Environment-friendly high-elasticity artificial leather as well as preparation method and application thereof

Abstract

The invention relates to environment-friendly artificial leather as well as a preparation method and application thereof, and belongs to the field of high polymer materials. The artificial leather structure provided by the invention comprises a base cloth layer, a foaming layer and a surface layer which are sequentially laminated from inside to outside, the foaming layer is prepared from the following components in parts by weight: 100 parts of PVC (Polyvinyl Chloride) resin, 60 to 130 parts of aconite, 100 to 200 parts of filler, 3.5 to 8.0 parts of stabilizer and 8 to 16 parts of foaming agent; the surface layer is prepared from the following components in parts by weight: 65 to 75 parts of PVC (Polyvinyl Chloride) resin, 70 to 80 parts of aconite, 20 to 30 parts of filler and 1.5 to 4 parts of stabilizer. The artificial leather provided by the invention has better environmental protection property, elasticity and aging resistance, and the used aconite plasticizer has lower molecular weight and stronger molecular chain activity, and can effectively open chain entanglement of high-polymerization-degree PVC (Polyvinyl Chloride), thereby finally obtaining a high-elasticity PVC artificial leather product.

Description

Technical Field

[0001] The invention relates to an environmentally friendly high-elastic artificial leather and a preparation method thereof, and belongs to the field of polymer materials. Background Art

[0002] The rapid development of the automobile and home furnishing industries has led to a growing demand for artificial leather. Polyurethane artificial leather is widely used in sofa furniture and car interiors because of its good softness and realistic texture. In the artificial leather industry, most polyurethane artificial leathers are processed by wet rubbing process, but this process will cause the problem of hydrolysis of artificial leather. In addition, due to its high cost and the inability to produce coarse-grained products, the production and application ratio of domestic polyurethane artificial leather have declined every year since 2005. PVC artificial leather is gradually being widely used because of its low cost and perfect processing technology.

[0003] However, there are several urgent problems to be solved for PVC artificial leather products: First, a large amount of plasticizers need to be added when producing PVC artificial leather products. These plasticizers are volatile and will give PVC artificial leather products a certain unpleasant odor. In addition, some plasticizers are petroleum-based products, and long-term use will inevitably pose a threat to human health; second, ordinary PVC artificial leather has poor elasticity, and other additives need to be added to improve elasticity, which greatly increases production costs.

[0004] Chinese patent application CN119081309A discloses a polyvinyl chloride composition, its application in artificial leather scraping process and polyvinyl chloride artificial leather, which effectively improves the migration resistance and weather resistance of the product by selecting a specific polyvinyl chloride paste resin, a specific polyester plasticizer and a low molecular weight plasticizer. Chinese patent application CN116971186A discloses a method for preparing a bio-based PVC artificial leather, in which the plasticizer front-end raw material used is plant-based (non-food), and is prepared by chain extension alcohol, eliminating the high carbon footprint disadvantage of traditional plasticizers made of petroleum-based raw materials. However, none of these prior arts solve the above technical problems.

[0005] Based on the above problems existing in the artificial leather in the prior art, it is necessary to develop an environmentally friendly, highly elastic PVC artificial leather product. Summary of the invention

[0006] In order to solve the above problems, the present invention provides an environmentally friendly high-elastic artificial leather and a preparation method thereof. The PVC artificial leather has high elasticity, high water resistance and a high foaming agent expansion rate. The product is also green and environmentally friendly and will not affect human health after use. The processing method of the PVC artificial leather is simple and easy and is suitable for large-scale industrial production.

[0007] The first aspect of the present invention provides an environmentally friendly high-elastic artificial leather, which comprises a base fabric layer, a foaming layer and a skin layer which are sequentially laminated from the inside to the outside; the foaming layer comprises the following components in parts by weight: 100 parts of PVC resin, 60-130 parts of aconitate, 100-200 parts of filler, 3.5-8.0 parts of stabilizer, and 8-16 parts of foaming agent; the skin layer comprises the following components in parts by weight: 65-75 parts of PVC resin, 70-80 parts of aconitate, 20-30 parts of filler, and 1.5-4 parts of stabilizer.

[0008] Optionally, the degree of polymerization of the PVC resin is 1800-2000.

[0009] Optionally, the aconitate ester is selected from one or more of tri-n-butyl aconitate, tri-n-pentyl aconitate, tri-n-hexyl aconitate, tri-n-heptyl aconitate, tri-n-octyl aconitate, and tri(2-ethylhexyl) aconitate.

[0010] Optionally, the filler is one or more of heavy calcium carbonate, nano calcium carbonate, talcum powder, and mica powder.

[0011] Optionally, the stabilizer is one or more of a barium zinc stabilizer, a calcium zinc composite stabilizer, methyl tin mercaptan, and antimony epoxy ester.

[0012] Optionally, the foaming agent is an azo foaming agent.

