Polyurethane foam and use thereof

Abstract

The application discloses a polyurethane foaming material and application thereof, wherein the polyurethane foaming material comprises an A component and a B component, the A component is an isocyanate reactive component, and the B component is an isocyanate component. The polyurethane foaming material with high efficient filling property, which has good early flowability, stable foaming state, excellent long-term foaming flowability and fast later curing, can be obtained by selecting low-viscosity raw materials, adjusting the ratio of high-activity polyether and low-activity polyether in the raw materials and the like. Meanwhile, the material has the characteristics of high heat insulation, high open hole, excellent mechanical property and the like, is suitable for filling in a certain space, and is especially suitable for filling and fixing in gaps in a battery pack and between battery cells.

Description

Technical Field

[0001] This invention relates to the field of polyurethane foam material preparation technology, and more specifically, to a polyurethane foam material with high efficiency filling, high thermal insulation, high open-cell structure, and excellent mechanical properties, and its applications. Background Technology

[0002] Polyurethane resin possesses excellent mechanical properties, corrosion resistance, and adhesion, and is widely used in transportation, electronics, building insulation, medical devices, furniture coatings, and flooring. Potting and filling is an important application area for polyurethane resin. Before curing, polyurethane materials are liquid and flowable; after complete curing, they provide waterproofing, moisture resistance, dustproofing, insulation, sealing, corrosion resistance, temperature resistance, and shock absorption.

[0003] Energy conservation, emission reduction, and low-carbon development have become an inevitable trend. Consequently, the sales of new energy vehicles are increasing year by year, leading to a continuous increase in demand for related battery packs. Currently, the development direction of battery pack potting foam materials is: reinforcement, thermal insulation, heat transfer prevention, and lightweighting. At the same time, considering time costs, the efficiency of foam material filling is also noteworthy. Common potting materials include silicone, epoxy resin, and polyurethane. Silicone rubber has disadvantages such as poor adhesion, low bulk strength, and high density; epoxy resin has disadvantages such as poor toughness and fatigue resistance; while polyurethane materials have significant advantages in toughness and adhesion. Furthermore, polyurethane foam materials have great development potential in the battery pack potting field due to their low thermal conductivity and light weight.

[0004] CN114621721A discloses a low-density thermal insulation power battery polyurethane potting compound, which introduces hollow microspheres with hollow structures into the polyurethane potting compound matrix, effectively reducing the thermal conductivity and overall density of the polyurethane potting compound product, thereby giving it good thermal insulation effect and maintaining lightweight. However, the hollow glass microspheres used in this patent need to be surface modified, and the industrialization process is relatively complicated.

[0005] CN110392945A discloses a battery cell potting compound and its manufacturing method. It provides mechanical stability and flame retardancy to the battery cell through a potting foam composed of a flame retardant component, a compound reactive to isocyanate, water, and an isocyanate compound. However, the patent only mentions that the potting compound has sufficient fluidity before curing, but does not provide a specific description of this part.

[0006] Currently, existing technologies achieve good filling properties of polyurethane foam materials by using low-viscosity raw materials and adjusting the catalyst to obtain a long reaction time. For example, CN116199847A discloses a polyurethane foam material and its preparation method, as well as a battery pack. The polyurethane foam material described therein has sufficient fluidity before foaming and can be cured in one step after filling. CN115368527A discloses a polyurethane foam material for cylindrical battery modules, its preparation method, and its application. This polyurethane foam material possesses characteristics such as low density, low viscosity, flame retardancy, halogen-free properties, high strength, and low thermal conductivity, meeting the requirements for good thermal insulation and lightweight design between cells in cylindrical battery modules. The sufficient fluidity described in these two patents is based on the low viscosity and long reaction time of the foam material before curing. This is generally achieved by using low-viscosity raw materials and reducing the amount of catalyst. While this ensures the fluidity of the foam material to a certain extent, it also reduces the subsequent curing efficiency and cannot achieve high efficiency in the filling of the foam material.

