Waste soft polyurethane foam-based regenerated board as well as preparation method and application thereof
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-17
- Publication Date
- 2026-03-24
AI Technical Summary
Waste polyurethane foam is difficult to recycle effectively. Traditional treatment methods cause environmental pollution and waste resources, while chemical degradation methods are costly. Existing technologies cannot achieve green and environmentally friendly recycling.
Waste flexible polyurethane foam is pretreated and crushed, then mixed with water-based polyurethane binder, activated, hot-pressed under high temperature steam, and cured to prepare recycled boards based on waste flexible polyurethane foam.
This technology enables the efficient recycling of waste flexible polyurethane foam. The resulting recycled boards have high strength, fast curing speed, and excellent dimensional stability, making them widely applicable. Furthermore, the manufacturing process is environmentally friendly and produces no secondary pollution.
Smart Images
Figure CN121718149A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of renewable materials, in particular to a waste soft polyurethane foam-based renewable board and a preparation method and application thereof. BACKGROUND
[0002] In 2025, the production and sales of polyurethane in China ranked first in the world, but a large amount of waste foam generated in production is difficult to degrade, occupies land and pollutes the environment, and recycling has become an industry problem.
[0003] For the recycling of waste polyurethane foam, the chemical degradation method has the limitations of complex process and high cost. The traditional landfill and incineration method will cause air pollution, and the protein resources contained in the waste cannot be effectively utilized, and the landfill method is easy to pollute the surface environment and groundwater resources. Therefore, it is urgent to provide a green and environmentally friendly waste polyurethane recycling method. SUMMARY
[0004] In order to solve the above technical problems, the purpose of the present application is to provide a waste soft polyurethane foam-based renewable board and a preparation method and application thereof. The preparation method of the present application is simple, environmentally friendly, low in loss and will not cause secondary pollution. The waste soft polyurethane foam-based renewable board prepared by the preparation method of the present application has high strength, fast curing speed, excellent dimensional stability and wide application prospect.
[0005] The technical solution of the present application to solve the above technical problems is as follows: The first purpose of the present application is to provide a preparation method of a waste soft polyurethane foam-based renewable board, comprising the following steps: (1) mixing the waste soft polyurethane foam after pretreatment and crushing to obtain mixed waste polyurethane fragments; (2) injecting a water-based polyurethane adhesive into the mixed waste polyurethane fragments and sequentially performing activation, high-temperature steam hot pressing and curing to obtain a waste soft polyurethane foam-based renewable board.
[0006] The present application has the following beneficial effects: the polyurethane foam waste board prepared by the present application uses waste soft polyurethane foam as raw material, and the waste soft polyurethane foam is crushed and bonded with adhesive without changing its chemical structure. The physical form is changed and directly utilized, and the regeneration rate is more than 90%, and the application is wide. The present application reduces the environmental impact of the accumulation of waste soft polyurethane foam, and the preparation method is simple, environmentally friendly, low in loss and will not cause secondary pollution. The waste soft polyurethane foam-based renewable board prepared by the preparation method of the present application has high strength, fast curing speed and excellent dimensional stability, and the product meets and exceeds the industry standard, and has wide application prospect.
[0007] Based on the above technical solution, the present invention can be further improved as follows.
[0008] Furthermore, the side length of the mixed waste polyurethane fragments mentioned in step (1) is 5mm to 25mm.
[0009] The advantages of adopting the above-mentioned further solution are: it is simple and convenient, saves time and effort, and the fragments are less likely to cause secondary pollution compared to powder.
[0010] Furthermore, in step (2), the mass ratio of the mixed waste polyurethane fragments to the water-based polyurethane adhesive is 3~5:1.
[0011] Furthermore, the specific operation of activation in step (2) is to heat to 25℃~80℃ and keep warm for 0.5h~2.5h.
[0012] Furthermore, the temperature of the high-temperature steam hot pressing molding in step (2) is 100℃~180℃.
[0013] Furthermore, the compression degree of the high-temperature steam hot pressing molding in step (2) is 5%~50%; the steam flow velocity is 5m / s~30m / s; and the reaction time is 0.5h~2h.
