A renewable high-property water-based solvent-free polyurethane synthetic leather and its preparation method and application

Abstract

The present invention relates to a renewable high-property water-based solvent-free polyurethane synthetic leather and its preparation method and application. The preparation method comprises the following steps: S1, coating a layer of solvent-free polyurethane foaming slurry 1 on a water-impregnated recycled base fabric to obtain a recycled base fabric layer; S2, coating a layer of water-based polyurethane slurry on a release paper and drying the slurry to obtain a surface layer; S3, coating a layer of high-solid polyurethane slurry on the surface layer and drying the slurry to obtain a high-solid grafting layer; S4, coating a layer of solvent-free polyurethane foaming slurry 2 on the high-solid grafting layer, drying the slurry until semi-dry, and then laminating the slurry with the recycled base fabric layer, drying the solvent-free polyurethane foaming layer, peeling off the release paper, and aging at room temperature. The solvent-free polyurethane foaming layer of the present invention adopts a two-step process to improve the bonding strength between the solvent-free polyurethane foaming slurry and the recycled base fabric, and also to increase the bonding performance between the solvent-free polyurethane foaming slurry and the high-solid polyurethane slurry, so that the polyurethane product has high peeling performance and high physical properties.

Description

Technical Field

[0001] The present invention relates to the technical field of polyurethane synthetic leather, in particular to a renewable high-property water-based solvent-free polyurethane synthetic leather and a preparation method and application thereof. Background Art

[0002] Traditional polyurethane synthetic leather consists of a polyester or nylon base fabric, which is then processed into a polyurethane resin formed by the reaction of isocyanate and polyol. This new material, produced through synthetic leather processing, is widely used in footwear, packaging, sports equipment, sofas, and the automotive industry. The raw materials used are all fossil and non-renewable. To reduce the use of fossil materials, the reuse of recycled materials is urgently needed. Recycled materials can alleviate current resource shortages, reduce environmental pollution, and mitigate ecological damage. The recycling of recycled materials can achieve sustainable development of environmental resources and reduce environmental pollution.

[0003] In recent years, the development of solvent-free polyurethane synthetic leather has been rapid, with significant advancements in both technology research and development and production processes, creating new opportunities for the transformation and upgrading of the synthetic leather industry. Solvent-free synthetic leather products offer excellent environmental performance, good hydrolysis resistance, and superior styling properties, making them widely used in areas such as sofa leather, seat leather, and shoe leather. However, the current application of solvent-free polyurethane synthetic leather in the athletic shoe market remains limited. This is primarily due to the difficulty in achieving the basic physical properties required for athletic shoe materials, particularly peel strength. Even when these properties are met, production process control remains complex, making processing challenging. Summary of the Invention

[0004] In response to the technical problems existing in the prior art, the purpose of the present invention is to provide a renewable high-property water-based solvent-free polyurethane synthetic leather and its preparation method and application. The solvent-free polyurethane foam layer of the present invention adopts a "two-step method" processing technology, which can not only improve the bonding strength between the solvent-free polyurethane foam slurry and the recycled base cloth, but also increase the bonding performance between the solvent-free polyurethane foam slurry and the high-solid grafting layer, thereby improving the bonding strength between the recycled base cloth and the solvent-free polyurethane foam layer, so that the polyurethane product has the characteristics of high peeling performance and high physical properties.

[0005] To achieve the above objectives, the present invention adopts the following solutions.

[0006] The present invention provides a method for preparing a renewable high-property water-based solvent-free polyurethane synthetic leather, comprising the following steps:

[0007] S1, coating a layer of solvent-free polyurethane foaming slurry 1 on the water-impregnated recycled base fabric to obtain a recycled base material layer;

[0008] S2. coating a layer of water-based polyurethane slurry on the release paper and drying it to obtain a surface layer;

[0009] S3, coating a layer of high-solid polyurethane slurry on the surface layer, and drying to obtain a high-solid grafting layer;

[0010] S4. Coating a layer of solvent-free polyurethane foaming slurry 2 on the high-solid grafting layer, drying it until semi-dry and then laminating it with the recycled substrate layer, drying it to obtain a solvent-free polyurethane foam layer, peeling off the release paper, and aging it at room temperature to obtain a renewable high-property water-based solvent-free polyurethane synthetic leather.