[0007] This invention provides a polyurethane foam material with high filling capacity, characterized by low viscosity in the early stage, stable foaming state, excellent long-term foaming fluidity, and fast curing in the later stage. It also achieves high thermal insulation, high open-cell structure, and excellent mechanical properties. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a polyurethane foam material. The polyurethane foam material comprises an isocyanate reactive component A and an isocyanate component B. By adjusting the ratio of highly reactive polyethers to low-reactive polyethers in the raw materials, the incompatibility and difference in reactivity between the two components are utilized. This results in low initial viscosity, slow foaming, and a gradual increase in foam viscosity after mixing components A and B, with rapid curing in the later stages. This ensures efficient filling during potting of the foam material. Simultaneously, the material possesses high thermal insulation, high porosity, and excellent mechanical properties, making it suitable for filling spaces with a certain amount of space, particularly for filling and fixing gaps in battery packs and between battery cells.

[0009] The technical solution of this invention is as follows:

[0010] A polyurethane foam material comprising an isocyanate reactive component A and an isocyanate component B.

[0011] The isocyanate reactive component A comprises two or more polyols, including at least A1 highly reactive polyether polyol and A2 low-reactivity polyether polyol. The A1 highly reactive polyether polyol has a functionality of 2–5, preferably 3–5, and a hydroxyl value of 250–800 mgKOH / g, preferably 320–800 mgKOH / g. The A2 low-reactivity polyether polyol has a functionality of 2–8 and a hydroxyl value of 20–600 mgKOH / g.

[0012] Specifically, the A1 high-activity polyether polyol is mainly obtained by chemical reaction of water and / or polyol as initiator and EO and / or PO as polymerization monomer under the action of catalyst to obtain a class of compounds, wherein the proportion of EO in the molecular structure is 40-100 wt.%, preferably 50-100 wt., and the polymerization structure of EO and PO can be block or random structure, and the end EO capping rate is ≥30%, wherein the EO capping rate refers to the proportion of primary hydroxyl groups at the end of the polyether to all end hydroxyl groups. The initiator includes, but is not limited to, water, ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, pentanediol, hexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, diethylene glycol, neopentanediol, glycerol, trimethylolpropane, pentaerythritol, sorbitol, bisphenol A, bisphenol S, or mixtures thereof, preferably difunctional small molecule alcohols containing active hydrogen such as propylene glycol or dipropylene glycol, or trifunctional small molecule alcohols containing active hydrogen such as glycerol or trimethylolpropane; the catalyst includes, but is not limited to, basic hydroxides, basic alkoxides, antimony pentachloride, or mixtures thereof.

[0013] Preferably, the viscosity of the A1 high-activity polyether polyol at 25°C is 1–5000 mPa·s, more preferably 50–500 mPa·s;

[0014] Preferably, the content of the A1 highly reactive polyether polyol is 25-90 wt.%, more preferably 35-80 wt.%, based on the total mass of the A isocyanate reactive component.

[0015] The A2 low-activity polyether polyol mainly uses water and / or polyol as initiators and PO and / or EO as polymerization monomers. Under the action of a catalyst, it undergoes a chemical reaction to obtain a class of compounds. The EO content in the molecular structure is 0-20 wt.%, and the polymerization structure of EO and PO can be block or random, with an end-EO capping rate ≤20%. The initiators include, but are not limited to, water, ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, pentanediol, hexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, diethylene glycol, neopentyl glycol, glycerol, trimethylolpropane, pentaerythritol, sorbitol, bisphenol A, bisphenol S, or mixtures thereof. The catalysts include, but are not limited to, basic hydroxides, basic alkoxides, antimony pentachloride, or mixtures thereof.

[0016] Preferably, the viscosity of the A2 low-activity polyether polyol at 25°C is 1–50,000 mPa·s, more preferably 50–1,000 mPa·s;

[0017] Preferably, the content of A2 low-activity polyether polyol is 10-45% based on the total mass of the A isocyanate reactive component, more preferably 15-35%.

