Repairable functional material, method for preparing the same, repairable artificial leather and method for preparing the same

Abstract

The application provides a repairable functional material, a preparation method thereof, a repairable artificial leather and a preparation method thereof, and relates to the technical field of artificial leather materials. Main preparation raw materials of the repairable functional material include: a thermoplastic elastomer matrix, a modified thermoplastic elastomer, a boron-containing compound and optional auxiliaries. The modified thermoplastic elastomer has a vicinal phenolic hydroxyl group on a molecular chain. The application introduces the modified thermoplastic elastomer with the vicinal phenolic hydroxyl group on the molecular chain, and cooperates with the boron-containing compound to construct a dynamic reversible borate ester bond network. The network can be quickly activated under moderate heating conditions, so that the material can be efficiently and in-situ repaired by means of daily household tools (such as an electric iron) after suffering from slight or moderate mechanical damage such as scratching and puncturing.

Description

Technical Field

[0001] This invention relates to the field of artificial leather materials technology, and in particular to a repairable functional material, its preparation method, repairable artificial leather and its preparation method. Background Technology

[0002] Currently, seat upholstery materials (widely used in automobiles, furniture and other fields) generally use genuine leather, PVC or PU synthetic leather. Although they have good aesthetics and feel, they are not very resistant to damage from sharp objects. Everyday contact with objects such as keys, pet paws, and stationery can easily cause permanent scratches, cracks or perforations.

[0003] Current solutions mainly involve passive acceptance or professional repair. The latter requires specialized filler paste, pigments, and spray guns, making the process cumbersome and costly. Furthermore, the repaired area often fails to match the original material in terms of color, texture, and durability. Commercially available self-healing materials, such as microencapsulation technology (which embeds repair agent capsules within the material, releasing the repair agent upon rupture) or reversible chemical cross-linked network materials, still have problems: excessive cost and demanding repair conditions (requiring specific light / temperature / long-term static placement), making rapid, low-cost repair impossible in everyday scenarios.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] One of the objectives of this invention is to provide a repairable functional material to at least solve one of the technical problems existing in the prior art.

[0006] The second objective of this invention is to provide a method for preparing a repairable functional material.

[0007] The third objective of this invention is to provide a repairable artificial leather.

[0008] The fourth objective of this invention is to provide a method for preparing repairable artificial leather.

[0009] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: In a first aspect, the present invention provides a repairable functional material, the main raw materials for which are prepared include: Thermoplastic elastomer matrix, modified thermoplastic elastomer, boron-containing compound and optional additives; The modified thermoplastic elastomer molecular chain contains ortho-phenolic hydroxyl groups.

[0010] Furthermore, the modified thermoplastic elastomer has the same main chain chemical structure as the thermoplastic elastomer matrix; Preferably, the thermoplastic elastomer matrix comprises one or more of styrene-ethylene-butene-styrene block copolymers, styrene-ethylene-propylene-styrene block copolymers, and styrene-butadiene-styrene block copolymers; Preferably, the modified thermoplastic elastomer is a thermoplastic elastomer obtained by modification with a compound containing dopamine structural units; Preferably, the compound containing the dopamine structural unit includes one or more of dopamine hydrochloride, dopamine, levodopa, and dopamine methacrylamide.

[0011] Furthermore, by weight, the main raw materials include: 100 parts by weight of the thermoplastic elastomer matrix and the modified thermoplastic elastomer, 2-6 parts by weight of boron-containing compound and 70.8-153 parts by weight of additives; Preferably, the boron-containing compound is present in the form of 2-5 parts; Preferably, the modified thermoplastic elastomer accounts for 10%-50% of the total weight of the thermoplastic elastomer matrix and the modified thermoplastic elastomer, and more preferably 15%-30%.

[0012] Furthermore, the boron-containing compound includes one or more of borax, trimethyl borate, and diboronate; Preferably, the additives include at least one of: plasticizer, tackifier, carrier resin, antioxidant and light stabilizer; Preferably, the plasticizer includes one or more of white mineral oil, paraffin oil, and dioctyl sebacate; Preferably, the tackifier comprises one or more of hydrogenated petroleum resin, DCPD petroleum resin, and hydrogenated rosin resin; Preferably, the carrier resin comprises one or more of polypropylene, low-density polyethylene, and ethylene-vinyl acetate copolymer; Preferably, the antioxidant includes one or more of hindered phenolic antioxidants and phosphite antioxidants; Preferably, the light stabilizer includes a hindered amine light stabilizer; Preferably, the additives include: 35-85 parts plasticizer, 15-45 parts tackifier, 5-35 parts carrier resin, 0.5-2 parts antioxidant, and 0.3-1 part light stabilizer; More preferably, the additives include: 40-80 parts plasticizer, 20-40 parts tackifier, 10-30 parts carrier resin, 0.5-2 parts antioxidant and 0.3-1 part light stabilizer.