[0011] The solvent-free polyurethane foam layer of the present invention adopts a "two-step" processing technology, which can not only improve the bonding strength between the solvent-free polyurethane foam slurry and the recycled base fabric, but also increase the bonding performance between the solvent-free polyurethane foam slurry and the high-solid grafting layer, thereby improving the bonding strength between the recycled base fabric and the solvent-free polyurethane foam layer, so that the polyurethane product has the characteristics of high peeling performance and high physical properties, and solves the problem of poor physical properties of the current water-based solvent-free polyurethane synthetic leather.

[0012] As a further improvement to the above-mentioned embodiment of the present invention, in step S1, the regenerated base fabric is a regenerated base fabric that has been treated with water-based polyurethane. The water-based polyurethane treatment comprises: dipping the regenerated base fabric in a water-based polyurethane slurry, then rolling it, coagulating it with acid, and drying it to set the shape. Preferably, the acid is oxalic acid having a concentration of 0.5% to 5%.

[0013] As a further improvement of the above-mentioned scheme of the present invention, the aqueous polyurethane slurry used for the aqueous polyurethane treatment is prepared from the following components in parts by mass: 100-200 parts of deionized water, 10-50 parts of anionic aqueous polyurethane resin, 0-0.8 parts of defoaming agent, 0-5 parts of thickener, and 0-2 parts of curing agent.

[0014] As a further improvement of the above solution of the present invention, in step S1, the regenerated base fabric is prepared by co-spinning at least one of regenerated PET, regenerated nylon, and regenerated clothing fiber.

[0015] As a further improvement of the above solution of the present invention, in step S1, the solvent-free polyurethane foaming slurry 1 is prepared by mixing component A1 and component B1 in a mass ratio of 1:0.90-1.0, wherein:

[0016] The component A1 is prepared from the following raw materials in parts by mass: 20-100 parts of polyether polyol, 20-100 parts of polyester polyol, 5-15 parts of small molecule chain extender, 0.025-0.05 parts of catalyst, and 0-40 parts of filler;

[0017] The component B1 is prepared from the following raw materials in parts by mass: 100 parts of isocyanate.

[0018] As a further improvement of the above solution of the present invention, in step S4, the second solvent-free polyurethane foaming slurry is prepared by mixing component A2 and component B2 in a mass ratio of 1:1.2-1.5, wherein:

[0019] The component A2 is prepared from the following raw materials in parts by weight: 20-100 parts of polyether polyol, 20-100 parts of polyester polyol, 5-15 parts of small molecule chain extender, 0.025-0.05 parts of catalyst, and 0-40 parts of filler;

[0020] The component B2 is prepared from the following raw materials in parts by mass: 100-150 parts of isocyanate.

[0021] As a further improvement of the above-mentioned scheme of the present invention, in step S2, the water-based surface polyurethane slurry is prepared from the following raw materials in parts by mass: 50-150 parts of polyether water-based polyurethane resin, 0-0.8 parts of defoaming agent, 0-5 parts of thickener, 1-3 parts of curing agent, and 0.2-1 parts of leveling agent.

[0022] As a further improvement of the above solution of the present invention, in step S3, the high-solid polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of a polyurethane resin with a solid content of 100% and 5-10 parts of a curing agent.

[0023] The present invention also provides a renewable high-property water-based solvent-free polyurethane synthetic leather, which is prepared by the above-mentioned method for preparing the renewable high-property water-based solvent-free polyurethane synthetic leather.

[0024] The present invention also proposes an application of the above-mentioned renewable high-property water-based solvent-free polyurethane synthetic leather in the manufacture of sports and leisure shoes.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The solvent-free polyurethane foam layer of the present invention adopts a two-step processing technology, which can not only improve the bonding strength between the solvent-free polyurethane foam slurry and the recycled base fabric, but also increase the bonding performance between the solvent-free polyurethane foam slurry and the high-solid polyurethane slurry, thereby improving the bonding strength between the recycled base fabric and the solvent-free polyurethane foam layer, so that the polyurethane product has the characteristics of high peeling performance and high physical properties, solving the problem of poor physical properties of current water-based solvent-free polyurethane synthetic leather.

