Thermoplastic elastomer material, process for its preparation and use

Abstract

Abstract of this invention discloses a thermoplastic elastomer material, its preparation method, and its application. The preparation method of this application includes the following steps: S1, preparation of bio-premix: mixing cationic polysaccharides with protein-based biopolymers to obtain a first polyelectrolyte complex powder; mixing cationic antibacterial peptides with glycosaminoglycans to form a second polyelectrolyte complex; mixing porous adsorbent material with the above two complex powders to obtain a biofunctional premix; S2, preparation of matrix premix: adding matrix resin and additives to a mixer to obtain a matrix premix; S3, low-temperature feeding extrusion: extruding the matrix premix, biofunctional premix, porous adsorbent material, and functional masterbatch through a twin-screw extruder. This application provides a method for preparing a thermoplastic elastomer material that can simultaneously achieve low sweat exudation, long-lasting broad-spectrum antibacterial effect, deep skin-friendly moisturizing, and effectively protect heat-sensitive biological components.

Description

Technical Field

[0001] This invention relates to the technical field of polymer material modification, specifically to a thermoplastic elastomer material, its preparation method, and its application. Background Technology

[0002] With the development of the Internet of Things (IoT) and wearable technology, smartwatches, smart bracelets, AR / VR glasses, and other smart wearable devices have become an indispensable part of people's daily lives. These devices typically need to be in close contact with the skin for extended periods, requiring the materials used for their casings and contact components to possess excellent skin-friendliness, biocompatibility, and sweat resistance. Thermoplastic elastomers (TPEs), due to their soft touch, good processability, and recyclability, are widely used in the manufacture of wristbands, headbands, and skin-contact sensor housings for smart wearable devices.

[0003] However, existing thermoplastic elastomer materials still have shortcomings when applied to smart wearable scenarios. Firstly, they have poor sweat resistance and are prone to becoming sticky. Human sweat contains various components such as water, salts (e.g., sodium chloride), lactic acid, urea, and fatty acids. Existing thermoplastic elastomer materials, especially those based on styrene-based elastomers (e.g., SEBS, SBS), tend to have small-molecule additives (such as processing oils and antioxidants) migrate to the material surface after prolonged contact with sweat, leading to a sticky, greasy feel and even "oil separation." This not only severely affects wearing comfort, but the released chemicals may also irritate sensitive skin, causing contact dermatitis.

[0004] Secondly, the antibacterial effect is not long-lasting. Warm and humid wearing environments easily breed bacteria, leading to odors and excessive bacterial colonies. Although the industry often addresses this issue by adding inorganic silver ion antibacterial agents, silver ions are easily lost through prolonged friction with the skin and rinsing with sweat, causing the antibacterial performance to rapidly decline over time. Furthermore, simple physical addition often results in uneven dispersion of the antibacterial agent in the matrix resin, making it difficult to form a long-lasting and stable antibacterial barrier.

[0005] Secondly, they lack skin-friendly moisturizing properties and have an unpleasant feel. Existing thermoplastic elastomer materials often prioritize mechanical strength and cost, neglecting surface energy and biocompatibility. While some materials add slip agents to reduce the coefficient of friction, these are mostly topical or small-molecule migration-type additives. Initially, the feel may be acceptable, but over time, the agent migration can cause dryness or greasiness. More importantly, existing materials lack the ability to maintain the moisture content of the skin's stratum corneum. Long-term wear can easily lead to dryness and itching at the contact points, failing to meet the high standards of "skin-friendliness" required for high-end maternal and infant care and medical-grade smart wearables.

[0006] Finally, there is the challenge of processing and protecting heat-sensitive functional components. To address these issues, the industry has attempted to introduce natural biopolymers such as chitosan, ε-polylysine, and hyaluronic acid to enhance the antibacterial, moisturizing, and biocompatibility properties of materials. However, these bioactive components are typically extremely sensitive to heat, and are prone to oxidative degradation, molecular chain breakage, or loss of bioactivity during the conventional high-temperature melt processing of thermoplastic elastomers. While existing technologies include research on low-temperature processing of thermoplastic elastomers, these efforts primarily focus on reducing odor or volatile matter, and do not provide an effective and systematic solution for protecting the activity of heat-sensitive bioactive components.

[0007] In summary, although various thermoplastic elastomer modification schemes exist in the prior art, there is still a lack of a thermoplastic elastomer and its preparation method that can simultaneously achieve low sweat exudation, long-lasting broad-spectrum antibacterial effect, deep skin-friendly moisturizing, and effective protection of the activity of heat-sensitive biological components. This severely restricts the development of high-end smart wearable devices. Therefore, there is an urgent need in this field to develop a thermoplastic elastomer material and its preparation method that can simultaneously achieve low sweat exudation, long-lasting broad-spectrum antibacterial effect, deep skin-friendly moisturizing, and effective protection of the activity of heat-sensitive biological components to meet the skin-contact application requirements of high-end smart wearable devices. Summary of the Invention

[0008] This application provides a thermoplastic elastomer material, its preparation method, and its application, which can simultaneously achieve anti-sweat and low exudation, long-lasting broad-spectrum antibacterial effect, deep skin-friendly moisturizing, and effectively protect the activity of heat-sensitive biological components.

[0009] On one hand, this application provides a method for preparing a thermoplastic elastomer material, comprising the following steps: S1, preparation of a bio-premix: cationic polysaccharide and protein-based biopolymer are mixed in an acidic aqueous solution at a mass ratio, the pH is adjusted, a crosslinking agent is added for crosslinking, and after freeze-drying and pulverization, a first polyelectrolyte complex powder is obtained; cationic antibacterial peptides and glycosaminoglycans are added to deionized water at a mass ratio, and stirred to form a second polyelectrolyte complex, which is then freeze-dried and pulverized to obtain a second polyelectrolyte complex powder; a porous adsorbent material is mixed uniformly with the above two complex powders to obtain a biofunctional premix. S2, Preparation of matrix premix: Hydrogenated styrene-butadiene-styrene block copolymer, styrene-butadiene-styrene block copolymer, polypropylene, polyethylene, polycaprolactone, compatibilizer, calcium carbonate, antioxidant, lubricant and VOC scavenger are added to a mixer and mixed evenly to obtain matrix premix; S3, Low-temperature feeding extrusion: The matrix premix obtained in step S2 is added from the main feed port of the twin-screw extruder, the biofunctional premix obtained in step S1 is added from the upstream side feed port of the twin-screw extruder, and the commercially available functional masterbatch is added from the side feed port adjacent to the die head of the twin-screw extruder.

