An antioxidant foaming material and its preparation method

Abstract

This invention discloses an antioxidant foaming material and its preparation method. The material is formed by mixing and reacting component A and component B in a weight ratio of 100:30-50. Component A includes the following raw materials in parts by weight: 90-100 parts of a basic polyether composition, 1-4 parts of water, 0.5-2 parts of an organosilicon surfactant, 0.3-1.5 parts of a complex amine catalyst, and 0.5-2 parts of a complex antioxidant. The basic polyether composition is a compound of white oil polyether polyol and trifunctional polyether polyol. Component B is toluene diisocyanate, which is a mixture of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate. This invention uses a metal-free complex amine catalyst, completely free of metal components such as tin, bismuth, and zinc, which avoids the catalytic acceleration effect of metal ions on the oxidative degradation reaction, significantly delays the thermo-oxidative decomposition and mechanical decay of polyurethane segments, and improves the environmental friendliness of the material, meeting the requirements for low-toxicity and low-residue use in home and automotive interiors.

Description

Technical Field

[0001] This invention belongs to the field of foaming material technology, and specifically relates to an antioxidant foaming material and its preparation method. Background Technology

[0002] Polyurethane flexible foam, with its excellent resilience, comfort, cushioning, and moldability, has become a core functional material in home furnishings such as pillow cores, mattresses, cushions, backrests, as well as automotive seats, headrests, and armrests. Especially in home sleep settings, mattresses and pillow cores are in direct contact with the human body and are subjected to long-term temperature and humidity changes, sweat evaporation, air oxidation, and continuous stress, placing extremely high demands on the material's aging resistance, yellowing resistance, dimensional stability, and lifespan. Meanwhile, extended applications such as automotive interiors also face complex aging factors such as sunlight, high temperatures, and nitrogen oxides, further driving the industry's demand for highly durable, highly stable, and environmentally friendly foam materials. Traditional polyurethane flexible foams, to meet the requirements of support strength and manufacturing processes, generally adopt a composite system of polyether polyols and polymer polyols, relying on metal catalysis systems and multi-component isocyanates to achieve rapid curing. However, these systems are prone to problems such as thermo-oxidative aging, humid heat yellowing, resilience decline, and increased compression set during long-term use. This not only affects the consistency of appearance but also reduces user comfort and safety, making it difficult to meet the long-term stability requirements of high-end home furnishings and automotive interiors. With the popularization of green manufacturing and healthy home concepts, heavy metal-free, low-volatile, aging-resistant, and yellowing-resistant materials have become key directions for industry technological upgrades. Developing high-performance antioxidant foaming materials suitable for home scenarios such as pillow cores and mattresses, while also meeting the requirements of automotive interiors, has become an important issue that urgently needs to be addressed in this field.

[0003] Existing polyurethane flexible foam technologies primarily focus on density optimization, cost control, reducing volatile organic compounds (VOCs), and improving molding stability. Some solutions achieve low density, low odor, and low formaldehyde release through catalyst blending and raw material ratio adjustments, finding some application in conventional furniture and ordinary cushion products. However, most existing technologies fail to systematically address the core issues of easy oxidation, yellowing, and degradation at the molecular structure and aging mechanism levels. Most formulations still use polymer polyols and toluene diisocyanate and diphenylmethane diisocyanate blends, lacking targeted long-lasting antioxidant components. The unsaturated grafted segments in polymer polyols contain numerous easily oxidized sites, readily triggering free radical chain reactions under heat and long-term stress. The diphenylmethane diisocyanate structure easily generates quinone chromophores under light, humidity, and nitrogen oxides, leading to significant yellowing. Residual metal ions significantly catalyze oxidative degradation, accelerating the breakage of internal chemical bonds, causing changes in hardness, decreased resilience, and increased compression set. For home furnishing products such as mattresses and pillows that are subjected to constant pressure and temperature and humidity changes over a long period of time, the aforementioned defects will directly lead to problems such as sagging, deformation, yellowing, and powdering within the product's lifespan. This not only reduces the user experience but also shortens the actual lifespan of the product, failing to meet the comprehensive requirements of high-end home furnishings for durability, aesthetics, and health and safety.