[0027] 2. The recycled base fabric of the present invention is prepared by co-spinning recycled PET, recycled nylon or recycled clothing fiber, achieving 100% recyclability of the base material, perfectly combining the recycled and recyclable materials with solvent-free and environmentally friendly processing technology, and the recycled base fabric is treated with water-based polyurethane to effectively improve the support and realism of the base material.

[0028] 3. The present invention uses a high-solid grafting layer as a transition layer between the solvent-free polyurethane foam layer and the surface layer, which can effectively improve the bonding strength of the three and effectively improve the peeling strength of the synthetic leather.

[0029] 4. The renewable high-property water-based solvent-free polyurethane synthetic leather of the present invention has high physical properties, high peel strength, and excellent hydrolysis resistance, and can meet the requirements of polyurethane composite materials for sports and leisure shoes. The renewable high-property water-based solvent-free polyurethane synthetic leather of the present invention does not add or use any organic solvents during the processing process, thereby reducing production energy consumption and carbon emissions. DETAILED DESCRIPTION

[0030] To facilitate understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0032] The specific information of the raw materials used in the following examples and comparative examples is as follows:

[0033] (1) Anionic waterborne polyurethane resin: KT-702C, manufactured by Hefei Ketian Waterborne Technology Co., Ltd.

[0034] (2) Thickener: U605, manufactured by Wanhua Chemical Group Co., Ltd.

[0035] (3) Defoaming agent: SY-212D, manufactured by Jiangxi Mitsukoshi New Materials Co., Ltd.

[0036] (4) Curing agent

[0037] FN-15, manufactured by Shanghai Sisheng Polymer Materials Co., Ltd.

[0038] 166, the manufacturer is Wanhua Chemical Group Co., Ltd.

[0039] (5) Polyether polyols

[0040] Polyoxytetramethylene glycol, brand name PTMEG2000, produced by Chengdu Borite Chemical Technology Co., Ltd.

[0041] (6) Polyester polyols:

[0042] Polycarbonate diol, brand name YC-256, produced by Yuanli Chemical Group Co., Ltd.

[0043] (7) Small molecule chain extender: ethylene glycol, manufactured by Yangzi Petrochemical Co., Ltd.

[0044] (9) Catalyst

[0045] Catalyst, brand 90C-CC, manufactured by BASF AG.

[0046] (10) Filler: Kaolin, manufactured by Anhui Wanjiang Nanotechnology Co., Ltd.

[0047] (11) Isocyanate, brand AL-3055B, manufactured by Hefei Anli Polyurethane New Materials Co., Ltd.

[0048] The above reagents are only used to illustrate the sources and components of the reagents used in the experiments of the present invention so as to fully disclose the information, and do not mean that the present invention cannot be achieved by using other similar reagents or reagents provided by other suppliers.

[0049] Example 1

[0050] This embodiment provides a renewable high-property water-based solvent-free polyurethane synthetic leather, the preparation method of which includes the following four steps S1-S4.

[0051] S1. Coating a layer of solvent-free polyurethane foaming slurry 1 on the recycled base fabric treated with water-based polyurethane with a coating thickness of 0.1-0.2 mm to obtain a recycled base material layer.

[0052] In this embodiment, the recycled base fabric is a recycled PET needle-punched nonwoven fabric. The water-based polyurethane impregnation process involves: dipping the recycled PET needle-punched nonwoven fabric into the water-based polyurethane slurry, then rolling it onto rollers, coagulating it with acid, and drying it to set the shape. The resulting recycled base fabric is rolled up for use. The water-based polyurethane slurry is prepared from the following raw materials in parts by weight: 100 parts deionized water, 30 parts KT-702C, 0.5 parts defoamer SY-212D, 0.5 parts thickener U605, and 0.8 parts curing agent FN-15; the acid is 0.5% oxalic acid.

[0053] The solvent-free polyurethane foaming slurry was prepared by mixing component A1 and component B1 in a mass ratio of 1:0.90. Component A1 was prepared from the following raw materials in parts by mass: 60 parts of polyoxytetramethylene glycol (PTMEG2000), 40 parts of polycarbonate diol (YC-256), 10 parts of ethylene glycol, 0.08 parts of catalyst 90C-CC, and 20 parts of kaolin. Component A2 was prepared from the following raw materials in parts by mass: 100 parts of isocyanate AL-3055B.