[0010] By adopting the above technical solution, this application first prepares a first polyelectrolyte complex by cross-linking cationic polysaccharides and protein-based biopolymers under acidic conditions, and simultaneously prepares a second polyelectrolyte complex by combining cationic antibacterial peptides and glycosaminoglycans. The two are then mixed with porous adsorbent materials to form a biofunctional premix. Subsequently, the matrix resin components are mixed to prepare a matrix premix. Finally, a low-temperature multi-segment side-feeding process is adopted, in which the matrix premix is ​​added from the main feed port, the biofunctional premix is ​​added from the upstream side feed port, and the functional masterbatch is added from the side feed port adjacent to the machine head. Through the synergy of porous adsorbent materials with the first and second polyelectrolyte complexes, a dual anti-sweat barrier is constructed.

[0011] Preferably, in step S1, the cationic polysaccharide is selected from one or more of chitosan, carboxymethyl chitosan, quaternized chitosan, and cationic starch; and the protein-based biopolymer is selected from one or more of gelatin, collagen, silk fibroin, and soy protein.

[0012] By employing the above technical solution, in this application, cationic polysaccharides (such as chitosan) are rich in amino groups (-NH2), which protonate and become positively charged under acidic conditions; low isoelectric point protein-based biopolymers such as type B gelatin and collagen are selected, with isoelectric points of 4.7-5.3. Under reaction conditions of pH 5.0-6.0, where the pH is higher than their isoelectric point, the carboxyl groups on the molecular chain dissociate and become negatively charged. The two self-assemble in aqueous solution through electrostatic attraction to form a polyelectrolyte complex.

[0013] Because the polyelectrolyte complex formed by the electrostatic assembly and cross-linking of cationic polysaccharides and protein-based biopolymers is rich in polar functional groups such as amino and carboxyl groups on its surface, these functional groups can strongly coordinate and chelate lactate ions, urea molecules, and sodium ions in sweat, chemically binding them to the interior of the material. This prevents small sweat molecules from migrating outwards or damaging the matrix inwards, altering the microenvironment of the material surface and inhibiting bacterial growth by removing substances (lactic acid, urea) from sweat.

[0014] Preferably, in step S1, the crosslinking agent is selected from one or more of genipin, glutaraldehyde, citric acid, and 1,4-butanediol diglycidyl ether; the cationic polysaccharide and the protein-based biopolymer form a polyelectrolyte complex through electrostatic interaction and crosslinking reaction.

[0015] By adopting the above technical solution, after adding cross-linking agents such as Genipin in this application, their active groups undergo Michael addition or nucleophilic substitution reactions with the active hydrogen on polysaccharides and proteins, forming a covalent cross-linking network on the basis of electrostatic complexation. This prevents them from dissociating due to thermal motion during subsequent processing. More importantly, the abundant positive and negative charge groups on their surface constitute chelating sites, which can adsorb lactate, urea molecules and sodium ions in sweat, thus playing a role in chemical chelation and anti-sweat.

[0016] Preferably, in step S1, the cationic antimicrobial polypeptide is selected from one or more of ε-polylysine and lactobacillus peptide; and the glycosaminoglycan is selected from one or more of hyaluronic acid, chondroitin sulfate, and heparin.

[0017] By employing the above-mentioned technical solution, the cationic antimicrobial peptides (such as ε-polylysine) in this application carry a positive charge and are adsorbed onto the negatively charged glycosaminoglycan (such as hyaluronic acid) chains through electrostatic interactions. For example, ε-polylysine, as an antimicrobial peptide, can adsorb the negatively charged bacterial cell walls due to its positive charge. The cationic antimicrobial peptides can rapidly adsorb and penetrate the cell walls, disrupting cell membrane permeability and achieving broad-spectrum contact killing of Staphylococcus aureus, Escherichia coli, etc. Meanwhile, glycosaminoglycans (such as hyaluronic acid), as natural moisturizing factors, can bind environmental water molecules through hydrogen bonds when a large number of hydroxyl and carboxyl groups on their molecular chains are exposed on the material surface, forming a stable biomimetic hydration layer at the skin contact interface, locking in stratum corneum moisture, and achieving deep moisturizing. The two components combine through electrostatic interactions to form a stable structure, avoiding the migration and loss of single components during processing and use.

[0018] Preferably, the porous adsorbent material in step S1 is selected from one or more of mesoporous silica, mesoporous titanium dioxide, and mesoporous alumina, with a pore size of 2-3 nm and a specific surface area of ​​600-1200 m². 2 / g.

[0019] By adopting the above technical solutions, the porous adsorbent materials in this application include mesoporous silica, mesoporous titanium dioxide, and mesoporous alumina, all of which have regular nanopores and high specific surface area. Their pore size matches the size of small sweat molecules, and through physical retention and capillary coagulation, they adsorb the odors in sweat into the pores, preventing them from migrating to the material surface and forming an anti-sweat barrier.

[0020] Preferably, in step S3, the temperature of each section of the twin-screw extruder is set as follows: Zone 1 100-130℃, Zone 2 110-140℃, Zone 3 120-150℃, Zone 4 130-160℃, Zone 5 130-160℃, Zone 6 120-150℃, Zone 7 110-140℃, and Zone 8 100-130℃; the screw speed is 100-400 rpm, and the vacuum degree is -0.08 to -0.04 MPa.

[0021] Preferably, the commercially available functional masterbatch in step S3 includes one or more of the following: nano-silver antibacterial masterbatch, organosilicon elastic microsphere masterbatch, zinc oxide antibacterial masterbatch, and titanium dioxide antibacterial masterbatch; the compatibilizer is selected from one or more of the following: maleic anhydride-grafted polylactic acid, maleic anhydride-grafted polypropylene, and maleic anhydride-grafted polyethylene.

[0022] On one hand, this application provides a thermoplastic elastomer material, which, by weight, comprises the following components: a matrix resin component: 15-30 parts of hydrogenated styrene-butadiene-styrene block copolymer, 5-20 parts of styrene-butadiene-styrene block copolymer, 10-25 parts of polypropylene, 10-25 parts of polyethylene, and 3-15 parts of polycaprolactone; a bio-based composite component: 10-30 parts of a first polyelectrolyte complex, 5-20 parts of a second polyelectrolyte complex, and 1-8 parts of porous adsorbent material; an additive component: 2-10 parts of compatibilizer, 5-20 parts of calcium carbonate, 0.3-2.0 parts of antioxidant, 0.1-1.5 parts of lubricant, and 0.3-3.0 parts of VOC scavenger; and commercially available functional masterbatch: 1-5 parts of antibacterial functional masterbatch and 3-12 parts of slip functional masterbatch.

[0023] Preferably, the amount of the thermoplastic elastomer material added to the downstream thermoplastic elastomer matrix is ​​2-15 wt%, and the product obtained after injection molding or extrusion molding meets the following performance requirements: tensile strength retention rate after immersion in artificial sweat for 72 hours is greater than or equal to 80%, TVOC content is less than or equal to 50 μg / g, antibacterial rate against Staphylococcus aureus and Escherichia coli is greater than or equal to 99%, and stratum corneum moisture content is increased by greater than or equal to 15%.

