Conductive latex, method for its preparation and use in safety gloves
By using urea-intercalated zinc-modified MXenes hybrid conductive filler and composite dispersant, the compatibility problem between conductive materials and matrix materials in work gloves was solved, achieving uniformity of conductivity and improvement of mechanical properties, thus meeting the requirements of wearing comfort and durability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANDONG JINGYUANJI LABOR PROTECTION PROD CO LTD
- Filing Date
- 2025-12-08
- Publication Date
- 2026-07-03
AI Technical Summary
The existing work gloves have poor compatibility between the conductive material and the base material, resulting in uneven conductivity, high cost, and insufficient wearing comfort.
The MXene hybrid conductive filler Urea-Zn-MXene, modified by urea intercalation and zinc, was combined with a composite dispersant of lignin sulfonate and polyoxyethylene ether surfactants to optimize the dispersibility of the conductive filler in latex. The processing performance and mechanical properties of the latex were improved by adjusting the proportion of additives.
This technology achieves uniform conductivity of conductive latex in work gloves, improving the gloves' softness and comfort while enhancing their mechanical properties and abrasion resistance, thus meeting practical usage requirements.
Smart Images
Figure CN121343255B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of work gloves material technology, specifically relating to a conductive latex, its preparation method, and its application in work gloves. Background Technology
[0002] With increasing emphasis on occupational safety, gloves are now worn in almost all work activities. Safety gloves include several types, such as rubber gloves, plastic gloves, and latex gloves. Currently, with the increasing functionality and diversity of electronic products and devices, more and more electronic devices are equipped with touch panels. Users of these devices can input information by touching the touch panel with their fingers or other parts such as a stylus. Touch panels can be operated using methods such as resistance pressure, capacitance, and infrared. However, when users touch the touch panel with ordinary gloves such as leather gloves, woven gloves made of fiber fabric, or knitted gloves made of yarn, the touch panel will not activate because these gloves are non-conductive. Therefore, it is inconvenient to use smartphones or operate electronic devices only after removing the gloves. Thus, how to operate electronic devices sensitively and conveniently while wearing gloves has become a research hotspot.
[0003] Currently, there are several main ways to solve the touchscreen problem in gloves on the market: one is to add conductive wires to the glove blank, either entirely or partially, to increase the conductivity of the dipped glove; another is to add conductive fillers to the rubber to increase its conductivity; and yet another is to use a process that allows for partial finger conductivity to prevent the glove's performance from being reduced by the conductive fillers. Each type of conductive glove has its own advantages and disadvantages. Adding conductive wires to the glove blank provides good conductivity, but it is expensive; adding conductive fillers to the rubber can reduce the price, but the addition of conductive fillers makes the glove stiff, less durable, and less comfortable.
[0004] For example, CN110982134A discloses a rubber glove with conductive touchscreen function, including a glove body, the outer surface of which is provided with a conductive layer; the glove body is made of rubber base and conductive solution in a weight ratio of 90:10; the conductive layer is made of conductive solution; the raw materials of the conductive solution include, by weight, 20-30 parts of sodium polyacrylate, 20-30 parts of carboxymethyl cellulose, and 45-55 parts of water; ensuring that users can flexibly operate touchscreen mobile phones and touchscreen computers while wearing gloves. CN107936318A discloses an antistatic, high-cleanliness latex glove. Its raw materials, by weight, include: 50-80 parts natural latex; 0.1-0.5 parts accelerator ZDC; 0.1-2 parts sulfur; 0.5-2 parts zinc oxide; 0.1-0.3 parts antioxidant; 0.5-1 parts potassium hydroxide; 0.1-0.3 parts lanolin; 1-2 parts conductive material; and 1-2 parts defoamer. The beneficial effects of this latex are mainly reflected in the addition of a conductive material composed of lithium manganese oxide particles and a porous three-dimensional carbon skeleton structure to the formulation of the latex glove, resulting in better conductivity and antistatic properties. However, the conductive materials and rubber materials in the conductive rubber gloves prepared by these two methods have poor compatibility, leading to poor dispersion of the conductive solution in the rubber body. Consequently, the conductivity of different parts of the rubber glove is uneven, easily resulting in some parts of the glove being non-conductive during use, causing inconvenience to the user.