[0013] The second aspect of the present invention provides a method for preparing the environmentally friendly high-elastic artificial leather as described above, wherein the steps of preparing the environmentally friendly high-elastic artificial leather include:

[0014] (1) Mixing and mixing the foaming layer components and the skin layer components according to the weight ratio;

[0015] (2) Mixing and kneading: The weighed foaming layer components and the skin components are mixed and kneaded respectively, and the banburying temperature is set at 110-130° C., the banburying time is 5-9 min, and the open kneading temperature is set at 120-140° C., and the open kneading time is 5-8 min;

[0016] (3) Calendering and laminating: the foaming layer component and the skin layer component are respectively added to a four-roll calender for calendering to obtain a foaming layer and a skin layer; the foaming layer and the skin layer are then laminated by a laminating machine, and then the foaming layer and the base fabric material are laminated to obtain a semi-finished artificial leather; the front roller temperature of the four-roll calender is set to 160-185°C, the upper roller temperature of the four-roll calender is set to 170-200°C, the middle roller temperature of the four-roll calender is set to 120-150°C, and the lower roller temperature of the four-roll calender is set to 110-140°C; the laminating pressure of the laminating machine is set to 25-35kg / cm2 , set the laminating temperature of the foaming layer and the skin layer to 210-240°C;

[0017] (4) Cooling: Cooling the semi-finished artificial leather under cold air at 0-10°C;

[0018] (5) Foaming: The semi-finished artificial leather is transferred to a foaming machine for foaming; the foaming temperature is set at 150 to 170° C. and the foaming time is 3 to 4 minutes;

[0019] (6) Surface treatment: coating the surface of the epidermis with a water-based surface treatment agent for surface treatment at a temperature of 120 to 135° C. and a treatment speed of 10 to 15 m / min;

[0020] (7) Embossing, cooling and rolling: The semi-finished artificial leather after surface treatment is subjected to surface embossing, cooling and rolling to obtain PVC artificial leather, i.e., the environmentally friendly high-elastic artificial leather finished product.

[0021] Optionally, the aqueous surface treatment agent comprises the following components in parts by weight: 80 to 100 parts of hydrophilic aliphatic polyisocyanate and 0 to 0.2 parts of free isocyanate.

[0022] The third aspect of the present invention provides an application of the artificial leather as described above, wherein the environmentally friendly high-elastic artificial leather is applied to automobile interior decoration, household goods surface covering materials, shoe upper materials or sporting goods surface covering materials.

[0023] Beneficial effects:

[0024] The present invention provides an environmentally friendly high-elastic artificial leather and a preparation method and application thereof, and the beneficial effects include but are not limited to:

[0025] 1. The aconitate plasticizer used in the environmentally friendly high-elastic artificial leather of the present invention is a bio-based product, which is more environmentally friendly than phthalate plasticizers and will not have adverse effects on human health after use.

[0026] 2. The environmentally friendly high-elastic artificial leather of the present invention has high elasticity. The polymerization degree of PVC used in PVC artificial leather on the market is generally between 1250 and 1300. This type of PVC polymerization degree is relatively low, so it is impossible to ensure that the artificial leather has high elasticity; and elasticity is a characteristic that artificial leather needs to have. The higher the elasticity of the artificial leather, the higher the comfort and durability of the product. However, the current method for increasing the elasticity of artificial leather products mainly adds more plasticizers or other additives, which will greatly increase the production cost. On the other hand, the higher the polymerization degree of PVC, the higher the elasticity will be. However, at present, artificial leather products with high polymerization degree have not yet formed a scale. The reason is that the higher the polymerization degree, the higher the chain entanglement degree of PVC, so that ordinary plasticizers are more difficult to open the chain entanglement of PVC, and it is difficult to obtain a low-cost artificial leather product with high elasticity. The aconitate plasticizer used in the present invention has a lower molecular weight and a stronger molecular chain activity, which is conducive to the rapid entry of aconitate into the interior of the PVC molecular chain and opening the chain entanglement, so that the effective plasticization of high-polymerization PVC is achieved, and finally a low-cost high-elasticity PVC artificial leather is obtained.

[0027] 3. The environmentally friendly high-elastic artificial leather of the present invention has high elasticity and high foaming agent expansion rate. Compared with conventional plasticizers (such as epoxidized soybean oil), the aconitate plasticizer used in the present invention is effectively compatible with PVC, so it can achieve efficient plasticization of PVC. On this basis, the fluidity of the PVC matrix is ​​better, which is more conducive to the effective dispersion of the foaming agent and filler in the system. Therefore, the foaming agent foams evenly in the system and the foaming rate is also higher; the filler is also easier to achieve the reinforcement of PVC.

[0028] 4. The environmentally friendly high-elastic artificial leather according to the present invention has high aging resistance. Compared with citrate, aconitate lacks an exposed hydroxyl group in its molecular structure. The hydroxyl group has higher reactivity and is prone to oxidation reaction. Therefore, the artificial leather product plasticized with aconitate has relatively higher aging resistance and wear resistance. DETAILED DESCRIPTION

[0029] The present invention is described in detail below with reference to the examples, but the present invention is not limited to these examples. Unless otherwise specified, the raw materials used in the examples and comparative examples of the present invention can be obtained through commercial channels.