[0024] On the other hand, this application provides an application of a thermoplastic elastomer material, which is used to prepare watch straps, wristbands, skin-contact sensor housings, or AR / VR device contact parts for smart wearable devices. When the smart wearable device is worn close to the skin for a long time, the skin irritation index of its contact surface is less than or equal to 1.0.

[0025] One or more technical solutions provided in this application have at least the following technical effects or advantages: 1. This application utilizes the nanopores of a porous adsorption material to physically trap small molecules such as urea and lactic acid in sweat, while simultaneously chemically coordinating and chelating these small molecules through the polar functional groups on the surface of the first polyelectrolyte complex. This mechanism blocks the migration pathway of small sweat molecules to the material surface, improving the durability and wearing comfort of smart wearable devices.

[0026] 2. This application utilizes the positively charged cationic antibacterial peptides in the second polyelectrolyte complex to directly destroy bacterial cell walls through electrostatic adsorption; at the same time, the chelating effect of the first polyelectrolyte complex on sweat nutrients disrupts the bacterial growth environment, thereby increasing the antibacterial rate of the material.

[0027] 3. This application introduces glycosaminoglycans, utilizing their water absorption and retention properties to construct a biomimetic biohydration layer on the material surface, making it more comfortable to contact with the skin. Simultaneously, the efficient chelation of sweat by the first polyelectrolyte complex ensures that no small-molecule oils or plasticizers are released from the material surface. This results in a dry, comfortable feel for the wearer, rather than the traditional plastic or oily sensation, making it particularly suitable for smart wearable products that require skin contact.

[0028] 4. This application avoids the thermal degradation threshold of biomacromolecules from a thermodynamic perspective by setting a low-temperature processing window; by specifying that the biofunctional premix is ​​added from the upstream side feed port and the functional masterbatch is added from the side feed port adjacent to the die head, this control strategy ensures that the genipin cross-linked structure and bioactive functional groups remain intact after high-temperature melting, thus guaranteeing the true realization of anti-sweat, antibacterial and moisturizing functions. Detailed Implementation

[0029] This application provides a thermoplastic elastomer material, its preparation method, and its application, which can simultaneously achieve anti-sweat and low exudation, long-lasting broad-spectrum antibacterial effect, deep skin-friendly moisturizing, and effectively protect the activity of heat-sensitive biological components.

[0030] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0031] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or server that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or modules not explicitly listed or inherent to such processes, methods, products, or devices.

[0032] Example 1 Example 1 of this application provides a raw material and preparation method for a thermoplastic elastomer material. Firstly, the raw material proportions of Example 1, by weight, are as follows: The matrix resin composition is as follows: 20 parts of hydrogenated styrene-butadiene-styrene block copolymer (SEBS), 10 parts of styrene-butadiene-styrene block copolymer (SBS), 15 parts of polypropylene (PP), 15 parts of polyethylene (PE), and 8 parts of polycaprolactone (PCL).

[0033] Additive components: 5 parts maleic anhydride grafted polylactic acid (MAH-g-PLA), 10 parts calcium carbonate (particle size 2μm), 1 part antioxidant 1010 / 168 (1:1 compound), 0.5 parts lubricant (vinyl bis-stearamide, EBS), and 1 part VOC scavenger (cyclodextrin inclusion type).

[0034] Commercially available functional masterbatches: 2 parts of nano silver antibacterial masterbatch (silver content 2000ppm, carrier SEBS) and 6 parts of organosilicon elastic microsphere masterbatch (microsphere particle size 5μm).

[0035] Furthermore, a method for preparing a thermoplastic elastomer material is disclosed, the specific steps of which are as follows: S1. Preparation of biological premix: To prepare the first polyelectrolyte complex, 20g of chitosan and 10g of gelatin were added to 1000mL of 2wt% acetic acid aqueous solution and stirred in a water bath at 50℃ until completely dissolved. The pH was adjusted to 6.0 with 1mol / L NaOH solution, and 0.3g of genipin was added. The mixture was reacted at 45℃ in the dark for 16 hours. After freeze-drying, the mixture was pulverized and passed through a 100-mesh sieve to obtain the first polyelectrolyte complex powder. To prepare the second polyelectrolyte complex, 6g of ε-polylysine and 4g of hyaluronic acid were added to 500mL of deionized water, stirred at 35℃ for 3 hours, and then freeze-dried and pulverized through a 100-mesh sieve to obtain the second polyelectrolyte complex powder. 3g of mesoporous silica and the two aforementioned composite powders were added to a mixer and mixed thoroughly to obtain a biofunctional premix. The bio-based composite component comprises 20 parts of the first polyelectrolyte composite, 10 parts of the second polyelectrolyte composite, and 3 parts of porous adsorbent material. S2. Prepare matrix premix: Add the matrix resin component and additive group from the raw materials to a high-speed mixer according to the weight proportions, mix at 500 rpm for 5 minutes to obtain matrix premix.

[0036] S3. Low-Temperature Feeding Extrusion: The obtained matrix premix is ​​fed into the main feed port of Zone 1 of the twin-screw extruder, the obtained biofunctional premix is ​​fed into the side feed port of Zone 3, and the commercially available nano-silver antibacterial masterbatch and organosilicon elastic microsphere masterbatch are fed into the side feed port of Zone 5. The temperature settings of each zone of the twin-screw extruder are as follows: Zone 1 115℃, Zone 2 125℃, Zone 3 135℃, Zone 4 145℃, Zone 5 135℃, Zone 6 125℃, Zone 7 115℃, Zone 8 105℃, screw speed 200 rpm, vacuum degree -0.07 MPa, extrusion granulation to obtain thermoplastic elastomer.

[0037] Example 2 The difference between Example 2 and Example 1 lies in the choice of cationic polysaccharide and protein-based biopolymer. Example 2 uses carboxymethyl chitosan and collagen cross-linked to obtain the first polyelectrolyte complex. The specific steps are as follows: S1. Preparation of biological premix: To prepare the first polyelectrolyte complex, 20g of carboxymethyl chitosan and 10g of collagen were added to 1000mL of 2wt% acetic acid aqueous solution and stirred in a water bath at 50℃ until completely dissolved. The pH was adjusted to 6.0 with 1mol / L NaOH solution, and 0.3g of genipin was added. The mixture was reacted at 45℃ in the dark for 16 hours. After freeze-drying, the mixture was pulverized and passed through a 100-mesh sieve to obtain the first polyelectrolyte complex powder. To prepare the second polyelectrolyte complex, 6g of ε-polylysine and 4g of hyaluronic acid were added to 500mL of deionized water, stirred at 35℃ for 3 hours, and then freeze-dried and pulverized through a 100-mesh sieve to obtain the second polyelectrolyte complex powder. 3g of mesoporous silica and the two composite powders mentioned above were added to a mixer and mixed evenly to obtain a biofunctional premix. In Example 1 of this application, the mesoporous silica had a pore size of 2-3nm and a specific surface area of ​​800-1000m². 2 / g. In addition, the bio-based composite component contains 20 parts of the first polyelectrolyte complex, 10 parts of the second polyelectrolyte complex, and 3 parts of porous adsorbent material.

