Fireproof flame-retardant foaming polyurethane and preparation method thereof

Abstract

The invention relates to the technical field of polyurethane foam, and discloses fireproof flame-retardant foaming polyurethane and a preparation method thereof.The foaming polyurethane comprises a component A and a component B. The component A comprises, by weight, 100 parts of polyether polyol, 25-50 parts of a flame-retardant chain extender and the like; and the component B is 62-86 parts by weight of an isocyanate compound. The flame-retardant chain extender contains a plurality of polymerization sites, so that the crosslinking density of a polyurethane molecular chain is improved, a stable crosslinking network is formed, and meanwhile, the flame-retardant chain extender contains a siloxane structural unit with structural stability, so that the foamed polyurethane has higher compression strength. The flame-retardant chain extender contains a phosphate flame-retardant group, and forms a phosphorus-silicon flame-retardant system with a siloxane structure, so that the combustion heat release rate peak value, the total heat release amount and the total smoke release amount of foam are reduced, and the flame-retardant chain extender has good fireproof and flame-retardant properties.

Description

Technical Field

[0001] The present invention relates to the technical field of polyurethane foam, and specifically relates to a fireproof and flame-retardant foamed polyurethane and a preparation method thereof. Background Art

[0002] Polyurethane foam has good properties such as heat insulation, sound insulation, waterproofing, and anti-corrosion, and is widely used in building materials, transportation, insulation layers of refrigeration equipment, etc. Polyurethane foam is usually prepared by polymerization reaction and foaming using polyols, isocyanate compounds, chain extenders, blowing agents, etc. Traditional polyurethane foam has problems such as low compressive strength and easy combustion, which limit the practical application of polyurethane foam materials. Chain extenders have a great influence on the properties of polyurethane foam. Common chain extenders include 1,4-butanediol, diethanolamine, trimethylolpropane, silicone chain extenders, phosphate polyol chain extenders, etc.

[0003] Adding flame retardants such as phosphorus-based, nitrogen-based, and silicon-based to polyurethane foam can improve its flame retardant properties. Chinese Patent CN113817170B discloses a phosphorus-nitrogen-silicon intumescent flame retardant and its preparation method and application in rigid polyurethane foam. Reacting isocyanate alkylalkoxysilane with tris(2-hydroxyethyl) isocyanurate and phosphorus-containing dichloride, the obtained macromolecular phosphorus-nitrogen-silicon flame retardant can improve the heat resistance, flame retardancy, corrosion resistance and other properties of polyurethane foam, but this phosphorus-nitrogen-silicon flame retardant does not improve the mechanical properties such as the compressive strength of polyurethane foam. Summary of the Invention

[0004] (I) Technical Problems to be Solved: Aiming at the deficiencies of the prior art, the present invention provides a fireproof and flame-retardant foamed polyurethane and a preparation method thereof, which solve the problems of poor flame retardant performance and low mechanical strength of polyurethane foam.

[0005] (II) Technical Solution: A fireproof and flame-retardant foamed polyurethane and a preparation method thereof. The fireproof and flame-retardant foamed polyurethane includes component A and component B; Component A is: 100 parts by weight of polyether polyol, 0.6 - 0.8 parts by weight of organic amine catalyst, 0.4 - 0.7 parts by weight of organotin catalyst, 2.8 - 3.6 parts by weight of deionized water, 1.8 - 2.5 parts by weight of foam stabilizer, 25 - 50 parts by weight of flame retardant chain extender; Component B is 62 - 86 parts by weight of isocyanate compound.

[0006] Preparation method of fireproof and flame-retardant foamed polyurethane: Polyether polyol, organic amine catalyst, organic tin catalyst, deionized water, foam stabilizer, and flame-retardant chain extender are stirred and mixed to obtain component A; then it is stirred and mixed with component B isocyanate compound for 8 - 12 s, quickly poured into a mold, foamed at 20 - 30 °C for 10 - 20 min, and then cured at 60 - 80 °C for 12 - 18 h to obtain fireproof and flame-retardant foamed polyurethane.

[0007] Furthermore, the polyether polyol is polytetrahydrofuran ether diol or polyether polyol N220.

[0008] Furthermore, the organic amine catalyst is triethylenediamine.

[0009] Furthermore, the foam stabilizer is an organosilicon foam stabilizer.

[0010] Furthermore, the organic tin catalyst is dibutyltin dilaurate or stannous octoate.

