A polyurethane rigid foam composition, and a method of making and use thereof

Abstract

The application discloses a kind of polyurethane rigid foam composition and preparation method and purposes, and it includes the component A and component B mixed by mass ratio 1:1.1-2, component A includes polyester polyol, polyether polyol, polyolefin polyol, chain extender, flame retardant, foam stabilizer, catalyst, foaming agent, toughening agent, crosslinking agent;Component B is polyphenylmethane polyisocyanate.The polyurethane rigid foam prepared by the application has excellent strength and toughness, and the thermal insulation performance, heat resistance and flame retardancy are significantly increased, which can be used for pipeline, tank thermal insulation and cold preservation, and can meet the use requirements of other harsh environments.

Description

Technical Field

[0001] This invention relates to the field of polyurethane materials, and more specifically to a composition for preparing toughened rigid polyurethane foam materials and rigid polyurethane foam prepared from said composition. Background Technology

[0002] Rigid polyurethane foam has been widely used in transportation, construction, refrigeration and freezing equipment and cold storage, pipeline and tank insulation, and military and aerospace industries due to its outstanding mechanical and thermal insulation properties. In recent years, with the development of technology and the increasingly harsh environments in which materials are used, there are increasingly higher requirements for certain properties of materials. In the case of rigid polyurethane foam, in addition to ensuring a low thermal conductivity, the material needs to have good mechanical properties (compressive strength, impact strength, etc.).

[0003] The brittleness of rigid polyurethane foam limits its application in certain fields. Existing technologies include introducing elastic particles such as rubber particles into rigid polyurethane foam to improve the material's toughness. However, these elastic particles are prone to aggregation, leading to stress concentration and material failure. Another method is to introduce a large amount of polyols containing flexible chains. Although this improves the material's toughness, the large-scale introduction of flexible chain polyols significantly reduces the compressive strength, tensile strength, and dimensional stability of the rigid polyurethane foam itself.

[0004] To improve the toughening effect of rigid polyurethane foam, existing technologies have conducted some research on polyurethane raw materials and obtained corresponding solutions. For example, CN105713166A provides a solution for strengthening and toughening rigid polyurethane foam with organic-inorganic hybrid materials, but its density is relatively high, and its thermal insulation performance is significantly reduced. CN104325588A provides a method for strengthening and toughening polyurethane foam with ultra-high molecular weight polyethylene fibers, but ultra-high molecular weight polyethylene will aggregate, leading to a reduction in the strengthening and toughening effect. CN112574551A provides a solution using modified nano-calcium carbonate and fiber-reinforced rigid polyurethane foam. Although it has excellent mechanical properties and thermal stability, its density increases significantly and its thermal insulation performance and toughness decrease. The paper "Preparation and Performance Study of Underwater Thermal Insulation High-Density Rigid Polyurethane Foam" provides a solution for adjusting the amount of raw materials polyether 4110 and polyether 3050 to meet performance requirements. Although it meets the application requirements to a certain extent, it is greatly affected by the main polyether and cannot simultaneously increase the toughness and strength of the foam, which is a significant limitation. Summary of the Invention

[0005] The technical problem to be solved by this invention is how to prepare rigid polyurethane foam with high strength and good toughness.

[0006] To address the aforementioned problems, this invention provides a rigid polyurethane foam composition and its preparation method. By introducing a thermotropic liquid crystal diol containing active hydrogen as a chain extender, the polyurethane foam exhibits ultra-high thermal stability and increases foam strength. Simultaneously, the synergistic effect of hydroxyl-terminated polybutadiene and polyolefin toughening agents improves the problem of the foam's hardness and brittleness by enhancing the flexibility of the foam skeleton molecular chains and its "island" structure. The foam possesses enhanced compressive strength and toughness while maintaining a low thermal conductivity, and forms a high-temperature phase change material, further improving the material's thermal insulation performance under harsh high-temperature conditions.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A rigid polyurethane foam composition comprising component A and component B, wherein the mass ratio of component A to component B is 1:1.1-2, preferably 1:1.1-1.8;

[0009] The raw materials in component A include, by mass, the following:

[0010]

[0011]

[0012] Component B is polyphenylmethane polyisocyanate.