[0018] By adjusting the ratio and parameters of high-activity polyether and low-activity polyether, the incompatibility and reactivity difference between the two are utilized to ensure that after the A and B components are mixed, the viscosity is low in the early stage, the foaming is slow, the foaming viscosity increases slowly, and the curing is fast in the later stage, thus ensuring the efficient filling of the foam material during potting.

[0019] The isocyanate reactive component A preferably further comprises an A3 catalyst. Preferably, the A3 catalyst is selected from thermosensitive or temperature-sensitive, delayed-type catalysts. More preferably, the A3 catalyst includes, but is not limited to, triethylenediamine, pentamethyldialkyltriamine, tetramethylalkyldiamine, bis(dimethylaminoethyl) ether, cyclohexylmethyl tertiary amine, stannous octoate, stannous oleate, stannous laurate, dimethyl dilaurate, dibutyl dilaurate, dibutyl dithiol tin, bismuth octoate, bismuth neodecanoate, bismuth naphthenate, or combinations thereof.

[0020] The isocyanate reactive component preferably also includes an A4 flame retardant, which enables the polyurethane foam material obtained from the reaction to have a flame retardant effect. Preferably, the A4 flame retardant is a liquid flame retardant with a viscosity of 1 to 2000 mPa·s at 25°C. More preferably, the A4 liquid flame retardant has a viscosity of 60 to 500 mPa·s at 25°C. Preferred examples include, but are not limited to, tris(2-chloroethyl) phosphate, tris(2,3-dichloropropyl) phosphate, dimethyl methyl phosphate, tris(2-chloropropyl) phosphate, tricresyl phosphate, diphenyl toluene phosphate, or combinations thereof.

[0021] The isocyanate reactive component preferably further includes an A5 chain extender. Preferably, the A5 chain extender is a polyhydroxy compound with a terminal -OH group and a functionality of 1-4, preferably 2-3, including but not limited to glycerol, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, diethylene glycol, dipropylene glycol, methylpropylene glycol, 1,4-butanediol, 1,3-butanediol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-cyclohexanol, 1,6-hexanediol, diethanolamine, triethanolamine, triisopropanolamine, or combinations thereof. More preferably, the A5 chain extender is selected from ethylene glycol, propylene glycol, glycerol, trimethylolpropane, or combinations thereof.

[0022] The isocyanate reactive component A preferably also includes foam stabilizer A6. Adding foam stabilizer to the polyurethane foam material can make the reaction of components A and B more effective after mixing. Foam stabilizer includes, but is not limited to, organosilicon, polyol, silicone, sulfonated fatty alcohol, sulfonated fatty acid and other nonionic surfactants. Preferably, the foam stabilizer A6 is an organosilicon surfactant.

[0023] The isocyanate reactive component A preferably also includes a foaming agent A7. Adding a foaming agent to the polyurethane foam material can make the polyurethane porous, including but not limited to physical and chemical foaming agents. Preferably, the foaming agent A7 is water.

[0024] In some embodiments of the invention, the component comprising, by total mass of the isocyanate reactive component A, is:

[0025] The amount of A1 high-activity polyether polyol used is 25-90%, preferably 35-80%, and more preferably 40-75%;

[0026] The amount of A2 low-activity polyether polyol used is 10-45%, preferably 15-35%, and more preferably 20-30%;

[0027] The amount of A3 catalyst used is 0-1%, preferably 0.01-0.1%;

[0028] The amount of A4 flame retardant used is 0-50%, preferably 5-30%, and more preferably 10-20%;

[0029] The amount of A5 chain extender is 0-30%, preferably 5-15%, and more preferably 8-10%;

[0030] The dosage of A6 foam stabilizer is 0-10%, preferably 1-3%.

[0031] The dosage of A7 foaming agent is 0-2%, preferably 0.5-1%.

[0032] The B isocyanate component comprises one or more organic isocyanates;

[0033] The NCO content of the B isocyanate component is 20-50 wt.%, and the viscosity at 25°C is 1-5000 mPa·s, preferably 50-600 mPa·s;

[0034] The B isocyanate component is selected from one or a mixture of organic isocyanate monomers, isocyanate prepolymers, polyisocyanates, and isocyanate modified products, and the functionality of the isocyanate component is 2 to 5.

