Modified rigid polyurethane foam material and preparation method thereof

Abstract

The invention relates to the technical field of modified polyurethane preparation, in particular to a modified rigid polyurethane foam material and a preparation method thereof.The material is specifically prepared from CO2-based polyol, polyether, deionized water, a foaming agent, a catalyst, a foam stabilizer and isocyanate. Wherein CO2-based polyol is introduced into original polyether polyol, specifically, poly (ethylene carbonate) polyol is added, so that the heat conductivity coefficient of the material can be reduced, the compression strength of the material can be improved, and the low-cost and high-performance polyurethane foam can be prepared. The finally prepared rigid polyurethane foam material has the characteristics of good heat insulation property and high pressure resistance; and the whole preparation process is simple, the whole cost is low, and the market competitiveness is high.

Description

Technical Field

[0001] This invention relates to the field of modified polyurethane preparation technology, and more specifically, to a modified polyurethane rigid foam material and its preparation method. Background Technology

[0002] Polyurethane foam, as a multifunctional polymer material, is widely used in industrial and civil fields due to its adjustable physical properties and chemical structure. Its applications can be mainly divided into three categories: rigid polyurethane foam, flexible polyurethane foam, and microporous polyurethane elastomers, each meeting the material performance requirements of different scenarios.

[0003] Rigid polyurethane foam (RPUF) is a closed-cell porous material prepared by reacting small-molecule polyols and crude MDI with foaming agents, catalysts, and surfactants. Its interior is filled with tiny, independent pores, forming a highly efficient thermal insulation barrier. Its three-dimensional cross-linked network structure endows the material with excellent dimensional stability and high mechanical properties. It is widely used in chemical pipelines, refrigerators, and cold storage insulation, and is currently the most effective thermal insulation material for cold storage. Furthermore, its lightweight and high-strength characteristics make it suitable for insulation layers in refrigerated trucks and containers in cold chain logistics, as well as for corrosion protection and insulation of oil pipelines and storage tanks.

[0004] Carbon dioxide polymer polyol is a newly developed polyurethane raw material. It is prepared by copolymerization of carbon dioxide epoxide. Its molecule contains carbonate groups and ether groups. These two groups can interact to form intramolecular and intermolecular hydrogen bonds, which have a significant impact on the physical properties of polyurethane products.

[0005] Traditional rigid polyurethane foam is prepared by reacting small-molecule, high-functionality polyethers with crude MDI. The polyethers are prepared by reacting propylene oxide (PO) with sucrose, glycerol, trimethylolpropane, etc., as initiators, under the action of catalysts. This reaction consumes a large amount of petroleum and generates a large amount of wastewater and waste residue during the production process, which requires green and high-performance technological innovation to solve the problem.

[0006] The inventor has many years of experience in the synthesis and application of CO2-based polyols. During the research process, it was discovered that polypropylene carbonate polyols obtained by copolymerizing CO2 with ethylene oxide can modify traditional rigid polyurethane foams.

[0007] Currently, there is limited research on the preparation of polyurethane foam using polyethylene carbonate polyols as raw materials, and related studies mainly focus on the preparation of flexible polyurethane foam (FPUF) and CO2-based polyols. There is no readily available technology to utilize these materials in the preparation of rigid polyurethane foams with superior performance. Summary of the Invention

[0008] In order to overcome the above-mentioned defects of the prior art, embodiments of the present invention provide a modified polyurethane rigid foam material to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A modified rigid polyurethane foam material is made from the following substances in corresponding parts by weight: comprising component A and component B.

[0011] The specific components of component A are: 1-60 parts of CO2-based polyol, 40-100 parts of polyether, 0.5-2 parts of deionized water, 5-15 parts of foaming agent, 0.5-1.5 parts of catalyst, and 0.3-3.0 parts of foam stabilizer.

[0012] Component B specifically consists of 2 to 20 parts of isocyanate.

[0013] Furthermore, the CO2-based polyol is a polyethylene carbonate polyol prepared by copolymerization of carbon dioxide and ethylene oxide, with a molecular weight of 300-1500 and a functionality of 2-6.

[0014] Furthermore, the polyether has a molecular weight of 300-800 and a functionality of 2-6.

[0015] Furthermore, the foaming agent is at least one of cyclopentane, isopentane, neopentane, n-pentane, n-butane, isobutane, cyclohexane, propane, n-hexane and its isomers, n-heptane and its isomers, alkane carbon dioxide, and methyl formate.

[0016] Furthermore, the catalyst is at least one of organotin catalysts, tertiary amine catalysts, and organobismuth catalysts.

[0017] Furthermore, the foam stabilizer is at least one of surfactant-type foam stabilizers and silicone polyether emulsion-type foam stabilizers.

[0018] Furthermore, the isocyanate has a functionality of ≥2 and an NCO content of 31-32%.