[0013] In this invention, the polyester polyol is selected from aromatic polyester polyols, and the monomer of the aromatic polyester polyol is an aromatic dicarboxylic acid (or acid anhydride, ester) and a diol (and / or polyol). The aromatic dicarboxylic acid (or acid anhydride, ester) is preferably one or more of phthalic anhydride, terephthalic acid, and phthalic acid.

[0014] Preferably, the aromatic polyester polyol is selected from one or more of PS-3152, PS-2452, PS-2002 from Nanjing Jinling Stepan Chemical Co., Ltd. and CF-6300, CF-6200 from Jiangsu Fusheng New Materials Co., Ltd., and more preferably PS-3152 from Nanjing Jinling Stepan and / or CF-6200 from Jiangsu Fusheng.

[0015] In this invention, the polyether polyol is selected from polyether polyol 1 and / or polyether polyol 2;

[0016] The polyether polyol 1 has glycerol as the initiator, propylene oxide as the polymerization monomer, and a hydroxyl value of 100-600 mgKOH / g, preferably one or more of Wanhua Chemical's A303, A305, A307, and A310.

[0017] The polyether polyol 2 has sorbitol and / or sucrose as the initiator, propylene oxide as the polymerizing monomer, and a hydroxyl value of 300-600 mgKOH / g, preferably one or more of Wanhua Chemical SYPG-086, A29-1 and Tianjin Sanshi Chemical 450L.

[0018] In this invention, the polyolefin polyol is hydroxyl-terminated polybutadiene;

[0019] Preferably, the polymer monomer of the hydroxyl-terminated polybutadiene is butadiene with a number average molecular weight of 500-5000, and more preferably a number average molecular weight of 1000-2000.

[0020] In this invention, the chain extender is selected from thermotropic liquid crystal small molecule diols containing active hydrogen, with a molecular weight of 400-1000.

[0021] Preferably, the thermotropic liquid crystal diol containing active hydrogen has a structure as shown in Formula 1:

[0022] In the formula, R represents a rigid group in different substitution positions and different types of diphenols, preferably...

[0023] R' represents the methylene group in chlorohydrins with different methylene contents, preferably... n takes the value of an integer from 2 to 6;

[0024] Preferably, the thermotropic liquid crystal small molecule diol containing active hydrogen is prepared by reacting chlorohydrin with a diphenol containing a rigid group; the chlorohydrin is selected from one or more of 2-chloroethanol, 3-chloro-1-propanol, 4-chloro-1-butanol, 5-chloro-1-pentanol, and 6-chloro-1-hexanol; the diphenol containing a rigid group is prepared by reacting 4,4'-difluorobenzophenone with a diphenol containing an aromatic ring, wherein the diphenol containing an aromatic ring is selected from one or more of hydroquinone, catechol, resorcinol, biphenol, bisphenol A, bisphenol S, and bisphenol F;

[0025] The method for preparing a thermotropic liquid crystal small molecule diol chain extender containing active hydrogen by reacting chlorohydrin with a diphenol containing a rigid group, as described in this invention, is known in the art. Those skilled in the art can refer to any of the disclosed methods to prepare the diol with the desired structure according to actual needs. In some embodiments, the preparation method is as follows: reacting 4,4'-difluorobenzophenone with a diphenol containing an aromatic ring to generate a diphenol with a rigid structure containing a continuous aromatic ring; then reacting the obtained diphenol with 6-chloro-1-hexanol in ethanol to obtain the thermotropic liquid crystal small molecule diol containing active hydrogen. For details, please refer to "Novel Poly(ether ketone)arylates: Synthesis, Characterization and Properties" and "Thermal and Rheological Properties of a Liquid-Crystalline Polyurethane".

[0026] More preferably, the chain extender is selected from bis(4-(4-((6-hydroxyhexyl)oxy)phenoxy)phenyl) ketone and / or bis(4-((4'-((6-hydroxyhexyl)oxy)-[1,1'-biphenyl]-4-acyl)phenoxy) ketone; wherein the bis(4-(4-((6-hydroxyhexyl)oxy)phenoxy)phenyl) ketone is a small molecule diol obtained by reacting bis[4-(4-hydroxyphenoxy)phenyl] ketone with 6-chloro-1-hexanol, and the bis(4-((4'-((6-hydroxyhexyl)oxy)-[1,1'-biphenyl]-4-acyl)phenoxy) ketone is a small molecule diol obtained by reacting bis(4-(4'-hydroxy-[1,1'-biphenyl]-4-acyl)phenoxy) ketone with 6-chloro-1-hexanol.