[0005] Therefore, there is an urgent need to develop a touchscreen work gloves that have stable conductivity, moderate cost, comfortable wear, and uniform conductivity in all parts. Summary of the Invention
[0006] This invention addresses the problems of existing technologies by providing a conductive latex, its preparation method, and its application in work gloves. This solves the issues of poor compatibility between conductive materials and matrix materials, uneven conductivity, and high cost in existing technologies. By optimizing the type and preparation process of conductive fillers, this invention significantly improves the dispersibility and stability of conductive fillers in the latex, thereby ensuring uniform conductivity during application. Furthermore, by rationally adjusting the proportions of various additives in the formulation, this invention further improves the processing performance of the latex and the mechanical properties of the final product. This results in conductive work gloves that not only possess good conductivity but also softness and comfort, meeting practical usage requirements.
[0007] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:
[0008] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3-8 parts of conductive filler, 1-3 parts of composite dispersant, 0.5-2 parts of vulcanizing agent, 0.5-2 parts of stabilizer, 0.5-1.5 parts of accelerator, 0.5-1.5 parts of antioxidant, and 1-5 parts of thickener.
[0009] Furthermore, the solid content of the natural latex is 50-65%.
[0010] Furthermore, the conductive filler is a urea-intercalated zinc-modified MXenes hybrid conductive filler, Urea-Zn-MXene, and the specific preparation method is as follows:
[0011] (1) Urea-assisted etching-intercalation stripping: Weigh 1g Ti3AlC2 powder and 1g LiF, add 20mL of 9M HCl and react at 33-35℃ for 24h; centrifuge and wash until the pH of the supernatant is 5-6 to obtain multilayer Ti3C2Tx precipitate; add 50mL of saturated urea aqueous solution per gram of precipitate, stir at 40-50℃ for 12h, sonicate at 300-500W power for 1-2h in an ice bath, then centrifuge at 8000rpm for 20min, collect the upper black-green colloidal dispersion Urea-MXene and determine its solid content;
[0012] (2) In-situ modification: Take a Urea-MXene dispersion containing 0.1g MXene solid, add 1.2-1.8mL of 0.1M zinc salt aqueous solution dropwise under mechanical stirring, and stir at room temperature for 2 hours to adsorb; slowly add dilute ammonia water to adjust the pH to 8.5-9.0, continue stirring for 1 hour, centrifuge, and wash the precipitate 2-3 times with deionized water to remove free ions and urea;
[0013] (3) Post-treatment: The washed precipitate was vacuum dried at 60-80℃, and then gently ground to obtain urea-Zn-MXene hybrid conductive filler.
[0014] The conductive filler Urea-Zn-MXene has a particle size of 1-5 μm.
[0015] Furthermore, the zinc salt is one of zinc acetate, zinc sulfate, or zinc chloride.
[0016] Furthermore, the composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:1.
[0017] Furthermore, the lignin sulfonate is sodium lignin sulfonate or calcium lignin sulfonate; the polyoxyethylene ether surfactant is alkylphenol polyoxyethylene ether or fatty alcohol polyoxyethylene ether.
[0018] Furthermore, the vulcanizing agent is sulfur and zinc oxide in a mass ratio of 1:(2-4); the stabilizer is a mixture of potassium hydroxide and casein, wherein the mass ratio of potassium hydroxide to casein is 1:(0.5-2).
[0019] Furthermore, the accelerator is at least one of tetramethylthiuram disulfide or 2-mercaptobenzothiazole, the antioxidant is one of N-phenyl-β-naphthylamine or 2,6-di-tert-butyl-p-cresol, and the thickener is sodium carboxymethyl cellulose.
