A water-based, rapidly expanding rigid polyurethane foam composite and its preparation method

Abstract

This invention provides an all-water-based, rapidly expanding rigid polyurethane foam compound and its preparation method. The compound is composed of component A and component B in a weight ratio of 1:1.1-1.3. Component A consists of 50-70 parts of polyether polyol A, 20 parts of polyether polyol B, 10-30 parts of polyether polyol C, 10-15 parts of flame retardant, 2 parts of emulsifier, 1.5 parts of surfactant, 8-10 parts of pure water foaming agent, 0.65 parts of catalyst, and 0.5 parts of cell opener. Polyether polyol A has a hydroxyl value of 410-470 mgKOH / g and a functionality of 5-6; polyether polyol B has a hydroxyl value of 435-465 mgKOH / g and a functionality of 4; and polyether polyol C has a hydroxyl value of 33-37 mgKOH / g and a functionality of 2-3. Component B is polymeric diphenylmethane diisocyanate, which is not only environmentally friendly and low in cost, but also has excellent foam performance, high strength, and dimensional stability.

Description

Technical Field

[0001] This invention relates to the field of rigid polyurethane technology, and in particular to an all-water-based, rapidly expanding rigid polyurethane foam compound and its preparation method. Background Technology

[0002] Polyurethane foam materials are easy to apply and have good sealing properties, making them widely used in road pothole repair. These materials are typically prepared by on-site mixing and reaction of two components: isocyanate and polyether. The choice of foaming agent directly determines the material's environmental friendliness, molding quality, and application range.

[0003] Currently, polyurethane used for road pothole repair mostly employs HCFC-141b and other chlorofluorocarbon (CFC) foaming agents. While these agents offer good foaming performance, their ODP and GWP values ​​are relatively high. In accordance with the relevant control requirements of the Montreal Protocol, they are gradually entering a phase of production restrictions and phase-out. Among existing alternative foaming agents, pentane-based agents are flammable and explosive and unsuitable for on-site construction, while HFC-based agents and LBA-based agents remain too expensive for large-scale application.

[0004] Water, as a foaming agent, has the advantages of being safe, environmentally friendly, and inexpensive. The carbon dioxide generated by its reaction with isocyanates can be used as a foaming gas source, with an ODP value of zero and a GWP value of extremely low, making it an ideal environmentally friendly approach. However, existing all-water-foamed rigid polyurethane has significant drawbacks: the reaction generates a large number of urea bonds and polyurea, resulting in high foam brittleness, insufficient strength, and poor adhesion; the concentrated exothermic reaction easily leads to core burning and yellowing; and the large shrinkage and expansion rates at high and low temperatures result in poor dimensional stability.

[0005] Furthermore, its uneven foaming, slow curing, and insufficient waterproofing and corrosion resistance make it difficult to achieve efficient and seamless repair for complex road conditions, which also seriously restricts its industrial application.

[0006] Therefore, developing a rigid polyurethane foam composite material that is all-water-based, expands rapidly, and has excellent overall performance is a problem that urgently needs to be solved in this field. Summary of the Invention

[0007] This invention provides a water-based, rapidly expanding rigid polyurethane foam composite and its preparation method, which is not only environmentally friendly and low-cost, but also has excellent foam performance, high strength, and dimensional stability.

[0008] To achieve the above objectives, in a first aspect, this application provides an all-water-based, rapidly expanding rigid polyurethane foam compound, which is composed of component A and component B mixed in a weight ratio of 1:1.1-1.3; Component A, by weight, consists of 50-70 parts polyether polyol A, 20 parts polyether polyol B, 10-30 parts polyether polyol C, 10-15 parts flame retardant, 2 parts emulsifier, 1.5 parts surfactant, 8-10 parts pure water foaming agent, 0.65 parts catalyst, and 0.5 parts cell opener. Polyether polyol A is a polyether polyol with a hydroxyl value of 410-470 mg KOH / g, a viscosity of 2500-3500 mPa·s, and a functionality of 5-6. Component B is a polyether polyol with a hydroxyl value of 435-465 mgKOH / g, a viscosity of 4000-5000 mPa.s, and a functionality of 4. Polyether polyol C is a polyether polyol with a hydroxyl value of 33-37 mgKOH / g, a viscosity of 800-1000 mPa.s, and a functionality of 2-3. Component B is a polymeric diphenylmethane diisocyanate with an NCO mass fraction of 30%~32%, and the total weight of polyether polyol A, polyether polyol B, and polyether polyol C is 100 parts.

