Low-odor high-resilience polyurethane foam and method of making same

Abstract

The present disclosure discloses a low-odor high-resilience polyurethane foam and a preparation method thereof, and relates to the field of foam preparation. The low-odor high-resilience polyurethane foam comprises a polyol side composition and an isocyanate component. The polyol side composition comprises, based on 100 parts by mass of the polyether polyol in the polyol side composition: 2-5 parts by mass of open-cell polyether, 1-2 parts by mass of diethanolamine, 0.2-0.5 parts by mass of low-odor low-cyclic polyether modified silicone oil, 0.3-0.5 parts by mass of a reactive composite catalyst, 0.3-0.7 parts by mass of a low-odor gel catalyst, and 2.5-3.8 parts by mass of water. The isocyanate component is diphenylmethane diisocyanate. The ratio of the isocyanate component to the polyol side composition is 100-120 in terms of the isocyanate index. The present disclosure improves the problems of foam odor, high volatile organic compound emission, insufficient long-term odor retention, difficulty in balancing high resilience and low compression permanent set, and limited foam structure regulation means.

Description

Technical Field

[0001] This disclosure relates to the field of foam preparation, and in particular to a low-odor, high-resilience polyurethane foam and its preparation method. Background Technology

[0002] Polyurethane flexible foam has been widely used in interior components such as car seats, headrests, and armrests due to its adjustable density, ease of design in terms of resilience and compression stiffness. In existing technologies, to achieve low odor and high resilience, a method has been proposed to prepare foam for passenger car seats by using compositions of low-odor polyether polyols, grafted polyethers, and low-toxicity isocyanates.

[0003] Chinese invention patent application number 201310222700.0 discloses a low-odor, high-resilience sponge for bus seats and its preparation method. In this application, the composite material consists of 50-80 parts of polyether polyol, 20-50 parts of grafted polyether, 0.2-0.3 parts of amine catalyst, 0.2-0.5 parts of pre-gel catalyst, 0.5-0.7 parts of post-gel catalyst, 3-4 parts of foaming agent, 1 part of crosslinking agent, and 0.5-0.7 parts of stabilizer. The black component is a polyether-modified MDI system, with a standard odor level of 3.0 (VDA 270) and a TVOC of 13.9 μgC / g (VDA 270). (277) To a certain extent, it achieves a combination of low odor and high resilience; however, this application also has problems such as high foam odor and volatile organic compound emissions, insufficient long-term odor retention, difficulty in achieving both high resilience and low compression set, limited means of controlling cell structure, and insufficient process stability and flame retardant compatibility of the low odor system; specifically, the catalytic system of this application uses non-reactive or limitedly reactive amine catalysts, and the small molecule amines and their byproducts remaining after foaming continue to volatilize and migrate, resulting in high foam odor and volatile organic compound emissions, and insufficient long-term odor retention; cell control relies on conventional silicone oil and... The empirical formulation of branched polyethers lacks precise control over open-cell ratio and pore size distribution. Furthermore, increasing crosslinking density in pursuit of high resilience increases compression set, making it difficult to achieve both high resilience and low compression set, and limiting the means of controlling cell structure. When improving the low-odor content, the components such as low-odor, high-activity polyether, reactive catalytic system, and low-odor, open-cell silicone oil were not systematically and synergistically designed. After formula adjustment, the reaction kinetics and phase separation behavior changed, resulting in a narrowing of the foaming process window, increased product quality fluctuations, and reduced compatibility and synergistic effect between the matrix and the flame retardant system, leading to insufficient process stability and flame retardant compatibility of the low-odor system.

[0004] Therefore, a low-odor, high-resilience polyurethane foam and its preparation method are proposed to address the problems of high odor and volatile organic compound emissions, insufficient long-term odor retention, difficulty in achieving both high resilience and low compression set, limited means of controlling cell structure, and insufficient process stability and flame retardant compatibility of the low-odor system. Summary of the Invention

[0005] The purpose of this disclosure is to provide a low-odor, high-resilience polyurethane foam and its preparation method, which solves the problems of high odor and volatile organic compound emissions, insufficient long-term odor retention, difficulty in achieving both high resilience and low compression set, limited means of controlling cell structure, and insufficient process stability and flame retardant compatibility of the low-odor system.