[0035] In some embodiments of the method according to the present invention, the B isocyanate component includes, but is not limited to, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), naphthalene diisocyanate (NDI), terephthalic diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CHDI), and phenyl diisocyanate. 1,6-Hexamethylene diisocyanate (XDI), cyclohexanedimethyl diisocyanate (HXDI), trimethyl-1,6-hexamethylene diisocyanate (TMHDI), tetramethyl-m-phenylenediamine diisocyanate (TMXDI), norbornane diisocyanate (NBDI), dimethylbiphenyl diisocyanate (TODI), methylcyclohexyl diisocyanate (HTDI), tetramethylene diisocyanate, 2-methylpentamethylene diisocyanate, dodecamethyl diisocyanate, 4,4'-diisocyanate Oxycyanate-3,3'-dimethyldicyclohexylmethane, 4,4'-diisocyanate-2,2-dicyclohexylpropane, poly(hexamethylene diisocyanate), octamethylene diisocyanate, toluene-α,4-diisocyanate, 2,4,6-trimethyl-1,3-phenyl diisocyanate, 4-chloro-6-methyl-1,3-phenyl diisocyanate, poly[1,4-phenyl diisocyanate-co-poly(1,4-butanediol)]diisocyanate, poly(tetrafluoroethylene oxide-co-difluoromethyleneoxy)α,ω- Diisocyanates, 1,4-butane diisocyanate, 1,8-octane diisocyanate, 1,3-bis(1-isocyanate-1-methylethyl)benzene, 3,3'-dimethyl-4,4'-biphenyl diisocyanate, naphthalene-1,5-diisocyanate, 1,3-phenyl diisocyanate, 1,4-phenyl diisocyanate, 4,4'-, 2,4'- or 2,2'-diphenylmethane diisocyanate or mixtures of these isomers, 4,4'-, 2,4'- or 2,2'-diisocyanate-2,The mixture contains at least one of 2-diphenylpropane, terephthalic acid diisocyanate, and prepolymers or modified products of the above isocyanates, preferably toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), naphthalene diisocyanate (NDI), terephthalic acid diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CHDI), terephthalic acid diisocyanate (XDI), or cyclohexane diisocyanate (HXDI). At least one of trimethyl-1,6-hexamethylene diisocyanate (TMHDI), tetramethyl-m-phenylenediethylene diisocyanate (TMXDI), norbornene diisocyanate (NBDI), dimethylbiphenyl diisocyanate (TODI), methylcyclohexyl diisocyanate (HTDI), and prepolymers or modified products of the above isocyanates, more preferably at least one of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), and prepolymers or modified products of the above isocyanates.

[0036] In this invention, the number of molar hydrogen atoms of the active hydrogen in the reactive isocyanate component A is 'a', the number of molar isocyanate groups in the isocyanate component B is 'b', and the isocyanate index R = b / a = 0.8–2. In some embodiments of the method according to this invention, 1–1.2 is preferred. It should be noted that the active hydrogen atom refers to a hydrogen atom capable of reacting with the isocyanate group.

[0037] In some embodiments of the method according to the present invention, the density of the cured polyurethane foam material is 0.1–0.8 g / cm³. 3 Preferably, it is 0.1–0.5 g / cm³. 3 .

[0038] In some embodiments of the method according to the invention, the polyurethane foam material is determined to be at least V0 by the UL94 plastic flammability test, wherein the width and thickness are 10 mm and 8 mm, respectively.

[0039] The polyurethane foam material exhibits good initial flowability, stable foaming state, excellent long-term foaming flowability, and rapid curing at room temperature, resulting in superior filling effect and efficiency. In some embodiments of the method according to the present invention, the foaming time of the foam material at room temperature is 3-4 minutes, and the viscosity is below 600 mPa·s within 0-5 minutes; in simulated filling experiments, the foam material demonstrates excellent potting and filling effect and high curing efficiency.