[0009] The present invention uses only polyethers, without any polyesters. The molecular backbone is composed of ether bonds, exhibiting moderate hydrophilicity and good water miscibility and compatibility. It does not separate into layers when exposed to high levels of water. The 5-6 functional polyether polyol A forms a high-strength framework, offsetting the brittleness caused by increased urea bonds in the all-water foaming process. The 4 functional polyether polyol B possesses a self-catalyzing tertiary amine, buffering the intense exothermic reaction in high-water conditions. The 2-3 functional polyether polyol C is embedded in the network for toughening, solving the common problems of cracking and powdering in all-water foams. The resulting foam exhibits excellent performance, high strength, dimensional stability, and strong adhesion to the road substrate. The closed-cell structure effectively blocks water vapor penetration, avoiding freeze-thaw cycles and corrosion. Furthermore, with a viscosity gradient of 2500-5000 mPa·s, the system has good fluidity and can still emulsify uniformly under high water content without phase separation. This allows the use of pure water as a foaming agent. Only 8-10 parts of pure water are needed to react with MDI to generate sufficient CO2, which can stably foam to the target low density. The exothermic reaction is controllable, and the polyether structure prevents core burning and collapse. The reaction is rapid, and curing and shaping can be completed within 2 minutes, making it suitable for the needs of road emergency repair. Water is used as the only foaming agent, replacing traditional harmful fluorinated foaming agents. The raw materials are readily available and inexpensive, meeting environmental protection and Montreal Protocol requirements. It balances environmental protection and economy, and contains no physical foaming agents, alkanes, fluorinated hydrocarbons, or econicates. It is especially suitable for road pothole repair, roadbed cavity filling, and seamless road surface repair. It has zero ODP, extremely low GWP, and no flammable or explosive components, making it suitable for on-site construction on open roads. While ensuring compressive strength and adhesion, the foam molding is rapid and stable, meeting the needs of emergency road repair.

[0010] Optionally, the polyether polyol A is a sucrose polyether.

[0011] Optionally, the polyether polyol B is ethylenediamine polyether.

[0012] Optionally, the polyether polyol C is a soft, highly active polyether.

[0013] Optionally, the catalyst is N,N,N′,N″,N″-pentamethyldiethylenetriamine and N,N-dimethylcyclohexylamine, used in a weight ratio of (0.15-0.25):(0.25-0.4).

[0014] Optionally, the emulsifier is an alkylphenol polyoxyethylene ether.

[0015] Optionally, the surfactant is at least one of silicone oil 8840B and silicone oil 8415.

[0016] Optionally, the surfactant is a combination of silicone oil 8840B and silicone oil 8415, with a weight percentage of 1:0.4-0.6.

[0017] To achieve the above objectives, in a second aspect, this application provides a method for preparing an all-water-based, rapidly expanding rigid polyurethane foam composite, comprising the following steps: S1. Mix polyether polyol, flame retardant, emulsifier, surfactant, catalyst, pure water foaming agent and cell opener in a mixer, discharge and seal for storage to obtain component A; S2. Mix the components A and B at a weight ratio of 1:1.2, then inject the mixture into a mold or cavity to be filled, allow it to expand rapidly at room temperature, and complete the curing and shaping within 2 minutes to obtain a fully water-foamed rigid polyurethane foam material.

[0018] Optionally, in S1, the stirring conditions are stirring at a high speed of 800-1000 rpm for 3 minutes, and in S2, the stirring conditions are stirring at a high speed of 3000-4000 rpm for 5 seconds.

[0019] This invention provides a water-based, rapidly expanding rigid polyurethane foam compound and its preparation method. Compared with existing technologies, its advantages are as follows: It uses a blend of high-functionality, high-hydroxyl-value sucrose polyether, tetrafunctional ethylenediamine polyether, and low-functionality, low-hydroxyl-value flexible polyether, without polyester polyols. The pure ether bond structure is resistant to hydrolysis and high / low temperature freeze-thaw cycles. By controlling the number of crosslinking points through functionality and the molecular weight and reactivity through hydroxyl value, a three-dimensional network of rigid skeleton, crosslinking curing, and flexible toughening is constructed, solving the inherent defects of high brittleness, easy cracking, and low strength in water-based foaming from the molecular level. Furthermore, relying on the excellent hydrophilicity of the all-polyether and the compatibility system of the special emulsifier, it can stably support 8-10 parts of pure water as the sole foaming agent. It eliminates the need for auxiliary foaming agents such as cyclopentane, HFC, and Ecomate, avoiding problems of flammability, explosiveness, high GWP, and high cost. The reaction of water with MDI can controllably generate CO2, ensuring a stable foaming gas source and uniform cell structure. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings: Figure 1 This is a list of testing items; Figure 2 These are indentation hardness test images from Examples 1-3; Figure 3 These are indentation hardness test charts for comparison examples 1-3. Detailed Implementation