[0020] A method for preparing a conductive latex, comprising the following steps:
[0021] a. Preparation of conductive filler slurry: 3-8 parts of the urea intercalated-zinc modified MXenes hybrid conductive filler are mixed with 1-3 parts of composite dispersant and 20-40 parts of deionized water, and then subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate is 8000-12000 rpm, the ultrasonic power is 200-400W, and the treatment time is 30-60 minutes;
[0022] b. Pretreatment of latex matrix: Mix 100 parts of natural latex (dry weight) and 0.5-2 parts of stabilizer at 30-50℃ for 1-2 hours for curing treatment;
[0023] c. Composite and Vulcanization: Slowly add the conductive filler slurry prepared in step a to the pretreated latex matrix in step b, and stir until homogeneous. Then add 0.5-2 parts of vulcanizing agent, 0.5-1.5 parts of accelerator, and 0.5-1.5 parts of antioxidant. Perform a pre-vulcanization reaction at 40-50℃ until the desired chloroform value is reached. Maintaining a chloroform value of 40-50 ensures that the latex has sufficient fluidity to guarantee uniform coating, while also possessing a certain degree of cross-linking to fix the conductive filler. Subsequent vulcanization can further refine the cross-linking structure, balancing mechanical properties and conductivity.
[0024] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 1-5 parts of thickener to adjust the viscosity, and obtain the conductive latex.
[0025] A conductive latex glove comprises a conductive latex as described in any one of claims 1 to 8 and a glove blank; the conductive latex layer is firmly adhered to the surface of the glove blank by immersing the glove blank in the conductive latex for coating, followed by drying and vulcanization molding processes. The coating thickness is controlled to be 0.1-0.3 mm.
[0026] All raw materials used in this invention are commercially available.
[0027] Compared with existing technologies, the beneficial effects are:
[0028] 1. A highly efficient three-dimensional conductive network based on two-dimensional sheets was constructed to achieve uniform and stable touch performance. The Urea-Zn-MXene conductive filler used in this invention is a two-dimensional MXene nanosheet that has undergone urea intercalation and zinc modification. Its unique two-dimensional sheet structure can fully expand and highly disperse in the latex system, and through surface-to-surface contact, it can overlap with each other at low addition amounts (3-8 parts) to form a continuous, dense, and highly redundant three-dimensional conductive network. Compared with zero-dimensional (particle) or one-dimensional (fiber) conductive fillers, this network structure has a lower percolation threshold and better charge transport efficiency. The matching composite dispersant (a mixture of lignin sulfonate and polyoxyethylene ether in equal proportions) plays a key role: the benzene ring structure of lignin sulfonate can be strongly adsorbed onto the surface of MXene sheets through π-π interactions, providing an anchoring effect; while the long chains of polyoxyethylene ether extend into the aqueous phase, preventing the re-aggregation between sheets through a strong steric hindrance effect. The synergy of these two elements ensures the long-term stable dispersion of two-dimensional MXenes nanosheets in the latex in a monolayer or few-layer state, fundamentally eliminating the problem of uneven conductivity caused by filler agglomeration, and stabilizing the surface resistivity of the resulting glove at 10 Ω·cm. 4 -10 5 Within the Ω range, and with minimal resistance deviation in different parts, the touchscreen operation is sensitive and reliable.
[0029] 2. This invention achieves triple synergistic reinforcement of "filler-dispersant-matrix," significantly improving overall mechanical properties and durability. The two-dimensional MXenes sheets of this invention possess extremely high mechanical strength. The surface-modified zinc compounds (such as Zn(OH)2 or ZnO) can act as active sites for rubber vulcanization, forming chemical bonds or strong physical adsorption with latex molecular chains, greatly enhancing the interfacial bonding force between the filler and the rubber matrix. This allows the MXenes sheets to effectively bear and transfer stress, acting as a reinforcing agent similar to "nano-steel bars," significantly improving the tensile strength, tear strength, and modulus of the film.