[0040] This invention also relates to the application of the polyurethane foam material, particularly suitable for filling and fixing gaps in battery packs and between battery cells.

[0041] The preparation method of component A of the polyurethane foam material is simple and suitable for industrial production. After mixing components A and B, the initial viscosity is low, the foaming is slow, the viscosity increase is gradual, and the curing is fast in the later stage, ensuring sufficient operation time during the filling of the foam material. At the same time, the curing efficiency is high, saving time and costs. The key to the realization of this invention lies in the use of specific high-activity polyethers and low-activity polyethers. On the one hand, high-activity polyether polyols and low-activity polyether polyols have certain incompatibilities. The mixing of the two reduces the interaction forces between their molecular chains, thereby obtaining a low-viscosity isocyanate reactive component A, ensuring excellent flowability of the foam material in the initial mixing stage. At the same time, high-activity polyether polyols and low-activity polyether polyols also have a certain activity difference. When components A and B are mixed, the main part that reacts with isocyanate in the early stage is the high-activity polyether polyol. The average functionality of the system is low. By adjusting the amount and ratio of the combined polyethers, the degree of reaction in the early stage is controlled to be lower than the gel point for a relatively long reaction time, thereby obtaining a relatively stable foaming state and viscosity increase trend, achieving long-term flowability. Furthermore, by utilizing the activity differences, incompatibility, and microphase separation characteristics of highly active and low-activity polyether polyols during the foaming process, a foam system with high open-cell structure and low water absorption (water absorption with skin <2%, water absorption without skin <10%) can be obtained. High open-cell foam allows for rapid heat dissipation, preventing internal heat accumulation. The lower temperature in the foam core prevents further catalytic reactions, thus ensuring slow initial foaming and maintaining a relatively low viscosity for a longer period. This results in excellent long-term foaming fluidity. Additionally, the preferred use of a delayed-type catalyst ensures strong gelation and rapid maturation in the later stages. In contrast, if the reaction system uses a combination of polyethers with good compatibility and similar reactivity, the average functionality of the system in the early stage is higher, the time to reach the gel point is shorter, and the viscosity increases faster. If the reaction rate in the early stage is reduced by adjusting the additives, this will inevitably increase the post-curing time and reduce the curing efficiency. Furthermore, under the same conditions, this system has poor cell opening, which leads to a faster temperature rise in the foam core. Although this ensures a low viscosity of the foamed material in the early stage, the accelerated reaction due to the higher temperature also results in a shorter low-viscosity time. In addition, the polyurethane foamed material has excellent thermal insulation and mechanical properties, making it suitable for filling spaces, especially for filling and fixing gaps in battery packs and between battery cells. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the tooling and glue injection point setup for testing the filling properties of polyurethane foam materials;

[0043] Figure 2 The results are the filling test results of Example 1, Comparative Example 1, Comparative Example 2 and Comparative Example 3 when there are no obstructions inside the tooling;

[0044] Figure 3 This is the filling test result of Example 1 when there are obstructions inside the tooling. Detailed Implementation

[0045] The present invention will be further described in detail below through specific embodiments, but it should not be construed as limiting the scope of the invention to the following examples. Various substitutions or modifications made based on ordinary technical knowledge and conventional methods in the art without departing from the above-described methodological spirit of the invention should be included within the scope of the invention. In this application, parts and percentages are generally by weight, unless otherwise specified.

[0046] The raw materials used in the examples are as follows:

[0047] Polyether polyol 1, glycerol-initiated, EO-polymerized, hydroxyl value 600 mg KOH / g, EO content 100 wt.%, EO end-capping rate 100%, viscosity 250–400 mPa·s;

[0048] Polyether polyol 2, glycerol-initiated, copolymerized with EO and PO, hydroxyl value 400 mg KOH / g, EO content 40 wt.%, EO end-capping rate 80%, viscosity 250-300 mPa·s;

[0049] Polyether polyol 3, glycerol-initiated, copolymerized with EO and PO, hydroxyl value 500 mg KOH / g, EO content 70 wt.%, EO end-capping rate 30%, viscosity 200-300 mPa·s;

[0050] Polyether polyol 4,1,2-propanediol is used as a starting material, copolymerized with EO and PO, with a hydroxyl value of 350 mg KOH / g, an EO content of 80 wt.%, an EO end-capping rate of 0%, and a viscosity of 200–300 mPa·s.

