific steps are as follows:

[0041] S1. Under nitrogen protection, 4.5 g of 1,3-diamino-2-hydroxypropane, 8.3 mL of triethylamine and 110 mL of dichloromethane were added to a 250 mL dry round-bottom flask. 15 mL of tetradecanoyl chloride in a constant pressure dropping funnel was slowly added to the round-bottom flask under ice-water bath conditions. After the addition was complete, the reaction was continued for 30 min. After the reaction was completed, the solvent was removed under reduced pressure to obtain intermediate 1.

[0042] S2. Under nitrogen protection, add 9 g of intermediate 1, 5 mL of triethylamine and 120 mL of DMSO to a dry 250 mL three-necked flask, stir to dissolve, slowly add 7.5 g of tetradecane chloride, heat to 60 °C and react for 2 h. After the reaction is completed, cool to room temperature and distill under reduced pressure to obtain intermediate 2.

[0043] S3, replace the air in a 250mL four-necked reaction bottle with nitrogen at room temperature, add 9.55g of pentaerythritol phosphate and 100mL of dioxane, stir to dissolve, slowly drop 2.9mL STC, the system temperature is not higher than 20°C during the dropwise addition, keep the reaction at 30°C for 6h after the dropwise addition, wait until no HCl gas is released, cool to below 20°C, filter, rinse the filter cake with dioxane, and dry in vacuo to obtain intermediate 3;

[0044] S4, replace the air in a 250mL four-necked reaction bottle with nitrogen at room temperature, add 10.9g of intermediate 2 and 115mL of DMF, stir and dissolve, slowly add 9.1g of intermediate 3 and 15mL of DMF using a constant pressure dropping funnel, keep warm at 40°C for 6h after the addition is complete, cool down, filter, rinse the filter cake with DMF, and dry to obtain intermediate 4;

[0045] S5. Replace the air in a 250mL four-necked reaction bottle with nitrogen at room temperature, add 18.4g of intermediate 4 and 130mL of DMF, stir to dissolve, slowly add 2g of propylene glycol and 10mL of DMF using a constant pressure dropping funnel, and after the addition is complete, keep the reaction at 50°C for 8h, wait until no HCl gas is released, cool to room temperature, filter, rinse the filter cake with DMF, and dry to obtain an auxiliary agent.

[0046] Example 2

[0047] The foaming material is prepared in the following specific steps:

[0048] According to the formula ratio, 110 parts of polytrimethylene ether glycol, 15 parts of 1,5-diazabicyclo (4,3,0) non-5-ene, 15 parts of the auxiliary agent prepared in Example 1, 1 part of antioxidant DLTP, 2 parts of antioxidant 1076, 1 part of light stabilizer 744, 2 parts of ultraviolet absorber UV-P, 2 parts of 1,6-hexanediol and 1 part of di-tert-butyl peroxyisopropylbenzene were added to a reactor, stirred at 50°C for 39 minutes, and then 27.5 parts of trifluoroiodomethane were added and stirred for 24 minutes; according to the formula ratio, 100 parts of toluene diisocyanate and 20 parts of silicone foam stabilizer AK-8805 were added to another reactor at 60°C, stirred for 28 minutes, and then 27.5 parts of trifluoroiodomethane were added and stirred for 18 minutes; the materials in the two reactors were mixed by a gun tip and injected into the foaming target cavity for foaming to obtain a polyurethane foam material.

[0049] Example 3

[0050] The foaming material is prepared in the following specific steps:

[0051] According to the formula ratio, 100 parts of polyoxypropylene tetraol, 5 parts of 1,8-diazabicycloundec-7-ene, 5 parts of the auxiliary agent prepared in Example 1, 1 part of antioxidant 1076, 1 part of ultraviolet absorber UV-P, 1 part of glycerol and 0.5 part of diisopropylbenzene peroxide were added to a reactor, stirred at 55° C. for 30 minutes, and then 22.5 parts of 1,1,3,3-pentafluoropropane were added and stirred for 20 minutes; according to the formula ratio, 90 parts of diphenylmethane-4,4' diisocyanate and 10 parts of silicone foam stabilizer AK-8805 were added to another reactor at 65° C., stirred for 20 minutes, and then 22.5 parts of 1,1,3,3-pentafluoropropane were added and stirred for 15 minutes; the materials in the two reactors were mixed by a gun tip, and injected into a foaming target cavity for foaming to obtain a polyurethane foam material.