[0013] Secondly, the present invention provides a method for preparing a repairable functional material, comprising: (a) A premix is ​​prepared by premixing a thermoplastic elastomer matrix, a modified thermoplastic elastomer, a boron-containing compound, and optional additives. (b) The premixed material is melt-blended and granulated to obtain the repairable functional material.

[0014] Furthermore, the premixing time is 3-10 minutes, and the rotation speed during the premixing process is 300-800 rpm; Preferably, the melt blending temperature is 160-200℃; Preferably, the modified thermoplastic elastomer is prepared by the following method: The modified thermoplastic elastomer is obtained by dissolving and mixing a thermoplastic elastomer, a compound containing dopamine structural units, and an organic solvent, and reacting them at room temperature under alkaline conditions. Preferably, the pH value of the alkaline conditions is 8.0-9.0, and the reaction time is 12-24 hours.

[0015] Thirdly, the present invention provides a repairable artificial leather, comprising: a repairable functional layer, and a base layer laminated to the back of the repairable functional layer; The repairable functional layer is made of the repairable functional material described above or a repairable functional material prepared by the preparation method described above.

[0016] Furthermore, the base layer is a flexible fabric base layer; Preferably, the flexible fabric base layer is any one of polyethylene terephthalate woven fabric, polyamide knitted fabric, polypropylene spunbond nonwoven fabric, or polyethylene mesh sheet.

[0017] Fourthly, the present invention provides a method for preparing repairable artificial leather, comprising: (A) The repairable functional material is hot-melt extruded to form a molten functional layer; (B) The molten functional layer is bonded to the substrate layer under the action of heat and pressure; (C) Cool and shape the composite structure obtained in step (B) to obtain the repairable artificial leather.

[0018] Furthermore, the extrusion temperature is 170-210°C.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The repairable functional material provided by this invention introduces a modified thermoplastic elastomer with ortho-phenolic hydroxyl groups on its molecular chain, and synergistically incorporates boron-containing compounds to construct a dynamically reversible borate ester bond network. This network can be rapidly activated under moderate heating conditions, enabling the material to achieve efficient, in-situ repair after minor or moderate mechanical damage such as scratches and punctures using everyday household heating tools (such as an electric iron). The repair process relies on the synergistic effect of enhanced molecular chain thermal motion and reversible exchange of borate ester bonds, causing the damaged area to spontaneously reconstruct, restoring surface smoothness and mechanical integrity. At the same time, the thermoplastic elastomer matrix and the modified components have excellent compatibility, ensuring that the repaired area is highly consistent with the original material in terms of color, texture, and mechanical properties, significantly improving the durability and aesthetic consistency of seat covering materials in actual use scenarios such as automobiles and furniture. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 A diagram of the leather before repair is provided for Embodiment 2 of the present invention; Figure 2 A diagram of the repaired leather is provided for Embodiment 2 of the present invention. Detailed Implementation

[0022] Unless otherwise defined herein, the scientific and technical terms used in conjunction with this invention shall have the meanings commonly understood by one of ordinary skill in the art. The meaning and scope of terms shall be clear; however, in any case of potential ambiguity, the definitions provided herein shall prevail over any dictionary or foreign definitions. In this application, unless otherwise stated, the use of "or" means "and / or". Furthermore, the use of the term "comprising" and other forms is non-limiting.

[0023] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Current traditional repair methods rely on professionals and equipment, which ordinary users cannot perform themselves. They are time-consuming, labor-intensive, and costly. Furthermore, traditional repairs are often cover-up methods, making it difficult to restore the original texture and integrity of the material. The repair marks are obvious and affect the aesthetics.

[0025] In view of this, the first aspect of the present invention provides a repairable functional material, the main raw materials for preparation of which include: a thermoplastic elastomer matrix, a modified thermoplastic elastomer, a boron-containing compound and optional additives; wherein the modified thermoplastic elastomer molecular chain has ortho-phenolic hydroxyl groups.