[0006] To achieve this objective, the present disclosure adopts the following technical solution: A low-odor, high-resilience polyurethane foam, the low-odor, high-resilience polyurethane foam comprising a polyol side composition and an isocyanate component; Based on 100 parts by weight of the polyether polyol in the polyol-side composition, the polyol-side composition comprises: 2-5 parts by weight of open-cell polyether, 1-2 parts by weight of diethanolamine, 0.2-0.5 parts by weight of low-odor, low-cyclic polyether modified silicone oil, 0.3-0.5 parts by weight of reactive composite catalyst, 0.3-0.7 parts by weight of low-odor gel catalyst, and 2.5-3.8 parts by weight of water; The isocyanate component is diphenylmethane diisocyanate, and the ratio of the isocyanate component to the polyol side composition is 100-120 based on the isocyanate index.

[0007] Based on 100 parts by weight of the polyether polyol, the polyol-side composition comprises: 2.5–3.5 parts by weight of open-cell polyether, 1.2–1.8 parts by weight of diethanolamine, 0.25–0.4 parts by weight of low-odor, low-cyclic polyether modified silicone oil, 0.35–0.45 parts by weight of reactive composite catalyst, 0.4–0.6 parts by weight of low-odor gel catalyst, and 2.8–3.5 parts by weight of water; The ratio of the isocyanate component to the polyol side composition is 105 to 115, calculated by the isocyanate index.

[0008] The polyol-side composition also includes 0.5 to 2 parts by weight of environmentally friendly polyether color paste; the environmentally friendly polyether color paste is a low-VOC color paste with polyether as a carrier; the water is deionized water or softened water.

[0009] The reactive composite catalyst comprises a reactive foaming catalytic component and a reactive auxiliary gel catalytic component, wherein the mass ratio of the reactive foaming catalytic component to the reactive auxiliary gel catalytic component is 4:6 to 6:4.

[0010] The reactive foaming catalyst component includes a dihydroxyethyl ethylenediamine-based reactive tertiary amine catalyst; the low-odor gel catalyst is a bismuth-based gel catalyst, which includes bismuth isooctanoate. The low-odor, low-cyclic polyether modified silicone oil is either a low-odor closed-cell polyether modified silicone oil or a low-odor cell-stabilized polyether modified silicone oil.

[0011] A method for preparing low-odor, high-resilience polyurethane foam, wherein the method is applied to the aforementioned low-odor, high-resilience polyurethane foam, and the method comprises the following steps: Step S1: Prepare a polyol-side composition and mix it with an isocyanate component to obtain a liquid reactant. Step S2: The liquid reactive material is foamed, cured, and demolded to obtain a foam product; Step S3: Perform post-curing and aging treatment on the foam product to obtain low-odor, high-resilience polyurethane foam.

[0012] The polyol-side composition in step S1 is obtained according to the following steps: Polyether polyols are added to a premixing device for premixing to obtain premixed polyethers; then, open-cell polyethers, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, reactive composite catalysts and low-odor gel catalysts are added to the premixed polyethers, and the mixture is stirred and dispersed to obtain a polyol mixture; subsequently, water is added to the polyol mixture and dispersed and mixed, and vacuum degassing is performed to obtain a polyol side composition. The premixing temperature is 40–60℃, the stirring speed is 300–800 r / min, and the time is 5–15 min; the stirring and dispersing speed is 500–1000 r / min, and the time is 10–20 min; the gauge pressure of the vacuum degassing treatment is -0.09 MPa to -0.06 MPa, and the time is 5–15 min.

[0013] The liquid reactant in step S1 is obtained according to the following steps: The polyol side composition and the isocyanate component are delivered to the mixing head via a metering pump and sheared and mixed in the mixing head for 1 to 3 seconds to obtain the liquid reactive material.

[0014] The foam product in step S2 is obtained according to the following steps: Liquid reactive materials are injected into the mold cavity to carry out foaming and gelation reactions to obtain foam; the foam is then kept in the mold to continue curing, and after curing, it is demolded to obtain the foam product; The mold cavity temperature is 45–65℃, the foaming reaction time is 20–60s, the gelation reaction time is 40–90s, and the residence time in the mold is 150–300s.

[0015] The low-odor, high-resilience polyurethane foam in step S3 is obtained according to the following steps: The demolded foam product is placed in a hot air circulation environment at 40-60℃ for 4-12 hours to obtain a pre-finished product; then the pre-finished product is placed in an environment at 20-30℃ for 24-72 hours to obtain low-odor, high-resilience polyurethane foam.