[0030] In the embodiment of the present invention, PVC resin is purchased from Xinjiang Tianye (Group) Co., Ltd., with the brands: TY-1800 (degree of polymerization is 1800), TY-1900 (degree of polymerization is 1900), and TY-2000 (degree of polymerization is 2000); heavy calcium carbonate is purchased from Shanghai Nuocheng Pharmaceutical Co., Ltd., with the brand: heavy calcium carbonate (GCC); nano calcium carbonate is purchased from Guangxi Warner New Materials Technology Co., Ltd., with the brand: nano calcium carbonate; talcum powder is purchased from Guangdong Nao New Materials Technology Co., Ltd., with the brand: Yimifabi hm4HTP2L; methyl tin mercaptan was purchased from Foshan Tianshengda Metal Materials Co., Ltd., brand: MT-181; calcium zinc stabilizer was purchased from Wenzhou Zhengbang Chemical Co., Ltd., brand: CZ-113W; barium zinc stabilizer was purchased from Shanghai Huayi Chemical Additives Co., Ltd., brand: HY-801; zinc stearate was purchased from Shandong Qiangsen Chemical Co., Ltd., brand: ZS-90; AC foaming agent was purchased from Jinyang Company of South Korea, brand: CELLCOMAC-1000; hydrophilic aliphatic polyisocyanate was purchased from Wanhua Chemical, brand: HT-100, free isocyanate purchased from Wanhua Chemical, brand: MDI-50.

[0031] Example 1

[0032] The present embodiment provides an environmentally friendly high-elastic artificial leather and a preparation method thereof. The environmentally friendly high-elastic artificial leather comprises a base fabric layer, a foaming layer and a skin layer which are sequentially laminated from the inside to the outside; the foaming layer comprises the following components in parts by weight: 100 parts of PVC resin, 80 parts of aconitate, 140 parts of filler, 5 parts of stabilizer, and 12 parts of foaming agent; the skin layer comprises the following components in parts by weight: 70 parts of PVC resin, 75 parts of aconitate, 25 parts of filler, and 2.5 parts of stabilizer.

[0033] The polymerization degree of the PVC resin is 1900, the filler is heavy calcium carbonate, the aconitate ester is tri-n-butyl aconitate, the stabilizer is methyl tin mercaptan, and the foaming agent is azo foaming agent AC.

[0034] The preparation steps of the environmentally friendly high-elastic artificial leather include:

[0035] (1) Mixing and mixing the foaming layer components and the skin layer components according to the weight ratio;

[0036] (2) Mixing and kneading: The weighed foaming layer components and the skin components are mixed and kneaded respectively, and the banburying temperature is set to 120° C., the banburying time is 7 min, and the open kneading temperature is set to 130° C., and the open kneading time is 7 min;

[0037] (3) Calendering and laminating: the foaming layer component and the skin layer component are respectively added to a four-roll calender for calendering to obtain a foaming layer and a skin layer; then the foaming layer and the skin layer are laminated by a laminating machine, and then the foaming layer and the base fabric material are laminated to obtain a semi-finished artificial leather; the front roller temperature of the four-roll calender is set to 170°C, the upper roller temperature of the four-roll calender is set to 180°C, the middle roller temperature of the four-roll calender is set to 135°C, and the lower roller temperature of the four-roll calender is set to 130°C; the laminating pressure of the laminating machine is set to 30kg / cm 2 , set the laminating temperature of the foaming layer and the skin layer to 230°C;

[0038] (4) Cooling: Cool the semi-finished artificial leather under cold air at 5°C;

[0039] (5) Foaming: The semi-finished artificial leather is transferred to a foaming machine for foaming; the foaming temperature is set to 160° C. and the foaming time is set to 4 min;

[0040] (6) Surface treatment: coating the surface of the epidermis with a water-based surface treatment agent for surface treatment at a temperature of 130° C. and a treatment speed of 12 m / min;

[0041] (7) Embossing, cooling and rolling: The semi-finished artificial leather after surface treatment is subjected to surface embossing, cooling and rolling to obtain PVC artificial leather, i.e., the environmentally friendly high-elastic artificial leather finished product.

[0042] Wherein, the aqueous surface treatment agent in step (6) comprises the following components in parts by weight: 90 parts of hydrophilic aliphatic polyisocyanate and 0.2 parts of free isocyanate.

[0043] Example 2

[0044] The present embodiment provides an environmentally friendly high-elastic artificial leather and a preparation method thereof. The environmentally friendly high-elastic artificial leather comprises a base fabric layer, a foaming layer and a skin layer which are sequentially laminated from the inside to the outside; the foaming layer comprises the following components in parts by weight: 100 parts of PVC resin, 60 parts of aconitate, 100 parts of filler, 3.5 parts of stabilizer, and 8 parts of foaming agent; the skin layer comprises the following components in parts by weight: 65 parts of PVC resin, 70 parts of aconitate, 20 parts of filler, and 1.5 parts of stabilizer.

[0045] The polymerization degree of PVC is 1900, the filler is nano calcium carbonate, the aconitate ester is tri-n-butyl aconitate, the stabilizer is calcium zinc stabilizer, and the foaming agent is azo foaming agent AC.