[0004] Faced with the increasingly urgent demand for high-weather-resistant, anti-aging, and anti-yellowing polyurethane flexible foam in home sleep and automotive interior scenarios, the industry urgently needs a new type of foaming material that can overcome the shortcomings of traditional formulas and fundamentally improve antioxidant and aging-resistant properties. While existing technologies have made some improvements in lightweighting and low VOCs, a complete technical solution has not yet been formed, with home pillows and mattresses as the main application scenarios and long-term resistance to thermo-oxidative aging, damp-heat yellowing, and nitrogen oxide yellowing as the core objectives. This makes it difficult to simultaneously improve aging resistance, mechanical stability, and environmental safety. Therefore, developing a polyurethane foaming material with a highly efficient and stable antioxidant system, inhibiting oxidation and yellowing from multiple dimensions including raw material structure, reaction pathway, and anti-aging mechanism, is of significant engineering value and practical importance for improving the service life and long-term stability of home products such as pillows and mattresses, while also meeting the weather resistance requirements of automotive interiors and other scenarios. This will drive the development of high-end flexible foaming materials towards green, long-lasting, and high-performance applications.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide an antioxidant foaming material and its preparation method, thereby overcoming the defects in the prior art.

[0007] To achieve the above objectives, the present invention provides an antioxidant foaming material, which is formed by mixing and reacting component A and component B in a weight ratio of 100:30-50; Component A comprises the following raw materials in parts by weight: 90-100 parts of basic polyether composition, 1-4 parts of water, 0.5-2 parts of organosilicon surfactant, 0.3-1.5 parts of complex amine catalyst, and 0.5-2 parts of complex antioxidant; The basic polyether composition is a compound of white oil polyether polyol and trifunctional polyether polyol; Component B is toluene diisocyanate, which is a mixture of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate.

[0008] Furthermore, preferably, the weight ratio of white oil polyether polyol to trifunctional polyether polyol in the base polyether composition is 40-60:30-50.

[0009] Furthermore, preferably, the hydroxyl value of the white oil polyether polyol is 26-32 mgKOH / g; and the hydroxyl value of the trifunctional polyether polyol is 20-40 mgKOH / g.

[0010] Furthermore, preferably, the organosilicon surfactant is a polysiloxane-polyoxyolefin block copolymer.

[0011] Furthermore, preferably, the composite amine catalyst is composed of at least two of triethylenediamine, bis(dimethylaminoethyl) ether, and N,N-dimethylcyclohexylamine.

[0012] Furthermore, preferably, the composite antioxidant is a combination of hindered phenolic antioxidants and phosphite antioxidants.

[0013] Furthermore, preferably, the proportion of 2,4-toluene diisocyanate in component B is 80%, the proportion of 2,6-toluene diisocyanate is 20%, and the isocyanate index is 1.00-1.10.

[0014] This invention also provides a method for preparing an antioxidant foaming material, comprising the following steps: S1: Mix and stir the basic polyether composition, water, organosilicon surfactant, complex amine catalyst and complex antioxidant evenly to obtain component A; S2: Mix components A and B evenly and then feed them into a high-pressure foaming machine for mixing and foaming at a material temperature of 20-30℃ and a pressure of 10-20Mpa. S3: The foam obtained from the S2 foaming reaction is aged at room temperature for 15-30 hours to obtain the antioxidant foam material.

[0015] Furthermore, as a preferred embodiment, the curing conditions in step S3 are to place the food at room temperature for 24 hours.

[0016] Furthermore, as a preferred embodiment, the material obtained by the method is used in home pillow cores, mattresses, cushions, car seats, car headrests, and car armrest interiors.