[0027] In this invention, the flame retardant is an alkyl phosphate flame retardant, selected from one or more of tris(1-chloroethylpropyl) phosphate (TCPP), triethyl phosphate (TEP), dimethyl methyl phosphate (DMMP), and tris(2-chloroethyl) phosphate (TECP).

[0028] In this invention, the foam stabilizer is selected from one or more of Momentive Y-16368, L6620, and L6100, with Momentive Y-16368 being preferred.

[0029] In this invention, the catalyst is selected from one or more of amine catalysts and metal catalysts. The amine catalyst is preferably selected from one or more of N,N-dimethylcyclohexylamine, pentamethyldiethylenetriamine, N,N-dimethylbenzylamine, 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine, bis(2-dimethylaminoethyl) ether, and triethylenediamine. The metal catalyst is preferably selected from one or more of organotin and potassium acetate.

[0030] In this invention, the foaming agent is selected from one or more of HCFC-141b, HFC-245fa, and HFC-365mfc.

[0031] In this invention, the toughening agent is a copolymer of ethylene and α-olefin as monomers, wherein the α-olefin is preferably selected from butene, hexene, and octene;

[0032] Preferably, the toughening agent is one or more selected from DOW's 8003, 8110, 8150, Mitsui Chemicals' DF610, DF640, and more preferably DOW's 8003.

[0033] In this invention, the crosslinking agent is selected from one or more of dicumyl peroxide (DCP), 2,5-dimethyl-2,5-di-tert-butylperoxyhexane, and trimethylolpropane trimethacrylate, with dicumyl peroxide (DCP) being preferred.

[0034] In this invention, the viscosity of the polyphenylmethane polyisocyanate is 150-800 cp, preferably one or more of Wanhua Chemical's PM-200, PM-400, and PM-700.

[0035] The present invention also provides a method for preparing the aforementioned rigid polyurethane foam, comprising the following steps:

[0036] (1) Mix toughening agent, crosslinking agent and foaming agent to obtain liquid 1;

[0037] (2) Mix polyester polyol, polyether polyol, polyolefin polyol, flame retardant, chain extender, foam stabilizer and catalyst to obtain liquid 2;

[0038] (3) Mix the above liquid 1 and liquid 2 to obtain component A;

[0039] (4) Mix component A and component B polyphenylmethane polyisocyanate and foam to obtain rigid polyurethane foam.

[0040] In the method of the present invention, in step (4), the foaming temperature is 10-30℃, preferably 15-25℃; the foaming is carried out under stirring, the stirring time is 3-15s, preferably 5-10s, and the maturation time after stirring is 12-36h, preferably 18-24h.

[0041] The rigid polyurethane foam prepared by this invention has excellent strength and toughness, and its thermal insulation, heat resistance and flame retardancy are significantly improved. It can be used for thermal insulation and cold insulation of pipelines and tanks, and can meet the needs of other harsh environments.

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0043] 1) This invention uses polyolefin elastomer to toughen rigid polyurethane foam. The heat generated during the foaming process raises the temperature, thereby causing DCP to initiate in-situ crosslinking of polyolefin, which improves performance and greatly reduces reaction energy consumption. Furthermore, the use of polyolefin elastomer to toughen rigid polyurethane foam gives the material high strength and toughness over a wide temperature range.

[0044] 2) This invention uses rigid main chain polyester polyol, high-functionality polyether polyol and small molecule chain extender containing rigid groups to give polyurethane foam high skeleton strength. Further use of low-functionality polyether polyol and hydroxyl-terminated polybutadiene gives the foam skeleton a certain degree of inherent toughness. Introducing alkyl chains into the foam skeleton using a small amount of hydroxyl-terminated polybutadiene improves the compatibility of the polyolefin toughening agent with the foam and enhances its dispersion and distribution, thereby improving the performance of rigid polyurethane foam. During the polyurethane foaming process, the introduced small-molecule liquid crystal chain extender, due to the foam stretching process and the molecular alignment along the foaming direction, reacts with isocyanate and enters the polyurethane molecular chain skeleton, providing in-situ reinforcement and significantly increasing the strength of the rigid polyurethane foam. Furthermore, after material molding, the numerous rigid groups and hydrogen bonds further enhance the performance of the rigid polyurethane foam, and the introduction of polyaromatic ring structures improves the foam's flame retardancy. Moreover, the chain extender used in this invention has an aromatic ether ketone molecular structure, giving the foam higher strength and excellent high-temperature charring properties, further improving its flame retardancy.