[0030] 3. Synergistic Dispersion and Structural Stability: While stabilizing the dispersion of MXenes, the composite dispersant's hydrophilic segments also improve the compatibility of the entire system with water-based latex, reducing phase separation. This highly uniform and firmly bonded microstructure allows for uniform stress distribution when the film is subjected to friction, puncture, or bending, minimizing stress concentration points. This synergistically enhances the product's abrasion resistance, puncture resistance, and flexural fatigue resistance, achieving high-level durability of gloves that meet relevant protective standards such as EN 388 and EN 407.
[0031] 4. In addition, the MXenes sheets and their zinc-modified surface layer provide some barrier properties against moisture and oxygen. The tightly stacked sheet structure creates tortuous paths within the film, slowing the penetration of corrosive media. The zinc compound also provides some cathodic protection. This enhances the glove's corrosion and chemical resistance, broadening its application scenarios.
[0032] 5. In summary, this invention successfully prepared a high-performance conductive latex by utilizing the multi-scale and multi-mechanism synergistic effect between two-dimensional Urea-Zn-MXene sheets, a specially formulated composite dispersant, and a natural latex matrix. This material not only solves the core problem of uniform conductivity in touch gloves, but also simultaneously achieves a comprehensive leap forward in multiple protective properties such as mechanical strength, abrasion resistance, puncture resistance, and corrosion resistance, and has significant industrial application value. Attached Figure Description
[0033] Figure 1 This is a scanning electron microscope image of the Urea-Zn-MXene conductive filler particles obtained in Example 1 of the present invention.
[0034] Figure 2 This is a scanning electron microscope image of the surface of the conductive filler Urea-Zn-MXene particles obtained in Example 1 of the present invention. Detailed Implementation
[0035] The technical solution of the present invention will be further described below with reference to specific embodiments, but it is not limited thereto.
[0036] Example 1
[0037] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3 parts of conductive filler, 1 part of composite dispersant, 0.5 parts of vulcanizing agent, 0.5 parts of stabilizer, 0.5 parts of accelerator, 0.5 parts of antioxidant, and 5 parts of thickener.
[0038] The solid content of the natural latex is 50-65%.
[0039] The conductive filler is a urea-intercalated zinc-modified MXene hybrid conductive filler, Urea-Zn-MXene, prepared by the following method:
[0040] (1) Urea-assisted etching-intercalation stripping: Weigh 1g Ti3AlC2 powder and 1g LiF, add 20mL of 9M HCl and react at 33-35℃ for 24h; centrifuge and wash until the pH of the supernatant is 5-6 to obtain multilayer Ti3C2Tx precipitate; add 50mL of saturated urea aqueous solution per gram of precipitate, stir at 40-50℃ for 12h, sonicate at 300W power for 1h in an ice bath, then centrifuge at 8000rpm for 20min, collect the upper black-green colloidal dispersion Urea-MXene and determine its solid content;
[0041] (2) In-situ modification: Take a Urea-MXene dispersion containing 0.1g MXene solid, add 1.2mL of 0.1M zinc salt aqueous solution dropwise under mechanical stirring, and stir at room temperature for 2 hours to adsorb; slowly add dilute ammonia water to adjust the pH to 8.5-9.0, continue stirring for 1 hour, centrifuge, and wash the precipitate 2-3 times with deionized water to remove free ions and urea;
[0042] (3) Post-treatment: The washed precipitate was vacuum dried at 60-80℃, and then gently ground to obtain urea-intercalated zinc-modified MXene hybrid conductive filler Urea-Zn-MXene. The particle size of the conductive filler Urea-Zn-MXene was 1-5μm.
[0043] The zinc salt is zinc acetate.
[0044] The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:1.
[0045] The lignin sulfonate is sodium lignin sulfonate; the polyoxyethylene ether surfactant is alkylphenol polyoxyethylene ether.
[0046] The vulcanizing agent is sulfur and zinc oxide in a mass ratio of 1:2; the stabilizer is a mixture of potassium hydroxide and casein in a mass ratio of 1:0.5.
[0047] The accelerator is tetramethylthiuram disulfide, the antioxidant is N-phenyl-β-naphthylamine, and the thickener is sodium carboxymethyl cellulose.