[0019] Isocyanates include any of those polyisocyanates known in the art for the manufacture of polyurethane or urethane-modified polyisocyanurate rigid foams, particularly aromatic polyisocyanates such as diphenylmethane diisocyanate provided in the form of its 2,4'-, 2,2'-, and 4,4'- isomers and mixtures thereof; mixtures of diphenylmethane diisocyanate (MDI) and its oligomers, referred to in the art as "crude" or polymeric MDI (polymethylene polyphenylene polyisocyanate), having an isocyanate functionality greater than 2; toluene diisocyanate provided in the form of its 2,4- and 2,6- isomers and mixtures thereof; 1,5-naphthylene diisocyanate; and 1,4-phenylene diisocyanate. Other organic polyisocyanates that may be mentioned include aliphatic diisocyanates such as isophorone diisocyanate, 1,6-hexane diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate.

[0020] A method for preparing a modified polyurethane rigid foam material, specifically comprising:

[0021] First, mix the CO2-based polyol and polyether according to the corresponding weight parts. Then, add deionized water, foam stabilizer, catalyst, and foaming agent in sequence. Stir at high speed until uniform, and then add isocyanate. Stir until uniform and foam.

[0022] Furthermore, the foaming temperature is controlled at 20–45°C, the stirring speed is 1000–3000 rpm, and the maturation time is 18–48 h.

[0023] The technical effects and advantages of the modified polyurethane rigid foam material of the present invention are as follows:

[0024] This invention involves a rational improvement in the formulation of raw materials. Specifically, CO2-based polyols are introduced into the original polyether polyols, specifically by adding polyethylene carbonate polyols. This reduces the thermal conductivity of the material and increases its compressive strength, resulting in the preparation of low-cost, high-performance polyurethane foam. The final rigid polyurethane foam material exhibits excellent thermal insulation and high compressive strength; furthermore, the overall preparation process is simple, the overall cost is low, and it possesses strong market competitiveness. Attached Figure Description

[0025] Figure 1 The images show SEM images of the materials corresponding to Comparative Example 1, Example 1, Example 2, and Example 3 of this invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods, and the experimental materials used in the following embodiments are all available through conventional commercial channels.

[0028] In the following examples, the unit "part" refers to weight (kg).

[0029] Example 1

[0030] Weigh out the following components according to their respective weight proportions: 20 parts polyethylene carbonate diol, 80 parts polyether 4110, 1 part deionized water, 10 parts isopentane, 1 part organotin catalyst, 2 parts silicone polyether emulsion foam stabilizer, and 10 parts isocyanate.

[0031] First, mix polyethylene carbonate diol and polyether 4110, then add deionized water, silicone polyether emulsion foam stabilizer, organotin catalyst, and isopentane foaming agent in sequence. After stirring at high speed until uniform, add isocyanate and stir until uniform foaming. During this process, control the foaming temperature at 40℃, the stirring speed at 2000 rpm, and the curing time for foaming is 24 hours.

[0032] Example 2

[0033] Weigh out the following components according to their respective weight proportions: 40 parts polyethylene carbonate diol, 60 parts polyether 4110, 1 part deionized water, 10 parts isopentane, 1 part organotin catalyst, 2 parts silicone polyether emulsion foam stabilizer, and 10 parts isocyanate.

[0034] First, mix polyethylene carbonate diol and polyether 4110, then add deionized water, silicone polyether emulsion foam stabilizer, organotin catalyst, and isopentane foaming agent in sequence. After stirring at high speed until uniform, add isocyanate and stir until uniform foaming. During this process, control the foaming temperature at 40℃, the stirring speed at 2000 rpm, and the curing time for foaming is 24 hours.

[0035] Example 3

[0036] Weigh out the following components according to their respective weight proportions: 60 parts polyethylene carbonate diol, 40 parts polyether 4110, 1 part deionized water, 10 parts isopentane, 1 part organotin catalyst, 2 parts silicone polyether emulsion foam stabilizer, and 10 parts isocyanate.

[0037] First, mix polyethylene carbonate diol and polyether 4110, then add deionized water, silicone polyether emulsion foam stabilizer, organotin catalyst, and isopentane foaming agent in sequence. After stirring at high speed until uniform, add isocyanate and stir until uniform foaming. During this process, control the foaming temperature at 40℃, the stirring speed at 2000 rpm, and the curing time for foaming is 24 hours.

[0038] Comparative Example 1

[0039] Weigh out 100 parts of polyether 4110, 1 part of deionized water, 10 parts of isopentane, 1 part of organotin catalyst, 2 parts of silicone polyether emulsion foam stabilizer, and 10 parts of isocyanate according to the corresponding weight parts.

[0040] First, stir the polyether 4110, then add deionized water, silicone polyether emulsion foam stabilizer, organotin catalyst, and isopentane foaming agent in sequence. Stir at high speed until uniform, then add isocyanate and stir until uniform foaming. During this process, control the foaming temperature at 40℃, the stirring speed during foaming at 2000rpm, and the curing time for foaming at 24h.

[0041] The only difference between Comparative Example 1 and Example 2 is that the polyethylene carbonate diol component is omitted; the other components and preparation methods are exactly the same.