[0045] 3) Due to the ultra-rigid structure of the chain extender used in this invention, the polyurethane foam has ultra-high thermal stability. Furthermore, the rigid polyurethane skeleton encapsulates the polyolefin elastomer particles, resulting in micro-phase separation and forming a "core-shell-like structure". Under high-temperature conditions, the micro-crosslinked polyolefin micro-regions partially melt, which can serve as an "energy storage-like" material. This can further reduce the thermal conductivity and provide corresponding insulation, preventing the temperature from rising further. Under low-temperature conditions, the polyolefin micro-regions undergo phase change, preventing the temperature from dropping rapidly. While retaining the insulation properties of traditional polyurethane foam, the introduction of polyolefins for toughening allows it to function as an insulation material in harsh environments. Detailed Implementation

[0046] The present invention will be further described below with reference to embodiments. These embodiments are only for illustration and do not limit the scope of the present invention.

[0047] Information on the main raw material sources used in the embodiments of this invention; unless otherwise specified, all other raw materials are common commercially available materials:

[0048] Polyester polyols: PS3152, purchased from Nanjing Jinling Stepan Chemical Co., Ltd.; CF-6200, purchased from Jiangsu Fusheng New Materials Co., Ltd.

[0049] Polyether polyols: A29-1, SYPG-086, A303, A305, A307, A310, purchased from Wanhua Chemical; 450L, purchased from Tianjin Sanshi Chemical.

[0050] Polyolefin polyol: Hydroxyl-terminated polybutadiene LBH-2000, purchased from Cray Valley;

[0051] Chain extenders: bis(4-(4-((6-hydroxyhexyl)oxy)phenoxy)phenyl) methyl ketone (chain extender 1) and bis(4-((4'-((6-hydroxyhexyl)oxy)-[1,1'-biphenyl]-4-acyl)phenoxy) methyl ketone (chain extender 2). The preparation methods for both are based on "Novel Poly(ether ketone)arylates: Synthesis, Characterization and Properties" and "Thermal and Rheological Properties of a Liquid-Crystalline Polyurethane," and the steps are as follows:

[0052] Hydroquinone was dissolved in N-methylpyrrolidone. After heating to 40°C, an anhydrous potassium carbonate (8-10:10 ratio with hydroquinone) was added, and the reaction proceeded until the system turned black. Then, 4,4'-difluorobenzophenone (1:2 mass ratio with hydroquinone) and toluene were added. The system was slowly heated to 140°C for 7 hours, and then heated to 170°C for 1 hour. Toluene was removed, and after precipitation and pH adjustment, the reaction product was obtained. The reaction product was placed in anhydrous ethanol, and the temperature was slowly raised to 70°C. Trace amounts of KI and a certain proportion of NaOH (1-1.1:2.5 mass ratio with the reaction product) were added. Then, a certain volume of 6-chloro-1-hexanol (2-2.1:1 molar ratio with the reaction product) was added to the system, and the temperature was slowly raised to 80°C for 24 hours. After precipitation and pH adjustment, chain extender 1 was obtained.

[0053] Following the method for chain extender 1 described above, chain extender 2 was prepared by replacing hydroquinone with biphenyl hydroquinone.

[0054] Flame retardants: TCPP, TEP, TCEP, all purchased from Bayer;

[0055] Foam stabilizers: Y-16368, L6620, and L6100, all purchased from Momentive.

[0056] Catalysts: Pentamethyldiethylenetriamine PC5, N,N-dimethylbenzylamine BDMA, potassium acetate LCM-1, 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine PC41;

[0057] Toughening agent: 8003, purchased from DOW.

[0058] Crosslinking agent: DCP, purchased from Shandong Ruihuang Chemical Co., Ltd.;

[0059] Foaming agents: 141b, 245fa, and 365mfc, all purchased from Honeywell;

[0060] Polyphenylmethane polyisocyanates: PM-200, PM-400, PM-700, purchased from Wanhua Chemical.