[0021] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0022] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0023] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0024] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0025] In addition, the term "multiple" should mean two or more.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] Example 1 Component A formulation (by weight) 4110 polyether polyol: 70 parts 405 polyether polyol: 20 parts 330N polyether polyol: 10 parts Flame retardant 750: 15 parts Emulsifier OP-10: 2 parts Surfactant 8440B: 1.5 parts Foaming agent H2O: 10 parts Catalyst PC-5: 0.25 parts Catalyst PC-8: 0.4 parts 0.5 parts of pore opener 501 Preparation and foaming Add the above raw materials into a container according to the ratio, stir at 800-1000 rpm for 3 minutes at room temperature, and then stir at 1500-2000 rpm for 3 minutes at high speed until the system is uniform and without layering, to obtain the composite polyether component A; mix component A and component B at a weight ratio of 1:1.2 in a high-speed mixer at 3000-4000 rpm for 5 seconds; pour the mixture into a mold, allow it to expand and fill rapidly at room temperature, and complete the curing and shaping within 2 minutes.

[0028] Example 2 Component A formulation (by weight) 4110 polyether polyol: 50 parts 405 polyether polyol: 20 parts 330N polyether polyol: 30 parts Flame retardant 750: 15 parts Emulsifier OP-10: 2 parts Surfactant 8440B: 1.5 parts Foaming agent H2O: 8 parts Catalyst PC-5: 0.25 parts Catalyst PC-8: 0.4 parts 0.5 parts of pore opener 501 Preparation and foaming Same as in Example 1, component A and component B are mixed and foamed at a weight ratio of 1:1.2.

[0029] Example 3 Component A formulation (by weight) 4110 polyether polyol: 50 parts 405 polyether polyol: 20 parts 330N polyether polyol: 30 parts Flame retardant 750: 15 parts Emulsifier OP-10: 2 parts Surfactant (compound) 815+8440B: 0.5+1 parts (total 1.5 parts) Foaming agent H2O: 7.5 parts Catalyst PC-5: 0.25 parts Catalyst PC-8: 0.4 parts 0.5 parts of pore opener 501 Preparation and foaming Same as in Example 1, component A and component B are mixed and foamed at a weight ratio of 1:1.2.

[0030] Comparative Example 1 Component A formulation (by weight) 4110 polyether polyol: 50 parts 330N polyether polyol: 50 parts Flame retardant 750: 15 parts Emulsifier OP-10: 2 parts Surfactant 815: 1.5 parts Foaming agent H2O: 12 parts Catalyst PC-5: 0.2 parts Catalyst PC-8: 0.4 parts Preparation and foaming Same as in Example 1, component A and component B are mixed and foamed at a weight ratio of 1:1.2.

[0031] Comparative Example 2 Component A formulation (by weight) 4110 polyether polyol: 40 parts 210 Polyether Polyol: 20 parts 330N polyether polyol: 40 parts Flame retardant 750: 15 parts Emulsifier OP-10: 2 parts Surfactant 815: 1.5 parts Foaming agent H2O: 12 parts Catalyst PC-5: 0.2 parts Catalyst PC-8: 0.4 parts Preparation and foaming Same as in Example 1, component A and component B are mixed and foamed at a weight ratio of 1:1.2.

[0032] Comparative Example 3 Component A formulation (by weight) 4110 polyether polyol: 80 parts 210 Polyether Polyol: 20 parts Flame retardant 750: 15 parts Emulsifier OP-10: 2 parts Surfactant 815: 1.5 parts Foaming agent H2O: 8.5 parts Catalyst PC-5: 0.2 parts Catalyst PC-8: 0.4 parts Preparation and foaming Same as in Example 1, component A and component B are mixed and foamed at a weight ratio of 1:1.2.