[0048] A method for preparing a conductive latex, comprising the following steps:
[0049] a. Preparation of conductive filler slurry: 3 parts of the urea intercalated-zinc modified MXenes hybrid conductive filler were mixed with 1 part of composite dispersant and 20 parts of deionized water, and subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate was 8000 rpm, the ultrasonic power was 200 W, and the treatment time was 30 minutes.
[0050] b. Pretreatment of latex matrix: Mix 100 parts of natural latex (dry weight) and 0.5 parts of stabilizer at 30-50℃ for 1 hour for curing treatment;
[0051] c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 0.5 parts of vulcanizing agent, 0.5 parts of accelerator, and 0.5 parts of antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; the chloroform value is controlled at 40-50.
[0052] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 5 parts of thickener to adjust the viscosity, and obtain the conductive latex.
[0053] Example 2
[0054] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 4 parts of conductive filler, 2 parts of composite dispersant, 1 part of vulcanizing agent, 1.5 parts of stabilizer, 1 part of accelerator, 1 part of antioxidant, and 2 parts of thickener.
[0055] The solid content of the natural latex is 50-65%.
[0056] The conductive filler is a urea-intercalated zinc-modified MXene hybrid conductive filler, Urea-Zn-MXene, prepared by the following method:
[0057] (1) Urea-assisted etching-intercalation stripping: Weigh 1g Ti3AlC2 powder and 1g LiF, add 20mL of 9M HCl and react at 33-35℃ for 24h; centrifuge and wash until the pH of the supernatant is 5-6 to obtain multilayer Ti3C2Tx precipitate; add 50mL of saturated urea aqueous solution per gram of precipitate, stir at 40-50℃ for 12h, sonicate at 400W power for 1h in an ice bath, then centrifuge at 8000rpm for 20min, collect the upper black-green colloidal dispersion Urea-MXene and determine its solid content;
[0058] (2) In-situ modification: Take a Urea-MXene dispersion containing 0.1g MXene solid, add 1.2mL of 0.1M zinc salt aqueous solution dropwise under mechanical stirring, and stir at room temperature for 2 hours to adsorb; slowly add dilute ammonia water to adjust the pH to 8.5-9.0, continue stirring for 1 hour, centrifuge, and wash the precipitate 2-3 times with deionized water to remove free ions and urea;
[0059] (3) Post-treatment: The washed precipitate was vacuum dried at 60-80℃, and then gently ground to obtain urea-intercalated zinc-modified MXene hybrid conductive filler Urea-Zn-MXene. The particle size of the conductive filler Urea-Zn-MXene was 1-5μm.
[0060] The zinc salt is zinc sulfate.
[0061] The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:1.
[0062] The lignin sulfonate is calcium lignin sulfonate; the polyoxyethylene ether surfactant is fatty alcohol polyoxyethylene ether.
[0063] The vulcanizing agent is sulfur and zinc oxide in a mass ratio of 1:3; the stabilizer is a mixture of potassium hydroxide and casein in a mass ratio of 1:1.
[0064] The accelerator is 2-mercaptobenzothiazole, the antioxidant is 2,6-di-tert-butyl-p-cresol, and the thickener is sodium carboxymethyl cellulose.
[0065] A method for preparing a conductive latex, comprising the following steps:
[0066] a. Preparation of conductive filler slurry: 4 parts of the urea intercalated-zinc modified MXenes hybrid conductive filler were mixed with 2 parts of composite dispersant and 30 parts of deionized water, and subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate was 12000 rpm, the ultrasonic power was 300 W, and the treatment time was 40 minutes.
[0067] b. Pretreatment of latex matrix: Mix 100 parts of natural latex and 1.5 parts of stabilizer (based on dry glue) at 30-50℃ for 2 hours for curing treatment;
[0068] c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 1 part vulcanizing agent, 1 part accelerator, and 1 part antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; the chloroform value is controlled at 40-50.
[0069] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 2 parts of thickener to adjust the viscosity, and obtain the conductive latex.