[0051] Polyether polyol 5, glycerol-initiated, copolymerized with EO and PO, hydroxyl value 42 mg KOH / g, EO content 80 wt.%, EO end-capping rate 60%, viscosity 900–1300 mPa·s;

[0052] Polyether polyol 6, glycerol-initiated, PO polymerized, hydroxyl value 168 mg KOH / g, EO content 0 wt.%, EO end-capping rate 0%, viscosity 200-300 mPa·s;

[0053] Polyether polyol 7, glycerol-initiated, PO polymerized, hydroxyl value 420 mg KOH / g, EO content 0 wt.%, EO end-capping rate 0%, viscosity 300-500 mPa·s;

[0054] Polyether polyol 8, glycerol-initiated, copolymerized with EO and PO, hydroxyl value 335 mg KOH / g, EO content 20 wt.%, EO end-capping rate 10%, viscosity 200-400 mPa·s;

[0055] Polyether polyol 9, sorbitol-initiated, PO polymerized, hydroxyl value 480 mg KOH / g, EO content 0 wt.%, EO end-capping rate 0%, viscosity 30000~35000 mPa·s;

[0056] Polyether polyol 10, glycerol-initiated, copolymerized with EO and PO, hydroxyl value 360 ​​mg KOH / g, EO content 10 wt.%, EO end-capping rate 80%, viscosity 200-400 mPa·s;

[0057] Catalyst: KC152 (triethylenediamine solution), Wanhua Chemical;

[0058] Flame retardant: Tris(2-chloropropyl) phosphate (TCPP);

[0059] Chain extender: DEG;

[0060] Foam stabilizer: B8002, purchased from Evonik.

[0061] Foaming agent: water.

[0062] Isocyanate component (B): WANNATE 82681, NCO content 31.5wt%, viscosity at 25℃ 200mPa·s, Wanhua Chemical.

[0063] The test methods or standards used in the examples and comparative examples are as follows:

[0064] The viscosity test standard is: GB / T 12008.8-92;

[0065] The standard for compressive strength testing is GB / T8813-2020;

[0066] The standard for tensile strength testing is GB / T 528-2009;

[0067] The standard for tensile modulus testing is GB / T 528-2009;

[0068] The standard for elongation at break is GB / T 528-2009;

[0069] The standard for impact strength testing is GB / T 1043-2008;

[0070] The standard for flexural modulus testing is GB / T 8812-2007;

[0071] The standard for bending strength testing is GB / T 8812-2007;

[0072] The standard for thermal conductivity testing is GB / T 10295;

[0073] The standard for vertical burning testing is GB / T2408 (UL94);

[0074] Fire test standard: GB / T31467.3.

[0075] The amounts of each component of the polyurethane foam material used in the examples and comparative examples are listed in Tables 1 and 2.

[0076] Table 1. Amounts (parts by mass) of each component in the examples.

[0077]

[0078]

[0079] Table 2 shows the dosage (parts by mass) of each component in the comparative examples.

[0080]

[0081] Method for testing polyurethane foam materials at 25℃: At 25℃, according to the types and amounts in Tables 1 and 2, component A is pre-mixed uniformly, and then components A and B are mixed uniformly. The viscosity and core temperature of the mixture at 25℃ are tested at different times after mixing. At the same time, the time when milky white foaming begins after mixing A and B is recorded. The test results are listed in Tables 3 to 5. In Tables 3 and 4, the blank content indicates that the viscosity of the corresponding example or comparative example is too high or has been cured and cannot be tested.

[0082] Table 3 shows the time to milky whitening and viscosity changes at different times after mixing components A and B in the examples.