[0054] S2. Apply a layer of water-based polyurethane slurry on the release paper with a knife to a thickness of 0.1-0.2 mm, and dry it at 90-130°C for 5-10 minutes to form a water-based surface layer.

[0055] The waterborne polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of polyether waterborne polyurethane resin KT-702C, 0.5 parts of defoamer SY-212D, 0.5 parts of thickener U605, 2 parts of curing agent 166, and 0.5 parts of leveling agent A-1.

[0056] S3. Apply a layer of high-solid polyurethane slurry on the water-based surface layer with a coating thickness of 0.1±0.01 mm, and dry it at 100° C.-140° C. for 5-10 minutes to obtain a high-solid grafting layer.

[0057] Among them, the high-solid polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of high-solid PU8408 and 5 parts of curing agent 166.

[0058] S4. Coat a layer of solvent-free polyurethane foaming slurry 2 on the high-solid grafting layer with a coating thickness of 0.3-0.4 mm, dry at 100°C-120°C for 2-3 minutes, bake until semi-dry, and then laminate it with the recycled substrate layer. Dry it in an oven at 120°C-140°C for 8-10 minutes to obtain a solvent-free polyurethane foam layer, peel off the release paper, and mature it at room temperature for 24 hours to obtain a renewable high-property water-based solvent-free polyurethane synthetic leather.

[0059] Solvent-free polyurethane foaming slurry 2 is prepared by mixing component A2 and component B2 in a mass ratio of 1:1.2. Component A2 is prepared from the following raw materials by mass: 60 parts of polyoxytetramethylene glycol PTMEG2000, 40 parts of polycarbonate diol YC-256, 10 parts of ethylene glycol, 0.08 parts of catalyst 90C-CC, and 20 parts of kaolin. Component B2 is prepared from the following raw materials by mass: 100 parts of isocyanate AL-3055B.

[0060] Example 2

[0061] This embodiment provides a renewable high-property water-based solvent-free polyurethane synthetic leather. The preparation method thereof adopts the implementation method of Example 1, but differs from Example 1 in that: in this embodiment, in step S1, in the solvent-free polyurethane foaming slurry 1, the mass ratio of component A1 and component B1 is 1:1; in step S4, in the solvent-free polyurethane foaming slurry 2, the mass ratio of component A2 and component B2 is 1:1.

[0062] Example 3

[0063] This embodiment provides a renewable high-property water-based solvent-free polyurethane synthetic leather. The preparation method thereof adopts the implementation method of Example 1, but differs from Example 1 in that: in this embodiment, in step S1, in the solvent-free polyurethane foaming slurry 1, the mass ratio of component A1 and component B1 is 1:1; in step S4, in the solvent-free polyurethane foaming slurry 2, the mass ratio of component A2 and component B2 is 1:1.3.

[0064] Example 4

[0065] This embodiment provides a renewable high-property water-based solvent-free polyurethane synthetic leather. The preparation method thereof adopts the implementation method of Example 1, but differs from Example 1 in that: in this embodiment, in step S1, in the solvent-free polyurethane foaming slurry 1, the mass ratio of component A1 and component B1 is 1:1; in step S4, in the solvent-free polyurethane foaming slurry 2, the mass ratio of component A2 and component B2 is 1:1.5.

[0066] Comparative Example 1

[0067] This comparative example proposes a water-based solvent-free polyurethane synthetic leather, and the preparation method thereof includes the following four steps S1-S4.

[0068] S1. Coating a layer of solvent-free polyurethane foaming slurry 1 on the recycled base fabric with a coating thickness of 0.1-0.2 mm to obtain a recycled base material layer.

[0069] In this comparative example, the recycled base fabric is recycled PET needle-punched non-woven fabric.