[0070] Example 3
[0071] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 5 parts of conductive filler, 2 parts of composite dispersant, 1.5 parts of vulcanizing agent, 1 part of stabilizer, 1.2 parts of accelerator, 1 part of antioxidant, and 2 parts of thickener.
[0072] The solid content of the natural latex is 50-65%.
[0073] The conductive filler is a urea-intercalated zinc-modified MXene hybrid conductive filler, Urea-Zn-MXene, prepared by the following method:
[0074] (1) Urea-assisted etching-intercalation stripping: Weigh 1g Ti3AlC2 powder and 1g LiF, add 20mL of 9M HCl and react at 33-35℃ for 24h; centrifuge and wash until the pH of the supernatant is 5-6 to obtain multilayer Ti3C2Tx precipitate; add 50mL of saturated urea aqueous solution per gram of precipitate, stir at 40-50℃ for 12h, sonicate at 500W power for 1h in an ice bath, then centrifuge at 8000rpm for 20min, collect the upper black-green colloidal dispersion Urea-MXene and determine its solid content;
[0075] (2) In-situ modification: Take a Urea-MXene dispersion containing 0.1g MXene solid, add 1.6mL of 0.1M zinc salt aqueous solution dropwise under mechanical stirring, and stir at room temperature for 2 hours to adsorb; slowly add dilute ammonia water to adjust the pH to 8.5-9.0, continue stirring for 1 hour, centrifuge, and wash the precipitate 2-3 times with deionized water to remove free ions and urea;
[0076] (3) Post-treatment: The washed precipitate was vacuum dried at 60-80℃, and then gently ground to obtain urea-intercalated zinc-modified MXene hybrid conductive filler Urea-Zn-MXene. The particle size of the conductive filler Urea-Zn-MXene was 1-5μm.
[0077] The zinc salt is zinc chloride.
[0078] The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:1.
[0079] The lignin sulfonate is sodium lignin sulfonate; the polyoxyethylene ether surfactant is alkylphenol polyoxyethylene ether.
[0080] The vulcanizing agent is sulfur and zinc oxide in a mass ratio of 1:2; the stabilizer is a mixture of potassium hydroxide and casein in a mass ratio of 1:1.5.
[0081] The accelerator is tetramethylthiuram disulfide, the antioxidant is N-phenyl-β-naphthylamine, and the thickener is sodium carboxymethyl cellulose.
[0082] A method for preparing a conductive latex, comprising the following steps:
[0083] a. Preparation of conductive filler slurry: 5 parts of the urea intercalated-zinc modified MXenes hybrid conductive filler were mixed with 2 parts of composite dispersant and 30 parts of deionized water, and subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate was 12000 rpm, the ultrasonic power was 400 W, and the treatment time was 60 minutes.
[0084] b. Pretreatment of latex matrix: Mix 100 parts of natural latex and 1 part of stabilizer at 30-50℃ for 2 hours for curing treatment;
[0085] c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 1.5 parts vulcanizing agent, 1.2 parts accelerator, and 1 part antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; the chloroform value is controlled at 40-50.
[0086] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 2 parts of thickener to adjust the viscosity, and obtain the conductive latex.
[0087] Example 4
[0088] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 6 parts of conductive filler, 3 parts of composite dispersant, 1 part of vulcanizing agent, 1 part of stabilizer, 1.1 parts of accelerator, 1.1 parts of antioxidant, and 4 parts of thickener.
[0089] The solid content of the natural latex is 50-65%.