[0052] Example 4

[0053] The foaming material is prepared in the following specific steps:

[0054] According to the formula ratio, 108 parts of polytetrahydrofuran diol, 10 parts of 1,5,7-triazidobicyclo (4,4,0) dec-5-ene, 13 parts of the auxiliary agent prepared in Example 1, 1 part of antioxidant 168, 1 part of antioxidant 1010, 1 part of light stabilizer 744, 1 part of ultraviolet absorber UVP-327, 1.5 parts of 1,4-butanediol and 0.6 parts of 2,2-dihydroxymethylbutanol were added to a reaction kettle, stirred at 60° C. for 40 minutes, and then 25 96 parts of polymethylene polyphenyl polyisocyanate and 15 parts of silicone foam stabilizer AK-8805 were added into another reaction kettle according to the formula ratio and stirred at 70°C for 30 minutes, and then 25 parts of 1,1,1,3,3-pentafluorobutane were added and stirred for 20 minutes; the materials in the two reaction kettles were mixed by a gun tip and injected into the foaming target cavity for foaming to obtain a polyurethane foam material.

[0055] Comparative Example 1

[0056] Preparation of auxiliary agent, the specific steps are as follows:

[0057] The remaining steps remain unchanged, and only step S5 of Example 1 is removed to prepare the auxiliary agent.

[0058] Comparative Example 2

[0059] The foaming material is prepared in the following specific steps:

[0060] The remaining steps remain unchanged, only the auxiliary agent in Example 4 is removed to prepare the foaming material.

[0061] Comparative Example 3

[0062] The foaming material is prepared in the following specific steps:

[0063] The remaining steps remained unchanged, only the auxiliary agent in Example 4 was replaced by the auxiliary agent in Comparative Example 1 to prepare a foaming material.

[0064] Comparative Example 4

[0065] The foaming material was prepared by keeping the other steps unchanged, except that the auxiliary agent in Example 4 was replaced by 8 parts of ammonium polyphosphate and 5 parts of melamine cyanurate to obtain the foaming material.

[0066] Performance Testing

[0067] The foamed materials prepared in Examples 2-4 and Comparative Examples 2-4 were made into corresponding samples according to different standards for performance testing. The test results are shown in the following table:

[0068] Test items Tear strength N / m Elongation % Limiting oxygen index % Thermal conductivity mW / (mk) standard GB / T10808-2006 GB / T6344-2008 ISO4589 GB / T10295-2008 Example 2 442 105 40.7 18.2 Example 3 439 102 40.2 18.5 Example 4 446 107 41.1 18.0 Comparative Example 2 415 91 20.1 20.6 Comparative Example 3 431 99 39.8 19.1 Comparative Example 4 420 94 35.7 20.3

[0069] It can be seen from the data in the above table that the foaming materials prepared in Examples 2-4 of the present invention have excellent flame retardant properties and can be used as highly flame retardant foaming materials for automobiles.