[0017] Compared with the prior art, one aspect of the present invention has the following beneficial effects: This invention uses a metal-free composite amine catalyst that is completely free of metal components such as tin, bismuth, and zinc. This avoids the catalytic acceleration effect of metal ions on the oxidative degradation reaction, significantly delays the thermal and oxidative decomposition and mechanical decay of polyurethane segments, and improves the environmental friendliness of the material, meeting the requirements for low toxicity and low residue in home and automotive interiors. This invention uses a basic polyether composition as the main body instead of a traditional polymer polyol, which can eliminate the easily oxidized sites caused by unsaturated grafted segments and residual double bonds in traditional polymer polyols, thereby reducing the tendency of thermo-oxidative aging and yellowing from the source of raw materials, making the material structure more stable and stronger in aging resistance. The preparation process of this invention is simple and stable. The method of foaming before curing can make the reaction more complete and the cross-linking more thorough, thereby improving the structural uniformity while ensuring molding efficiency. Attached Figure Description

[0018] Figure 1 This is a schematic diagram showing the foaming materials obtained in Examples 1-5 being baked in an oven at 85°C and 85% humidity for 4 hours. Figure 2 This is a schematic diagram showing the foaming materials obtained in Comparative Examples 1-4 being baked in an oven at 85°C and 85% humidity for 4 hours. Detailed Implementation

[0019] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0020] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components. Example 1:

[0021] An antioxidant foaming material is prepared by mixing and reacting component A and component B in a weight ratio of 100:40; wherein component A includes: 50 parts of 2045 white oil polyether polyol, 50 parts of 5616s trifunctional polyether polyol, 2.5 parts of water, 1.0 part of 8244 silicone oil, 0.6 parts of A33 triethylenediamine catalyst, 0.2 parts of bis(dimethylaminoethyl) ether catalyst, and 1.0 parts of hindered phenolic antioxidant and phosphite antioxidant; component B is TDI-80 (2,4-TDI accounts for 80%, 2,6-TDI accounts for 20%).

[0022] Preparation method: S1: 2045 white oil polyether polyol, 5616s trifunctional polyether polyol, water, 8244 silicone oil, A33 triethylenediamine catalyst, bis(dimethylaminoethyl) ether catalyst, hindered phenolic antioxidant and phosphite antioxidant are added to a mixing tank and stirred evenly to obtain component A. S2: Mix component A with component B TDI-80 (80% 2,4-TDI and 20% 2,6-TDI), and feed the mixture into a high-pressure foaming machine. Control the material temperature at 25℃ and the pressure at 15MPa for mixing and foaming. S3: The foam obtained from the S2 foaming reaction is aged at room temperature for 24 hours to obtain an antioxidant foam material. Example 2:

[0023] An antioxidant foaming material is prepared by mixing and reacting component A and component B in a weight ratio of 100:38; wherein component A includes: 45 parts of 2045 white oil polyether polyol, 55 parts of 5616s trifunctional polyether polyol, 2.2 parts of water, 0.9 parts of 8244 silicone oil, 0.5 parts of A33 triethylenediamine catalyst, 0.4 parts of bis(dimethylaminoethyl) ether catalyst, and 1.2 parts of hindered phenolic antioxidant and phosphite antioxidant; component B is TDI-80 (2,4-TDI accounts for 80%, 2,6-TDI accounts for 20%).

[0024] The preparation method is the same as in Example 1. Example 3:

[0025] An antioxidant foaming material is prepared by mixing and reacting component A and component B in a weight ratio of 100:42; wherein component A includes: 55 parts of 2045 white oil polyether polyol, 45 parts of 5616s trifunctional polyether polyol, 2.8 parts of water, 1.1 parts of 8244 silicone oil, 0.5 parts of A33 triethylenediamine catalyst, 0.2 parts of bis(dimethylaminoethyl) ether catalyst, and 0.8 parts of hindered phenolic antioxidant and phosphite antioxidant; component B is TDI-80 (2,4-TDI accounts for 80%, 2,6-TDI accounts for 20%).