[0090] The conductive filler is a urea-intercalated zinc-modified MXene hybrid conductive filler, Urea-Zn-MXene, prepared by the following method:
[0091] (1) Urea-assisted etching-intercalation stripping: Weigh 1g Ti3AlC2 powder and 1g LiF, add 20mL of 9M HCl and react at 33-35℃ for 24h; centrifuge and wash until the pH of the supernatant is 5-6 to obtain multilayer Ti3C2Tx precipitate; add 50mL of saturated urea aqueous solution per gram of precipitate, stir at 40-50℃ for 12h, sonicate at 500W power for 2h in an ice bath, then centrifuge at 8000rpm for 20min, collect the upper black-green colloidal dispersion Urea-MXene and determine its solid content;
[0092] (2) In-situ modification: Take a Urea-MXene dispersion containing 0.1g MXene solid, add 1.5mL of 0.1M zinc salt aqueous solution dropwise under mechanical stirring, and stir at room temperature for 2 hours to adsorb; slowly add dilute ammonia water to adjust the pH to 8.5-9.0, continue stirring for 1 hour, centrifuge, and wash the precipitate 2-3 times with deionized water to remove free ions and urea;
[0093] (3) Post-treatment: The washed precipitate was vacuum dried at 60-80℃, and then gently ground to obtain urea-intercalated zinc-modified MXene hybrid conductive filler Urea-Zn-MXene. The particle size of the conductive filler Urea-Zn-MXene was 1-5μm.
[0094] The zinc salt is zinc chloride.
[0095] The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:1.
[0096] The lignin sulfonate is calcium lignin sulfonate; the polyoxyethylene ether surfactant is alkylphenol polyoxyethylene ether.
[0097] The vulcanizing agent is sulfur and zinc oxide in a mass ratio of 1:4; the stabilizer is a mixture of potassium hydroxide and casein in a mass ratio of 1:2.
[0098] The accelerator is 2-mercaptobenzothiazole, the antioxidant is N-phenyl-β-naphthylamine, and the thickener is sodium carboxymethyl cellulose.
[0099] A method for preparing a conductive latex, comprising the following steps:
[0100] a. Preparation of conductive filler slurry: 6 parts of the urea intercalated-zinc modified MXenes hybrid conductive filler were mixed with 3 parts of composite dispersant and 40 parts of deionized water, and subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate was 12000 rpm, the ultrasonic power was 400 W, and the treatment time was 30-60 minutes.
[0101] b. Pretreatment of latex matrix: Mix 100 parts of natural latex and 1 part of stabilizer at 30-50℃ for 2 hours for curing treatment;
[0102] c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 1 part vulcanizing agent, 1.1 parts accelerator, and 1.1 parts antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; the chloroform value is controlled at 40-50.
[0103] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 4 parts of thickener to adjust the viscosity, and obtain the conductive latex.
[0104] Example 5
[0105] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 8 parts of conductive filler, 3 parts of composite dispersant, 2 parts of vulcanizing agent, 2 parts of stabilizer, 1.5 parts of accelerator, 1.5 parts of antioxidant, and 1 part of thickener.
[0106] The solid content of the natural latex is 50-65%.
[0107] The conductive filler is a urea-intercalated zinc-modified MXene hybrid conductive filler, Urea-Zn-MXene, prepared by the following method:
[0108] (1) Urea-assisted etching-intercalation stripping: Weigh 1g Ti3AlC2 powder and 1g LiF, add 20mL of 9M HCl and react at 33-35℃ for 24h; centrifuge and wash until the pH of the supernatant is 5-6 to obtain multilayer Ti3C2Tx precipitate; add 50mL of saturated urea aqueous solution per gram of precipitate, stir at 40-50℃ for 12h, sonicate at 300-500W power for 1-2h in an ice bath, then centrifuge at 8000rpm for 20min, collect the upper black-green colloidal dispersion Urea-MXene and determine its solid content;
[0109] (2) In-situ modification: Take a Urea-MXene dispersion containing 0.1g MXene solid, add 1.2-1.8mL of 0.1M zinc salt aqueous solution dropwise under mechanical stirring, and stir at room temperature for 2 hours to adsorb; slowly add dilute ammonia water to adjust the pH to 8.5-9.0, continue stirring for 1 hour, centrifuge, and wash the precipitate 2-3 times with deionized water to remove free ions and urea;
[0110] (3) Post-treatment: The washed precipitate was vacuum dried at 60-80℃, and then gently ground to obtain urea-intercalated zinc-modified MXene hybrid conductive filler Urea-Zn-MXene. The particle size of the conductive filler Urea-Zn-MXene was 1-5μm.