[0038] S2. Preparation of matrix premix: Add the matrix resin component and the auxiliary component to a high-speed mixer and mix at 500 rpm for 5 minutes to obtain the matrix premix.

[0039] S3. Low-Temperature Feeding Extrusion: The obtained matrix premix is ​​added through the main feed port in Zone 1 of the twin-screw extruder, the obtained biofunctional premix is ​​added through the side feed port in Zone 3, and the commercially available nano-silver antibacterial masterbatch and organosilicon elastic microsphere masterbatch are added through the side feed port in Zone 5. The weight proportions of the matrix resin component, auxiliary component, and commercially available functional masterbatch are the same as in Example 1. The temperatures of each zone of the twin-screw extruder are the same as in Example 1.

[0040] Example 3 The difference between Example 3 and Example 1 lies in the choice of crosslinking agent. Example 3 uses a 25% (w / w) aqueous solution of glutaraldehyde. The specific steps are as follows: S1. Preparation of biological premix: To prepare the first polyelectrolyte complex, 20g of chitosan and 10g of gelatin were added to 1000mL of 2wt% acetic acid aqueous solution and stirred in a water bath at 50℃ until completely dissolved. The pH was adjusted to 6.0 with 1mol / L NaOH solution, and 0.3g of glutaraldehyde (25% by mass aqueous solution) was added. The mixture was reacted at 45℃ in the dark for 16 hours. After freeze-drying, the mixture was pulverized and passed through a 100-mesh sieve to obtain the first polyelectrolyte complex powder. To prepare the second polyelectrolyte complex, 6g of ε-polylysine and 4g of hyaluronic acid were added to 500mL of deionized water, stirred at 35℃ for 3 hours, and then freeze-dried and pulverized through a 100-mesh sieve to obtain the second polyelectrolyte complex powder. 3g of mesoporous silica and the two composite powders mentioned above were added to a mixer and mixed evenly to obtain a biofunctional premix. The bio-based composite component consisted of 20 parts of the first polyelectrolyte composite, 10 parts of the second polyelectrolyte composite, and 3 parts of porous adsorbent material.

[0041] S2. Preparation of matrix premix: Same as in Example 1, the matrix resin component and the auxiliary component are added to a high-speed mixer to obtain the matrix premix.

[0042] S3. Low-Temperature Feeding Extrusion: The obtained matrix premix is ​​added through the main feed port in Zone 1 of the twin-screw extruder, the obtained biofunctional premix is ​​added through the side feed port in Zone 3, and the commercially available nano-silver antibacterial masterbatch and organosilicon elastic microsphere masterbatch are added through the side feed port in Zone 5. The weight proportions of the matrix resin component, auxiliary component, and commercially available functional masterbatch are the same as in Example 1. The temperatures of each zone of the twin-screw extruder are the same as in Example 1.

[0043] Example 4 The difference between Example 4 and Example 1 lies in the types of cationic polysaccharides, protein-based biopolymers, cross-linking agents, cationic antimicrobial peptides, glycosaminoglycans, and porous adsorbents. Example 4 uses quaternized chitosan and silk fibroin cross-linked with citric acid to obtain the first polyelectrolyte complex; it uses lactobacillus peptides and chondroitin sulfate to prepare the second polyelectrolyte complex; and it uses mesoporous titanium dioxide as the porous adsorbent. The mesoporous titanium dioxide in Example 4 of this application has a pore size of 2-3 nm and a specific surface area of ​​700-900 m². 2 / g.

[0044] The specific steps are as follows: S1. Preparation of biological premix: To prepare the first polyelectrolyte complex, 20g of quaternized chitosan and 10g of silk fibroin were added to 1000mL of 2wt% acetic acid aqueous solution and stirred in a water bath at 50℃ until completely dissolved. The pH was adjusted to 6.0 with 1mol / L NaOH solution, and 0.3g of citric acid was added. The mixture was reacted at 45℃ for 16 hours. After freeze-drying, the mixture was pulverized and passed through a 100-mesh sieve to obtain the first polyelectrolyte complex powder. To prepare the second polyelectrolyte complex, 6g of nisin and 4g of chondroitin sulfate were added to 500mL of deionized water, stirred at 35℃ for 3 hours, and then freeze-dried and pulverized through a 100-mesh sieve to obtain the second polyelectrolyte complex powder. 3g of mesoporous titanium dioxide and the two composite powders mentioned above were added to a mixer and mixed evenly to obtain a biofunctional premix. The bio-based composite component consists of 20 parts of the first polyelectrolyte composite, 10 parts of the second polyelectrolyte composite, and 3 parts of porous adsorbent material.

[0045] S2. Preparation of matrix premix: Same as in Example 1, add matrix resin component and auxiliary component to high-speed mixer and mix at 500 rpm for 5 minutes to obtain matrix premix.

[0046] S3. Low-Temperature Feeding Extrusion: The process parameters are the same as in Example 1. The obtained matrix premix is ​​added from the main feed port of Zone 1 of the twin-screw extruder, the obtained biofunctional premix is ​​added from the side feed port of Zone 3, and the commercially available nano-silver antibacterial masterbatch and organosilicon elastic microsphere masterbatch are added from the side feed port of Zone 5. The weight percentages of the matrix resin component, auxiliary component, and commercially available functional masterbatch are the same as in Example 1. The temperatures of each zone of the twin-screw extruder are set as follows: Zone 1 115℃, Zone 2 125℃, Zone 3 135℃, Zone 4 145℃, Zone 5 135℃, Zone 6 125℃, Zone 7 115℃, Zone 8 105℃, the screw speed is 200 rpm, and the vacuum degree is -0.07 MPa. Extrusion granulation is performed to obtain a thermoplastic elastomer.

[0047] Example 5 The difference between Example 5 and Example 1 lies in the types of cationic polysaccharides, protein-based biopolymers, cross-linking agents, glycosaminoglycans, and porous adsorbents. Example 5 uses cationic starch and soybean protein cross-linked with 1,4-butanediol diglycidyl ether to obtain the first polyelectrolyte complex; it uses ε-polylysine and heparin to prepare the second polyelectrolyte complex; and it uses mesoporous alumina as the porous adsorbent. The mesoporous alumina used in Example 5 of this application has a pore size of 2-3 nm and a specific surface area of ​​600-800 m². 2 / g.