[0061] The performance testing method used in this embodiment of the invention:

[0062] Density: Tested according to GB / T 9641-1988.

[0063] Compressive strength: Tested in accordance with GB / T 8813-2020.

[0064] Tensile strength and elongation at break: tested in accordance with GB 9641-1988.

[0065] Closed-cell ratio: Tested according to GB / T 10799-2008.

[0066] Oxygen index: tested according to GB / T 2406.2-2009;

[0067] Thermal conductivity: Tested according to GB / T 3399-1982.

[0068] Examples 1-8

[0069] Polyurethane rigid foam composition: Prepare the materials in Examples 1-8 according to the composition raw materials and dosages in Table 1 below.

[0070] The rigid polyurethane foams of Examples 1-8 were prepared according to the following method:

[0071] (1) Mix toughening agent, crosslinking agent and foaming agent to obtain liquid 1;

[0072] (2) Mix polyester polyol, polyether polyol, polyolefin polyol, flame retardant, chain extender, foam stabilizer and catalyst to obtain liquid 2;

[0073] (3) Mix the above liquid 1 and liquid 2 to obtain component A;

[0074] (4) Mix component A and component B polyphenylmethane polyisocyanate and foam to obtain rigid polyurethane foam.

[0075] The foaming method is manual mechanical stirring foaming: before mechanical stirring, the temperature of each component is kept at 25°C, the stirring time is 5s, and after stirring, it is cured for 24h to obtain the polyurethane rigid foam of Examples 1-8.

[0076] Table 1 shows the types and amounts (g) of raw materials used in the examples.

[0077]

[0078]

[0079] Comparative Example 1

[0080] The rigid polyurethane foam corresponding to Comparative Example 1 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the chain extender 1 was replaced with Stepan's polyester polyol PS3152.

[0081] Comparative Example 2

[0082] The rigid polyurethane foam corresponding to Comparative Example 2 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the toughening agent and crosslinking agent were both replaced with Stepan's polyester polyol PS3152.

[0083] Comparative Example 3

[0084] The rigid polyurethane foam corresponding to Comparative Example 3 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the chain extender 1, toughening agent and crosslinking agent were all replaced with Stepan's polyester polyol PS3152.

[0085] Comparative Example 4

[0086] The rigid polyurethane foam corresponding to Comparative Example 4 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the chain extender 1 was replaced with 4,4'-bis(6-hydroxyhexyloxy)biphenyl.

[0087] Comparative Example 5

[0088] The rigid polyurethane foam corresponding to Comparative Example 5 was prepared according to the raw materials and amounts in Example 1. The difference between the two is that the polyolefin polyol hydroxyl-terminated polybutadiene LBH-2000 was replaced with BASF's polyether diol PolyTHF-2000.

[0089] Comparative Example 6

[0090] The rigid polyurethane foam corresponding to Comparative Example 6 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the toughening agent polyolefin elastomer 8003 was replaced with SBS adhesive powder SH-600 from Dongguan Shenghao.

[0091] Comparative Example 7

[0092] The rigid polyurethane foam corresponding to Comparative Example 7 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the chain extender 1 was replaced with bis[4-(4-hydroxyphenoxy)phenyl] ketone.

[0093] Comparative Example 8

[0094] The rigid polyurethane foam corresponding to Comparative Example 8 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the chain extender 1 was replaced with bis(4-(4'-hydroxy-[1,1'-biphenyl]-4-acyl)phenoxy) methyl ketone.

[0095] Comparative Example 9

[0096] The rigid polyurethane foam corresponding to Comparative Example 9 was prepared according to the raw materials and dosages in Example 1, the difference being that chain extender 1 was replaced with 6-chloro-1-hexanol.

[0097] Comparative Example 10

[0098] The rigid polyurethane foam corresponding to Comparative Example 10 was prepared according to the raw materials and dosages in Example 1. The difference between the two is that the chain extender 1 was replaced with the non-thermotropic liquid crystal small molecule diol 6-[4-[2-(4-methylphenyl)azo]phenyl]-1-hexanol.

[0099] The density, compressive strength, tensile strength, elongation at break, closed-cell ratio, oxygen index, and thermal conductivity of the rigid polyurethane foams prepared in each embodiment and comparative example were tested, and the results are shown in Table 2.