[0042] The polyurethane rigid foam materials prepared in Examples 1, 2, 3, and Comparative Example 1 were tested, specifically:

[0043] (1) Observe the internal structure of the material using scanning electron microscopy;

[0044] (2) The change in thermal conductivity of the material was tested using a thermal conductivity constant temperature tester; the thermal conductivity of the foam was tested in accordance with the standard GB / T10295-2008, with the hot and cold plate temperatures set to 2℃ and 18℃.

[0045] (3) Use a tensile testing machine to test the compressive strength of the material; the foam compressive strength test shall be conducted in accordance with the standard: GB / T8813-2008.

[0046] The results of the above test (1) are attached. Figure 1 As shown, the attached Figure 1 In the figure, 'a' represents the effect of Comparative Example 1; (Attached) Figure 1 In the figure, b is the effect diagram of Example 1; Appendix Figure 1 In the figure, 'c' represents the effect diagram of Example 2; Appendix Figure 1 In the figure, d represents the effect diagram of Example 3;

[0047] Figure 1As can be seen from the SEM images, compared with Examples 1, 2 and other examples, Comparative Example 1 has more open-cell structures and a poorer internal structure. Among them, Example 3 has the best internal structure. This also verifies that within a certain range, as the CO2-based polyol increases, the open-cell phenomenon of rigid polyurethane foam gradually decreases and its performance continuously improves.

[0048] The results of the above test (2) are shown in Table 1 below. It can be seen that the thermal conductivity of all embodiments is significantly lower than that of Comparative Example 1, which is related to their internal pore structure, and the overall comprehensive properties of the materials are improved.

[0049] Table 1

[0050] Thermal conductivity (W / (m·K)) Comparative Example 1 0.0459 Example 1 0.0419 Example 2 0.0390 Example 3 0.0381

[0051] The results of the above test (3) are shown in Table 2 below. It can be seen that the compressive strength of the three embodiments is significantly improved compared with the comparative example.

[0052] Table 2

[0053] Compressive strength (kPa) Comparative Example 1 199.2 Example 1 200.8 Example 2 367.3 Example 3 252.6

[0054] As can be seen from the above, with the increase of the amount of specially added polyethylene carbonate polyol in the polyurethane material, the overall strength of the material continuously increases within a certain range, while the thermal conductivity decreases significantly, indicating that this component can significantly improve the overall performance of the material. Unlike the traditional use of polypropylene carbonate polyol, the addition of polypropylene carbonate polyol increases the thermal conductivity of rigid polyurethane foam. This invention solves the problem of high contamination in the traditional rigid foam preparation process, improves the overall performance of the material, reduces the preparation cost, and is suitable for large-scale application.

[0055] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0056] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A modified polyurethane rigid foam material, characterized in that, It is made from the following substances in corresponding parts by weight: including component A and component B, The specific components of component A are: 1-60 parts of CO2-based polyol, 40-100 parts of polyether, 0.5-2 parts of deionized water, 5-15 parts of foaming agent, 0.5-1.5 parts of catalyst, and 0.3-3.0 parts of foam stabilizer. Component B specifically consists of 2 to 20 parts of isocyanate.

2. The modified polyurethane rigid foam material according to claim 1, characterized in that, The CO2-based polyol is a polyethylene carbonate polyol prepared by copolymerization of carbon dioxide and ethylene oxide, with a molecular weight of 300-1500 and a functionality of 2-6.

3. The modified polyurethane rigid foam material according to claim 1, characterized in that, The polyether has a molecular weight of 300-800 and a functionality of 2-6.

4. The modified polyurethane rigid foam material according to claim 1, characterized in that, The foaming agent is at least one of cyclopentane, isopentane, neopentane, n-pentane, n-butane, isobutane, cyclohexane, propane, n-hexane and its isomers, n-heptane and its isomers, alkane, carbon dioxide, and methyl formate.

5. The modified polyurethane rigid foam material according to claim 1, characterized in that, The catalyst is at least one of organotin catalysts, tertiary amine catalysts, and organobismuth catalysts.

6. The modified polyurethane rigid foam material according to claim 1, characterized in that, The foam stabilizer is at least one of surfactant-type foam stabilizers and silicone polyether emulsion-type foam stabilizers.

7. The modified polyurethane rigid foam material according to claim 1, characterized in that, The isocyanate has a functionality of ≥2 and an NCO content of 31-32%.

8. A method for preparing a modified polyurethane rigid foam material as described in any one of claims 1 to 7, characterized in that, Specifically: First, mix the CO2-based polyol and polyether according to the corresponding weight parts. Then, add deionized water, foam stabilizer, catalyst, and foaming agent in sequence. Stir at high speed until uniform, and then add isocyanate. Stir until uniform and foam.

9. The method for preparing a modified polyurethane rigid foam material according to claim 8, characterized in that, The foaming temperature is controlled at 20-45℃, the stirring speed is 1000-3000 rpm, and the maturation time is 18-48 hours.

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