[0011] Furthermore, the isocyanate compound is any one or combination of isophorone diisocyanate, toluene - 2,4 - diisocyanate, diphenylmethane - 4,4'-diisocyanate, polyphenyl polymethylene polyisocyanate.

[0012] Furthermore, the preparation method of the flame-retardant chain extender includes: adding a solvent, 1,3 - bis(3 - glycidyloxypropyl)tetramethyldisiloxane with a molar ratio of 1:(2.2 - 2.6), and diethyl 4 - aminophenyl phosphate into a reaction vessel, stirring and reacting at 40 - 55 °C for 7 - 10 h, rotary evaporation, and subjecting the product to silica gel column chromatography separation, and the eluent is a mixed solution of dichloromethane and methanol to obtain the flame-retardant chain extender. The reaction formula is: 。

[0013] Furthermore, the solvent is tetrahydrofuran or isopropanol.

[0014] (III) Beneficial technical effects: In the present invention, 1,3 - bis(3 - glycidyloxypropyl)tetramethyldisiloxane and diethyl 4 - aminophenyl phosphate are reacted to obtain a flame-retardant chain extender containing multiple hydroxyl and imino polymerization sites, and then crosslinking polymerization reaction and foaming occur with the isocyanate compound and polyether polyol to obtain fireproof and flame-retardant foamed polyurethane. The flame-retardant chain extender contains multiple polymerization sites, which improves the crosslinking density of the polyurethane molecular chain, forms a stable crosslinking network, is beneficial to improving the mechanical strength of the polyurethane foam. At the same time, the flame-retardant chain extender contains a structurally stable siloxane structural unit, which can be introduced into the polyurethane molecular chain to further improve the mechanical properties of the polyurethane foam and has a higher compressive strength.

[0015] The flame retardant chain extender of the present invention contains a phosphate flame retardant group, which forms a phosphorus-silicon flame retardant system with the silicone structure. When the foam burns, the phosphate group pyrolyzes to generate phosphoric acid substances, promoting the dehydration and carbonization of the foam. The silicone structure pyrolyzes to form inorganic silicon oxide substances, which combine with the carbon layer to form a strong and stable carbon-silicon layer, which can isolate oxygen and inhibit the escape of smoke, etc., thereby reducing the peak value of the heat release rate, the total heat release, and the total smoke release of the foam, and having good fire and flame retardant properties. Detailed implementation mode

[0016] To better illustrate the purpose, technical solution and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0017] The fire and flame retardant foamed polyurethane provided by the present invention includes component A and component B; Component A is: 100 parts by weight of polyether polyol, 0.6-0.8 parts by weight of organic amine catalyst, 0.4-0.7 parts by weight of organotin catalyst, 2.8-3.6 parts by weight of deionized water, 1.8-2.5 parts by weight of foam stabilizer, 25-50 parts by weight of flame retardant chain extender; Component B is 62-86 parts by weight of isocyanate compound.

[0018] Preparation method of fire and flame retardant foamed polyurethane: Stir and mix polyether polyol, organic amine catalyst, organotin catalyst, deionized water, foam stabilizer, and flame retardant chain extender to obtain component A; then stir and mix with component B isocyanate compound for 8-12 s, quickly pour it into a mold, foam at 20-30 °C for 10-20 min, and then cure at 60-80 °C for 12-18 h to obtain fire and flame retardant foamed polyurethane.

[0019] Furthermore, the polyether polyol is polytetrahydrofuran ether diol or polyether polyol N220.

[0020] Furthermore, the organic amine catalyst is triethylenediamine.

[0021] Furthermore, the foam stabilizer is an organosilicon foam stabilizer.

[0022] Furthermore, the organotin catalyst is dibutyltin dilaurate or stannous octoate.

[0023] Furthermore, the isocyanate compound is any one or combination of isophorone diisocyanate, toluene-2,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, polyphenyl polymethylene polyisocyanate.

[0024] Further, the preparation method of the flame retardant chain extender includes: adding a solvent, 1,3-bis(3-glycidyletheroxypropyl)tetramethyldisiloxane with a molar ratio of 1:(2.2-2.6), and diethyl 4-aminophenylphosphate into a reaction vessel, stirring and reacting at 40-55°C for 7-10 h, rotary evaporation, separating the product by silica gel column chromatography, and using a mixed solution of dichloromethane and methanol as the eluent to obtain the flame retardant chain extender. The reaction formula is: 。

[0025] Further, the solvent is tetrahydrofuran or isopropanol.