[0100] Table 2 Foam Performance Test Data

[0101]

[0102]

[0103] The foam test data in Table 2 clearly show that introducing chain extender 1, chain extender 2 and polyolefin toughening agent into the polyurethane rigid foam composition can significantly improve the strength and toughness of the foam, and significantly increase its thermal insulation performance, heat resistance and flame retardancy, which can meet the needs of pipeline and tank insulation and other harsh environments.

[0104] The above description is only a preferred embodiment of the present invention. It should be noted that any other improvements or additions made by those skilled in the art without departing from the present invention should be within the scope of protection of the present invention.

Claims

1. A rigid polyurethane foam composition, characterized in that, It includes component A and component B, wherein the mass ratio of component A to component B is 1:1.1-2; The raw materials in component A include, by mass, the following: 20-50 parts of polyester polyol; 20-60 parts of polyether polyol; 2-10 parts of polyolefin polyol; 1-2 parts chain extender; 0-10 parts flame retardant; Foam stabilizer 0-3 parts; Catalyst 0.5-5 parts; 5-25 parts of foaming agent; 1-3 parts toughening agent; Crosslinking agent 0.0001-0.0002 parts; The polyolefin polyol is hydroxyl-terminated polybutadiene; The chain extender is selected from thermotropic liquid crystal small molecule diols containing active hydrogen, and the thermotropic liquid crystal small molecule diols containing active hydrogen have the structure shown in Formula 1: (1), In the formula, R represents a rigid group in the diphenol, selected from... , , , , , , ; R' represents the methylene group in chlorohydrin; The toughening agent is a copolymer of ethylene and α-olefin as monomers, wherein the α-olefin is selected from butene, hexene, and octene; The crosslinking agent is selected from one or more of dicumyl peroxide, 2,5-dimethyl-2,5-di-tert-butylperoxyhexane, and trimethylolpropane trimethacrylate. Component B is polyphenylmethane polyisocyanate.

2. The rigid polyurethane foam composition according to claim 1, characterized in that, The raw materials in component A include, by mass, the following: 30-40 parts of polyester polyol; 30-50 parts of polyether polyol; 3-5 parts of polyolefin polyol; Chain extender 1.2-1.8 parts; 3-8 parts flame retardant; 1-2 parts foam stabilizer; 1-4 parts catalyst; 10-15 parts of foaming agent; 1-2 parts toughening agent; Crosslinking agent 0.0001-0.0002 parts.

3. The rigid polyurethane foam composition according to claim 1, characterized in that, The mass ratio of component A to component B is 1:1.1-1.

8.

4. The rigid polyurethane foam composition according to claim 1, characterized in that, The polyester polyol is selected from aromatic polyester polyols, and the monomer of the aromatic polyester polyol is an aromatic dicarboxylic acid or an aromatic dicarboxylic acid anhydride, an aromatic dicarboxylic acid ester and a polyol.

5. The rigid polyurethane foam composition according to claim 4, characterized in that, The aromatic dicarboxylic acid or aromatic dicarboxylic acid anhydride is selected from one or more of phthalic anhydride, terephthalic acid, and phthalic acid.

6. The rigid polyurethane foam composition according to claim 4, characterized in that, The aromatic polyester polyol is selected from one or more of PS-3152, PS-2452, and PS-2002 from Nanjing Jinling Stepan Chemical Co., Ltd., and CF-6300 and CF-6200 from Jiangsu Fusheng New Materials Co., Ltd.

7. The rigid polyurethane foam composition according to claim 1, characterized in that, The polyether polyol is selected from polyether polyol 1 and / or polyether polyol 2; The polyether polyol 1 has glycerol as the initiator, propylene oxide as the polymerizing monomer, and a hydroxyl value of 100-600 mgKOH / g. The polyether polyol 2 has sorbitol and / or sucrose as the initiator, propylene oxide as the polymer monomer, and a hydroxyl value of 300-600 mg KOH / g.

8. The rigid polyurethane foam composition according to claim 7, characterized in that, The polyether polyol 1 is selected from one or more of Wanhua Chemical's A303, A305, A307 and A310.

9. The rigid polyurethane foam composition according to claim 7, characterized in that, The polyether polyol 2 is selected from one or more of Wanhua Chemical SYPG-086, A29-1 and Tianjin Sanshi Chemical 450L.