[0048] The specific steps are as follows: S1. Preparation of biological premix: To prepare the first polyelectrolyte complex, 20g of cationic starch and 10g of soybean protein were added to 1000mL of 2wt% acetic acid aqueous solution and stirred in a water bath at 50℃ until completely dissolved. The pH was adjusted to 6.0 with 1mol / L NaOH solution, and 0.3g of 1,4-butanediol diglycidyl ether was added. The mixture was reacted at 45℃ for 16 hours. After freeze-drying, the mixture was pulverized and passed through a 100-mesh sieve to obtain the first polyelectrolyte complex powder. To prepare the second polyelectrolyte complex, 6g of ε-polylysine and 4g of heparin were added to 500mL of deionized water, stirred at 35℃ for 3 hours, and then freeze-dried and pulverized through a 100-mesh sieve to obtain the second polyelectrolyte complex powder. 3g of mesoporous alumina and the two aforementioned composite powders were added to a mixer and mixed evenly to obtain a biofunctional premix. The bio-based composite component comprises 20 parts of the first polyelectrolyte composite, 10 parts of the second polyelectrolyte composite, and 3 parts of porous adsorbent material.

[0049] S2. Preparation of matrix premix: Same as in Example 1.

[0050] S3. Low-temperature feeding extrusion: The process parameters are the same as in Example 1, and thermoplastic elastomer is obtained by extrusion granulation.

[0051] Example 6 The difference between Example 6 and Example 1 is that the cationic polysaccharide, protein-based biopolymer, cross-linking agent, cationic antimicrobial peptide, glycosaminoglycan, and porous adsorbent material are all formulated into a compound system. The specific steps are as follows: S1. Preparation of biological premix: To prepare the first polyelectrolyte complex, 10g of chitosan and 10g of quaternized chitosan were mixed, 5g of gelatin and 5g of silk fibroin were added, and the mixture was added to 1000mL of 2wt% acetic acid aqueous solution. The mixture was stirred in a water bath at 50℃ until completely dissolved. The pH was adjusted to 6.0 with 1mol / L NaOH solution. A composite crosslinking agent consisting of 0.15g of genipin and 0.15g of citric acid was added. The mixture was reacted at 45℃ in the dark for 16 hours. After freeze-drying, the mixture was pulverized and passed through a 100-mesh sieve to obtain the first polyelectrolyte complex powder. To prepare the second polyelectrolyte complex, 3g of ε-polylysine and 3g of lactobacillus peptide were mixed, along with 2g of hyaluronic acid and 2g of chondroitin sulfate. All were then added to 500mL of deionized water, stirred at 35°C for 3 hours, freeze-dried, and pulverized through a 100-mesh sieve to obtain the second polyelectrolyte complex. powder; 1.5g of mesoporous silica and 1.5g of mesoporous titanium dioxide were mixed and then added to a mixer along with the powders of the two composites mentioned above. After uniform mixing, a biofunctional premix was obtained. The bio-based composite component consisted of 20 parts of the first polyelectrolyte composite, 10 parts of the second polyelectrolyte composite, and 3 parts of porous adsorbent material.

[0052] S2. Preparation of matrix premix: Same as in Example 1.

[0053] S3. Low-temperature feeding extrusion: The process parameters are the same as in Example 1, and thermoplastic elastomer is obtained by extrusion granulation.

[0054] Example 7 The difference between Example 7 and Example 1 lies in the amount of bio-based composite component added. The specific steps are as follows: S1. Preparation of biological premix: Prepare the first polyelectrolyte complex using the same method as in Example 1 to obtain the first polyelectrolyte complex powder; Prepare the second polyelectrolyte complex using the same method as in Example 1 to obtain the second polyelectrolyte complex powder. 1g of mesoporous silica, 10g of the first polyelectrolyte complex powder, and 5g of the second polyelectrolyte complex powder were added to a mixer and mixed evenly to obtain a biofunctional premix. The bio-based composite component consists of 10 parts of the first polyelectrolyte complex, 5 parts of the second polyelectrolyte complex, and 1 part of porous adsorbent material.

[0055] S2. Preparation of matrix premix: Same as in Example 1.

[0056] S3. Low-temperature feeding extrusion: The process parameters are the same as in Example 1, and thermoplastic elastomer is obtained by extrusion granulation.

[0057] Example 8 Example 8 differs from Example 1 in that the amount of the bio-based composite component added is the upper limit of the scope of protection of the claims, verifying the processing feasibility and performance under high addition levels. The specific steps are as follows: S1. Preparation of biological premix: Prepare the first polyelectrolyte complex using the same method as in Example 1 to obtain the first polyelectrolyte complex powder; Prepare the second polyelectrolyte complex using the same method as in Example 1 to obtain the second polyelectrolyte complex powder. 8g of mesoporous silica, 30g of the first polyelectrolyte complex powder, and 20g of the second polyelectrolyte complex powder were added to a mixer and mixed evenly to obtain a biofunctional premix. The bio-based composite component consisted of 30 parts of the first polyelectrolyte complex, 20 parts of the second polyelectrolyte complex, and 8 parts of porous adsorbent material.

[0058] S2. Preparation of matrix premix: Same as in Example 1.

[0059] S3. Low-temperature feeding extrusion: The process parameters are the same as in Example 1, and thermoplastic elastomer is obtained by extrusion granulation.

[0060] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that electrostatic composite and cross-linking reactions were not performed. Instead, the bioactive components were directly physically mixed and added to the matrix to verify the technical necessity of the polyelectrolyte complex structure. The specific steps are as follows: S1. Preparation of biological premix: Add 20g chitosan, 10g gelatin, 6g ε-polylysine, 4g hyaluronic acid, and 3g mesoporous silica directly to a mixer and mix evenly to obtain biological premix.

[0061] S2. Preparation of matrix premix: Same as in Example 1.

[0062] S3. Extrusion process: Same as in Example 1, extrusion granulation is used to obtain the comparative thermoplastic elastomer.

[0063] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that no porous adsorbent material was added, while the other components and processes were the same as in Example 1, verifying the synergistic effect of the porous adsorbent material and the polyelectrolyte complex.

[0064] S1. Preparation of biological premix: The method for preparing the first polyelectrolyte complex and the second polyelectrolyte complex is the same as in Example 1. The two complex powders are added to a mixer and mixed evenly to obtain the biological functional premix. S2. Preparation of matrix premix: Same as in Example 1; S3, Low-temperature feeding extrusion: The process parameters are the same as in Example 1, and the comparative thermoplastic elastomer is obtained by extrusion granulation.