[0046] The preparation steps of the environmentally friendly high-elastic material include:

[0047] (1) Mixing and mixing the foaming layer components and the skin layer components according to the weight ratio;

[0048] (2) Mixing and kneading: The weighed foaming layer components and the skin components are mixed and kneaded respectively, and the banburying temperature is set to 110° C., the banburying time is 5 min, and the open kneading temperature is set to 120° C., and the open kneading time is 5 min;

[0049] (3) Calendering and laminating: the foaming layer component and the skin layer component are respectively added to a four-roll calender for calendering to obtain a foaming layer and a skin layer; the foaming layer and the skin layer are then laminated by a laminating machine, and then the foaming layer and the base fabric material are laminated to obtain a semi-finished artificial leather; the front roller temperature of the four-roll calender is set to 160°C, the upper roller temperature of the four-roll calender is set to 170°C, the middle roller temperature of the four-roll calender is set to 120°C, and the lower roller temperature of the four-roll calender is set to 110°C; the laminating pressure of the laminating machine is set to 25kg / cm 2 , set the laminating temperature of the foaming layer and the skin layer to 210°C;

[0050] (4) Cooling: Cooling the semi-finished artificial leather under cold air at 0°C;

[0051] (5) Foaming: transferring the semi-finished artificial leather to a foaming machine for foaming; setting the foaming temperature to 150° C. and the foaming time to 3 min;

[0052] (6) Surface treatment: coating the surface of the epidermis with a water-based surface treatment agent for surface treatment at a temperature of 120° C. and a treatment speed of 10 m / min;

[0053] (7) Embossing, cooling and rolling: The semi-finished artificial leather after surface treatment is subjected to surface embossing, cooling and rolling to obtain PVC artificial leather, i.e., the environmentally friendly high-elastic artificial leather finished product.

[0054] The aqueous surface treatment agent comprises the following components in parts by weight: 90 parts of hydrophilic aliphatic polyisocyanate and 0.2 parts of free isocyanate.

[0055] Example 3

[0056] The embodiment provides an environmentally friendly high-elastic artificial leather and a preparation method thereof. The environmentally friendly high-elastic artificial leather includes a base fabric layer, a foaming layer and a skin layer which are sequentially bonded from the inside to the outside; the foaming layer includes the following components in parts by weight: 100 parts of PVC resin, 130 parts of aconitate, 200 parts of filler, 8 parts of stabilizer, and 16 parts of foaming agent; the skin layer includes the following components in parts by weight: 75 parts of PVC resin, 80 parts of aconitate, 30 parts of filler, and 4 parts of stabilizer.

[0057] The polymerization degree of the PVC resin is 1900, the filler is talcum powder, the aconitate ester is tri-n-butyl aconitate, the stabilizer is barium zinc stabilizer, and the foaming agent is azo foaming agent AC.

[0058] The preparation steps of the environmentally friendly high-elastic artificial leather include:

[0059] (1) Mixing and mixing the foaming layer components and the skin layer components according to the weight ratio;

[0060] (2) Mixing and kneading: The weighed foaming layer components and the skin components are mixed and kneaded respectively, and the banburying temperature is set to 130° C., the banburying time is set to 9 min, and the open kneading temperature is set to 140° C., and the open kneading time is set to 8 min;

[0061] (3) Calendering and laminating: the foaming layer component and the skin layer component are respectively added to a four-roll calender for calendering to obtain a foaming layer and a skin layer; the foaming layer and the skin layer are then laminated by a laminating machine, and then the foaming layer and the base fabric material are laminated to obtain a semi-finished artificial leather; the front roller temperature of the four-roll calender is set to 185°C, the upper roller temperature of the four-roll calender is set to 200°C, the middle roller temperature of the four-roll calender is set to 150°C, and the lower roller temperature of the four-roll calender is set to 140°C; the laminating pressure of the laminating machine is set to 35kg / cm 2 , set the laminating temperature of the foaming layer and the skin layer to 240°C;

[0062] (4) Cooling: Cool the semi-finished artificial leather under cold air at 10°C;

[0063] (5) Foaming: The semi-finished artificial leather is transferred to a foaming machine for foaming; the foaming temperature is set to 170° C. and the foaming time is set to 5 min;

[0064] (6) Surface treatment: coating the surface of the epidermis with a water-based surface treatment agent for surface treatment at a temperature of 135° C. and a treatment speed of 15 m / min;

[0065] (7) Embossing, cooling and rolling: The semi-finished artificial leather after surface treatment is subjected to surface embossing, cooling and rolling to obtain PVC artificial leather, i.e., the environmentally friendly high-elastic artificial leather finished product.

[0066] The aqueous surface treatment agent comprises the following components in parts by weight: 90 parts of hydrophilic aliphatic polyisocyanate and 0.2 parts of free isocyanate.

[0067] Example 4

[0068] The specific implementation methods of this embodiment are basically the same as those of Embodiment 1, except that the plasticizer is tri-n-hexyl aconitate.

[0069] Example 5

[0070] The specific implementation methods of this embodiment are basically the same as those of Embodiment 1, except that the plasticizer is tri-n-octyl aconitate.

[0071] Example 6

[0072] The specific implementation methods of this embodiment are basically the same as those of Embodiment 1, except that the degree of polymerization of the PVC resin is 1800.

[0073] Example 7

[0074] The specific implementation methods of this embodiment are basically the same as those of Embodiment 1, except that the degree of polymerization of the PVC resin is 2000.

[0075] Example 8

[0076] The specific implementation methods of this embodiment are basically the same as those of Embodiment 1, except that the aqueous surface treatment agent comprises the following components in parts by weight: 80 parts of hydrophilic aliphatic polyisocyanate and 0.1 parts of free isocyanate.

[0077] Example 9

[0078] The specific implementation methods of this embodiment are basically the same as those of Embodiment 1, except that the aqueous surface treatment agent comprises the following components in parts by weight: 100 parts of hydrophilic aliphatic polyisocyanate and 0.2 parts of free isocyanate.