[0070] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0071] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A highly flame-retardant foam material for automobiles, characterized in that: The invention comprises the following raw materials in parts by weight: 100-110 parts of polyether polyol, 90-100 parts of isocyanate, 45-55 parts of foaming agent, 10-20 parts of foam stabilizer, 5-15 parts of catalyst, 5-15 parts of auxiliary agent, 1-3 parts of antioxidant, 1-3 parts of ultraviolet absorber, 1-2 parts of chain extender and 0.5-1 parts of cross-linking agent; Wherein, the auxiliary agent is prepared by the following steps: S1. 1,3-diamino-2-hydroxypropane, triethylamine and dichloromethane were added to a flask under nitrogen protection, tetradecanoyl chloride was added to the flask under ice water bath, reacted for 30 minutes, and desolventized under reduced pressure to obtain intermediate 1. The reaction process is as follows: S2. Add intermediate 1, triethylamine and DMSO to a flask under nitrogen protection, stir, add tetradecane chloride, react at 60° C. for 2 h, and distill under reduced pressure to obtain intermediate 2. The reaction process is as follows: S3, replace the air in the bottle with nitrogen, add pentaerythritol phosphate and dioxane, stir, add silicon tetrachloride dropwise, react at 30°C for 6h, cool, filter, rinse the filter cake, and dry to obtain intermediate 3. The reaction process is as follows: S4, replace the air in the bottle with nitrogen, add intermediate 2 and DMF, stir, add intermediate 3 and DMF, react at 40°C for 6h, cool, filter, rinse the filter cake, dry to obtain intermediate 4, the reaction process is as follows: S5. Replace the air in the bottle with nitrogen, add intermediate 4 and DMF, stir, add propylene glycol and DMF, react at 50°C for 8h, cool, filter, wash the filter cake, dry, and obtain the auxiliary agent. The reaction process is as follows:

2. A highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The usage ratio of 1,3-diamino-2-hydroxypropane, tetradecanoyl chloride, triethylamine and dichloromethane in step S1 is 0.05mol:0.055mol:8.3mL:110mL; the usage ratio of intermediate 1, chlorotetradecane, triethylamine and DMSO in step S2 is 0.03mol:0.032mol:5mL:120mL; the usage ratio of pentaerythritol phosphate, silicon tetrachloride and dioxane in step S3 is 0.053mol:0.025mol:100mL; the usage ratio of intermediate 2, intermediate 3 and DMF in step S4 is 0.022mol:0.02mol:100mL; the usage ratio of intermediate 4, propylene glycol and DMF in step S5 is 18.4g:2g:140mL.

3. The highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The polyether polyol is one or more of polytetramethylene glycol, polypropylene glycol, polyoxypropylene tetraol and polytrimethylene ether glycol.

4. The highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The isocyanate is one or more of diphenylmethane-4,4' diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and polymethylene polyphenyl polyisocyanate.

5. The highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The foaming agent is one or more of trichlorofluoromethane, dichlorodifluoromethane, trifluoroiodomethane, 1,1,3,3-pentafluoropropane and 1,1,1,3,3-pentafluorobutane.

6. The highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The foam stabilizer is one or more of organic silicon foam stabilizers.

7. The highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The catalyst is one or more of 1,5,7-triazidobicyclo (4,4,0) dec-5-ene, 1,8-diazabicycloundec-7-ene, and 1,5-diazabicyclo (4,3,0) non-5-ene.

8. The highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The antioxidant is one or more of antioxidant 168, antioxidant DLTP, antioxidant 1010, and antioxidant 1076; the ultraviolet absorber is one or more of light stabilizer 744, ultraviolet absorber UVP-327, and ultraviolet absorber UV-P.

9. The highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The chain extender is one or more of 1,4-butanediol, 1,6-hexanediol and glycerol; the crosslinking agent is one or more of dicumyl peroxide, di-tert-butyl peroxycumene and 2,2-dihydroxymethylbutanol.

10. The method for preparing a highly flame-retardant foam material for automobiles according to claim 1, characterized in that: The following steps are involved: Add polyether polyol, catalyst, additive, antioxidant, ultraviolet absorber, chain extender and cross-linking agent into a reactor according to the formula ratio, stir, then add half of the foaming agent and continue to stir; add isocyanate and foam stabilizer into another reactor according to the formula ratio, stir, then add the other half of the foaming agent and continue to stir; mix the materials in the two reactors through a gun head, and inject them into a foaming target cavity for foaming to obtain a foaming material.

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