[0065] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that a conventional high-temperature extrusion process was used, with all materials fed together from the main feed port, instead of a low-temperature multi-segment side-feeding scheme, to verify the protective effect of the low-temperature processing technology on bioactive components. The specific extrusion temperatures were set as follows: Zone 1 150℃, Zone 2 170℃, Zone 3 190℃, Zone 4 190℃, Zone 5 180℃, Zone 6 170℃, Zone 7 160℃, and Zone 8 150℃; the remaining raw material ratios were the same as in Example 1.

[0066] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that no bio-based composite components (first polyelectrolyte complex, second polyelectrolyte complex, porous adsorbent material) were added. The antibacterial and slip-feeling functions were achieved solely through commercially available functional masterbatch, verifying the core gain of the bio-based composite system. The remaining matrix and auxiliary components were the same as in Example 1.

[0067] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that no crosslinking agent was added during the preparation of the first polyelectrolyte composite; the composite was formed solely through electrostatic interactions without covalent crosslinking, thus verifying the effect of the crosslinking reaction on improving structural stability. All other processes and components were the same as in Example 1.

[0068] Performance Testing and Result Analysis The thermoplastic elastomer materials prepared in Examples 1-8 and Comparative Examples 1-5 were added to the SEBS blank matrix at an addition amount of 8 wt%, and standard test strips were prepared by low-temperature injection molding. The performance was tested according to the following standards, and the test results are shown in Table 1 below.

[0069] 1. Sweat Resistance Test: The original tensile strength of the test specimens was tested according to GB / T1040.1-2018. The specimens were immersed in artificial sweat. After being kept at 37℃ for 72 hours, the specimens were removed, washed, dried, and the tensile strength was tested again. The tensile strength retention rate was calculated. The artificial sweat was prepared according to GB / T39605-2020, with the following composition: sodium chloride 20g / L, lactic acid 1.5g / L, urea 1.5g / L, and the pH was adjusted to 5.5±0.1 with sodium hydroxide.

[0070] 2. TVOC content test: Refer to GB / T39598-2020 and use headspace gas chromatography to test the total volatile organic compound content of the sample.

[0071] 3. Antibacterial performance test: Refer to GB / T31402-2015 to test the antibacterial rate of the sample against Staphylococcus aureus (ATCC6538) and Escherichia coli (ATCC8739).

[0072] 4. Moisturizing performance test: The test environment is a temperature of 22±2℃ and a relative humidity of 50±5%. The test area should not be exposed to skin care products and chemicals within 24 hours before the test. During the test, the baseline value of the stratum corneum moisture content of the blank area should be measured first. After wearing the sample for 2 hours, the moisture content of the same area should be measured again. The moisture content increase rate should be calculated and the average value should be taken.

[0073] 5. Skin irritation test: New Zealand white rabbits were used for the skin patch test. Six parallel animals were set up in each group. Erythema and edema were scored according to GB / T16886.10-2017 standard, and the average skin irritation index was calculated.

[0074] All the above performance tests were performed with 5 parallel samples. The test results were averaged and the relative deviation of the parallel samples was ≤5%.

[0075] Table 1, Performance Test Tables of Examples 1-8 and Comparative Examples 1-5

[0076] As can be seen from the performance test results in the table above, the thermoplastic elastomer materials prepared in Examples 1-8 of this invention, after being added to the downstream matrix in proportion and molded, all meet the technical indicators defined in the claims of this invention, namely, the tensile strength retention rate after soaking in artificial sweat for 72 hours is ≥80%, the TVOC content is ≤50μg / g, the antibacterial rate against Staphylococcus aureus and Escherichia coli is ≥99%, the stratum corneum moisture content is increased by ≥15%, and the skin irritation index is ≤1.0 grade, which fully verifies the stability and feasibility of the technical solution of this invention.

[0077] Analysis of Example 1 and Comparative Example 1 showed that Comparative Example 1, without preparing a polyelectrolyte complex, only directly physically blended the bioactive components. Its sweat resistance, antibacterial properties, and moisturizing properties all decreased significantly, while its TVOC content and skin irritation index increased substantially. This demonstrates that the electrostatic assembly of cationic polysaccharides and protein-based biopolymers, and cationic antibacterial peptides and glycosaminoglycans to form polyelectrolyte complexes, is the core structural basis for achieving stable loading of biological components and preventing migration and precipitation. In Comparative Example 5, the first polyelectrolyte complex was prepared without adding a cross-linking agent, relying solely on electrostatic interactions. Its properties decreased significantly compared to Example 1, but were still superior to those of Comparative Example 1, which involved direct physical blending. This demonstrates that cross-linking reactions can form covalent cross-linked networks based on electrostatic complexation, improving the thermal stability and sweat dissociation resistance of the complex.

[0078] In contrast, Comparative Example 2, which did not contain porous adsorbent material, showed a moderate decrease in its sweat resistance, TVOC control, and antibacterial properties. This demonstrates that porous adsorbent material can form an anti-sweat barrier through physical retention and capillary coagulation, along with the chemical chelation of the polyelectrolyte complex. The synergistic effect of these two processes significantly improves the material's anti-sweat and low-excretion effect.

[0079] In addition, Comparative Example 3, which used a conventional high-temperature extrusion process with all materials fed together from the main feed port, showed a significant decrease in its bioactivity-related properties, with the highest TVOC content and skin irritation index among all samples. This demonstrates that the low-temperature processing window and zoned side-feeding strategy of this invention can effectively avoid the thermal degradation and inactivation of heat-sensitive biological components, and is a key process guarantee for ensuring the activity of biological functional components and achieving the expected technical effects.

[0080] Finally, Comparative Example 4, which used only commercially available functional masterbatch without adding bio-based composite components, showed significantly inferior moisturizing performance, sweat resistance, and low VOC levels compared to the examples. This demonstrates that the bio-based composite system of this invention is the core source for achieving deep skin-friendly moisturizing, long-lasting sweat resistance, and high biocompatibility. Relying solely on traditional commercially available functional masterbatches cannot solve the core pain points of existing technologies.

[0081] In addition, Examples 1-6 were prepared using different cationic polysaccharides, protein-based biopolymers, cross-linking agents, cationic antibacterial peptides, glycosaminoglycans, and porous adsorbents, with Example 6 employing a multi-component compound system. Experimental results show that, whether selected individually or in a reasonable compound, the above raw materials can stably achieve the expected antiperspirant, antibacterial, moisturizing, and low-irritant effects, with only slight performance fluctuations due to differences in the activity of each raw material. Furthermore, the multi-component compound system can further exert a synergistic effect, demonstrating that the range of raw material selection defined in the claims of this invention is sufficiently feasible and consistent in its effects.