[0079] Comparative Example 1

[0080] The present comparative example provides an artificial leather and a preparation method thereof. The artificial leather comprises a base fabric layer, a foaming layer and a skin layer which are sequentially laminated from the inside to the outside; the foaming layer comprises the following components in parts by weight: 100 parts of PVC resin, 40 parts of aconitate, 80 parts of filler, 1 part of stabilizer and 2 parts of foaming agent; the skin layer comprises the following components in parts by weight: 40 parts of PVC resin, 50 parts of aconitate, 10 parts of filler and 0.5 parts of stabilizer.

[0081] The polymerization degree of the PVC resin is 1900, the filler is heavy calcium carbonate, the aconitate ester is tri-n-butyl aconitate, the stabilizer is methyl tin mercaptan, and the foaming agent is azo foaming agent AC.

[0082] The preparation steps of the artificial leather include:

[0083] (1) Mixing and mixing the foaming layer components and the skin layer components according to the weight ratio;

[0084] (2) Mixing and kneading: The weighed foaming layer components and the skin components are mixed and kneaded respectively, and the kneading temperature is set to 80°C, the kneading time is 1 min, and the kneading temperature is set to 100°C, and the kneading time is set to 1 min;

[0085] (3) Calendering and laminating: the foaming layer component and the skin layer component are respectively added to a four-roll calender for calendering to obtain a foaming layer and a skin layer; the foaming layer and the skin layer are then laminated by a laminating machine, and then the foaming layer and the base fabric material are laminated to obtain a semi-finished artificial leather; the front roller temperature of the four-roll calender is set to 120°C, the upper roller temperature of the four-roll calender is set to 130°C, the middle roller temperature of the four-roll calender is set to 100°C, and the lower roller temperature of the four-roll calender is set to 90°C; the laminating pressure of the laminating machine is set to 15kg / cm 2 , set the laminating temperature of the foaming layer and the skin layer to 180°C;

[0086] (4) Cooling: Cooling the semi-finished artificial leather under cold air at 0°C;

[0087] (5) Foaming: The semi-finished artificial leather is transferred to a foaming machine for foaming; the foaming temperature is set to 120° C. and the foaming time is set to 1 min;

[0088] (6) Surface treatment: coating the surface of the epidermis with a water-based surface treatment agent for surface treatment at a temperature of 100° C. and a treatment speed of 5 m / min;

[0089] (7) Embossing, cooling and rolling: The semi-finished artificial leather after surface treatment is subjected to surface embossing, cooling and rolling to obtain a finished PVC artificial leather.

[0090] The aqueous surface treatment agent comprises the following components in parts by weight: 90 parts of hydrophilic aliphatic polyisocyanate and 0.2 parts of free isocyanate.

[0091] Comparative Example 2

[0092] The present comparative example provides an artificial leather and a preparation method thereof. The artificial leather comprises a base fabric layer, a foaming layer and a skin layer which are sequentially laminated from the inside to the outside; the foaming layer comprises the following components in parts by weight: 100 parts of PVC resin, 150 parts of aconitate, 240 parts of filler, 12.0 parts of stabilizer and 20 parts of foaming agent; the skin layer comprises the following components in parts by weight: 100 parts of PVC resin, 100 parts of aconitate, 50 parts of filler and 8 parts of stabilizer.

[0093] The polymerization degree of the PVC resin is 1900, the filler is heavy calcium carbonate, the aconitate ester is tri-n-butyl aconitate, the stabilizer is methyl tin mercaptan, and the foaming agent is azo foaming agent AC.

[0094] The preparation process of the artificial leather comprises the following steps:

[0095] (1) Mixing and mixing the foaming layer components and the skin layer components according to the weight ratio;

[0096] (2) Mixing and kneading: The weighed foaming layer components and the skin components are mixed and kneaded respectively, and the banburying temperature is set to 150° C., the banburying time is set to 15 min, and the open kneading temperature is set to 160° C., and the open kneading time is set to 12 min;

[0097] (3) Calendering and laminating: the foaming layer component and the skin layer component are respectively added to a four-roll calender for calendering to obtain a foaming layer and a skin layer; the foaming layer and the skin layer are then laminated by a laminating machine, and then the foaming layer and the base fabric material are laminated to obtain a semi-finished artificial leather; the front roller temperature of the four-roll calender is set to 210°C, the upper roller temperature of the four-roll calender is set to 230°C, the middle roller temperature of the four-roll calender is set to 180°C, and the lower roller temperature of the four-roll calender is set to 170°C; the laminating pressure of the laminating machine is set to 50kg / cm 2 , set the laminating temperature of the foaming layer and the skin layer to 270°C;

[0098] (4) Cooling: Cool the semi-finished artificial leather under cold air at 15°C;

[0099] (5) Foaming: The semi-finished artificial leather is transferred to a foaming machine for foaming; the foaming temperature is set to 190° C. and the foaming time is set to 10 min;

[0100] (6) Surface treatment: coating the surface of the epidermis with a water-based surface treatment agent for surface treatment at a temperature of 160° C. and a treatment speed of 20 m / min;

[0101] (7) Embossing, cooling and rolling: The semi-finished artificial leather after surface treatment is subjected to surface embossing, cooling and rolling to obtain a finished PVC artificial leather.