[0026] The preparation method is the same as in Example 1. Example 4:

[0027] An antioxidant foaming material is prepared by mixing and reacting component A and component B in a weight ratio of 100:35; wherein component A includes: 40 parts of 2045 white oil polyether polyol, 55 parts of 5616s trifunctional polyether polyol, 2.0 parts of water, 0.8 parts of 8244 silicone oil, 0.8 parts of A33 triethylenediamine catalyst, 0.2 parts of bis(dimethylaminoethyl) ether catalyst, and 1.0 parts of hindered phenolic antioxidant and phosphite antioxidant; component B is TDI-80 (2,4-TDI accounts for 80%, 2,6-TDI accounts for 20%).

[0028] The preparation method is the same as in Example 1. Example 5:

[0029] An antioxidant foaming material is prepared by mixing and reacting component A and component B in a weight ratio of 100:45; wherein component A includes: 60 parts of 2045 white oil polyether polyol, 38 parts of 5616s trifunctional polyether polyol, 3.0 parts of water, 1.2 parts of 8244 silicone oil, 0.4 parts of A33 triethylenediamine catalyst, 0.4 parts of bis(dimethylaminoethyl) ether catalyst, and 1.0 parts of hindered phenolic antioxidant and phosphite antioxidant; component B is TDI-80 (2,4-TDI accounts for 80%, 2,6-TDI accounts for 20%).

[0030] The preparation method is the same as in Example 1.

[0031] Comparative Example 1: The difference from Example 1 is that 50 parts of 2045 white oil polyether polyol and 50 parts of 5616s trifunctional polyether polyol are replaced with 70 parts of 2045 white oil polyether polyol and 30 parts of polymer polyol, while the other components remain unchanged.

[0032] Comparative Example 2: The difference from Example 1 is that component B is a mixture of TDI-80 and MDI in a 7:3 ratio, instead of using TDI-80 alone. The other components and processes remain unchanged.

[0033] Comparative Example 3: The difference from Example 1 is that no antioxidant is added to component A, while the other components and processes remain unchanged.

[0034] Comparative Example 4: The difference from Example 1 is that 0.4 parts of A33 triethylenediamine catalyst and 0.4 parts of bis(dimethylaminoethyl) ether catalyst are replaced with 0.4 parts of triethylenediamine and 0.4 parts of stannous octoate.

[0035] The foamed materials obtained in Examples 1-5 and Comparative Examples 1-4 were baked in an oven at 85°C and 85% humidity for 4 hours. The results are as follows: Figure 1 , Figure 2 As shown.

[0036] The mechanical properties of the foamed materials obtained in Examples 1-5 and Comparative Examples 1-4 were tested, and the test results are shown in Tables 1 and 2 below.

[0037] The density test refers to GB / T 6343-2009; the tensile strength and elongation at break test refers to GB / T 6344-2008; the 50% compressive stress refers to ISO 3386 / 1; the resilience coefficient test refers to GB / T 6670-2008; the compression set test refers to GB / T 6669-2008 (test conditions: compression ratio 75%, test temperature 70℃, test time 22h); the heat aging performance test refers to GB / T 3512-2018, the sample is placed in a 120℃ forced-air drying oven for 7 days of heat aging, after which it is taken out and conditioned in a standard environment for 3 hours, the tensile strength or hardness is tested, and the retention rate is calculated.

[0038] The test results show that the foamed materials prepared in Examples 1-5 of this invention all have a density of 34-36 kg / m³. 3 Within the comfortable range, the rebound coefficient is greater than 54%, and the compression set is controlled within 5.0%; indicating that the formulation system of the present invention (metal-free amine catalyst + specific polyether combination) has excellent process tolerance, and can maintain excellent physical and mechanical properties and dimensional stability regardless of the polyether ratio (Examples 2-5) or the water volume.