[0033] like Figure 1 As shown, comparing the test data of the above-described embodiments with those of the comparative processed products reveals that this invention, with all-water foaming as its core and pure water as the sole foaming medium, completely abandons traditional fluorinated foaming agents, practicing the environmentally friendly concept of zero ODP and low GWP. By precisely controlling the polyether ratio, water content, and material ratio, a gradient adaptation of foam performance is achieved, ensuring compressive strength and adhesion while enabling rapid and stable foam molding to meet the needs of emergency road repair.

[0034] Combined with appendix Figure 2 Appendix Figure 3 And the contents disclosed in Tables 1 and 2: Table 1: Table 2: A comparison of Examples 1-3 with Comparative Examples 1 and 3 shows that when only two types of polyether polyols are mixed, especially when the intermediate-functional polyether polyol B is missing, the indentation strength is much lower than that in Examples 1-3, which does not meet the requirements for road construction. In addition, a comparison of Examples 1-3 with Comparative Example 2 shows that when the amount of polyether polyol A is less than 50 parts and the amount of polyether polyol C is more than 30 parts, the indentation strength is also much lower than that in Examples 1-3, and it is also unsuitable for road repair construction.

[0035] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An all-water fast expanding rigid polyurethane foam formulation, characterized by, It is composed of a mixture of component A and component B in a weight ratio of 1:1.1-1.3; Component A, by weight, consists of 50-70 parts polyether polyol A, 20 parts polyether polyol B, 10-30 parts polyether polyol C, 10-15 parts flame retardant, 2 parts emulsifier, 1.5 parts surfactant, 8-10 parts pure water foaming agent, 0.65 parts catalyst, and 0.5 parts cell opener. Polyether polyol A is a polyether polyol with a hydroxyl value of 410-470 mg KOH / g, a viscosity of 2500-3500 mPa·s, and a functionality of 5-6. Component B is a polyether polyol with a hydroxyl value of 435-465 mgKOH / g, a viscosity of 4000-5000 mPa.s, and a functionality of 4. Polyether polyol C is a polyether polyol with a hydroxyl value of 33-37 mgKOH / g, a viscosity of 800-1000 mPa.s, and a functionality of 2-3. Component B is a polymeric diphenylmethane diisocyanate with an NCO mass fraction of 30%~32%, and the total weight of polyether polyol A, polyether polyol B, and polyether polyol C is 100 parts.

2. A total water blowing fast expanding rigid polyurethane foam formulation as claimed in claim 1, wherein: The polyether polyol A is a sucrose polyether.

3. The all-water-based, rapidly expanding rigid polyurethane foam composite material as described in claim 2, characterized in that: The polyether polyol B is ethylenediamine polyether.

4. The all-water-based, rapidly expanding rigid polyurethane foam composite material as described in claim 3, characterized in that, The polyether polyol C is a soft, highly active polyether.

5. The all-water-based, rapidly expanding rigid polyurethane foam composite material as described in claim 1, characterized in that: The catalyst is N,N,N′,N″,N″-pentamethyldiethylenetriamine and N,N-dimethylcyclohexylamine, used in a weight ratio of (0.15-0.25):(0.25-0.4).

6. The all-water-based, rapidly expanding rigid polyurethane foam composite material as described in claim 1, characterized in that: The emulsifier is alkylphenol polyoxyethylene ether.

7. The all-water-based, rapidly expanding rigid polyurethane foam composite material as described in claim 1, characterized in that: The surfactant is at least one of silicone oil 8840B and silicone oil 8415.

8. The all-water-based, rapidly expanding rigid polyurethane foam composite material as described in claim 7, characterized in that: The surfactant is a combination of two silicone oils, 8840B and 8415, with a weight percentage of 1:0.4-0.

6.

9. A method for preparing a water-based, rapidly expanding rigid polyurethane foam composite, characterized in that: Includes the following steps: S1. Mix polyether polyol, flame retardant, emulsifier, surfactant, catalyst, pure water foaming agent and cell opener in a mixer, discharge and seal for storage to obtain component A; S2. Mix and stir the components A and B at a weight ratio of 1:1.2, then inject the mixture into the mold or the cavity to be filled, and allow it to expand and fill rapidly at room temperature. The curing and shaping are completed within 2 minutes to obtain a fully water-foamed rigid polyurethane foam material.

10. The method for preparing a water-based, rapidly expanding rigid polyurethane foam composite as described in claim 9, characterized in that: In S1, the stirring conditions are stirring at a high speed of 800-1000 rpm for 3 minutes, and in S2, the stirring conditions are stirring at a high speed of 3000-4000 rpm for 5 seconds.

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