[0026] The silicone foam stabilizer model in the following specific embodiments is silicone oil 8110, purchased from Shandong Sheng Teng Chemical Co., Ltd. The palladium-carbon catalyst with 10% Pd content is purchased from Maoming Xiongda Chemical Co., Ltd.

[0027] According to the method in the journal Bioorganic & Medicinal Chemistry Letters 13 (2003) 1623-1626, the literature "Structure-activity relationship on human serum paraoxonase (PON1) using substrate analogues and inhibitors", add 160 mL of methanol, 15 g of diethyl 4-nitrophenylphosphate (structural formula is ), 0.14 g of palladium-carbon catalyst into a reaction kettle, introduce pressured hydrogen and control the pressure to 0.3 MPa, stir and react at 40°C for 24 h, filter, rotary evaporate the filtrate, separate the product by silica gel column chromatography, and use a mixed solution of ethyl acetate and petroleum ether as the eluent to obtain diethyl 4-aminophenylphosphate, the structural formula is 。

[0028] Example 1 (1) Add 200 mL of tetrahydrofuran solvent, 50 mmol of 1,3-bis(3-glycidyletheroxypropyl)tetramethyldisiloxane, and 120 mmol of diethyl 4-aminophenylphosphate into a reaction vessel, stir and react at 55°C for 7 h, rotary evaporate, separate the product by silica gel column chromatography, and use a mixed solution of dichloromethane and methanol as the eluent to obtain the flame retardant chain extender.

[0029] (2) Stir and mix 100 g of polyether polyol N220 (average molecular weight about 2000), 0.8 g of triethylenediamine, 0.4 g of dibutyltin dilaurate, 3.3 g of deionized water, 2.5 g of silicone foam stabilizer, and 25 g (29.34 mmol) of flame retardant chain extender to obtain component A.

[0030] (3) Mix 29 g of isophorone diisocyanate and 38 g of polyphenyl polymethylene polyisocyanate to obtain Component B. Stir and mix Component B with Component A for 8 s, quickly pour it into a mold, foam at 20 °C for 20 min, and then cure at 60 °C for 18 h to obtain a fireproof and flame-retardant foamed polyurethane.

[0031] Example 2 (1) Add 200 mL of tetrahydrofuran solvent, 50 mmol of 1,3-bis(3-glycidyletheroxypropyl)tetramethyldisiloxane, and 130 mmol of diethyl 4-aminophenyl phosphate to a reaction vessel, stir and react at 50 °C for 7 h, perform rotary evaporation, and separate the product by silica gel column chromatography. The eluent is a mixed solution of dichloromethane and methanol to obtain a flame retardant chain extender.

[0032] (2) Stir and mix 100 g of polyether polyol N220 (average molecular weight about 2000), 0.8 g of triethylenediamine, 0.5 g of stannous octoate, 3.6 g of deionized water, 1.8 g of silicone foam stabilizer, and 40 g of flame retardant chain extender to obtain Component A.

[0033] (3) Mix 24 g of toluene-2,4-diisocyanate and 42 g of polyphenyl polymethylene polyisocyanate to obtain Component B. Stir and mix Component B with Component A for 8 s, quickly pour it into a mold, foam at 20 °C for 20 min, and then cure at 80 °C for 12 h to obtain a fireproof and flame-retardant foamed polyurethane.

[0034] Example 3 (1) Add 150 mL of isopropanol solvent, 50 mmol of 1,3-bis(3-glycidyletheroxypropyl)tetramethyldisiloxane, and 110 mmol of diethyl 4-aminophenyl phosphate to a reaction vessel, stir and react at 40 °C for 10 h, perform rotary evaporation, and separate the product by silica gel column chromatography. The eluent is a mixed solution of dichloromethane and methanol to obtain a flame retardant chain extender.

[0035] (2) Stir and mix 100 g of polytetrahydrofuran ether diol (average molecular weight about 2000), 0.6 g of triethylenediamine, 0.7 g of dibutyltin dilaurate, 2.8 g of deionized water, 1.8 g of silicone foam stabilizer, and 50 g of flame retardant chain extender to obtain Component A.