[0014] The beneficial effects of adopting the above-mentioned further solutions are: the present invention uses a high-temperature steam hot pressing molding process, which results in more uniform heating during the preparation process, improves the surface properties of recycled waste soft polyurethane foam-based boards, and has lower energy consumption, which helps to reduce production costs and is suitable for large-scale production.
[0015] Furthermore, the ripening temperature in step (2) is 40℃~60℃, and the time is 5h~24h.
[0016] Furthermore, the humidity of the ripening process in step (2) is 50% to 80%.
[0017] The beneficial effect of adopting the above-mentioned further scheme is that it allows the waste flexible polyurethane and water-based polyurethane adhesive to react fully within a certain period of time, achieving the best composite strength.
[0018] The second objective of this invention is to provide a recycled board material based on waste flexible polyurethane foam.
[0019] The third objective of this invention is to provide an application of recycled waste flexible polyurethane foam-based panels, which are used in the preparation of environmentally friendly recycled insulation panels. Attached Figure Description
[0020] Figure 1 This refers to the recycled board material based on waste flexible polyurethane foam prepared in Example 1 of the present invention. Detailed Implementation
[0021] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.
[0022] Example 1: Preparation of recycled flexible polyurethane foam-based boards (1) The waste soft polyurethane foam is pretreated and crushed into fragments with an average particle size of 5 mm. The impurities in the fragments are screened out and mixed evenly to obtain waste polyurethane fragments. (2) The waste polyurethane fragments and the commercially available two-component waterborne polyurethane adhesive with a solid content of 35~55% are mixed at a mass ratio of 3:1 and heated to 25°C. The mixture is then injected into a mold for preparing the insulation board and kept at that temperature for 0.5h. The temperature is then raised to 100°C and steam is used for hot pressing for 0.5h, where the steam flow rate is 17m / s and the compression degree is 5%. After hot pressing, the compressed product is demolded and placed in a curing chamber at a temperature of 40°C and a humidity of 50% for 5h to obtain the waste soft polyurethane foam-based recycled board.
[0023] Example 2: Preparation of recycled flexible polyurethane foam-based boards (1) The waste soft polyurethane foam is pretreated and crushed into fragments with an average particle size of 15 mm. Impurities in the fragments are screened out and mixed evenly to obtain waste polyurethane fragments. (2) The waste polyurethane fragments and the commercially available two-component waterborne polyurethane adhesive with a solid content of 35~55% are mixed at a mass ratio of 4:1 and heated to 50°C. The mixture is then injected into a mold for preparing the insulation board and kept at that temperature for 1.5h. The temperature is then raised to 140°C and steam is used for hot pressing for 1.5h. The steam flow rate is 30m / s and the compression degree is 25%. After hot pressing, the compressed product is demolded and placed in a curing chamber at a temperature of 50°C and a humidity of 65% for 15h to obtain the waste soft polyurethane foam-based recycled board.
[0024] Example 3: Preparation of recycled flexible polyurethane foam-based boards (1) The waste soft polyurethane foam is pretreated and crushed into fragments with an average particle size of 25 mm. Impurities in the fragments are screened out and mixed evenly to obtain waste polyurethane fragments. (2) The waste polyurethane fragments and the commercially available two-component waterborne polyurethane adhesive with a solid content of 35~55% are mixed at a mass ratio of 5:1 and heated to 80°C. The mixture is then injected into a mold for preparing the insulation board and kept at that temperature for 3 hours. The temperature is then raised to 180°C and steam is used for hot pressing for 2 hours. The steam flow rate is 5m / s and the compression degree is 50%. After hot pressing, the compressed product is demolded and placed in a curing chamber with a temperature of 60°C and a humidity of 80% for 24 hours to obtain the waste soft polyurethane foam-based recycled board.
[0025] Comparative Example 1: Preparation of Recycled Boards Based on Waste Flexible Polyurethane Foam The only difference between this comparative example and Example 1 is that the side length of the mixed waste polyurethane fragments in step (1) is 1 mm, while the other steps and conditions are the same as in Example 1.