[0083]

[0084]

[0085] Table 4 shows the time to milky whitening and viscosity changes at different times after mixing components A and B in the comparative example.

[0086]

[0087]

[0088] Table 5 shows the core temperature changes of the materials after mixing components A and B in the examples and comparative examples.

[0089]

[0090]

[0091] Method for testing the filling properties of polyurethane foam materials: Custom-made fixtures with dimensions of 600mm × 2mm × 200mm (length × width × height) Figure 1 (The tooling has flow obstructions inside, and three injection points are selected from the top gap.) According to the types and dosages in Tables 1 and 2, component A is pre-mixed uniformly. Then, components A and B, both at a material temperature of 25℃, are mixed uniformly. The mixture is then immediately injected into the tooling through the injection port. The curing time of the foam material at room temperature and the final filling effect are recorded, as shown in Table 6 below. Figure 2 and Figure 3 As shown.

[0092] Table 6. Room temperature curing time and filling effect of polyurethane foam in the filling test.

[0093]

[0094] Mold foam performance test: According to the types and dosages in Tables 1 and 2, component A was pre-mixed uniformly. Then, components A and B, both at a material temperature of 25℃, were mixed uniformly and poured into a sealed mold to prepare a foam with a density of 0.3 g / cm³. 3 The polyurethane foam material was tested, and its relevant properties were evaluated. The results are listed in Tables 7 and 8.

[0095] Table 7 shows the performance test results of the polyurethane foam materials in the examples.

[0096]

[0097] Table 8. Performance test results of polyurethane foam materials in the comparative examples.

[0098]

[0099]

[0100] As shown in the test results in the table above, the polyurethane potting foaming system described in this invention exhibits stable foaming over a relatively long period after the mixing of components A and B. The viscosity increase of the mixture is not significant, and the flowability during foaming is excellent, while the curing efficiency remains high. The resulting foamed material has the characteristics of high open-cell but low water absorption, and also demonstrates superior mechanical properties and flame-retardant and thermal insulation properties.

Claims

1. A polyurethane foam material, characterized by, The polyurethane foam material comprises an A isocyanate reactive component, a B isocyanate component; The A isocyanate reactive component comprises two or more polyols, at least including A1 high-activity polyether polyol and A2 low-activity polyether polyol; The A1 high-activity polyether polyol has a functionality of 2-5, a hydroxyl value of 250-800 mgKOH / g, and an EO content of 40-100 wt.% in the molecular structure, and an EO end-capping rate of ≥30%. The A2 low-activity polyether polyol has a functionality of 2-8, a hydroxyl value of 20-600 mgKOH / g, and an EO content of 0-20 wt.% in the molecular structure, and an EO end-capping rate of ≤20%. The content of the A1 high-activity polyether polyol is 25-90 wt.% based on the total mass of the A isocyanate reactive component, and the content of the A2 low-activity polyether polyol is 10-45%.

2. The polyurethane foam according to claim 1, wherein The A1 high-activity polyether polyol has a functionality of 3-5 and a hydroxyl value of 320-800 mgKOH / g.

3. The polyurethane foam according to claim 1, wherein The A1 high-activity polyether polyol has a viscosity of 1-5000 mPa·s at 25℃, and the A2 low-activity polyether polyol has a viscosity of 1-50000 mPa·s at 25℃.

4. The polyurethane foam according to claim 3, wherein The A1 high-activity polyether polyol has a viscosity of 50-500 mPa·s at 25℃, and the A2 low-activity polyether polyol has a viscosity of 50-1000 mPa·s at 25℃.

5. The polyurethane foam according to claim 1, wherein The content of the A1 high-activity polyether polyol is 35-80 wt.% based on the total mass of the A isocyanate reactive component. The content of the A2 low-activity polyether polyol is 15-35%.

6. The polyurethane foam according to claim 1, wherein The A isocyanate reactive component further comprises an A3 catalyst, and the A3 catalyst is selected from heat- or temperature-sensitive, delayed-type catalysts.

