Ultra-durable PVC foaming layer, ultra-durable PVC artificial leather and preparation method thereof

Abstract

This application relates to a super-durable PVC foam layer, comprising the following components by weight: 85-100 parts by weight of polyvinyl chloride resin, 30-50 parts by weight of a low- and high-temperature resistant plasticizer, 3-20 parts by weight of a carboxyl-terminated liquid nitrile rubber, and 6-10 parts by weight of an inorganic foaming agent. This application utilizes a low- and high-temperature resistant plasticizer to enhance the structural stability of the polyvinyl chloride resin, imparting both heat resistance and low-temperature flexibility. Furthermore, a carboxyl-terminated liquid nitrile rubber toughening agent is introduced to further optimize the polyvinyl chloride resin's folding resistance at low temperatures. Furthermore, a new mineral-based endothermic foaming agent is added to this layer to mitigate the defects of the microsphere foaming agent, thereby enhancing the folding resistance of the polyvinyl chloride resin and ultimately achieving super-durable PVC artificial leather.

Description

Technical Field

[0001] The present application relates to the technical field of automotive materials, and in particular to a super-durable PVC foam layer, a super-durable PVC artificial leather and a preparation method thereof. Background Art

[0002] Car seats are a crucial component of vehicle interiors and are also the component that sees the most prolonged contact between the driver and passengers during driving. Car seats are composed of leather, and the choice of leather not only impacts seat performance but also largely determines the overall vehicle interior and exterior quality. With the continuous development of the automotive interior industry, the durability, comfort, and softness of car seat leather are increasingly valued by consumers, impacting vehicle sales to a certain extent.

[0003] PVC artificial leather, as a composite material, is similar to natural leather and features softness, wear resistance, and fold resistance. It is generally composed of a mixture of polyvinyl chloride resin, plasticizers, stabilizers, and other additives. The mixed solution is coated or laminated onto a substrate and processed to produce PVC artificial leather. In recent years, due to global warming, extreme temperature fluctuations have become more frequent. As the probability of high and low temperatures increases, the requirements for PVC artificial leather are also increasing. In order to make PVC artificial leather have stronger low- and high-temperature folding resistance, it is necessary to develop a product with more competitive cost and better meet the ultra-durable leather performance requirements of automotive seats. Summary of the Invention

[0004] In order to improve the low-temperature and high-temperature folding resistance of PVC artificial leather and make the PVC artificial leather super durable, the present application provides a super durable PVC foam layer, a super durable PVC artificial leather and a preparation method thereof.

[0005] In the first aspect, the present application provides a super durable PVC foam layer, which adopts the following technical solutions:

[0006] The super durable PVC foam layer comprises the following components in parts by weight: 85-100 parts by weight of polyvinyl chloride resin, 30-50 parts by weight of low and high temperature resistant plasticizer, 3-20 parts by weight of carboxyl-terminated liquid nitrile rubber and 6-10 parts by weight of inorganic foaming agent.

[0007] By adopting the above technical solution, a low- and high-temperature resistant plasticizer is selected to improve the structural stability of the polyvinyl chloride resin, so that the polyvinyl chloride resin has both heat resistance and low-temperature flexibility, thereby reducing the extraction of the plasticizer and improving the low- and high-temperature folding resistance of the polyvinyl chloride resin; at the same time, a terminal carboxyl liquid nitrile rubber toughening agent is introduced to further improve the Tg of the polyvinyl chloride resin to optimize its folding resistance at a low temperature of -20°C, thereby further improving the low- and high-temperature folding resistance of the polyvinyl chloride resin.

[0008] Because the thermoplastic shell of the existing microsphere foaming agent has a higher plasticity than polyvinyl chloride, it easily becomes a potential stress concentration area during foaming, reducing the folding resistance of the polyvinyl chloride resin. By adopting an inorganic foaming agent, the continuous stress fatigue generated by the microsphere foaming agent on the gelled PVC is optimized, thereby repeatedly improving the folding resistance of the polyvinyl chloride resin and achieving ultra-durable performance of PVC artificial leather.

[0009] In a specific embodiment, the low-temperature and high-temperature resistant plasticizer is di(nonyl / undecyl) phthalate.

[0010] In a specific embodiment, the carboxyl-terminated liquid nitrile rubber is selected from the carboxyl-terminated liquid nitrile rubber of type CN-10-I or CN-10-II.

[0011] By adopting the above technical solution, the polyvinyl chloride resin is toughened with end-carboxyl liquid nitrile rubber and is compatible with the plasticizer before curing, thereby forming an "island structure" after gelation. It can absorb the energy impact caused by fatigue testing at low temperatures without basically reducing the heat resistance.

[0012] In a specific embodiment, the inorganic foaming agent is a mineral-based endothermic foaming agent, and the preparation steps are as follows:

[0013] The inorganic material is ground and sieved to obtain an inorganic material, and then ethanol and maleic anhydride are added to mix and disperse, and the mixture is reacted at 60-100° C. for 1-3 hours to obtain a mineral-based endothermic foaming agent.