[0102] The aqueous surface treatment agent comprises the following components in parts by weight: 90 parts of hydrophilic aliphatic polyisocyanate and 0.2 parts of free isocyanate.

[0103] Comparative Example 3

[0104] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the plasticizer is replaced by tri-n-methyl aconitate.

[0105] Comparative Example 4

[0106] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the plasticizer is replaced by tri-n-decyl aconitate.

[0107] Comparative Example 5

[0108] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the degree of polymerization of the PVC resin is 1600 (purchased from Xinjiang Tianye (Group) Co., Ltd., brand: TY-1600).

[0109] Comparative Example 6

[0110] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the degree of polymerization of the PVC resin is 2400 (purchased from Xinjiang Tianye (Group) Co., Ltd., brand: TYH-2500).

[0111] Comparative Example 7

[0112] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the plasticizer is replaced by an equal amount of dibutyl phthalate.

[0113] Comparative Example 8

[0114] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the plasticizer is replaced by an equal amount of epoxidized soybean oil (purchased from Shenzhen Jinze Wanchang Petrochemical Co., Ltd., brand: ESO6).

[0115] Comparative Example 9

[0116] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the plasticizer is replaced by an equal amount of tri-n-butyl citrate.

[0117] Comparative Example 10

[0118] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the aqueous surface treatment agent contains the following components in parts by weight: 60 parts of hydrophilic aliphatic polyisocyanate and 0.3 parts of free isocyanate.

[0119] Comparative Example 11

[0120] The specific implementation methods of this comparative example and Example 1 are basically the same, except that the aqueous surface treatment agent contains the following components in parts by weight: 120 parts of hydrophilic aliphatic polyisocyanate and 0.5 parts of free isocyanate.

[0121] Comparative Example 12

[0122] The specific implementation manner of this comparative example is the same as that of Example 1, except that the foaming agent is replaced with a polyurethane foaming agent (purchased from Zibo Aohong Chemical Technology Co., Ltd., brand HFC-245fa).

[0123] Performance Testing

[0124] 1. Mechanical properties test

[0125] Mechanical properties tests were performed on the artificial leather prepared in the examples and comparative examples. The warp and weft tensile loads of the samples were measured according to GB / T38612-2020, and the test was performed with reference to the spline method. The sample size was: 3 pieces were cut from the edge of the sample more than 100 mm along the warp / longitudinal direction and the weft / transverse direction, and the sample size was (200±2) mm in length and (30±1) mm in width. Defects such as defects, marks, and stains should be avoided during cutting.

[0126] Test method:

[0127] 1) Set the fixture spacing to (100±1) mm and the constant elongation rate to (200±20) mm / min.

[0128] 2) Two clamps are clamped at both ends of the length direction of the sample to ensure that the center line of the tension passes through the midpoint of the clamp. Marking lines are drawn at both ends of the initial distance between the clamps. The sample can be clamped under pre-tension to ensure that the elongation is no more than 2%.

[0129] 3) Turn on the tester and stretch the specimen until it breaks. Record the maximum force (unit: N) to the nearest 0.1N and the clamp spacing L (unit: mm) at break to the nearest 0.1mm.

[0130] Results: Record the maximum force value of each specimen in the longitudinal and transverse directions, i.e. the tensile load, in Newton (N), according to the formula % = (L 2 -L 0 )*100 / L 0 Calculate the elongation at break, where L 2 L is the distance between the clamps when the specimen is tensile fractured, in millimeters (mm); 0 is the original fixture spacing in millimeters (mm).

[0131] 2. Adhesion test

[0132] The adhesion of the sample was tested according to the standard GB 8808-88B method, with a width of 30.0±0.2mm, a length of 150mm, a test condition of 200±50mm / min, and an expected value of ≥25N.

[0133] 3. Plasticizer volatility test

[0134] The volatility of the plasticizers involved in the embodiments and comparative examples (such as aconitate, phthalate plasticizers, epoxidized soybean oil, and tri-n-butyl citrate) in PVC was tested to evaluate the volatility of different types of plasticizers. The test was conducted with reference to HG / T 4458-2012 "Determination of Plasticizer Loss - Activated Carbon Method" at a test temperature of 70°C and a test time of 24h.

[0135] 4. Foaming ratio test

[0136] The foaming rate of the sample is tested by the compression method. The sample is placed in a closed container and then compressed with a compressor. The volume before and after compression is measured to calculate the foaming rate and the volume V of the artificial leather after compression is recorded. 2 , and the volume V of the artificial leather before compression 1 , Foaming ratio = V 1 / V 2 .

[0137] 5. Wear resistance test

[0138] The abrasion resistance of the samples was tested according to standard SS-EN ISO 5470-1, test conditions: 500g 2000r, expected value: gray scale ≥ 4 levels.

[0139] 6. Breaking permanent deformation test

[0140] The tensile permanent deformation properties of the test samples were tested according to GB / T 528-2009 at room temperature.

[0141] 7. Thermal aging test

[0142] According to GB / T 4043-2010 "Polyvinyl chloride artificial leather for automobiles" 6.24 thermal aging test, the discoloration level of the sample after thermal aging is tested.

[0143] 8. Shore A hardness test

[0144] The Shore A hardness of the artificial leather samples was tested using the Shore A hardness scale. The Shore A hardness can characterize the plasticizing efficiency of the plasticizer. The lower the Shore A hardness of the artificial leather after plasticization, the higher the plasticizing efficiency.