[0016] Compared with the prior art, this disclosure has the following beneficial effects: This disclosure provides a low-odor, high-resilience polyurethane foam and its preparation method. The foam utilizes a combination of open-cell polyether, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, a reactive composite catalyst, a low-odor gel catalyst, water, and an isocyanate index of 100-120. This combination allows the components to work synergistically, ensuring high resilience while reducing compression set and improving the uniformity and stability of the cell structure. Furthermore, under conditions of comparable apparent density and consistent flame retardant system, this foam exhibits higher resilience, lower compression set, and lower initial pressure compared to existing foams. The study examined the initial odor level, odor level after aging, and TVOC levels, demonstrating that the synergistic control of open-cell polyether, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, reactive composite catalyst, low-odor gel catalyst, water, and isocyanate index can reduce the residual small molecules and volatile organic compound release in foam, improve the low-odor performance and long-term odor stability of foam, and simultaneously achieve high resilience, low compression set, and a better cell structure. This addresses the problems of high foam odor and volatile organic compound emissions, insufficient long-term odor retention, difficulty in balancing high resilience and low compression set, and limited means of controlling cell structure. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0018] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which this disclosure can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this disclosure can produce, should still fall within the scope of the technical content disclosed herein.

[0019] Figure 1 This is a flowchart of the preparation method in the embodiments of this disclosure. Detailed Implementation

[0020] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art.

[0021] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0022] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0023] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0024] Please see Figure 1 This disclosure provides a low-odor, high-resilience polyurethane foam, which includes a polyol-side composition and an isocyanate component; wherein the polyol-side composition includes a polyether polyol, an open-cell polyether, diethanolamine, a low-odor, low-cyclic polyether modified silicone oil, a reactive composite catalyst, a low-odor gel catalyst, and water.

[0025] The preferred polyether polyol is a low-odor, high-activity polyether polyol. Using a low-odor, high-activity polyether polyol as the main soft segment raw material for foam helps reduce the odor and volatile organic compound release from the raw material itself, while ensuring sufficient reaction with the isocyanate component to form a stable polyurethane network structure.

[0026] Based on 100 parts by weight of polyether polyol, the amount of open-cell polyether used is 2 to 5 parts by weight, preferably 2.5 to 3.5 parts by weight. Open-cell polyether is used to adjust the cell wall strength and cell rupture behavior, so that the foam forms a suitable open-cell structure, thereby improving the air permeability, resilience and feel of the foam.

[0027] The amount of diethanolamine used is 1 to 2 parts by weight, preferably 1.2 to 1.8 parts by weight. Diethanolamine participates in the polyurethane reaction as a crosslinking or chain extender component, which can adjust the crosslinking density and hard segment content of the foam, thereby improving the resilience of the foam and reducing compression set.

[0028] The amount of low-odor, low-cyclic polyether modified silicone oil used is 0.2 to 0.5 parts by weight, preferably 0.25 to 0.4 parts by weight. The low-odor, low-cyclic polyether modified silicone oil can be a low-odor closed-cell polyether modified silicone oil or a low-odor cell-stabilizing polyether modified silicone oil. It is used to reduce the interfacial tension of the foaming system, stabilize the cell structure, and reduce defects such as cell coalescence and collapse.

[0029] The reactive composite catalyst is used in an amount of 0.3–0.5 parts by mass, preferably 0.35–0.45 parts by mass. The reactive composite catalyst includes a reactive foaming catalytic component and a reactive auxiliary gel catalytic component. The reactive auxiliary gel catalytic component is a reactive tertiary amine gel catalyst containing active hydrogen groups, which can participate in polyurethane network formation while catalyzing the gel reaction. The mass ratio of the reactive foaming catalytic component to the reactive auxiliary gel catalytic component is 4:6–6:4, preferably 1:1. The reactive foaming catalytic component includes a dihydroxyethylethylenediamine reactive tertiary amine catalyst. This type of catalyst can regulate the foaming reaction rate between water and isocyanate, while also considering the gel reaction rate between polyol and isocyanate, thus matching cell growth and polymer network formation.