[0014] By employing this technical solution, inorganic materials are grafted and modified with maleic anhydride grafts to create a mineral-based, endothermic foaming agent. Because maleic anhydride possesses both polar aldehyde groups and non-polar olefin segments, it significantly improves the compatibility between the grafted inorganic material and polyvinyl chloride resin. It also mitigates the persistent stress fatigue caused by bending of the gelled PVC due to the rigidity of the microsphere foaming agent's inherently rigid elastomeric microspheres, thereby enhancing the flexural strength of the polyvinyl chloride resin.

[0015] In a specific embodiment, the inorganic substance includes sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate or ammonium nitrite.

[0016] In a specific embodiment, the weight ratio of the inorganic substance, ethanol and maleic anhydride is 1:(1.5-2.5):(0.1-0.2).

[0017] In a second aspect, the present application provides a super durable PVC artificial leather, which adopts the following technical solution:

[0018] The super-durable PVC artificial leather comprises a PVC foam layer and a PVC skin layer. The PVC skin layer comprises the following components in parts by weight: 85-100 parts by weight of polyvinyl chloride resin, 30-50 parts by weight of a low- and high-temperature resistant plasticizer, 3-20 parts by weight of carboxyl-terminated liquid nitrile rubber, 3-8 parts by weight of a stabilizer, 3-15 parts by weight of modified wood cellulose, and 0.1-3 parts by weight of modified nano-silicon dioxide.

[0019] By adopting the above technical solution, a layer of foamed material is formed under the PVC skin layer through a foaming process, thus forming a PVC foam layer. As the raw material for the PVC skin layer, a low-temperature and high-temperature resistant plasticizer is selected to enhance the structural stability of the PVC resin, making the PVC resin both heat-resistant and low-temperature flexible, thereby reducing plasticizer extraction and improving the PVC resin's low-temperature and high-temperature flexural resistance. At the same time, a carboxyl-terminated liquid nitrile rubber toughening agent is introduced to further improve the Tg of the PVC resin and optimize its flexural resistance at low temperatures of -20°C, further enhancing the PVC resin's low-temperature and high-temperature flexural resistance.

[0020] Modified wood cellulose and modified nano-silica are added to the above basis. Lignin, as a common natural polymer material, contains hindered phenol structure in its molecular structure, which can effectively improve the heat resistance and aging resistance of the resin. However, due to the presence of a large number of active hydroxyl groups on its surface, the interfacial bonding force with the polyvinyl chloride resin is very weak. By adding modified silica to improve the compatibility between wood cellulose and polyvinyl chloride resin, the polyvinyl chloride resin can have better antibacterial, high temperature resistance, corrosion resistance and weather resistance.

[0021] In a specific embodiment, the mass ratio of the modified lignocellulose to the modified nano-silica is 10:(0.5-1.5).

[0022] In a specific embodiment, the modified lignocellulose is prepared as follows:

[0023] The lignocellulose and the silane coupling agent aqueous solution are mixed to prepare a mixed liquid, which is then evenly stirred, filtered and dried to obtain modified lignocellulose.

[0024] By adopting the above technical solution and using a silane coupling agent to graft-modify wood cellulose, it is beneficial to improve the compatibility between natural fibers and resin, thereby enhancing the interfacial strength of polyvinyl chloride resin and improving the tensile strength of polyvinyl chloride resin.

[0025] In a specific embodiment, the modified nano-silica is prepared as follows:

[0026] The nano-silica is dried for 8-16 hours, and then anhydrous ethanol is added to prepare a nano-silica solution; the nano-silica solution is then mixed with a silane coupling agent aqueous solution, and dispersed at 60-100° C. to obtain a modified nano-silica solution, which is finally obtained by filtering and drying.

[0027] By adopting the above technical solution, nano-silica is grafted and modified with a silane coupling agent, thereby solving the problem of easy agglomeration of particles caused by the large specific surface area and strong surface activity of nano-silica; at the same time, the modified nano-silica particles can react with the hydroxyl groups and phenolic hydroxyl groups on the lignocellulose to form hydrogen bonds, and can also form strong intermolecular forces with the polyvinyl chloride molecular chains, thereby greatly improving the compatibility between the poorly compatible lignocellulose and the polyvinyl chloride resin through the bridging effect of the nano-silica, thereby enhancing their surface bonding strength.

[0028] In a third aspect, the present application provides a method for preparing super-durable PVC artificial leather, which adopts the following technical solution:

[0029] The preparation method of durable PVC artificial leather comprises the following steps:

[0030] Prepare PVC skin layer slurry and PVC foam layer slurry according to the raw material ratio;

[0031] The PVC surface layer slurry is applied on the release paper, and the PVC surface layer is obtained after drying and forming; the PVC foam layer slurry is applied on the PVC surface layer, and the PVC foam layer is obtained after drying and forming; the PVC foam layer is then laminated to the base fabric to obtain PVC artificial leather.

[0032] By adopting the above technical solution, a PVC skin layer slurry is applied on a release paper to obtain a PVC skin layer, and a PVC foam layer slurry is applied on the PVC skin layer to obtain a PVC foam layer. The PVC foam layer is then laminated to a base fabric to finally obtain a super-durable PVC artificial leather.