7. The polyurethane foam according to claim 6, wherein The A3 catalyst includes at least one of triethylenediamine, pentamethyldialkylene triamine, tetramethylalkylene diamine, bis(dimethylaminoethyl) ether, cyclohexylmethyl tertiary amine, stannous octoate, stannous oleate, tin laurate, dimethyltin dilaurate, dibutyltin dilaurate, dibutyltin dithiol, bismuth salts of naphthenic acid, bismuth salts of neodecanoic acid, and bismuth salts of cyclohexane acid.

8. The polyurethane foam according to claim 1, wherein The A isocyanate reactive component further comprises an A4 flame retardant, and the A4 flame retardant is a liquid flame retardant having a viscosity of 1-2000 mPa·s at 25℃.

9. The polyurethane foam according to claim 8, wherein The A4 flame retardant includes at least one of tris(2-chloroethyl) phosphate, tris(2,3-dichloropropyl) phosphate, dimethyl methylphosphonate, tris(2-chloropropyl) phosphate, cresyl phosphate, and cresyldiphenyl phosphate.

10. The polyurethane foam according to claim 1, wherein The A isocyanate reactive component further comprises an A5 chain extender.

11. The polyurethane foam according to claim 10, wherein The A5 chain extender includes at least one of glycerol, trimethylolpropane, trihydroxymethyl ethane, 1,2,6-hexanetriol, diethylene glycol, dipropylene glycol, methylpropanediol, 1,4-butanediol, 1,3-butanediol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-cyclohexanol, 1,6-hexanediol, diethanolamine, triethanolamine, and triisopropanolamine.

12. The polyurethane foam according to claim 1, wherein The A isocyanate-reactive component further comprises an A6 foam stabilizer comprising at least one of organosilicon-based, polyol-based, silicone-based, sulfonated fatty alcohols, sulfonated fatty acids, and other non-ionic surfactants.

13. The polyurethane foam according to claim 1, wherein The A isocyanate-reactive component further comprises an A7 blowing agent.

14. The polyurethane foam according to claim 13, wherein The A7 blowing agent is water.

15. The polyurethane foam according to any of claims 1 to 14, wherein comprises, based on the total mass of the A isocyanate-reactive component: A1 high activity polyether polyol in an amount of 25 to 90%; A2 low activity polyether polyol in an amount of 10 to 45%; A3 catalyst in an amount of 0 to 1%; A4 flame retardant in an amount of 0 to 50%; A5 chain extender in an amount of 0 to 30%; A6 foam stabilizer in an amount of 0 to 10%; A7 blowing agent in an amount of 0 to 2%.

16. The polyurethane foam according to any of claims 1 to 14, wherein comprises, based on the total mass of the A isocyanate-reactive component: A1 high activity polyether polyol in an amount of 35 to 80%; A2 low activity polyether polyol in an amount of 15 to 35%; A3 catalyst in an amount of 0.01 to 0.1%; A4 flame retardant in an amount of 5 to 30%; A5 chain extender in an amount of 5 to 15%; A6 foam stabilizer in an amount of 1 to 3%; A7 blowing agent in an amount of 0.5 to 1%.

17. The polyurethane foam according to claim 15, wherein comprises, based on the total mass of the A isocyanate-reactive component: A1 high activity polyether polyol in an amount of 40 to 75%; A2 low activity polyether polyol in an amount of 20 to 30%; A3 catalyst in an amount of 0 to 1%; A4 flame retardant in an amount of 10 to 20%; A5 chain extender in an amount of 8 to 10%; A6 foam stabilizer in an amount of 0 to 10%; A7 blowing agent in an amount of 0 to 2%.

18. The polyurethane foam according to any one of claims 1 to 14, wherein The B isocyanate component has an NCO content of 20 to 50 wt.%, a viscosity of 1 to 5000 mPa-s at 25°C; isocyanate index R = 0.8 to 2.

19. The polyurethane foam according to claim 18, wherein isocyanate index R = 1 to 1.2.

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