[0070] Solvent-free polyurethane foaming slurry A is prepared by mixing component A1 and component A2 in a mass ratio of 1:0.90. Component A1 is prepared from the following raw materials in parts by mass: 60 parts of polyoxytetramethylene glycol PTMEG2000, 40 parts of polycarbonate diol YC-256, 10 parts of ethylene glycol, 0.08 parts of catalyst 90C-CC, and 20 parts of kaolin. Component A2 is prepared from the following raw materials in parts by mass: 100 parts of isocyanate AL-3055B.

[0071] S2. Coat a layer of water-based polyurethane slurry on the release paper with a coating thickness of 0.1-0.2 mm, and dry at 90° C.-130° C. for 5-10 minutes to form a water-based surface layer.

[0072] The waterborne polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of polyether waterborne polyurethane resin KT-702C, 0.5 parts of defoamer SY-212D, 0.5 parts of thickener U605, 2 parts of curing agent 166, and 0.5 parts of leveling agent A-1.

[0073] S3. Apply a layer of high-solid polyurethane slurry with a thickness of 0.1±0.01 mm on the water-based surface layer, and dry it at 100° C.-140° C. for 5-10 minutes to obtain a high-solid grafting layer.

[0074] Among them, the high-solid polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of high-solid PU8408 and 5 parts of curing agent 166.

[0075] S4. Coat a layer of solvent-free polyurethane foaming slurry 2 on the water-based high-solid polyurethane layer with a coating thickness of 0.3-0.4 mm, dry at 100°C-120°C for 2-3 min, bake until semi-dry and then laminate with the recycled substrate layer, dry in an oven at 120°C-140°C for 8-10 min to obtain a solvent-free polyurethane foam layer, peel off the release paper, and mature at room temperature for 24 hours to obtain water-based solvent-free polyurethane synthetic leather.

[0076] Solvent-free polyurethane foaming slurry 2 is prepared by mixing component A2 and component B2 in a mass ratio of 1:1.2. Component A2 is prepared from the following raw materials by mass: 60 parts of polyoxytetramethylene glycol PTMEG2000, 40 parts of polycarbonate diol YC-256, 10 parts of ethylene glycol, 0.08 parts of catalyst 90C-CC, and 20 parts of kaolin. Component B2 is prepared from the following raw materials by mass: 100 parts of isocyanate AL-3055B.

[0077] Comparative Example 2

[0078] This comparative example proposes a water-based solvent-free polyurethane synthetic leather, and the preparation method thereof includes the following four steps S1-S4.

[0079] S1. The recycled base fabric is impregnated with water-based polyurethane to obtain a recycled base material layer.

[0080] In this embodiment, the recycled base fabric is a recycled PET needle-punched nonwoven fabric. The water-based polyurethane impregnation process involves: dipping the recycled PET needle-punched nonwoven fabric into the water-based polyurethane slurry, then rolling it onto rollers, coagulating it with acid, and drying it to set the shape. The resulting recycled base fabric is rolled up for use. The water-based polyurethane slurry is prepared from the following raw materials in parts by weight: 100 parts deionized water, 30 parts KT-702C, 0.5 parts defoamer SY-212D, 0.5 parts thickener U605, and 0.8 parts curing agent FN-15; the acid is 0.5% oxalic acid.

[0081] S2. Coat a layer of water-based polyurethane slurry on the release paper with a coating thickness of 0.1-0.2 mm, and dry at 90° C.-130° C. for 5-10 minutes to form a water-based surface layer.

[0082] The waterborne polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of polyether waterborne polyurethane resin KT-702C, 0.5 parts of defoamer SY-212D, 0.5 parts of thickener U605, 2 parts of curing agent 166, and 0.5 parts of leveling agent A-1.

[0083] S3. Then, a layer of high-solid polyurethane slurry with a thickness of 0.1±0.01 mm is applied on the water-based surface layer, and dried at 100° C.-140° C. for 5-10 minutes to obtain a high-solid grafting layer.

[0084] Among them, the high-solid polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of high-solid PU8408 and 5 parts of curing agent 166.

[0085] S4. Coat a layer of solvent-free polyurethane foaming slurry 2 on the high-solid grafting layer with a coating thickness of 0.3-0.4 mm, dry at 100°C-120°C for 2-3 min, bake until semi-dry and then laminate with the recycled substrate layer, dry in an oven at 120°C-140°C for 8-10 min to obtain a solvent-free polyurethane foaming layer, peel off the release paper, and mature at room temperature for 24 hours to obtain water-based solvent-free polyurethane synthetic leather.