[0026] Comparative Example 2: Preparation of Recycled Boards Based on Waste Flexible Polyurethane Foam The only difference between this comparative example and Example 1 is that the side length of the mixed waste polyurethane fragments in step (1) is 100 mm, while the other steps and conditions are the same as in Example 1.
[0027] Comparative Example 3: Preparation of Recycled Boards Based on Waste Flexible Polyurethane Foam The only difference between this comparative example and Example 1 is that the mass ratio of the mixed waste polyurethane fragments and water-based polyurethane adhesive in step (2) is 1:1. All other steps and conditions are the same as in Example 1.
[0028] Comparative Example 4: Preparation of Recycled Flexible Polyurethane Foam-Based Boards The only difference between this comparative example and Example 1 is that the mass ratio of the mixed waste polyurethane fragments and water-based polyurethane adhesive in step (2) is 10:1. All other steps and conditions are the same as in Example 1.
[0029] Comparative Example 5: Preparation of Recycled Flexible Polyurethane Foam-Based Boards The only difference between this comparative example and Example 1 is that the activated high-temperature steam hot pressing molding in step (2) is replaced by hot pressing molding, with the condition of hot pressing molding at 180°C for 2 hours. The other steps and conditions are the same as in Example 1.
[0030] Performance testing: The performance was tested according to the national standard GB / T 10802-2023 "General-purpose flexible polyurethane foam". The test results are shown in Table 1. Table 1 From Table 1, we can obtain: Each of Examples 1 to 3 meets the performance requirements of GB / T 10802-2023 "General Flexible Polyurethane Foam Plastics", and the length, width and thickness variation rates of the recycled waste flexible polyurethane foam-based boards prepared in Examples 1 to 3 are all ≤1%.
[0031] Compared to Comparative Example 5, the preparation method of this invention is simple, environmentally friendly, and has low waste, without causing secondary pollution. Compared to Comparative Examples 1, 2, 3, and 4, the recycled waste flexible polyurethane foam-based boards prepared by the method of this invention have low cost, high strength, fast curing speed, and excellent dimensional stability, and have broad application prospects.
[0032] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A method for preparing recycled boards based on waste flexible polyurethane foam, characterized in that, Includes the following steps: (1) Waste soft polyurethane foam is pretreated, crushed, and then mixed to obtain mixed waste polyurethane fragments; (2) A water-based polyurethane binder is injected into the mixed waste polyurethane fragments and activated, hot-pressed by high temperature steam, and cured in sequence to obtain waste soft polyurethane foam-based recycled board.
2. The method for preparing a recycled board based on waste flexible polyurethane foam according to claim 1, characterized in that, The side length of the mixed waste polyurethane fragments mentioned in step (1) is 5 mm to 25 mm.
3. The method for preparing a recycled board based on waste flexible polyurethane foam according to claim 1, characterized in that, The mass ratio of the mixed waste polyurethane fragments and the water-based polyurethane adhesive in step (2) is 3~5:
1.
4. The method for preparing a recycled board based on waste flexible polyurethane foam according to claim 1, characterized in that, The specific operation of activation in step (2) is to heat to 25℃~80℃ and keep warm for 0.5h~2.5h.
5. The method for preparing a recycled board based on waste flexible polyurethane foam according to claim 1, characterized in that, The temperature for high-temperature steam hot pressing in step (2) is 100℃~180℃.
6. The method for preparing a recycled board based on waste flexible polyurethane foam according to claim 1, characterized in that, The compression degree of the high-temperature steam hot pressing molding in step (2) is 5%~50%; the steam flow velocity is 5m / s~30m / s; and the reaction time is 0.5h~2h.
7. The method for preparing a recycled board based on waste flexible polyurethane foam according to claim 1, characterized in that, The ripening temperature in step (2) is 40℃~60℃, and the time is 5h~24h.
8. The method for preparing a recycled board based on waste flexible polyurethane foam according to claim 7, characterized in that, The aging humidity in step (2) is 50%~80%.
9. A recycled board material based on waste flexible polyurethane foam, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 8.
10. An application of a recycled board based on waste flexible polyurethane foam, characterized in that, The waste flexible polyurethane foam recycled board of claim 9 is used in the preparation of environmentally friendly recycled insulation board.