[0030] The amount of the low-odor gel catalyst is 0.3 to 0.7 parts by weight, preferably 0.4 to 0.6 parts by weight. The low-odor gel catalyst is a bismuth-based gel catalyst, including bismuth isooctanoate. This low-odor gel catalyst is used to promote the formation of polyurethane networks and improve the support and dimensional stability of the foam during the foaming process.

[0031] The amount of water used is 2.5–3.8 parts by weight, preferably 2.8–3.5 parts by weight. The water is deionized water or softened water. Water acts as a chemical foaming agent, reacting with the isocyanate component to generate carbon dioxide gas, thereby forming a cell structure. By controlling the amount of water used, the foam density, cell size, and cell uniformity can be adjusted.

[0032] The polyol-side composition also includes environmentally friendly polyether color paste, used in amounts of 0.5 to 2 parts by weight. The environmentally friendly polyether color paste is a low-VOC color paste with polyether as a carrier. It has good compatibility with the polyether polyol system and is used to meet the appearance and color requirements of foam products while reducing the adverse effects of the color paste on foam odor and VOC release.

[0033] The isocyanate component is a diphenylmethane diisocyanate isocyanate, and the ratio of the isocyanate component to the polyol side composition, calculated by the isocyanate index, is 100-120, preferably 105-115. By controlling the isocyanate index, the crosslinking density, hard segment content, and microphase structure of the foam can be adjusted, thereby enabling the foam to maintain high resilience while having low compression set.

[0034] In this disclosure, the polyether polyol, open-cell polyether, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, reactive composite catalyst, reactive foaming catalyst component, reactive auxiliary gelation catalyst component, low-odor gelation catalyst, environmentally friendly polyether color paste, and isocyanate component can all be conventional commercially available products in the field. The specific models and suppliers are not limited, as long as they can achieve the technical effects described in this disclosure. Moreover, each component can be obtained through existing industrial channels and is applicable to existing molding foaming processes and continuous foaming processes, thus having good industrial application value.

[0035] This disclosure also proposes a method for preparing low-odor, high-resilience polyurethane foam. This method is applied to the aforementioned low-odor, high-resilience polyurethane foam, such as... Figure 1 As shown, the preparation method includes the following steps: Step S1: Prepare a polyol-side composition and mix it with an isocyanate component to obtain a liquid reactant. The polyol-side composition in step S1 is obtained according to the following steps: Polyether polyols are added to a premixing device for premixing to obtain premixed polyethers; then, open-cell polyethers, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, reactive composite catalysts and low-odor gel catalysts are added to the premixed polyethers, and the mixture is stirred and dispersed to obtain a polyol mixture; subsequently, water is added to the polyol mixture and dispersed and mixed, and vacuum degassing is performed to obtain a polyol side composition. The premixing temperature is 40–60℃, the stirring speed is 300–800 r / min, and the time is 5–15 min; the stirring and dispersing speed is 500–1000 r / min, and the time is 10–20 min; the gauge pressure of the vacuum degassing treatment is -0.09 MPa to -0.06 MPa, and the time is 5–15 min.

[0036] The liquid reactants in step S1 are obtained according to the following steps: The polyol side composition and the isocyanate component are delivered to the mixing head via a metering pump and sheared and mixed in the mixing head for 1 to 3 seconds to obtain liquid reactive materials.

[0037] Step S2: The liquid reactive material is foamed, cured, and demolded to obtain foam products; The foam product in step S2 is obtained according to the following steps: Liquid reactive materials are injected into the mold cavity to carry out foaming and gelation reactions to obtain foam; the foam is then kept in the mold to continue to solidify, and after solidification, it is demolded to obtain foam products; The mold cavity temperature is 45–65℃, the foaming reaction time is 20–60s, the gelation reaction time is 40–90s, and the residence time in the mold is 150–300s.

[0038] In another method, the liquid reactant can also be formed by continuous block foaming, in which the polyol side composition and isocyanate component are separately conveyed to the pouring head and continuously poured on the conveyor belt to form a foam, followed by preliminary solidification, cutting and curing.

[0039] Step S3: Post-curing and aging treatment of the foam product to obtain low-odor, high-resilience polyurethane foam.

[0040] The low-odor, high-resilience polyurethane foam in step S3 is obtained according to the following steps: The demolded foam product is placed in a hot air circulation environment at 40-60℃ for 4-12 hours to obtain a pre-finished product; then the pre-finished product is placed in an environment at 20-30℃ for 24-72 hours to obtain low-odor, high-resilience polyurethane foam.