[0036] (3) Mix 39 g of diphenylmethane-4,4'-diisocyanate and 47 g of polyphenyl polymethylene polyisocyanate to obtain Component B. Stir and mix Component B with Component A for 12 s, quickly pour it into a mold, foam at 30 °C for 10 min, and then cure at 70 °C for 18 h to obtain a fireproof and flame-retardant foamed polyurethane.

[0037] Comparative Example 1 According to the method in the literature "Synthesis of Flame Retardant Polyols and Their Application in Polyurethane Foams" in the 6th issue of the 31st volume of "Polymer Materials Science and Engineering" in June 2015, flame retardant polyols were prepared using diethylene glycol and phenylphosphonic dichloride as raw materials. The structural formula is .

[0038] (1) 100 g of polyether polyol N220 (average molecular weight about 2000), 0.8 g of triethylenediamine, 0.4 g of dibutyltin dilaurate, 3.3 g of deionized water, 2.5 g of silicone foam stabilizer, and 9.80 g (29.34 mmol) of flame retardant polyol were stirred and mixed to obtain Component A.

[0039] (2) 29 g of isophorone diisocyanate and 38 g of polyphenyl polymethylene polyisocyanate were mixed to obtain Component B, which was stirred and mixed with Component A for 8 s, quickly poured into a mold, foamed at 20 °C for 20 min, and then cured at 60 °C for 18 h to obtain fireproof and flame retardant foamed polyurethane.

[0040] Comparative Example 2 (1) 100 g of polyether polyol N220 (average molecular weight about 2000), 0.8 g of triethylenediamine, 0.4 g of dibutyltin dilaurate, 3.3 g of deionized water, 2.5 g of silicone foam stabilizer, and 8.16 g (29.34 mmol) of 1,3-bis(4-hydroxybutyl)tetramethyldisiloxane (CAS Registry Number 5931-17-9) were stirred and mixed to obtain Component A.

[0041] (2) 29 g of isophorone diisocyanate and 38 g of polyphenyl polymethylene polyisocyanate were mixed to obtain Component B, which was stirred and mixed with Component A for 8 s, quickly poured into a mold, foamed at 20 °C for 20 min, and then cured at 60 °C for 18 h to obtain fireproof and flame retardant foamed polyurethane.

[0042] Comparative Example 3 (1) 100 g of polyether polyol N220 (average molecular weight about 2000), 0.8 g of triethylenediamine, 0.4 g of dibutyltin dilaurate, 3.3 g of deionized water, 2.5 g of silicone foam stabilizer, and 3.08 g (29.34 mmol) of diethanolamine were stirred and mixed to obtain Component A.

[0043] (2) 29 g of isophorone diisocyanate and 38 g of polyphenyl polymethylene polyisocyanate were mixed to obtain Component B, which was stirred and mixed with Component A for 8 s, quickly poured into a mold, foamed at 20 °C for 20 min, and then cured at 60 °C for 18 h to obtain fireproof and flame retardant foamed polyurethane.

[0044] The compression properties of the foamed polyurethane were tested according to the standard of GB / T 8813-2020.

[0045] The combustion performance of the foamed polyurethane was tested using a cone calorimeter with a heat radiation power of 35 kW / m 2 .

[0046] Table 1 Performance test of foamed polyurethane

[0047] After testing, when preparing the foamed polyurethane in Examples 1-3, a flame retardant chain extender was added. It contains multiple hydroxyl and imino polymerization sites, and undergoes cross-linking polymerization reactions with isocyanate compounds and polyether polyols, improving the cross-linking density of the polyurethane molecular chain and forming a stable cross-linked network, which is beneficial to improving the mechanical strength of the polyurethane foam. At the same time, the flame retardant chain extender contains a siloxane structural unit with structural stability. Introduced into the polyurethane molecular chain, it can further improve the mechanical properties of the polyurethane foam, showing a higher compressive strength. And the flame retardant chain extender contains a phosphate flame retardant group, forming a phosphorus-silicon flame retardant system with the siloxane structure. When the foam burns, the phosphate group pyrolyzes to generate phosphoric acid substances, promoting the dehydration and carbonization of the foam. The siloxane structure pyrolyzes to form inorganic silicon-oxygen substances, which combine with the carbon layer to form a strong and stable carbon-silicon layer, which can play the effects of isolating oxygen and inhibiting the escape of smoke, etc., thereby reducing the peak value of the combustion heat release rate, the total heat release, and the total smoke release of the foam, showing good fire and flame retardant properties.