[0033] In a specific embodiment, the PVC skin layer slurry is prepared as follows:

[0034] Accurately weigh polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica, stir and mix evenly, then add carboxyl-terminated liquid nitrile rubber and stabilizer, stir and mix evenly and evacuate to obtain a PVC skin layer slurry; the PVC foam layer slurry is prepared as follows:

[0035] Accurately weigh polyvinyl chloride resin, low-temperature resistant plasticizer and carboxyl-terminated liquid nitrile rubber, stir them evenly, then add inorganic foaming agent, mix and slurry to obtain PVC foam layer slurry.

[0036] In summary, this application includes at least one of the following beneficial technical effects:

[0037] 1. This application utilizes a low- and high-temperature resistant plasticizer to enhance the structural stability of polyvinyl chloride resin, so that the polyvinyl chloride resin has both heat resistance and low-temperature flexibility, thereby enhancing the low- and high-temperature folding resistance of the polyvinyl chloride resin; at the same time, a carboxyl-terminated liquid nitrile rubber toughening agent is introduced to further optimize the folding resistance of the polyvinyl chloride resin at low temperatures, thereby further enhancing the low- and high-temperature folding resistance of the polyvinyl chloride resin and achieving ultra-durable performance of PVC artificial leather.

[0038] 2. This application utilizes a new mineral-based endothermic foaming agent to solve the dispersion compatibility problem with polyvinyl chloride resin. At the same time, it can optimize the continuous stress fatigue caused by the microsphere foaming agent to gelled PVC, improve the folding resistance of polyvinyl chloride resin, and optimize amine residues, odor, and VOC, etc.

[0039] 3. In this application, modified wood cellulose and modified nano-silica are mixed and added to the PVC surface layer. The mixture of the two and the polyvinyl chloride resin is beneficial to improving the antibacterial and high-temperature resistance of the polyvinyl chloride resin; at the same time, the modified silica can improve the compatibility between wood cellulose and polyvinyl chloride resin and improve the dispersibility of wood cellulose. DETAILED DESCRIPTION

[0040] The polyvinyl chloride in this application was purchased from Formosa Plastics Corporation, model PR-440; the carboxyl-terminated liquid nitrile rubber was purchased from Tianyuan Aerospace Materials, model CN-10-I; the low-temperature and high-temperature resistant plasticizer was purchased from Kunrui Chemical, model DIPLAST L9-11; the wood cellulose was purchased from Wuxi Green Building Technology, model TM300; the silane coupling agent was specifically γ-aminopropyltriethoxysilane, model KH550; the stabilizer was specifically methyl tin mercaptan, purchased from Sendi Chemical, model stabilizer 181; the anti-ultraviolet agent model was triazine-5; the brand of the color paste was Meishikai The inorganic substance is specifically sodium bicarbonate; other raw materials can be obtained commercially.

[0041] Preparation Example

[0042] Preparation Example 1

[0043] First, γ-aminopropyltriethoxysilane, ethanol and water were mixed to prepare a silane coupling agent dilution solution with a mass ratio of 20:72:8. The solution was ultrasonically stirred at 25°C for 10 minutes. After mixing evenly, it was added to cellulose, where the mass percentage of γ-aminopropyltriethoxysilane was 1% of the cellulose. After stirring evenly, the solution was placed in an oven and dried at 100°C to obtain modified cellulose.

[0044] Preparation Example 2

[0045] γ-Aminopropyltriethoxysilane, ethanol and water were mixed to prepare a silane coupling agent mixed solution with a mass ratio of 20:72:8; nano-silica was dried at 100°C for 8 hours, and then anhydrous ethanol was added to prepare a nano-silica solution with a mass ratio of 1:25; then the nano-silica solution was mixed with the silane coupling agent mixed solution to prepare a mixed solution with a volume ratio of 1:1, and after mixing evenly, sodium hydroxide was added to adjust the pH to 9, and the mixture was allowed to stand for 30 minutes, subjected to high-speed shearing at 60°C for 20 minutes and ultrasonication for 20 minutes, and then filtered and dried at 120°C to obtain modified nano-silica.

[0046] Preparation Example 3

[0047] γ-Aminopropyltriethoxysilane, ethanol and water were mixed to prepare a silane coupling agent mixed solution with a mass ratio of 20:72:8; nano-silica was dried at 100°C for 16 hours, and then anhydrous ethanol was added to prepare a nano-silica solution with a mass ratio of 1:35; then the nano-silica solution was mixed with the silane coupling agent mixed solution to prepare a mixed solution with a volume ratio of 1:1, and after mixing evenly, sodium hydroxide was added to adjust the pH to 9, and the mixture was allowed to stand for 30 minutes, subjected to high-speed shearing at 100°C for 40 minutes and ultrasonication for 40 minutes, and then filtered and dried at 120°C to obtain modified nano-silica.

[0048] Preparation Example 4

[0049] Sodium bicarbonate was ground and sieved to obtain a uniform material with a particle size of 3-5 μm, and then ethanol and maleic anhydride were added to prepare a mixed solution with a mass ratio of 1:1.5:0.1. After ultrasonic dispersion for 5 minutes, the solution was stirred at 200 rpm at 60°C for 1 hour to obtain a mineral-based endothermic foaming agent.