[0026] In this invention, the molecular chain of the modified thermoplastic elastomer contains ortho-phenolic hydroxyl groups (catechol groups). These ortho-phenolic hydroxyl groups form dynamic borate bonds (BO bonds) with borate ions in boron-containing compounds, preferably borax (Na2B4O7·10H2O). These dynamic bonds can undergo reversible breakage and recombination under heating conditions, thereby endowing the material with self-healing capabilities.

[0027] The surface of the repairable functional layer prepared using this repairable functional material is pre-imprinted with a biomimetic leather texture. The flexible fabric base layer is firmly attached to the back of the repairable functional layer through hot melt extrusion composite method, which is used to provide the necessary mechanical strength, tear resistance and dimensional stability for the entire artificial leather, making it easy to cut and sew.

[0028] When scratches, cracks, or other damage occur on the surface of the repairable functional layer, a heating tool (such as an electric iron) is used to locally heat the damaged area to 80-160°C. This causes a reversible transesterification reaction of the dynamic borate ester bonds at the damaged site, reconnecting the broken molecular chains. At the same time, the thermoplastic elastomer matrix softens and flows to fill the cracks. After heating is stopped and the material is allowed to cool naturally, it restores its mechanical integrity and surface smoothness, thus completing the self-repair process.

[0029] This invention offers superior repair results. The repair process involves the physical fusion of the materials themselves, resulting in a completely identical material and color between the repaired area and the surrounding region. When used with a textured embossing head, the surface texture can be reshaped, achieving a seamless repair that is both visually and tactilely imperfect. Furthermore, the entire repair process consumes no additional chemical repair agents, only a small amount of electricity, making it extremely cost-effective and eliminating the significant expense of replacing an entire seat cover for minor damage. In addition, this invention is sustainable and repeatable. Provided the repairable functional layer thickness allows, the same area can withstand multiple damages and repairs, greatly extending the product's lifespan and aligning with green and environmentally friendly sustainable development principles.

[0030] In some preferred embodiments, the modified thermoplastic elastomer has the same main-chain chemical structure as the thermoplastic elastomer matrix. The thermoplastic elastomer matrix includes one or more of styrene-ethylene-butene-styrene block copolymers (SEBS), styrene-ethylene-propylene-styrene block copolymers, and styrene-butadiene-styrene block copolymers; preferably, styrene-ethylene-butene-styrene block copolymers (SEBS).

[0031] Preferably, the modified thermoplastic elastomer is a thermoplastic elastomer obtained by modification with a compound containing dopamine structural units.

[0032] Preferably, the compound containing the dopamine structural unit includes one or more of dopamine hydrochloride, dopamine, levodopa, and dopamine methacrylamide.

[0033] In some preferred embodiments, the boron-containing compound includes one or more of borax (Na2B4O7·10H2O), trimethyl borate, and diboronate. The boron-containing compound acts as a catalyst for the borate ion, forming a thermoresponsive dynamic borate ester bond with the ortho-phenolic hydroxyl group of dopamine-modified SEBS, which is the chemical basis for achieving reversible repair.

[0034] Preferably, the additives include at least one of the following: plasticizer, tackifier, carrier resin, antioxidant, and light stabilizer.

[0035] The plasticizer includes one or more of white mineral oil, paraffin oil, and dioctyl sebacate. In this invention, the plasticizer can reduce the melt viscosity of SEBS, enhance chain segment mobility, and promote crack filling and surface leveling during heating.

[0036] Preferably, the tackifier comprises one or more of hydrogenated petroleum resin, DCPD petroleum resin, and hydrogenated rosin resin; the hydrogenated petroleum resin is C5 petroleum resin, C9 petroleum resin, or C5 / C9 copolymer petroleum resin. The tackifying resin (preferably hydrogenated petroleum resin) mainly acts at the melt rheological level, providing kinetic assurance for the repair material to fill the damaged grooves by controlling the shear viscosity.

[0037] Preferably, the carrier resin comprises one or more of polypropylene, low-density polyethylene, and ethylene-vinyl acetate copolymer. The carrier resin serves as a dispersion carrier for the functional masterbatch, simultaneously enhancing overall rigidity and dimensional stability, and balancing the softening effect caused by high plasticization.