10. The rigid polyurethane foam composition according to claim 1, characterized in that, The number-average molecular weight of the hydroxyl-terminated polybutadiene is 500-5000.

11. The rigid polyurethane foam composition according to claim 10, characterized in that, The number-average molecular weight of the hydroxyl-terminated polybutadiene is 1000-2000.

12. The rigid polyurethane foam composition according to claim 1, characterized in that, The thermotropic liquid crystal diol containing active hydrogen has a molecular weight of 400-1000.

13. The rigid polyurethane foam composition according to claim 1, characterized in that, In the structure shown in Equation 1, R' is represented as n takes the value of an integer from 2 to 6.

14. The rigid polyurethane foam composition according to claim 1, characterized in that, The thermotropic liquid crystal small molecule diol containing active hydrogen is prepared by reacting chlorohydrin with a diphenol containing a rigid group. The chlorohydrin is selected from one or more of 2-chloroethanol, 3-chloro-1-propanol, 4-chloro-1-butanol, 5-chloro-1-pentanol, and 6-chloro-1-hexanol; The rigid-group-containing diphenol is prepared by reacting 4,4'-difluorobenzophenone with a diphenol containing an aromatic ring, wherein the diphenol containing an aromatic ring is selected from one or more of hydroquinone, catechol, resorcinol, biphenyl, bisphenol A, bisphenol S and bisphenol F.

15. The rigid polyurethane foam composition according to claim 1, characterized in that, The chain extender is selected from bis(4-(4-((6-hydroxyhexyl)oxy)phenoxy)phenyl) methyl ketone and / or bis(4-((4'-((6-hydroxyhexyl)oxy)-[1,1'-biphenyl]-4-acyl)phenoxy) methyl ketone.

16. The rigid polyurethane foam composition according to claim 1, characterized in that, The flame retardant is an alkyl phosphate flame retardant, selected from one or more of tris(1-chloro-2-propyl) phosphate, triethyl phosphate, dimethyl methyl phosphate, and tris(2-chloroethyl) phosphate; The foam stabilizer is selected from one or more of Momentive Y-16368, L6620, and L6100; The catalyst is selected from one or more of amine catalysts and metal catalysts; The foaming agent is selected from one or more of HCFC-141b, HFC-245fa, and HFC-365mfc.

17. The rigid polyurethane foam composition according to claim 16, characterized in that, The amine catalyst is selected from one or more of N,N-dimethylcyclohexylamine, pentamethyldiethylenetriamine, N,N-dimethylbenzylamine, 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine, bis(2-dimethylaminoethyl) ether, and triethylenediamine; the metal catalyst is selected from one or more of organotin and potassium acetate.

18. The rigid polyurethane foam composition according to claim 16, characterized in that, The toughening agent is one or more selected from DOW's 8003, 8110, 8150, Mitsui Chemicals' DF610, DF640.

19. The rigid polyurethane foam composition according to claim 1, characterized in that, The viscosity of the polyphenylmethane polyisocyanate is 150-800 cp.

20. The rigid polyurethane foam composition according to claim 19, characterized in that, The polyphenylmethane polyisocyanate is selected from one or more of Wanhua Chemical's PM-200, PM-400, and PM-700.

21. A method for preparing the rigid polyurethane foam composition according to any one of claims 1-20, characterized in that the step... include: (1) Mix the toughening agent, crosslinking agent and foaming agent to obtain liquid 1; (2) Mix polyester polyol, polyether polyol, polyolefin polyol, flame retardant, chain extender, foam stabilizer and catalyst to obtain liquid 2; (3) Mix the above liquid 1 and liquid 2 to obtain component A; (4) Mix component A and component B polyphenylmethane polyisocyanate and foam to obtain rigid polyurethane foam.

22. The preparation method according to claim 21, characterized in that, In step (4), the foaming temperature is 10-30℃; the foaming is carried out under stirring for 3-15 seconds, and the maturation time after stirring is 12-36 hours.

23. The preparation method according to claim 22, characterized in that, The foaming process takes place at a temperature of 15-25℃.

24. The preparation method according to claim 22, characterized in that, The foaming is carried out under stirring for 5-10 seconds, and the maturation time after stirring is 18-24 hours.

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