[0041] In summary, the low-odor, high-resilience polyurethane foam disclosed herein achieves high resilience performance while maintaining low compression set, low odor level, and low volatile organic compound release through the synergistic combination of low-odor, high-activity polyether, reactive composite catalyst, low-odor gel catalyst, low-odor, low-cyclic polyether modified silicone oil, open-cell polyether, and isocyanate index, thus possessing good industrial application value.

[0042] Example 1: This embodiment provides a low-odor, high-resilience polyurethane foam. Based on 100 parts by weight of polyether polyol, the polyol-side composition includes 100 parts by weight of low-odor, high-activity polyether polyol, 3.0 parts by weight of open-cell polyether, 1.5 parts by weight of diethanolamine, 0.3 parts by weight of low-odor, low-cyclic polyether modified silicone oil, 0.4 parts by weight of reactive composite catalyst, 0.5 parts by weight of low-odor gel catalyst, 3.0 parts by weight of water, and 1.0 part by weight of environmentally friendly polyether color paste.

[0043] The reactive composite catalyst includes a reactive foaming catalytic component and a reactive auxiliary gel catalytic component, with a mass ratio of 1:1. The reactive foaming catalytic component includes a dihydroxyethyl ethylenediamine reactive tertiary amine catalyst. The low-odor gel catalyst is bismuth isooctanoate. The low-odor, low-cyclic polyether modified silicone oil is a low-odor, closed-cell polyether modified silicone oil. The water is deionized water.

[0044] The isocyanate component is a diphenylmethane diisocyanate, and the amount added is calculated according to the isocyanate index of 110.

[0045] The preparation method of low-odor, high-resilience polyurethane foam in this embodiment specifically includes the following steps: Low-odor, high-activity polyether polyol was added to a premixing tank and premixed at 50°C with a stirring speed of 600 r / min for 10 min to obtain premixed polyether.

[0046] Open-cell polyether, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, environmentally friendly polyether color paste, reactive composite catalyst and low-odor gel catalyst were added sequentially to the premixed polyether and dispersed at a stirring speed of 800 r / min for 15 min to obtain a polyol mixture.

[0047] Deionized water was added to the polyol mixture, and the mixture was dispersed and mixed at 25°C for 8 min. Then, the mixture was degassed under vacuum at a gauge pressure of -0.08 MPa for 10 min to obtain the polyol side composition.

[0048] The polyol side composition and isocyanate component are controlled at 25°C and delivered to the mixing head through a metering pump. They are sheared and mixed in the mixing head for 2 seconds to obtain liquid reaction material.

[0049] Liquid reactive materials are injected into a preheated mold cavity at 55°C. The liquid reactive materials undergo foaming and gelation reactions within the mold; the foaming reaction takes 35 seconds, the gelation reaction takes 65 seconds, and the residence time within the mold is 210 seconds. After curing, the material is demolded to obtain the foamed product.

[0050] The demolded foam product is kept in a 50℃ hot air circulation environment for 8 hours to obtain a pre-finished product; then the pre-finished product is placed in a 25℃ environment for 24 hours to obtain low-odor, high-resilience polyurethane foam.

[0051] Example 2: The basic content is the same as in Example 1, except that: This embodiment provides a low-odor, high-resilience polyurethane foam. Based on 100 parts by weight of polyether polyol, the polyol-side composition includes 100 parts by weight of low-odor, high-activity polyether polyol, 2.5 parts by weight of open-cell polyether, 1.2 parts by weight of diethanolamine, 0.25 parts by weight of low-odor, low-cyclic polyether modified silicone oil, 0.35 parts by weight of reactive composite catalyst, 0.4 parts by weight of low-odor gel catalyst, 2.8 parts by weight of water, and 0.8 parts by weight of environmentally friendly polyether color paste.

[0052] The isocyanate component is a diphenylmethane diisocyanate, and the amount added is calculated according to the isocyanate index of 105.

[0053] In the corresponding preparation method of low-odor, high-resilience polyurethane foam, the premixing temperature of polyether polyol is 45℃, the premixing speed is 500r / min, and the premixing time is 12min; the stirring and dispersion speed after the addition of additives and catalyst is 700r / min, and the stirring and dispersion time is 15min; the gauge pressure of vacuum degassing treatment is -0.07MPa, and the time is 12min; the mixing head shearing time is 2s; the mold cavity temperature is 50℃; the residence time in the mold is 240s; the hot air curing temperature is 45℃, and the heat preservation time is 10h; the room temperature aging time is 48h.