[0145] 9. Air permeability test

[0146] The air permeability of the samples was tested according to the method of QB / T 2799-2006.

[0147] The test results of the examples and comparative examples are shown in Table 1 and Table 2.

[0148] 10. Toxicology test

[0149] 1) According to GB 15193.5-2014 "National Food Safety Standard Mammalian Red Blood Cell Micronucleus Test", the genotoxicity of plasticizers is characterized by positive results, which indicate genotoxicity and negative results, which indicate non-genotoxicity. The test results show that when the plasticizer is aconitate, epoxidized soybean oil or tri-n-butyl citrate, the test results are all negative, indicating non-genotoxicity; while when the plasticizer is dibutyl phthalate (DBP), the test results are positive, indicating genotoxicity.

[0150] 2) According to GB / T 21853-2008 "Chemical Partition Coefficient (n-octanol-water) Shake Bottle Test" test characterizes the bioaccumulation of plasticizers. According to the standard of "Chemical Sediment Benthic Oligochaete Annelid Bioaccumulation Test", when its logPow>3, it is considered that the material has a certain bioaccumulation, and when its log Pow<3, the material has no bioaccumulation. The test found that when the plasticizer is tri-n-butyl aconitate, the log Pow of the sample is 2.95, when the plasticizer is tri-n-hexyl aconitate, the log Pow of the sample is 2.96, when the plasticizer is tri-n-methyl aconitate, the log Pow of the sample is 2.94, when the plasticizer is dibutyl phthalate, the log Pow of the sample is 4.47, when the plasticizer is epoxidized soybean oil, the log Pow of the sample is 2.98, and when the plasticizer is tri-n-butyl citrate, the log Pow of the sample is 2.97.

[0151] Table 1

[0152]

[0153]

[0154] Table 2

[0155]

[0156]

[0157] The data in Table 1 and Table 2 show that the PVC artificial leather in Examples 1 to 7 has good elasticity, foaming rate, wear resistance, and aging resistance, meeting the relevant performance requirements of PVC artificial leather; after adding the azo foaming agent, the foaming pore size is larger, giving the artificial leather excellent air permeability. The experimental results of Examples 1 to 3 and Comparative Examples 1 to 2 show that the proportions and preparation parameters of each component in the present invention must meet certain requirements. When they are lower or higher than a certain limit, the performance of the PVC artificial leather will be adversely affected, resulting in a poor plasticization effect of the PVC artificial leather, a hard texture, and poor comprehensive performance; or over-plasticization, the PVC artificial leather is soft in texture and has reduced elasticity. The experimental results of comparative examples 1, 4, 5 and comparative examples 3, 4 show that when the carbon number of the main chain of aconitate is 4 to 8, the plasticizing effect of aconitate is relatively good. At this time, the aconitate has a suitable molecular weight, and the molecular chain also has a high activity, which is more conducive to opening the chain entanglement of PVC, improving the plasticizing effect, and promoting the effective distribution of various additives such as reinforcing fillers and foaming agents in PVC, improving the reinforcing effect and foaming efficiency of the additives. When tri-n-methyl aconitate with a carbon number of less than 4 is used as a plasticizer, the molecular weight of tri-n-methyl aconitate is low, and it is very easy to be extracted from PVC, reducing the plasticizing effect, and at the same time causing the comprehensive performance of artificial leather to be reduced. When the number of carbon atoms in the main chain is greater than 8, the molecular weight of aconitate is relatively high. Although aconitate is difficult to extract from PVC at this time, the polarity of aconitate will also increase as the polar ester molecular chain becomes longer, resulting in poor compatibility with PVC. The plasticizing effect of aconitate on PVC will deteriorate, which will affect the adhesion, elasticity, wear resistance, aging resistance, air permeability, etc. of artificial leather. The experimental results of comparative examples 1, 6, 7 and comparative examples 5 and 6 show that the aconitate of the present invention can achieve a good plasticizing effect on PVC resin with a polymerization degree of 1800 to 2000, effectively open the chain entanglement, and ensure that the artificial leather has good elasticity. When the polymerization degree of PVC is lower than 1800, the plasticizing effect of aconitate is improved, but the elasticity of low molecular weight PVC is lower, so the elasticity of artificial leather at low molecular weight is also lower; when the polymerization degree of PVC is greater than 2000, because the chain entanglement of the PVC molecular chain is deeper, aconitate cannot plasticize it well, and the comprehensive performance of artificial leather including elasticity is reduced. The experimental results of Comparative Example 8 show that when the plasticizer is replaced with epoxy soybean oil, the plasticizing effect and foaming effect are reduced because the epoxy soybean oil has poor compatibility with PVC, and the performance of the obtained artificial leather product is deteriorated. The experimental results of Comparative Example 1 and Comparative Example 9 show that because tri-n-butyl citrate has an extra hydroxyl group in its structure, the hydroxyl group has higher reaction activity and is prone to oxidation reaction, so the artificial leather plasticized with tri-n-butyl citrate has low aging resistance and wear resistance.The experimental results of comparative examples 8 and 9 and comparative examples 10 and 11 show that the water-based surface treatment agent has an improving effect on the aging resistance and wear resistance of artificial leather, among which the main effect of the hydrophilic aliphatic polyisocyanate is to improve the aging resistance, and the free isocyanate mainly improves the wear resistance of artificial leather. When the addition ratio of the two is too high or too low, it will have a significant impact on the aging resistance and wear resistance of artificial leather; when the addition ratio is too high, the two components on the surface of the artificial leather will over-react, and the elasticity of the artificial leather will also decrease. The experimental results of comparative example 1 and comparative example 12 show that when the foaming agent is replaced with a polyurethane foaming agent, the air permeability of the obtained artificial leather is significantly reduced. The reason is that the average diameter of the bubbles of the polyurethane foaming agent is smaller than that of the AC foaming, and the vents are relatively reduced, so the air permeability of the artificial leather will be affected.