[0086] Solvent-free polyurethane foaming slurry 2 is prepared by mixing component A2 and component B2 in a mass ratio of 1:1.2. Component A2 is prepared from the following raw materials by mass: 60 parts of polyoxytetramethylene glycol PTMEG2000, 40 parts of polycarbonate diol YC-256, 10 parts of ethylene glycol, 0.08 parts of catalyst 90C-CC, and 20 parts of kaolin. Component B2 is prepared from the following raw materials by mass: 100 parts of isocyanate AL-3055B.

[0087] Comparative Example 3

[0088] This embodiment provides a renewable high-property water-based solvent-free polyurethane synthetic leather, the preparation method of which includes the following three steps S1-S3.

[0089] S1. Coating a layer of solvent-free polyurethane foaming slurry 1 on the recycled base fabric treated with water-based polyurethane, with a coating thickness of 0.1-0.2 mm, to obtain a recycled base material layer.

[0090] In this embodiment, the recycled base fabric is a recycled PET needle-punched nonwoven fabric. The water-based polyurethane impregnation process involves: dipping the recycled PET needle-punched nonwoven fabric into the water-based polyurethane slurry, then rolling it onto rollers, coagulating it with acid, and drying it to set the shape. The resulting recycled base fabric is rolled up for use. The water-based polyurethane slurry is prepared from the following raw materials in parts by weight: 100 parts deionized water, 30 parts KT-702C, 0.5 parts defoamer SY-212D, 0.5 parts thickener U605, and 0.8 parts curing agent FN-15; the acid is 0.5% oxalic acid.

[0091] The solvent-free polyurethane foaming slurry was prepared by mixing component A1 and component B1 in a mass ratio of 1:0.90. Component A1 was prepared from the following raw materials in parts by mass: 60 parts of polyoxytetramethylene glycol (PTMEG2000), 40 parts of polycarbonate diol (YC-256), 10 parts of ethylene glycol, 0.08 parts of catalyst 90C-CC, and 20 parts of kaolin. Component B1 was prepared from the following raw materials in parts by mass: 100 parts of isocyanate AL-3055B.

[0092] S2. Coat a layer of water-based polyurethane slurry on the release paper with a coating thickness of 0.1-0.2 mm, and dry at 90° C.-130° C. for 5-10 minutes to form a water-based surface layer.

[0093] The waterborne polyurethane slurry is prepared from the following raw materials in parts by mass: 100 parts of polyether waterborne polyurethane resin KT-702C, 0.5 parts of defoamer SY-212D, 0.5 parts of thickener U605, 2 parts of curing agent 166, and 0.5 parts of leveling agent A-1.

[0094] S3. Apply a layer of solvent-free polyurethane foaming slurry 2 on the water-based surface layer with a coating thickness of 0.3-0.4 mm, dry at 100°C-120°C for 2-3 min, bake until semi-dry and then laminate with the recycled substrate layer, dry in an oven at 120°C-140°C for 8-10 min to obtain a solvent-free polyurethane foam layer, peel off the release paper, and mature at room temperature for 24 h to obtain water-based solvent-free polyurethane synthetic leather.

[0095] Solvent-free polyurethane foaming slurry 2 is prepared by mixing component A2 and component B2 in a mass ratio of 1:1.2. Component A2 is prepared from the following raw materials by mass: 60 parts of polyoxytetramethylene glycol PTMEG2000, 40 parts of polycarbonate diol YC-256, 10 parts of ethylene glycol, 0.08 parts of catalyst 90C-CC, and 20 parts of kaolin. Component B2 is prepared from the following raw materials by mass: 100 parts of isocyanate AL-3055B.

[0096] Test Case

[0097] The polyurethane synthetic leathers prepared in Examples 1-4 and Comparative Examples 1-3, as well as commercially available conventional polyurethane synthetic leather, were subjected to performance testing. The test results are shown in Table 1. The alkali solution used for immersion was 10% NaOH at 25°C for 24 hours. Peel strength and tensile strength were tested according to the methods specified in GB / T 8949-2008.