[0054] Example 3: The basic content is the same as in Example 1, except that: This embodiment provides a low-odor, high-resilience polyurethane foam. Based on 100 parts by weight of polyether polyol, the polyol-side composition includes 100 parts by weight of low-odor, high-activity polyether polyol, 3.5 parts by weight of open-cell polyether, 1.8 parts by weight of diethanolamine, 0.4 parts by weight of low-odor, low-cyclic polyether modified silicone oil, 0.45 parts by weight of reactive composite catalyst, 0.6 parts by weight of low-odor gel catalyst, 3.5 parts by weight of water, and 1.5 parts by weight of environmentally friendly polyether color paste.

[0055] The isocyanate component uses diphenylmethane diisocyanate isocyanate, and the amount added is calculated according to the isocyanate index of 115.

[0056] In the corresponding preparation method of low-odor, high-resilience polyurethane foam, the premixing temperature of polyether polyol is 55℃, the premixing speed is 700 r / min, and the premixing time is 8 min; the stirring and dispersion speed after the addition of additives and catalyst is 900 r / min, and the stirring and dispersion time is 12 min; the gauge pressure of vacuum degassing treatment is -0.085 MPa, and the time is 8 min; the mixing head shearing mixing time is 3 s; the mold cavity temperature is 60℃; the residence time in the mold is 180 s; the hot air curing temperature is 55℃, and the heat preservation time is 6 h; the room temperature aging time is 36 h.

[0057] Comparative Example 1: The basic content is the same as in Example 1, except that: Comparative Example 1 provides a high-resilience polyurethane foam that does not use low-odor, low-cyclic polyether modified silicone oil, reactive composite catalyst, and low-odor gel catalyst, but instead uses silicone oil, amine catalyst, and organometallic catalyst.

[0058] Based on 100 parts by weight of high-resilience polyether polyol, the composition includes 0.8 parts by weight of silicone oil, 0.25 parts by weight of amine catalyst, 0.18 parts by weight of organometallic catalyst, 1.5 parts by weight of diethanolamine, 3.0 parts by weight of water, and 1.0 parts by weight of color paste.

[0059] The isocyanate component is a diphenylmethane diisocyanate, and the amount added is calculated according to the isocyanate index of 110.

[0060] The following is a comparison of various data between the low-odor, high-resilience polyurethane foam and the high-resilience polyurethane foam in Example 1. Please refer to Table 1 for details: Table 1 As shown in Table 1, under the conditions of basically equivalent apparent density and consistent flame retardant system, the foam obtained in Example 1 has a higher resilience and lower compression set compared to Comparative Example 1. This indicates that the present disclosure can improve the resilience and compression recovery performance of foam through the synergistic control of open-cell polyether, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, reactive composite catalyst, low-odor gel catalyst, water, and isocyanate index.

[0061] Meanwhile, the initial odor level, odor level after aging, and TVOC of the foam obtained in Example 1 were all lower than those in Comparative Example 1, indicating that the low-odor raw material system and the catalytic system composed of reactive composite catalyst and low-odor gel catalyst used in this disclosure help reduce the residue of small molecules and the release of volatile organic compounds in the foam, thereby improving the low-odor performance and long-term odor stability of the foam.

[0062] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0063] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A low-odor, high-resilience polyurethane foam, characterized in that, The low-odor, high-resilience polyurethane foam comprises a polyol side composition and an isocyanate component; Based on 100 parts by weight of the polyether polyol in the polyol-side composition, the polyol-side composition comprises: 2-5 parts by weight of open-cell polyether, 1-2 parts by weight of diethanolamine, 0.2-0.5 parts by weight of low-odor, low-cyclic polyether modified silicone oil, 0.3-0.5 parts by weight of reactive composite catalyst, 0.3-0.7 parts by weight of low-odor gel catalyst, and 2.5-3.8 parts by weight of water; The isocyanate component is diphenylmethane diisocyanate, and the ratio of the isocyanate component to the polyol side composition is 100-120 based on the isocyanate index.