[0039] Although Comparative Example 1 maintained good support (hardness 135N), its compression set (9.5%) was significantly higher than that of the present invention group, indicating that the use of polymer polyols (POP) containing unsaturated double bonds reduces the material's resistance to heat and oxygen aging, which can easily lead to the mattress collapsing after long-term use.

[0040] Comparative Example 2, due to the introduction of MDI, resulted in an excessively high density of the foamed material (>42 kg / m³). 3 It also feels stiff (with only 48% rebound), making it unsuitable as a bedding material that comes into close contact with the body.

[0041] Compared with Examples 3 and 4, the hardness retention rates after thermal aging were only 64% and 74%, respectively, and the compression set was as high as 18.5% and 13.2%, respectively. This shows that the synergistic protection of "metal-free catalyst" and "composite antioxidant" makes the polyurethane material extremely prone to mechanical property degradation under heat.

[0042] This invention, by eliminating the source of metal ions and combining it with a highly efficient antioxidant system, successfully increases the hardness retention rate to over 90%, fundamentally solving the technical problems of easy aging and collapse of materials.

[0043] As can be seen from the figure, the foamed material prepared using the formula and process of this invention has superior antioxidant properties.

[0044] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. An antioxidant foaming material, characterized in that: It is prepared by mixing and reacting components A and B in a weight ratio of 100:30-50; Component A comprises the following raw materials in parts by weight: 90-100 parts of basic polyether composition, 1-4 parts of water, 0.5-2 parts of organosilicon surfactant, 0.3-1.5 parts of complex amine catalyst, and 0.5-2 parts of complex antioxidant; The basic polyether composition is a compound of white oil polyether polyol and trifunctional polyether polyol; Component B is toluene diisocyanate, which is a mixture of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate.

2. The antioxidant foaming material according to claim 1, characterized in that: The weight ratio of white oil polyether polyol to trifunctional polyether polyol in the basic polyether composition is 40-60:30-50.

3. The antioxidant foaming material according to claim 2, characterized in that: The white oil polyether polyol has a hydroxyl value of 26-32 mgKOH / g; the trifunctional polyether polyol has a hydroxyl value of 20-40 mgKOH / g.

4. The antioxidant foaming material according to claim 1, characterized in that: The organosilicon surfactant is a polysiloxane-polyoxyolefin block copolymer.

5. The antioxidant foaming material according to claim 1, characterized in that: The composite amine catalyst is composed of at least two of the following: triethylenediamine, bis(dimethylaminoethyl) ether, and N,N-dimethylcyclohexylamine.

6. The antioxidant foaming material according to claim 1, characterized in that: The composite antioxidant is a combination of hindered phenolic antioxidants and phosphite antioxidants.

7. The antioxidant foaming material according to claim 1, characterized in that: The proportion of 2,4-toluene diisocyanate in component B is 80%, the proportion of 2,6-toluene diisocyanate is 20%, and the isocyanate index is 1.00-1.

10.

8. A method for preparing an antioxidant foaming material according to any one of claims 1-7, characterized in that: Includes the following steps: S1: Mix and stir the basic polyether composition, water, organosilicon surfactant, complex amine catalyst and complex antioxidant evenly to obtain component A; S2: Mix components A and B evenly and then feed them into a high-pressure foaming machine for mixing and foaming at a material temperature of 20-30℃ and a pressure of 10-20Mpa. S3: The foam obtained from the S2 foaming reaction is aged at room temperature for 15-30 hours to obtain the antioxidant foam material.

9. The method for preparing an antioxidant foaming material according to claim 8, characterized in that: The maturation conditions for step S3 are: placing the food at room temperature for 24 hours.

10. The method for preparing an antioxidant foaming material according to claim 8, characterized in that: The material obtained by the method can be used in home pillow cores, mattresses, cushions, car seats, car headrests, and car armrest interiors.

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