[0050] Preparation Example 5

[0051] Sodium bicarbonate was ground and sieved to obtain a uniform material with a particle size of 3-5 μm, and then ethanol and maleic anhydride were added to prepare a mixed solution with a mass ratio of 1:2.5:0.2. After ultrasonic dispersion for 10 minutes, the solution was placed at 100°C and stirred at 200 rpm for 3 hours to obtain a mineral-based endothermic foaming agent.

[0052] Preparation Example 6

[0053] Ammonium bicarbonate was ground and sieved to obtain a uniform material with a particle size of 3-5 μm, and then ethanol and maleic anhydride were added to prepare a mixed solution with a mass ratio of 1:2:0.1. After ultrasonic dispersion for 5 minutes, the solution was stirred at 200 rpm at 60°C for 1 hour to obtain a mineral-based endothermic foaming agent.

[0054] Example

[0055] Example 1

[0056] The raw materials for preparing the super durable PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low and high temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 6g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0057] Accurately weigh polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, place them in a high-speed disperser and stir and mix them evenly, then add an inorganic foaming agent, stir for 40 minutes to mix evenly and release the slurry to obtain a PVC foam layer slurry;

[0058] The PVC foam layer slurry is scraped onto the release paper and dried at 200°C to obtain the PVC foam layer.

[0059] Example 2

[0060] The raw materials for preparing the super durable PVC foam layer include: 95g of polyvinyl chloride resin, 40g of low and high temperature resistant plasticizer, 12g of carboxyl-terminated liquid nitrile rubber, and 8g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0061] Accurately weigh polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, place them in a high-speed disperser and stir and mix them evenly, then add an inorganic foaming agent, stir for 40 minutes to mix evenly and release the slurry to obtain a PVC foam layer slurry;

[0062] The PVC foam layer slurry is scraped onto the release paper and dried at 200°C to obtain the PVC foam layer.

[0063] Example 3

[0064] The raw materials for preparing the super durable PVC foam layer include: 100g of polyvinyl chloride resin, 50g of low and high temperature resistant plasticizer, 20g of carboxyl-terminated liquid nitrile rubber, and 10g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0065] Accurately weigh polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, place them in a high-speed disperser and stir and mix them evenly, then add an inorganic foaming agent, stir for 40 minutes to mix evenly and release the slurry to obtain a PVC foam layer slurry;

[0066] The PVC foam layer slurry is scraped onto the release paper and dried at 200°C to obtain the PVC foam layer.

[0067] Example 4

[0068] The only difference between this embodiment and embodiment 1 is that the amount of carboxyl-terminated liquid nitrile rubber in the raw material for preparing the PVC skin layer is 20 g.

[0069] Example 5

[0070] The only difference between this embodiment and embodiment 1 is that the amount of low-temperature and high-temperature resistant plasticizer in the raw material for preparing the PVC skin layer is 50 g.

[0071] Example 6

[0072] The only difference between this embodiment and embodiment 1 is that the inorganic foaming agent is prepared by Preparation Example 5.

[0073] Example 7

[0074] The only difference between this embodiment and embodiment 1 is that the inorganic foaming agent is prepared by Preparation Example 6.

[0075] Example 8

[0076] The only difference between this embodiment and embodiment 1 is that the model of the carboxyl-terminated liquid nitrile rubber is CN-10-II.

[0077] Example 9

[0078] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0079] The raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 30g of low-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 3g of modified wood cellulose, and 0.1g of modified nano-silica; wherein the modified wood cellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0080] The raw materials for preparing the PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low-temperature and high-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 6g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0081] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0082] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0083] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0084] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0085] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0086] Example 10

[0087] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0088] The raw materials for preparing the PVC skin layer include: 95g of polyvinyl chloride resin, 40g of low-temperature resistant plasticizer, 12g of carboxyl-terminated liquid nitrile rubber, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0089] The raw materials for preparing the PVC foam layer include: 95g of polyvinyl chloride resin, 40g of low-temperature resistant plasticizer, 12g of carboxyl-terminated liquid nitrile rubber, and 8g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0090] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0091] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0092] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0093] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0094] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0095] Example 11

[0096] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0097] The raw materials for preparing the PVC skin layer include: 100g of polyvinyl chloride resin, 50g of low-temperature resistant plasticizer, 20g of carboxyl-terminated liquid nitrile rubber, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0098] The raw materials for preparing the PVC foam layer include: 100g of polyvinyl chloride resin, 50g of low-temperature resistant plasticizer, 20g of carboxyl-terminated liquid nitrile rubber, and 10g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0099] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0100] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0101] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0102] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0103] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0104] Example 12

[0105] The only difference between this embodiment and embodiment 9 is that the amount of carboxyl-terminated liquid nitrile rubber in the raw material for preparing the PVC skin layer is 20 g; the amount of carboxyl-terminated liquid nitrile rubber in the raw material for preparing the PVC foam layer is 20 g.

[0106] Example 13

[0107] The only difference between this embodiment and embodiment 9 is that the amount of low-temperature resistant plasticizer in the raw material for preparing the PVC skin layer is 50 g; the amount of low-temperature resistant plasticizer in the raw material for preparing the PVC skin layer is 50 g.