[0038] Preferably, the antioxidant includes one or more of hindered phenolic antioxidants and phosphite antioxidants.

[0039] Preferably, the light stabilizer includes hindered amine light stabilizers.

[0040] In some preferred embodiments, the main raw materials include, by weight, 100 parts of the total weight of the thermoplastic elastomer matrix and the modified thermoplastic elastomer. 2-6 parts of boron-containing compound, for example, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, etc., preferably 2-5 parts; And 70.8-153 parts of adjuvants, specifically including: 35-85 parts of plasticizer, such as 35 parts, 40 parts, 50 parts, 60 parts, 70 parts, 80 parts, 85 parts, etc., more preferably 40-80 parts; 15-45 parts of thickener, for example, 15 parts, 20 parts, 30 parts, 40 parts, 45 parts, etc., more preferably 20-40 parts; 5-35 parts of carrier resin, for example, 5 parts, 10 parts, 20 parts, 30 parts, 35 parts, etc., more preferably 10-30 parts; 0.5-2 parts antioxidant, for example, 0.5 parts, 1 part, 1.5 parts, 2 parts, etc.; And 0.3-1 parts of light stabilizer, such as 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, etc.

[0041] Preferably, based on the total weight of the thermoplastic elastomer matrix and the modified thermoplastic elastomer being 100%, the modified thermoplastic elastomer accounts for 10%-50% of the total weight of the thermoplastic elastomer matrix and the modified thermoplastic elastomer, for example, it can be 10%, 20%, 30%, 40%, 50%, etc., and more preferably 15%-30%.

[0042] A second aspect of the present invention provides a method for preparing a repairable functional material, comprising: (a) A premix is ​​prepared by premixing a thermoplastic elastomer matrix, a modified thermoplastic elastomer, a boron-containing compound, and optional additives. (b) The premixed material is melt-blended and granulated to obtain the repairable functional material.

[0043] The method for preparing repairable functional materials provided by this invention modifies only a portion of the thermoplastic elastomer with dopamine (as a functionalized masterbatch), and then blends the functionalized masterbatch with the thermoplastic elastomer matrix. By utilizing the dynamic borate ester bonds between the ortho-phenolic hydroxyl groups (catechol groups) on the dopamine-modified thermoplastic elastomer and borax, a cross-linking network is constructed, which achieves self-healing function while significantly reducing modification costs and process complexity, and is conducive to large-scale industrial production.

[0044] In some preferred embodiments, the premixing time is 3-10 minutes, for example, 3 minutes, 6.5 minutes, 10 minutes, etc., and the rotation speed during the premixing process is 300-800 rpm, for example, 300 rpm, 550 rpm, 800 rpm, etc.

[0045] Preferably, the melt blending temperature is 160-200℃, for example, it can be 160℃, 170℃, 180℃, 190℃, 200℃, etc.

[0046] Preferably, the modified thermoplastic elastomer is prepared by the following method: The modified thermoplastic elastomer is obtained by dissolving and mixing a thermoplastic elastomer, a compound containing dopamine structural units, and an organic solvent, and reacting them at room temperature under alkaline conditions. Preferably, the pH value of the alkaline condition is 8.0-9.0, and the reaction time is 12-24 hours, for example, 12 hours, 18 hours, 24 hours, etc.

[0047] A second aspect of the present invention provides a repairable artificial leather, comprising: a repairable functional layer, and a base layer laminated to the back of the repairable functional layer; the repairable functional layer is made of the repairable functional material described above or a repairable functional material prepared by the preparation method described above.

[0048] Among them, the repairable functional layer serves as the surface and working surface of the leather.

[0049] In some preferred embodiments, the base layer is a flexible fabric base layer. The flexible fabric base layer is any one of polyethylene terephthalate (PET) woven fabric, polyamide (PA6 or PA66) knitted fabric, polypropylene (PP) spunbond nonwoven fabric, or polyethylene (PE) mesh sheet.

[0050] A fourth aspect of the present invention provides a method for preparing repairable artificial leather, comprising: (A) The repairable functional material is hot-melt extruded to form a molten functional layer; (B) The molten functional layer is bonded to the substrate layer under the action of heat and pressure; (C) Cool and shape the composite structure obtained in step (B) to obtain the repairable artificial leather.

[0051] The repairable artificial leather provided by this invention is a thermoplastic elastomer (TPE) leather with repairable function. It has a simple structure, can be operated by users, has extremely low repair cost, and the repair effect is almost seamless and can be repaired repeatedly.