[0082] Furthermore, Examples 7 and 8 used different proportions of the bio-based composite components. The results showed that within the proportion range defined by this invention, the anti-sweat, antibacterial, and moisturizing properties of the material increased positively with increasing amounts of the bio-based composite components. Additionally, the weight range of the matrix resins defined in this application is a conventional blending range for styrene-based thermoplastic elastomers, belonging to well-known and mature formulation systems in the art. Adjusting the proportions of each matrix resin within this range only has a linear, conventional effect on the material's basic mechanical properties such as hardness, tensile modulus, and elongation at break; it does not disrupt the dispersion state of the bio-based composite components in the matrix, nor does it affect their mechanism of enrichment on the material surface and their functional action. The lower limit of the proportion ensures that the matrix possesses adequate elasticity and melt processing fluidity, while the upper limit still provides a stable dispersion medium for the biofunctional components; neither will have a drastic impact on the core performance indicators.

[0083] The experimental results above indicate that, in terms of low sweat release and antiperspirant properties, the physical retention of the porous adsorbent material and the chemical chelation of the polyelectrolyte complex form a barrier, preventing small sweat molecules from penetrating inward and damaging the matrix, while also inhibiting the outward migration and release of internal additives, thus achieving sweat resistance stability and low TVOC release. Regarding long-lasting antibacterial effects, the cationic antibacterial peptides of the second polyelectrolyte complex achieve contact sterilization, while the first polyelectrolyte complex disrupts the bacterial growth environment by chelating sweat nutrients. Combined with the inorganic antibacterial components of the functional masterbatch, this addresses the problems of easy loss and short-lasting effectiveness of traditional single antibacterial agents.

[0084] In terms of skin-friendly moisturizing, glycosaminoglycans construct a bio-hydration layer on the material surface to achieve deep moisturizing. Combined with their low-exudation properties, this avoids skin irritation from small-molecule additives, resulting in a highly moisturizing and low-irritation skin-friendly effect. Furthermore, the cross-linked, stable polyelectrolyte structure, along with the low-temperature side-feeding process, achieves a balance between functional activity and processing feasibility.

[0085] Among commercially available functional masterbatches, nano-silver, zinc oxide, and titanium dioxide are all inorganic antibacterial agents. Their antibacterial mechanism involves the slow release of metal ions or photocatalysis to disrupt the bacterial cell membrane and protein structure, achieving broad-spectrum antibacterial activity. These inorganic antibacterial masterbatches all use polyolefin resin as a carrier and exhibit consistent dispersion compatibility within the styrene-based elastomer matrix of this invention. They can all serve as auxiliary antibacterial components to form a synergistic effect with the bio-based composite antibacterial system. Organosilicon elastic microsphere masterbatches are used to reduce the surface friction coefficient of materials and improve the smooth feel. Their polysiloxane structure is compatible with the matrix resin and is a conventional smoothing functional component in the field.

[0086] Maleic anhydride-grafted polyolefin compatibilizers have a nonpolar polyolefin backbone at one end of their molecular structure, exhibiting good structural similarity and compatibility with components such as polypropylene, polyethylene, and polycaprolactone in the matrix. The other end contains maleic anhydride active functional groups, which can chemically bond with the amino and hydroxyl groups on the surface of bio-based composite components, thereby enhancing the interfacial bonding force between polar biological components and the nonpolar elastomer matrix and reducing component migration and precipitation. The mechanisms of action of maleic anhydride-grafted polylactic acid, maleic anhydride-grafted polypropylene, and maleic anhydride-grafted polyethylene are completely consistent, with only minor conventional effects on interfacial bonding strength due to differences in backbone structure. They are interchangeable conventional compatibilizers in the field, and all can stably achieve compatibility effects within the dosage range specified in this invention.

[0087] Furthermore, this invention also provides applications of the aforementioned thermoplastic elastomer materials. These materials are used to manufacture watch straps, wristbands, skin-touch sensor housings, or contact components for AR / VR devices in smart wearable devices. Specifically, the thermoplastic elastomer materials require a low-temperature injection molding process during downstream injection molding, with the barrel temperature controlled within the range of 110-140°C. This application feature is designed to match the thermal stability threshold of the biofunctional components, preventing thermal degradation of ε-polylysine, hyaluronic acid, and genipin crosslinking structures during processing, thereby ensuring the long-term effectiveness of the final product in terms of sweat resistance, antibacterial properties, and moisturizing.

[0088] Specifically, when injection molding downstream products, the recommended barrel temperature settings are as follows: rear section (feeding zone): 120-140℃; middle section (compression zone): 140-160℃; front section (metering zone): 150-170℃; nozzle: 140-160℃; mold temperature: 30-60℃. During downstream product injection molding, the processing temperature should not exceed 180℃. If the processing temperature of ordinary TPE (i.e., 190-210℃) is used, although the matrix can still be molded, ε-polylysine may begin to degrade, and the antibacterial rate will drop rapidly.

[0089] Regarding time control, it is necessary to reduce the heat residence time. It is recommended that the amount of molten plastic injected each time account for 40%-80% of the injection molding machine's barrel capacity. Minimize the molding cycle and reduce the total residence time of the material in the barrel. Furthermore, avoid prolonged shutdowns. If the shutdown exceeds 15 minutes, the material in the barrel must be emptied or cleaned with PP material to prevent the material from being heated and carbonized within the screw for an extended period.

[0090] In terms of shear control, to reduce shear heat, low back pressure (5-10 bar) operation is used as much as possible to reduce frictional heat generation of the melt in the screw. The screw speed is kept at medium to low speed (50-80 rpm) to avoid excessive local temperature caused by shear heat generated by high-speed rotation. Furthermore, the nozzle orifice size is controlled to minimize the shear heat generated by excessive injection pressure.

[0091] In addition, if ordinary TPE or ABS is used before injection molding, the barrel must be thoroughly cleaned with PP or PE until the ejected strip is free of impurities and black spots. It is strictly forbidden to directly mix the thermoplastic elastomer masterbatch of this application with ordinary TPE powder, and it must be added to clean SEBS-based blank material in proportion (2-15wt%).

[0092] Furthermore, analysis of Examples 7 and 8 above shows that the amount of bio-based composite component added increases positively with the material's anti-sweat, antibacterial, and moisturizing properties, with no performance degradation inflection point within the test range. This pattern also applies to downstream matrix dilution addition scenarios. When the addition amount is 2wt%, sufficient component concentration can be formed on the product surface based on the surface enrichment effect, thus meeting certain performance indicators. When the addition amount is 15wt%, the functional components can still be uniformly dispersed in the downstream matrix without aggregation or surface precipitation, resulting in good processing performance. Moreover, the core functions are further optimized with increasing addition amount. Based on the mechanism of action disclosed in this application and the performance trends presented in the examples, it is reasonably expected that the expected technical effects of this invention can be stably achieved within the downstream addition amount range of 2-15wt%.