[0108] Example 14

[0109] The only difference between this embodiment and embodiment 9 is that the raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 30g of low and high temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 10g of modified wood cellulose, and 0.5g of modified nano-silica.

[0110] Example 15

[0111] The only difference between this embodiment and embodiment 9 is that the raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 30g of low and high temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 10g of modified wood cellulose, and 1.5g of modified nano-silica.

[0112] Example 16

[0113] The only difference between this embodiment and embodiment 9 is that the raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 30g of low and high temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 15g of modified wood cellulose, and 3g of modified nano-silica.

[0114] Example 17

[0115] The only difference between this embodiment and embodiment 9 is that the modified nano-silica is prepared by Preparation Example 3.

[0116] Example 18

[0117] The only difference between this embodiment and embodiment 9 is that the raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 30g of low and high temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 3.1g of modified nano-silica.

[0118] Example 19

[0119] The only difference between this embodiment and embodiment 9 is that the raw materials for preparing the PVC skin layer include: 85 g of polyvinyl chloride resin, 30 g of low and high temperature resistant plasticizer, 3 g of carboxyl-terminated liquid nitrile rubber, and 3.1 g of modified wood cellulose.

[0120] Example 20

[0121] The only difference between this embodiment and embodiment 9 is that the raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 30g of low and high temperature resistant plasticizer, and 3g of carboxyl-terminated liquid nitrile rubber.

[0122] Example 21

[0123] The only difference between this embodiment and embodiment 9 is that the inorganic foaming agent is prepared by Preparation Example 5.

[0124] Example 22

[0125] The only difference between this embodiment and embodiment 9 is that the inorganic foaming agent is prepared by Preparation Example 6.

[0126] Example 23

[0127] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0128] The raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 30g of low-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 3g of stabilizer, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0129] The raw materials for preparing the PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 3g of stabilizer, 6g of inorganic foaming agent, 0.1g of anti-ultraviolet agent, and 0.1g of color paste; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0130] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber and stabilizer are added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0131] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0132] Then, a PVC foam layer is prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, carboxyl-terminated liquid nitrile rubber, stabilizer, anti-ultraviolet agent and color paste, placing them in a high-speed disperser and stirring and mixing them evenly, and adding an inorganic foaming agent, stirring for 40 minutes to mix and then slurrying to obtain a PVC foam layer slurry;

[0133] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0134] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0135] Example 24

[0136] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0137] The raw materials for preparing the PVC skin layer include: 100g of polyvinyl chloride resin, 50g of low-temperature resistant plasticizer, 20g of carboxyl-terminated liquid nitrile rubber, 8g of stabilizer, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0138] The raw materials for preparing the PVC foam layer include: 100g of polyvinyl chloride resin, 50g of low-temperature resistant plasticizer, 20g of carboxyl-terminated liquid nitrile rubber, 8g of stabilizer, 10g of inorganic foaming agent, 3g of anti-ultraviolet agent, and 3g of color paste; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0139] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber and stabilizer are added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0140] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0141] Then, a PVC foam layer is prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, carboxyl-terminated liquid nitrile rubber, stabilizer, anti-ultraviolet agent and color paste, placing them in a high-speed disperser and stirring and mixing them evenly, and adding an inorganic foaming agent, stirring for 40 minutes to mix and then slurrying to obtain a PVC foam layer slurry;

[0142] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2, coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0143] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0144] Comparative Example 1

[0145] The only difference between this embodiment and embodiment 1 is that the amount of low-temperature resistant plasticizer in the raw material for preparing the PVC skin layer is 20 g.

[0146] Comparative Example 2

[0147] The only difference between this embodiment and embodiment 1 is that the amount of low- and high-temperature resistant plasticizer in the raw material for preparing the PVC skin layer is 60 g.

[0148] Comparative Example 3

[0149] The only difference between this embodiment and embodiment 1 is that the plasticizer in the raw material for preparing the PVC skin layer is DOP plasticizer.

[0150] Comparative Example 4

[0151] The only difference between this embodiment and embodiment 1 is that the toughening agent in the raw material for preparing the PVC skin layer is EVA741 toughening agent.

[0152] Comparative Example 5

[0153] The only difference between this embodiment and embodiment 1 is that the raw materials for preparing the super durable PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low and high temperature resistant plasticizer, and 6g of inorganic foaming agent.

[0154] Comparative Example 6

[0155] The only difference between this embodiment and embodiment 1 is that the amount of the inorganic foaming agent is 3 g.

[0156] Comparative Example 7

[0157] The only difference between this embodiment and embodiment 1 is that the amount of the inorganic foaming agent is 15 g.

[0158] Comparative Example 8

[0159] The only difference between this embodiment and embodiment 1 is that the type of foaming agent is a microsphere foaming agent.

[0160] Comparative Example 9

[0161] The only difference between this embodiment and embodiment 1 is that the foaming agent is an organic foaming agent.