[0158] The results of toxicological tests show that aconitate plasticizers are green and environmentally friendly and have no effect on health compared to petroleum-based phthalate plasticizers. Compared with phthalate plasticizers, aconitate plasticizers also have better plasticizing effects.

[0159] The above description is only an embodiment of the present invention. The protection scope of the present invention is not limited by these specific embodiments, but is determined by the claims of the present invention. For those skilled in the art, the present invention may have various changes and variations. Any modification, equivalent substitution, improvement, etc. made within the technical ideas and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An environmentally friendly high-elastic artificial leather, characterized in that: The artificial leather comprises a base fabric layer, a foaming layer and a skin layer which are sequentially laminated from the inside to the outside; the foaming layer comprises the following components by weight: 100 parts of PVC resin, 60-130 parts of aconitate, 100-200 parts of filler, 3.5-8.0 parts of stabilizer, and 8-16 parts of foaming agent; the skin layer comprises the following components by weight: 65-75 parts of PVC resin, 70-80 parts of aconitate, 20-30 parts of filler, and 1.5-4 parts of stabilizer.

2. The environmentally friendly high-elastic artificial leather according to claim 1, characterized in that: The polymerization degree of the PVC resin is 1800-2000.

3. The environmentally friendly high-elastic artificial leather according to claim 1, characterized in that: The aconitate ester is selected from one or more of tri-n-butyl aconitate, tri-n-pentyl aconitate, tri-n-hexyl aconitate, tri-n-heptyl aconitate, tri-n-octyl aconitate, and tri(2-ethylhexyl) aconitate.

4. The environmentally friendly high-elastic artificial leather according to claim 1, characterized in that: The filler is one or more of heavy calcium carbonate, nano calcium carbonate, talcum powder and mica powder.

5. The environmentally friendly high-elastic artificial leather according to claim 1, characterized in that: The stabilizer is one or more of a barium zinc stabilizer, a calcium zinc composite stabilizer, methyl tin mercaptan, and an antimony epoxy ester.

6. The environmentally friendly high-elastic artificial leather according to claim 1, characterized in that: The foaming agent is an azo foaming agent.

7. A method for preparing the environmentally friendly high-elastic artificial leather according to any one of claims 1 to 6, characterized in that: The preparation steps of the environmentally friendly high-elastic artificial leather include: (1) Mixing and mixing the foaming layer components and the skin layer components according to the weight ratio; (2) Mixing and kneading: The weighed foaming layer components and the skin components are mixed and kneaded respectively, and the banburying temperature is set at 110-130° C., the banburying time is 5-9 min, and the open kneading temperature is set at 120-140° C., and the open kneading time is 5-8 min; (3) Calendering and laminating: The foaming layer component and the skin layer component are respectively added to a four-roll calender for calendering to obtain a foaming layer and a skin layer; then the foaming layer and the skin layer are laminated by a laminating machine, and then the foaming layer and the base fabric material are laminated to obtain a semi-finished artificial leather; (4) Cooling: Cooling the semi-finished artificial leather under cold air at 0-10°C; (5) Foaming: The semi-finished artificial leather is transferred to a foaming machine for foaming; the foaming temperature is set at 150 to 170° C. and the foaming time is 3 to 4 minutes; (6) Surface treatment: coating the surface of the epidermis with a water-based surface treatment agent for surface treatment at a temperature of 120 to 135° C. and a treatment speed of 10 to 15 m / min; (7) Embossing, cooling and rolling: The semi-finished artificial leather after surface treatment is subjected to surface embossing, cooling and rolling to obtain an environmentally friendly high-elastic artificial leather product.

8. The method for preparing the environmentally friendly high-elastic artificial leather according to claim 7, characterized in that: In the step (3), the temperature of the front roller of the four-roll calender is set to 160-185°C, the temperature of the upper roller of the four-roll calender is set to 170-200°C, the temperature of the middle roller of the four-roll calender is set to 120-150°C, and the temperature of the lower roller of the four-roll calender is set to 110-140°C; the laminating pressure of the laminating machine is set to 25-35kg / cm 2 The lamination temperature of the foaming layer and the skin layer is set to 210-240°C.

9. The method for preparing the environmentally friendly high-elastic artificial leather according to claim 7, characterized in that: The aqueous surface treatment agent comprises the following components in parts by weight: 80 to 100 parts of hydrophilic aliphatic polyisocyanate and 0 to 0.2 parts of free isocyanate.

10. An application of the environmentally friendly high-elastic artificial leather according to any one of claims 1 to 6, characterized in that: The environmentally friendly high-elastic artificial leather is applied to automobile interior decoration, household goods surface covering materials, shoe upper materials or sports goods surface covering materials.

Images