[0052] In some preferred embodiments, the extrusion temperature is 170-210°C.

[0053] The present invention will be further illustrated by the following examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0054] Preparation Example 1 This preparation example provides a dopamine-modified SEBS, and its preparation method is as follows: SEBS was dissolved in an organic solvent (toluene), and 5 wt% dopamine hydrochloride (i.e., the mass of dopamine hydrochloride accounts for 5% of the oven-dry mass of SEBS) was added. The mixture was stirred and reacted at room temperature (25°C) under alkaline conditions (pH 8.0~9.0) for 18 hours. After the reaction was completed, the mixture was precipitated, filtered, washed, and dried to obtain dopamine-modified SEBS functionalized masterbatch.

[0055] In the following examples, the dopamine-modified SEBS prepared in Preparation Example 1 above was used as the functionalized masterbatch.

[0056] Example 1 This embodiment provides a repairable artificial leather, the material formula of which is shown in Table 1. The preparation process of the repairable artificial leather is as follows: Step 1: Premixing Weigh each component according to the above formula, put them into a high-speed mixer, and stir at 500 rpm for 5 minutes at room temperature to allow the liquid white mineral oil to fully impregnate SEBS and other solid materials, forming a uniform premix.

[0057] Step 2: Melt blending and granulation The premixed material is fed into a co-rotating twin-screw extruder. The extruder temperature is set to 160-200℃ and the screw speed is 300rpm. After melting and mixing, the material is extruded into strips through the die, cooled in a water tank, and finally cut into uniform granules by a pelletizer for later use.

[0058] Step 3: Hot melt extrusion lamination The TPE granules obtained in step 2 are fed into a single-screw extruder, and the extrusion temperature is set to 170-200℃. The molten TPE is extruded through a T-die to a thickness of 0.5mm. Simultaneously, a polyester base fabric (flexible fabric substrate layer) is guided to the composite roller gap and, under the clamping of an embossed steel roller (temperature 70℃) and a silicone roller (temperature 50℃), is composited with the TPE melt. The composite pressure is 6MPa, and the production line speed is set to 5 m / min.

[0059] Step 4: Cooling and winding The composite material is immediately cooled and shaped by a cooling roller assembly (water temperature 15℃), and finally wound up to obtain a repairable artificial leather product.

[0060] Example 2 This embodiment provides a repairable artificial leather, which differs from Embodiment 1 in that: the material formula is shown in Table 1, and its preparation process differs from that of Embodiment 1 in that: In step 3, since the formula melt strength is higher, the compounding pressure can be finely adjusted to 7 MPa, and the production line speed can be increased to 7 m / min.

[0061] Example 3 This embodiment provides a repairable artificial leather, which differs from Embodiment 1 in that: the material formula is shown in Table 1, and its preparation process differs from that of Embodiment 1 in that: In step 2, due to the high viscosity of the system, it is necessary to ensure that the twin-screw extruder has sufficient torque. The temperature setting can be slightly increased by about 5°C to ensure good plasticization.

[0062] In step 3, the extruder temperature can be set within the range of 185-205℃. Due to the slightly poor melt flowability, it is necessary to ensure uniform die temperature. The compounding pressure can be increased to 8 MPa, and the production line speed can be set to 9 m / min.

[0063] Example 4 This embodiment provides a repairable artificial leather, which differs from Embodiment 1 in that the material formula is shown in Table 1, wherein the ratio of SEBS to dopamine-modified SEBS and the amount of borax added are different, while the rest are the same as in Embodiment 1.

[0064] Example 5 This embodiment provides a repairable artificial leather, which differs from Embodiment 3 in that the material formula is shown in Table 1, wherein the ratio of SEBS to dopamine-modified SEBS and the amount of borax added are different, while the rest are the same as in Embodiment 3.

[0065] Example 6 This embodiment provides a repairable artificial leather, which differs from Embodiment 1 in that the material formulation is shown in Table 1, wherein the amounts of white mineral oil, hydrogenated petroleum resin and polypropylene added are different, while the rest are the same as in Embodiment 1.

[0066] Example 7 This embodiment provides a repairable artificial leather, which differs from Embodiment 3 in that the material formula is shown in Table 1, wherein the amounts of white mineral oil, hydrogenated petroleum resin and polypropylene added are different, while the rest are the same as in Embodiment 3.