[0162] Comparative Example 10

[0163] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0164] The raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 20g of low-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0165] The raw materials for preparing the PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low-temperature and high-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 6g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0166] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0167] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0168] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0169] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0170] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0171] Comparative Example 11

[0172] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0173] The raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 60g of low-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 3g of modified wood cellulose, and 0.1g of modified nano-silica; wherein the modified wood cellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0174] The raw materials for preparing the PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low-temperature and high-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 6g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0175] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0176] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0177] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0178] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0179] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0180] Comparative Example 12

[0181] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0182] The raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 20g of DOP plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0183] The raw materials for preparing the PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low-temperature and high-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 6g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0184] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0185] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0186] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0187] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0188] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0189] Comparative Example 13

[0190] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0191] The raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 20g of DOP plasticizer, 3g of EVA 741 toughening agent, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0192] The raw materials for preparing the PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low-temperature and high-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 6g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0193] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0194] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0195] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0196] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0197] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0198] Comparative Example 14

[0199] Super durable PVC artificial leather, including base fabric layer, PVC foam layer and PVC surface layer;

[0200] The raw materials for preparing the PVC skin layer include: 85g of polyvinyl chloride resin, 20g of DOP plasticizer, 3g of modified lignocellulose, and 0.1g of modified nano-silica; wherein the modified lignocellulose is prepared according to Preparation Example 1, and the modified nano-silica is prepared according to Preparation Example 2;

[0201] The raw materials for preparing the PVC foam layer include: 85g of polyvinyl chloride resin, 30g of low-temperature and high-temperature resistant plasticizer, 3g of carboxyl-terminated liquid nitrile rubber, and 6g of inorganic foaming agent; wherein the inorganic foaming agent is prepared according to Preparation Example 4;

[0202] When preparing the PVC skin layer, polyvinyl chloride resin, low-temperature resistant plasticizer, modified wood cellulose and modified nano-silica are accurately weighed, stirred and mixed evenly, and then carboxyl-terminated liquid nitrile rubber is added. The mixture is stirred for 80 minutes and vacuumed. The vacuum degree is maintained at 0.08 MPa for 10 minutes, and the mixture is stirred at 15°C for 10 minutes to obtain a PVC skin layer slurry.

[0203] Apply the PVC surface layer slurry to the release paper by scraper or coating method, with a coating amount of 15-30g / m 2 , coating speed is 20m / min; drying at 180℃ to obtain PVC surface layer;

[0204] Then, a PVC foam layer was prepared by accurately weighing polyvinyl chloride resin, low-temperature resistant plasticizer, and carboxyl-terminated liquid nitrile rubber, placing them in a high-speed disperser and stirring and mixing them evenly, and then adding an inorganic foaming agent, stirring for 40 minutes to mix evenly and slurrying to obtain a PVC foam layer slurry;

[0205] Apply the PVC foaming layer slurry to the PVC surface layer by scraper or coating method, and the coating amount is 50-60g / m 2 , coating speed is 20m / min; drying at 200℃ to obtain PVC foam layer;

[0206] The adhesive is applied on the PVC foam layer and laminated to the base fabric, the drying temperature is 200° C., and then embossing is performed to obtain PVC artificial leather.

[0207] Performance testing

[0208] Heat and aging resistance test: According to Volkswagen VW50132 standard, the super durable PVC artificial leather is placed at 100℃ and 120℃ for 168 hours to test its heat and aging resistance. The evaluation levels are: Level 5 means strong heat and aging resistance; Level 4 means relatively strong heat and aging resistance; Level 3 means average heat and aging resistance; Level 2 means relatively poor heat and aging resistance; Level 1 means poor heat and aging resistance.

[0209] Low temperature and bending resistance test: According to ISO5402 standard, the bending resistance test is carried out at -10℃, and after being bent 20,000 times at -10℃, the bending resistance test is further carried out at -30℃. The lower the temperature, the more bending times and no change in the sample, the better the low temperature and bending resistance.

[0210] Low temperature flexibility test: According to Volkswagen PV3905 standard, a ball drop test is carried out at -30℃ for 22 hours. If the sample does not change, it indicates good low temperature flexibility.

[0211] Table 1 Evaluation results of heat resistance and aging resistance, low temperature flexibility and low temperature bending resistance

[0212]

[0213]

[0214] Referring to Table 1, compared with Comparative Examples 1 to 9, the super-durable PVC foam layers in Examples 1 to 3 exhibited better heat resistance and aging resistance, low-temperature flexibility, and low-temperature bending resistance, indicating the importance of low- and high-temperature resistant plasticizers, carboxyl-terminated liquid nitrile rubber toughening agents, and inorganic foaming agents. The present application uses a low- and high-temperature resistant plasticizer to improve the structural stability of the polyvinyl chloride resin, allowing the polyvinyl chloride resin to have both high-temperature resistance and low-temperature flexibility, thereby reducing the extraction of the plasticizer; at the same time, a carboxyl-terminated liquid nitrile rubber toughening agent is introduced to toughen the polyvinyl chloride resin, further improving the Tg of the polyvinyl chloride resin to optimize its folding resistance at a low temperature of -20°C, further improving the low- and high-temperature folding resistance of the polyvinyl chloride resin; and on this basis, an inorganic foaming agent is selected for foaming, which helps to repeatedly improve the folding resistance of the polyvinyl chloride resin, thereby achieving super-durable performance of PVC artificial leather.