2. The low-odor, high-resilience polyurethane foam according to claim 1, characterized in that, Based on 100 parts by weight of the polyether polyol, the polyol-side composition comprises: 2.5–3.5 parts by weight of open-cell polyether, 1.2–1.8 parts by weight of diethanolamine, 0.25–0.4 parts by weight of low-odor, low-cyclic polyether modified silicone oil, 0.35–0.45 parts by weight of reactive composite catalyst, 0.4–0.6 parts by weight of low-odor gel catalyst, and 2.8–3.5 parts by weight of water; The ratio of the isocyanate component to the polyol side composition is 105 to 115, calculated by the isocyanate index.

3. The low-odor, high-resilience polyurethane foam according to claim 1, characterized in that, The polyol-side composition also includes 0.5 to 2 parts by weight of environmentally friendly polyether color paste; the environmentally friendly polyether color paste is a low-VOC color paste with polyether as a carrier; the water is deionized water or softened water.

4. The low-odor, high-resilience polyurethane foam according to claim 1, characterized in that, The reactive composite catalyst comprises a reactive foaming catalytic component and a reactive auxiliary gel catalytic component, wherein the mass ratio of the reactive foaming catalytic component to the reactive auxiliary gel catalytic component is 4:6 to 6:

4.

5. The low-odor, high-resilience polyurethane foam according to claim 4, characterized in that, The reactive foaming catalyst component includes a dihydroxyethyl ethylenediamine-based reactive tertiary amine catalyst; the low-odor gel catalyst is a bismuth-based gel catalyst, which includes bismuth isooctanoate. The low-odor, low-cyclic polyether modified silicone oil is either a low-odor closed-cell polyether modified silicone oil or a low-odor cell-stabilized polyether modified silicone oil.

6. A method for preparing low-odor, high-resilience polyurethane foam, characterized in that, The preparation method is applied to the low-odor, high-resilience polyurethane foam according to any one of claims 1 to 5, and the preparation method includes the following steps: Step S1: Prepare a polyol-side composition and mix it with an isocyanate component to obtain a liquid reactant. Step S2: The liquid reactive material is foamed, cured, and demolded to obtain a foam product; Step S3: Perform post-curing and aging treatment on the foam product to obtain low-odor, high-resilience polyurethane foam.

7. The method for preparing low-odor, high-resilience polyurethane foam according to claim 6, characterized in that, The polyol-side composition in step S1 is obtained according to the following steps: Polyether polyols are added to a premixing device for premixing to obtain premixed polyethers; then, open-cell polyethers, diethanolamine, low-odor, low-cyclic polyether modified silicone oil, reactive composite catalysts and low-odor gel catalysts are added to the premixed polyethers, and the mixture is stirred and dispersed to obtain a polyol mixture; subsequently, water is added to the polyol mixture and dispersed and mixed, and vacuum degassing is performed to obtain a polyol side composition. The premixing temperature is 40–60℃, the stirring speed is 300–800 r / min, and the time is 5–15 min; the stirring and dispersing speed is 500–1000 r / min, and the time is 10–20 min; the gauge pressure of the vacuum degassing treatment is -0.09 MPa to -0.06 MPa, and the time is 5–15 min.

8. The method for preparing low-odor, high-resilience polyurethane foam according to claim 6, characterized in that, The liquid reactant in step S1 is obtained according to the following steps: The polyol side composition and the isocyanate component are delivered to the mixing head via a metering pump and sheared and mixed in the mixing head for 1 to 3 seconds to obtain the liquid reactive material.

9. The method for preparing low-odor, high-resilience polyurethane foam according to claim 6, characterized in that, The foam product in step S2 is obtained according to the following steps: Liquid reactive materials are injected into the mold cavity to carry out foaming and gelation reactions to obtain foam; the foam is then kept in the mold to continue curing, and after curing, it is demolded to obtain the foam product; The mold cavity temperature is 45–65℃, the foaming reaction time is 20–60s, the gelation reaction time is 40–90s, and the residence time in the mold is 150–300s.

10. The method for preparing low-odor, high-resilience polyurethane foam according to claim 6, characterized in that, The low-odor, high-resilience polyurethane foam in step S3 is obtained according to the following steps: The demolded foam product is placed in a hot air circulation environment at 40-60℃ for 4-12 hours to obtain a pre-finished product; then the pre-finished product is placed in an environment at 20-30℃ for 24-72 hours to obtain low-odor, high-resilience polyurethane foam.

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