[0067] Comparative Example 1 This comparative example provides a repairable artificial leather, which differs from Example 2 in that the material formulation does not contain dopamine-modified SEBS, and the amount of styrene-ethylene-butene-styrene block copolymer (SEBS) is adjusted to 100 parts.

[0068] Comparative Example 2 This comparative example provides a repairable artificial leather, which differs from Example 2 in that the material formulation does not contain borax.

[0069] Comparative Example 3 This comparative example provides a commercially available conventional PU self-healing leather.

[0070] Table 1

[0071] Test case The repairable artificial leather provided in the above embodiments and comparative examples was used as a sample for testing.

[0072] Test method: Using an 18mm wide utility knife conforming to QB / T 2961-2017 (brand new blade, cutting angle of about 25°), place the sample flat on a rigid support surface, and under a constant vertical load of 10 N, scratch the sample surface unidirectionally at a speed of 100 mm / min. The scratch length is 50 mm and the depth is through the repairable functional layer.

[0073] Repair: Use a 120℃ electric iron to heat the scratch and press lightly (pressing pressure is 10N).

[0074] The test results are shown in Table 2.

[0075] Table 2

[0076] The results in Table 1 show that the dynamic borate ester bond network is the core mechanism of the self-healing function. Comparative Example 1 (without dopamine-modified SEBS) and Comparative Example 2 (without borax) showed no significant repair effect after heating, indicating that both the ortho-phenolic hydroxyl group and the boron-containing compound are indispensable; effective repair cannot be achieved solely through the physical melting of the TPE matrix. This invention is superior to existing technologies. The repair effect of Comparative Example 3 (commercially available PU self-healing leather) is significantly inferior to that of the embodiments of this invention, proving that this invention has a superior repair effect.

[0077] The balance of the formulation directly affects the repair efficiency. Examples 1-3 are a series of formulations with a balanced ratio of plasticizer, tackifying resin and PP. The dynamic bond network is complete, the chain segment mobility and melt flowability are optimally matched, and the repair effect reaches an excellent level.

[0078] Among them, such as Figures 1-2 As shown, the scratches completely disappeared after repair using the material in Example 2, resulting in a smooth surface, uniform color, and consistent feel, achieving a scratch-free repair. Example 2 (Shore A hardness 75±5) combines suitable feel and mechanical strength, with a moderate repair time and optimal overall performance. This formula, while maintaining good repairability, gives the material higher strength, making it suitable for full seat upholstery. Example 1 is softer (55±5), and its high oil content significantly reduces the melt viscosity of the material, promoting flow and refusion during the repair process. It has slightly lower strength but repairs fastest, making it a highly repairable material suitable for automotive seat contact surfaces. Example 3 is harder (90±5), with the highest strength but the longest repair time. It is a material with high hardness and support while retaining repairability.

[0079] Example 4 suffered from excessively high dynamic borate ester bond density and restricted chain segment movement, while Example 5 suffered from insufficient total amount of ortho-phenolic hydroxyl groups and low dynamic bond density, both of which led to decreased repair efficiency. Examples 6-7, due to deviations in formulation from the equilibrium range, showed inferior overall results compared to the other examples.

[0080] It is evident that the proportions in Examples 1-3 are more balanced, with better synergy between dynamic borate bond density and chain segment mobility, resulting in a superior repair effect. When the content of functional masterbatch is adjusted from high to low within the preferred range (15%-30%) (as in Examples 1, 2, and 3), appropriately increasing the amount of borax can effectively maintain the dynamic borate bond density and ensure stable repair effect. However, in Example 5, the functional masterbatch is only 10 parts (accounting for 10%). Although the amount of borax is increased to 6 parts, the total amount of ortho- and posterior phenolic hydroxyl groups is insufficient, failing to form a sufficiently dense dynamic borate bond network. Therefore, the repair effect is not as good as in Example 3.

[0081] In summary, this invention endows materials with intrinsic self-healing capabilities by synergistically constructing a dynamic borate ester bond network with ortho-phenolic hydroxyl groups and boron-containing compounds; through formulation control, effective repair is achieved, meeting the needs of different application scenarios.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A repairable functional material, characterized in that, The main raw materials for preparation include: Thermoplastic elastomer matrix, modified thermoplastic elastomer, boron-containing compound and optional additives; The modified thermoplastic elastomer molecular chain contains ortho-phenolic hydroxyl groups.