[0093] On the other hand, smart wearable device straps or contact parts made using the thermoplastic elastomer material of this invention exhibit excellent stain resistance and ease of maintenance in daily use. When the surface becomes stained with dust or sweat, simply rinse with water or neutral soapy water, then wipe dry with a soft cloth. Thanks to the low surface energy and hydrophobicity of the material, water droplets cannot penetrate, and stains are easily removed. Do not use organic solvents such as alcohol, gasoline, or acetone to wipe the surface, as this may damage the hyaluronic acid hydration layer and polyelectrolyte complex structure.

[0094] In addition, because the antibacterial mechanism is non-release and the anti-sweat barrier has a dual physical and chemical structure, the antibacterial rate, moisturizing rate and anti-sweat performance of this product do not significantly decrease within 2-3 years under normal wearing and cleaning conditions.

[0095] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments have been described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than those shown in the embodiments and still achieve the desired results. In some implementations, multitasking and parallel processing are also possible or may be advantageous.

[0096] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

[0097] This specification is merely an illustrative description of this application and is intended to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Therefore, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.

Claims

1. A method for preparing a thermoplastic elastomer material, characterized in that, Includes the following steps: S1. Preparation of biological premix: Cationic polysaccharides and protein-based biopolymers are mixed in an acidic aqueous solution at a certain mass ratio, and after adjusting the pH, a cross-linking agent is added for cross-linking. After freeze-drying and pulverizing, the first polyelectrolyte complex powder is obtained. Cationic antibacterial peptides and glycosaminoglycans are added to deionized water at a certain mass ratio and stirred to form a second polyelectrolyte complex. After freeze-drying and pulverizing, the second polyelectrolyte complex powder is obtained. The porous adsorbent material is mixed evenly with the above two complex powders to obtain a biological functional premix. S2. Preparation of matrix premix: Hydrogenated styrene-butadiene-styrene block copolymer, styrene-butadiene-styrene block copolymer, polypropylene, polyethylene, polycaprolactone, compatibilizer, calcium carbonate, antioxidant, lubricant and VOC scavenger are added to a mixer and mixed evenly to obtain matrix premix; S3, Low-temperature feeding extrusion: The matrix premix obtained in step S2 is added from the main feed port of the twin-screw extruder, the biofunctional premix obtained in step S1 is added from the upstream side feed port of the twin-screw extruder, and the commercially available functional masterbatch is added from the side feed port of the twin-screw extruder near the die head. Finally, the thermoplastic elastomer material is extruded.

2. The method for preparing the thermoplastic elastomer material according to claim 1, characterized in that, In step S1, the cationic polysaccharide is selected from one or more of chitosan, carboxymethyl chitosan, quaternized chitosan, and cationic starch; the protein-based biopolymer is selected from one or more of gelatin, collagen, silk fibroin, and soy protein.

3. The method for preparing the thermoplastic elastomer material according to claim 2, characterized in that, In step S1, the crosslinking agent is selected from one or more of genipin, glutaraldehyde, citric acid, and 1,4-butanediol diglycidyl ether; the cationic polysaccharide and the protein-based biopolymer form a polyelectrolyte complex through electrostatic interaction and crosslinking reaction.

4. The method for preparing the thermoplastic elastomer material according to claim 1, characterized in that, In step S1, the cationic antimicrobial polypeptide is selected from one or more of ε-polylysine and lactobacillus peptide; the glycosaminoglycan is selected from one or more of hyaluronic acid, chondroitin sulfate, and heparin.

5. The method for preparing the thermoplastic elastomer material according to claim 1, characterized in that, The porous adsorbent material in the S1 step is selected from one or more of mesoporous silica, mesoporous titania, mesoporous alumina, having a pore size of 2-3 nm and a specific surface area of 600-1200 m 2 / g.

6. The method for preparing the thermoplastic elastomer material according to claim 1, characterized in that, In step S3, the temperature settings for each zone of the twin-screw extruder are as follows: Zone 1 100-130℃, Zone 2 110-140℃, Zone 3 120-150℃, Zone 4 130-160℃, Zone 5 130-160℃, Zone 6 120-150℃, Zone 7 110-140℃, and Zone 8 100-130℃; the screw speed is 100-400 rpm, and the vacuum degree is -0.08 to -0.04 MPa.

7. The method for preparing the thermoplastic elastomer material according to claim 1, characterized in that, The commercially available functional masterbatch in step S3 includes one or more of the following: nano-silver antibacterial masterbatch, organosilicon elastic microsphere masterbatch, zinc oxide antibacterial masterbatch, and titanium dioxide antibacterial masterbatch; the compatibilizer is selected from one or more of the following: maleic anhydride-grafted polylactic acid, maleic anhydride-grafted polypropylene, and maleic anhydride-grafted polyethylene.

8. A thermoplastic elastomer material prepared using the preparation method of the thermoplastic elastomer material according to any one of claims 1 to 7, characterized in that, By weight, it includes the following components: Matrix resin composition: 15-30 parts of hydrogenated styrene-butadiene-styrene block copolymer, 5-20 parts of styrene-butadiene-styrene block copolymer, 10-25 parts of polypropylene, 10-25 parts of polyethylene, and 3-15 parts of polycaprolactone. Bio-based composite components: 10-30 parts of the first polyelectrolyte complex, 5-20 parts of the second polyelectrolyte complex, and 1-8 parts of porous adsorbent material; Additive components: 2-10 parts compatibilizer, 5-20 parts calcium carbonate, 0.3-2.0 parts antioxidant, 0.1-1.5 parts lubricant, 0.3-3.0 parts VOC scavenger; Commercially available functional masterbatches: 1-5 parts of antibacterial masterbatch and 3-12 parts of smoothing masterbatch.

9. The thermoplastic elastomer material according to claim 8, characterized in that, The thermoplastic elastomer material is added to the downstream thermoplastic elastomer matrix at a rate of 2-15 wt%, and the resulting product after injection molding or extrusion molding meets the following performance requirements: The tensile strength retention rate after 72 hours of artificial sweat immersion is greater than or equal to 80%, the TVOC content is less than or equal to 50 μg / g, the antibacterial rate against Staphylococcus aureus and Escherichia coli is greater than or equal to 99%, and the stratum corneum moisture content is increased by greater than or equal to 15%.

10. An application of the thermoplastic elastomer material according to claim 8 or 9, characterized in that, The thermoplastic elastomer material is used to prepare watch straps, wristbands, skin-contact sensor shells, or AR / VR device contact components for smart wearable devices. When the smart wearable device is worn close to the skin for a long time, the skin irritation index of its contact surface is less than or equal to 1.0.

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