[0048] Compared with Example 1, in Comparative Example 1, a flame retardant polyol was used as the chain extender, which only contains two hydroxyl polymerization sites and can only undergo linear polymerization reactions with isocyanate compounds and polyether polyols, unable to form a cross-linked network, not conducive to improving the cross-linking density of the polyurethane molecular chain, and also does not contain a siloxane structure, resulting in a lower compressive strength of the polyurethane foam, and at the same time, the peak value of the combustion heat release rate, the total heat release, and the total smoke release are higher than those in Example 1.

[0049] In Comparative Example 2, 1,3-bis(4-hydroxybutyl)tetramethyldisiloxane was used, which only contains two hydroxyl polymerization sites and cannot undergo cross-linking polymerization reactions with isocyanate compounds and polyether polyols, and also does not contain a phosphate flame retardant group, resulting in a lower compressive strength, a larger peak value of the combustion heat release rate, the total heat release, and the total smoke release, and poor mechanical strength and flame retardant properties.

[0050] In Comparative Example 3, diethanolamine containing multiple hydroxyl and imino groups was used as the chain extender, which does not contain a phosphate group and does not contain a siloxane structure, resulting in a compressive strength lower than that in Example 1, and a larger peak value of the combustion heat release rate, the total heat release, and the total smoke release, and very poor flame retardant properties.

[0051] The applicant declares that the detailed process flow of the present invention is illustrated by the above embodiments, but the present invention is not limited to the above detailed process flow, that is, it does not mean that the present invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent substitution of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A fireproof and flame-retardant foamed polyurethane, the fireproof and flame-retardant foamed polyurethane comprising component A and component B; Component A is: 100 parts by weight of polyether polyol, 0.6 - 0.8 parts by weight of organic amine catalyst, 0.4 - 0.7 parts by weight of organotin catalyst, 2.8 - 3.6 parts by weight of deionized water, 1.8 - 2.5 parts by weight of foam stabilizer, 25 - 50 parts by weight of flame-retardant chain extender; Component B is 62 - 86 parts by weight of isocyanate compound; The preparation method of the flame retardant chain extender includes: Add a solvent, 1,3-bis(3-glycidylethoxypropyl)tetramethyldisiloxane with a molar ratio of 1:(2.2 - 2.6), and diethyl 4-aminophenyl phosphate into a reaction vessel, stir and react, then rotary evaporate, and subject the product to silica gel column chromatography separation to obtain the flame-retardant chain extender.

2. The fireproof and flame-retardant foamed polyurethane according to claim 1, wherein, The polyether polyol is polytetrahydrofuran ether diol or polyether polyol N220.

3. The fireproof and flame-retardant foamed polyurethane according to claim 1, wherein, The organic amine catalyst is triethylenediamine; the foam stabilizer is an organosilicon foam stabilizer.

4. The fireproof and flame-retardant foamed polyurethane according to claim 1, characterized in that, The organotin catalyst is dibutyltin dilaurate or stannous octanoate.

5. The fireproof and flame-retardant foamed polyurethane according to claim 1, wherein, The isocyanate compound is any one or combination of isophorone diisocyanate, toluene-2,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, polyphenyl polymethylene polyisocyanate.

6. The fireproof and flame-retardant foamed polyurethane according to claim 1, wherein, In the preparation method of the flame-retardant chain extender, the solvent is tetrahydrofuran or isopropanol.

7. The fireproof and flame-retardant foamed polyurethane according to claim 1, characterized in that, The temperature during the reaction is 40 - 55 °C, and the reaction time is 7 - 10 h.

8. A method for preparing a fireproof and flame-retardant foamed polyurethane according to any one of claims 1-7, characterized in that, The preparation method is: stir and mix the polyether polyol, organic amine catalyst, organotin catalyst, deionized water, foam stabilizer, and flame-retardant chain extender to obtain component A; then stir and mix with the isocyanate compound of component B, pour into a mold, and carry out foaming and curing to obtain the fireproof and flame-retardant foamed polyurethane.

9. The preparation method of the fireproof and flame-retardant foamed polyurethane according to claim 8, characterized in that, The foaming is carried out at 20 - 30 °C for 10 - 20 min.

10. The preparation method of the fireproof and flame-retardant foamed polyurethane according to claim 8, characterized in that, The curing is carried out at 60 - 80 °C for 12 - 18 h.

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