2. The repairable functional material according to claim 1, characterized in that, The modified thermoplastic elastomer has the same main chain chemical structure as the thermoplastic elastomer matrix; Preferably, the thermoplastic elastomer matrix comprises one or more of styrene-ethylene-butene-styrene block copolymers, styrene-ethylene-propylene-styrene block copolymers, and styrene-butadiene-styrene block copolymers; Preferably, the modified thermoplastic elastomer is a thermoplastic elastomer obtained by modification with a compound containing dopamine structural units; Preferably, the compound containing the dopamine structural unit includes one or more of dopamine hydrochloride, dopamine, levodopa, and dopamine methacrylamide.

3. The repairable functional material according to claim 1, characterized in that, The main raw materials for preparation, by weight, include: 100 parts of the total weight of the thermoplastic elastomer matrix and the modified thermoplastic elastomer, 2-6 parts of boron-containing compound and 70.8-153 parts of additives; Preferably, the boron-containing compound is present in the form of 2-5 parts; Preferably, the modified thermoplastic elastomer accounts for 10%-50% of the total weight of the thermoplastic elastomer matrix and the modified thermoplastic elastomer, and more preferably 15%-30%.

4. The repairable functional material according to claim 1, characterized in that, The boron-containing compound includes one or more of borax, trimethyl borate, and diboronate; Preferably, the additives include at least one of: plasticizer, tackifier, carrier resin, antioxidant and light stabilizer; Preferably, the plasticizer includes one or more of white mineral oil, paraffin oil, and dioctyl sebacate; Preferably, the tackifier comprises one or more of hydrogenated petroleum resin, DCPD petroleum resin, and hydrogenated rosin resin; Preferably, the carrier resin comprises one or more of polypropylene, low-density polyethylene, and ethylene-vinyl acetate copolymer; Preferably, the antioxidant includes one or more of hindered phenolic antioxidants and phosphite antioxidants; Preferably, the light stabilizer includes a hindered amine light stabilizer; Preferably, the additives include: 35-85 parts plasticizer, 15-45 parts tackifier, 5-35 parts carrier resin, 0.5-2 parts antioxidant, and 0.3-1 part light stabilizer; More preferably, the additives include: 40-80 parts plasticizer, 20-40 parts tackifier, 10-30 parts carrier resin, 0.5-2 parts antioxidant and 0.3-1 part light stabilizer.

5. The method for preparing the repairable functional material according to any one of claims 1-4, characterized in that, include: (a) A premix is ​​prepared by premixing a thermoplastic elastomer matrix, a modified thermoplastic elastomer, a boron-containing compound, and optional additives. (b) The premixed material is melt-blended and granulated to obtain the repairable functional material.

6. The method for preparing the repairable functional material according to claim 5, characterized in that, The premixing time is 3-10 minutes, and the rotation speed during the premixing process is 300-800 rpm; Preferably, the melt blending temperature is 160-200℃; Preferably, the modified thermoplastic elastomer is prepared by the following method: The modified thermoplastic elastomer is obtained by dissolving and mixing a thermoplastic elastomer, a compound containing dopamine structural units, and an organic solvent, and reacting them at room temperature under alkaline conditions. Preferably, the pH value of the alkaline conditions is 8.0-9.0, and the reaction time is 12-24 hours.

7. A repairable artificial leather, characterized in that, include: A repairable functional layer, and a base layer composited on the back side of the repairable functional layer; The repairable functional layer is made of the repairable functional material according to any one of claims 1-4 or the repairable functional material prepared by the preparation method according to claim 5 or 6.

8. The repairable artificial leather according to claim 7, characterized in that, The base layer is a flexible fabric base layer; Preferably, the flexible fabric base layer is any one of polyethylene terephthalate woven fabric, polyamide knitted fabric, polypropylene spunbond nonwoven fabric, or polyethylene mesh sheet.

9. The method for preparing repairable artificial leather as described in claim 8, characterized in that, include: (A) The repairable functional material is hot-melt extruded to form a molten functional layer; (B) The molten functional layer is bonded to the substrate layer under the action of heat and pressure; (C) Cool and shape the composite structure obtained in step (B) to obtain the repairable artificial leather.

10. The method for preparing repairable artificial leather according to claim 9, characterized in that, The extrusion temperature is 170-210℃.

Images