[0098] Table 1

[0099]

[0100]

[0101] The alkali solution used for immersion is 10% NaOH at a temperature of 25° C. for 24 hours. The peel strength and tensile strength test methods are the relevant methods in GB / T 8949-2008.

[0102] From the results in Table 1, it can be seen that the renewable high-property water-based solvent-free polyurethane synthetic leathers prepared in Examples 1-4 have high physical properties, high peel strength, and excellent hydrolysis resistance, indicating that the polyurethane synthetic leather produced by the two-step process of the present invention can meet the requirements of sports and leisure shoe materials.

[0103] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0104] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0105] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for preparing renewable high-property water-based solvent-free polyurethane synthetic leather, characterized in that: The following steps are involved: S1. Coating a layer of solvent-free polyurethane foaming slurry on the water-impregnated recycled base fabric to obtain a recycled base material layer; the recycled base fabric is a recycled base fabric treated with water-impregnated polyurethane, and the process of the water-impregnated polyurethane treatment is as follows: immersing the recycled base fabric in the water-impregnated polyurethane slurry, then rolling it, acid coagulating it, and drying it to set it; the water-impregnated polyurethane slurry used for the water-impregnated polyurethane treatment is prepared from the following components in parts by weight: 100-200 parts of deionized water, 10-50 parts of anionic water-based polyurethane resin , defoamer 0-0.8 parts, thickener 0-5 parts, curing agent 0-2 parts; the solvent-free polyurethane foaming slurry is prepared by mixing component A1 and component B1 in a mass ratio of 1:0.90-1.0, wherein: the component A1 is prepared from the following raw materials in parts by mass: 20-100 parts of polyether polyol, 20-100 parts of polyester polyol, 5-15 parts of small molecule chain extender, 0.025-0.05 parts of catalyst, and 0-40 parts of filler; the component B1 is prepared from the following raw materials in parts by mass: 100 parts of isocyanate; S2. coating a layer of water-based polyurethane slurry on the release paper and drying it to obtain a surface layer; S3, coating a layer of high-solid polyurethane slurry on the surface layer and drying to obtain a high-solid grafting layer; the high-solid polyurethane slurry is prepared from the following raw materials in parts by weight: 100 parts of a polyurethane resin with a solid content of 100% and 5-10 parts of a curing agent; S4. Coat a layer of solvent-free polyurethane foam slurry 2 on the high-solid grafting layer, bake it until semi-dry, and then laminate it with the recycled substrate layer. Dry it to obtain a solvent-free polyurethane foam layer, peel off the release paper, and mature it at room temperature to obtain a renewable high-property water-based solvent-free polyurethane synthetic leather; the solvent-free polyurethane foam slurry 2 is mixed by component A2 and component B2 in a mass ratio of 1:1.2-1.5, wherein: the component A2 is prepared from the following raw materials in parts by mass: 20-100 parts of polyether polyol, 20-100 parts of polyester polyol, 5-15 parts of small molecule chain extender, 0.025-0.05 parts of catalyst, and 0-40 parts of filler; the component B2 is prepared from the following raw materials in parts by mass: 100-150 parts of isocyanate.

2. The method for preparing renewable high-property water-based solvent-free polyurethane synthetic leather according to claim 1, characterized in that: In the step S1, the regenerated base fabric is prepared by co-spinning at least one of regenerated PET, regenerated nylon, and clothing regenerated fiber.

3. The method for preparing renewable high-property water-based solvent-free polyurethane synthetic leather according to claim 1, characterized in that: In step S2, the waterborne polyurethane slurry is prepared from the following raw materials in parts by mass: 50-150 parts of polyether waterborne polyurethane resin, 0-0.8 parts of defoaming agent, 0-5 parts of thickener, 1-3 parts of curing agent, and 0.2-1 parts of leveling agent.

4. A renewable high-property water-based solvent-free polyurethane synthetic leather, characterized in that: The synthetic leather is prepared by the method for preparing renewable high-property water-based solvent-free polyurethane synthetic leather according to any one of claims 1 to 3.

5. Use of the renewable high-property water-based solvent-free polyurethane synthetic leather as claimed in claim 4 in the manufacture of sports and leisure shoes.

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