[0215] With reference to Table 1, compared with Comparative Examples 1 to 5, in Examples 1 to 3 and 4 to 5, the amounts of the low-temperature plasticizer and the carboxyl-terminated liquid nitrile rubber toughening agent were adjusted, thereby changing the heat resistance and aging resistance, low-temperature flexibility, and low-temperature bending resistance of the PVC foam layer. According to Example 8, the model of the carboxyl-terminated liquid nitrile rubber toughening agent was selected from CN-10-I or CN-10-II, and the measurement results were not significantly affected.

[0216] Referring to Table 1, compared to Comparative Examples 6-9, the foaming agents selected in Examples 1-3 and Examples 6-7, prepared under different conditions, yield inorganic foaming agents with improved folding resistance, thereby further enhancing the folding resistance of the PVC foam layer and achieving ultra-durable PVC artificial leather. The inorganic material includes sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, or ammonium nitrite. The inorganic material is grafted onto the maleic anhydride grafted material using polar aldehyde groups and olefin non-polar segments, significantly improving the compatibility of the grafted inorganic material with the polyvinyl chloride resin and compensating for some of the shortcomings of microsphere foaming agents and organic foaming agents.

[0217] Table 2 Evaluation results of heat resistance and aging resistance, low temperature flexibility and low temperature bending resistance

[0218]

[0219]

[0220] Referring to Table 2, compared with Comparative Examples 10 to 14, the super-durable PVC artificial leather in Examples 9 to 11 exhibited better heat resistance and aging resistance, low-temperature flexibility, and low-temperature bending resistance, indicating the importance of low- and high-temperature resistant plasticizers, carboxyl-terminated liquid nitrile rubber toughening agents, and inorganic foaming agents in the PVC skin layer and the PVC foam layer. The present application uses a low- and high-temperature resistant plasticizer to improve the structural stability of the polyvinyl chloride resin, so that the polyvinyl chloride resin has both high-temperature resistance and low-temperature flexibility, thereby reducing the extraction of the plasticizer, making the polyvinyl chloride resin less susceptible to brittleness at low temperatures and less susceptible to decomposition at high temperatures, thereby improving the low- and high-temperature folding resistance of the polyvinyl chloride resin. At the same time, a carboxyl-terminated liquid nitrile rubber toughening agent is introduced to toughen the polyvinyl chloride resin, further improving the Tg of the polyvinyl chloride resin to optimize its folding resistance at a low temperature of -20°C, further improving the low- and high-temperature folding resistance of the polyvinyl chloride resin.

[0221] Referring to Table 2, the inorganic foaming agents used in Examples 9-11 can optimize the flexibility of their cell structures within the polyvinyl chloride resin, further enhancing the folding resistance of the PVC foam layer and ultimately achieving ultra-durability in the PVC artificial leather. This is because the thermoplastic shell of existing microsphere foaming agents has a greater plasticity than polyvinyl chloride, creating a potential stress concentration area during the foaming process, thereby reducing the folding resistance of the polyvinyl chloride resin. By using an inorganic foaming agent, the sustained stress fatigue caused by the microsphere foaming agent on the gelled PVC is optimized, and a foam-like structure is formed within the PVC material, ultimately forming the PVC foam layer.

[0222] Referring to Table 2, compared with Example 9, it can be seen that the PVC skin layer and the PVC foam layer in Example 12 increase the amount of the end-carboxyl liquid nitrile rubber toughening agent on the basis of determining the amount of the low- and high-temperature resistant plasticizer raw material. According to the measurement results, it can be obtained that the low-temperature resistance and bending resistance of the PVC artificial leather in this embodiment are improved to a certain extent, and at the same time, it can play a role in not reducing the high-temperature resistance of the polyvinyl chloride resin; at the same time, the PVC skin layer and the PVC foam layer in Example 13 increase the amount of the low- and high-temperature resistant plasticizer on the basis of determining the amount of the end-carboxyl liquid nitrile rubber toughening agent raw material. According to the measurement results, it can be obtained that the high-temperature resistance and low-temperature flexibility of the PVC artificial leather in this embodiment are improved to a certain extent, but the mechanical strength and hardness of the polyvinyl chloride resin may be reduced. However, due to the presence of modified wood cellulose and modified nano-silica, this defect can be compensated.

[0223] With reference to Table 2, compared with Examples 18-20, Examples 14-17 contribute to improving the heat-oxidative aging resistance, mechanical strength and antibacterial properties of PVC artificial leather by adding modified wood cellulose and modified nano-silica in the PVC epidermis. Wherein the lignin molecular structure contains a hindered phenol structure, which has a certain ability to capture free radicals and can effectively improve the heat-resistant and aging-resistant properties of fat. However, since natural fibers have strong hydrophilicity, the interface performance between them and hydrophobic resins is poor, and nano-silica also has strong hydrophilic and oleophobic properties, making it difficult to mix with wood cellulose. By modifying lignin and nano-silica, the modified lignin can improve its compatibility with polyvinyl chloride resin. At the same time, the nano-silica particles modified with silane coupling agents have dual reaction functional groups on their surface, which can react with wood cellulose and have good affinity with polyvinyl chloride resin. Thus, the compatibility between cellulose and polyvinyl chloride resin is increased through the bridge effect of silica, forming a better interface bond.

[0224] In combination with Example 9, Example 14-Example 16, according to the experimental measurement results, it can be obtained that the measurement results are best when the mass ratio of modified lignocellulose and modified nano-silica is 10: (0.5-1.5). This is because when the mass ratio of modified lignocellulose and modified nano-silica exceeds the range of 10: (0.5-1.5), the nanoparticles are prone to not taking effect due to too little or agglomeration due to too much, which leads to mediocre reaction activity and reduces the heat-oxidative aging resistance, mechanical strength and antibacterial properties of PVC artificial leather.

[0225] With reference to Table 2, in combination with Examples 9 and 21-22, it can be seen that adding additives such as stabilizers, anti-ultraviolet agents and color pastes in the preparation of PVC artificial leather can help the PVC artificial leather obtain better performance and more vivid colors.

[0226] Odor test: According to Volkswagen PV3900 standard, take 200cm 2 The samples were tested for their odor, with lower ratings indicating better odors; the evaluation scale was: 1 for unnoticeable odor; 2 for non-offensive odor; 3 for noticeable odor but still not offensive; 4 for offensive; 5 for very offensive; and 6 for unbearable.

[0227] Amine resistance test: Amine resistance is tested according to Volkswagen PV3944 standard.

[0228] Table 3 Odor test and amine resistance test

[0229]

[0230]

[0231] Referring to Table 3, compared with Comparative Examples 6-9, the odor levels and amine resistance in Examples 1 and 6-7 are higher than those of microsphere foaming agents and organic foaming agents. Among them, microsphere foaming agents are elastomeric microspheres. When the microspheres are heated, their volume will rapidly expand, and the VOC and odor of PVC leather products made with this type of foaming agent are very low. However, after comparative testing, our team of researchers found that the thermoplastic shell of the microsphere foaming agent is still relatively plastic compared to the plasticized PVC. During the folding fatigue test, these elastomeric microspheres become potential stress concentration areas and continuously accumulate stress and strain on the PVC product. Therefore, combined with the measurement results in Table 1, it can be seen that the folding resistance of PVC leather products foamed by microsphere foaming agents will be lower than that of traditional organic foaming agents. However, the product odor and VOC of organic foaming agents are poor. Therefore, by selecting inorganic foaming agents, the continuous stress fatigue caused by microsphere foaming agents on gelled PVC can be optimized, and amine residues, odor and VOC can be optimized at the same time.

[0232] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. Super durable PVC artificial leather, characterized in that, Including super durable PVC foam layer and PVC skin layer, The PVC skin layer comprises the following components by weight: 85-100 parts by weight of polyvinyl chloride resin, 30-50 parts by weight of a low-temperature resistant plasticizer, 3-20 parts by weight of carboxyl-terminated liquid nitrile rubber, 3-8 parts by weight of a stabilizer, 3-15 parts by weight of modified wood cellulose, and 0.1-3 parts by weight of modified nano-silica; the wood cellulose and nano-silica are modified with a silane coupling agent; The PVC foam layer comprises the following components by weight: 85-100 parts by weight of polyvinyl chloride resin, 30-50 parts by weight of low-temperature resistant plasticizer, 3-20 parts by weight of carboxyl-terminated liquid nitrile rubber and 6-10 parts by weight of inorganic foaming agent; The low and high temperature resistant plasticizer was purchased from Kunrui Chemical, model number is DIPLAST L9-11; The carboxyl-terminated liquid nitrile rubber is selected from the carboxyl-terminated liquid nitrile rubber of model CN-10-I or CN-10-II; The inorganic foaming agent is specifically a mineral-based endothermic foaming agent, and its preparation steps are as follows: Grinding and sieving the inorganic material to obtain an inorganic material, then adding ethanol and maleic anhydride to mix and disperse, and reacting at 60° C. for 1-3 hours to obtain a mineral-based endothermic foaming agent; The inorganic substance is sodium bicarbonate; The weight ratio of the inorganic substance, ethanol and maleic anhydride is 1: (1.5-2.5): (0.1-0.2).

2. The super durable PVC artificial leather according to claim 1, characterized in that: The preparation of the modified lignocellulose is as follows: The lignocellulose and the silane coupling agent aqueous solution are mixed to prepare a mixed liquid, which is then evenly stirred, filtered and dried to obtain modified lignocellulose.

3. The super durable PVC artificial leather according to claim 1, characterized in that: The preparation of the modified nano-silica is as follows: The nano-silica is dried for 8-16 hours, and then anhydrous ethanol is added to prepare a nano-silica solution; the nano-silica solution is then mixed with a silane coupling agent aqueous solution, and dispersed at 60-100° C. to obtain a modified nano-silica solution, which is finally obtained by filtering and drying.

4. The method for preparing the super durable PVC artificial leather according to any one of claims 1 to 3, characterized in that: The following steps are involved: Prepare PVC skin layer slurry and PVC foam layer slurry according to the raw material ratio; apply the PVC skin layer slurry on the release paper, and dry and shape it to obtain the PVC skin layer; The PVC foam layer slurry is applied on the PVC surface layer, and the PVC foam layer is obtained after drying and forming; the PVC foam layer is then laminated to the base fabric to obtain the PVC artificial leather.

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