[0111] The zinc salt is one of zinc acetate, zinc sulfate, or zinc chloride.
[0112] The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:1.
[0113] The lignin sulfonate is calcium lignin sulfonate; the polyoxyethylene ether surfactant is fatty alcohol polyoxyethylene ether.
[0114] The vulcanizing agent is sulfur and zinc oxide in a mass ratio of 1:4; the stabilizer is a mixture of potassium hydroxide and casein in a mass ratio of 1:2.
[0115] The accelerator is tetramethylthiuram disulfide, the antioxidant is N-phenyl-β-naphthylamine, and the thickener is sodium carboxymethyl cellulose.
[0116] A method for preparing a conductive latex, comprising the following steps:
[0117] a. Preparation of conductive filler slurry: 8 parts of the urea intercalated-zinc modified MXenes hybrid conductive filler were mixed with 3 parts of composite dispersant and 40 parts of deionized water, and subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate was 12000 rpm, the ultrasonic power was 400 W, and the treatment time was 60 minutes.
[0118] b. Pretreatment of latex matrix: Mix 100 parts of natural latex and 2 parts of stabilizer at 30-50℃ for 2 hours for curing treatment;
[0119] c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 2 parts vulcanizing agent, 1.5 parts accelerator, and 1.5 parts antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; the chloroform value is controlled at 40-50.
[0120] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 1 part thickener to adjust the viscosity, and obtain the conductive latex.
[0121] Comparative Example 1
[0122] In this comparative example, except that the conductive filler used is commercially available MXene, all other raw materials and process steps are the same as in Example 1, namely:
[0123] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3 parts of conductive filler, 1 part of composite dispersant, 0.5 parts of vulcanizing agent, 0.5 parts of stabilizer, 0.5 parts of accelerator, 0.5 parts of antioxidant, and 5 parts of thickener.
[0124] The solid content of the natural latex is 50-65%.
[0125] The conductive filler is selected from MXenes material with a particle size of 1-5 μm, which was purchased from Shanghai Xiangtian Nanomaterials Co., Ltd.
[0126] A method for preparing a conductive latex, comprising the following steps:
[0127] a. Preparation of conductive filler slurry: 3 parts of MXenes conductive filler, 1 part of composite dispersant, and 20 parts of deionized water were mixed and subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate was 8000 rpm, the ultrasonic power was 200 W, and the treatment time was 30 minutes.
[0128] b. Pretreatment of latex matrix: Mix 100 parts of natural latex (dry weight) and 0.5 parts of stabilizer at 30-50℃ for 1 hour for curing treatment;
[0129] c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 0.5 parts of vulcanizing agent, 0.5 parts of accelerator, and 0.5 parts of antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; the chloroform value is controlled at 40-50.
[0130] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 5 parts of thickener to adjust the viscosity, and obtain the conductive latex.
[0131] Comparative Example 2
[0132] In this comparative example, except that commercially available ordinary carbon black was used instead of urea-intercalated zinc-modified MXene hybrid conductive filler Urea-Zn-MXene for the use of conductive filler, all other raw materials and process steps were the same as in Example 1, namely:
[0133] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3 parts of conductive filler, 1 part of composite dispersant, 0.5 parts of vulcanizing agent, 0.5 parts of stabilizer, 0.5 parts of accelerator, 0.5 parts of antioxidant, and 5 parts of thickener.
[0134] The solid content of the natural latex is 50-65%.
[0135] The conductive filler is carbon black, with a particle size of 1-5 μm, purchased from Tianjin Huayuan Chemical Technology Co., Ltd.
[0136] A method for preparing a conductive latex, comprising the following steps:
[0137] a. Preparation of conductive filler slurry: 3 parts carbon black, 1 part composite dispersant, and 20 parts deionized water are mixed and subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; the high-speed shearing rate is 8000 rpm, the ultrasonic power is 200 W, and the treatment time is 30 minutes.
[0138] b. Pretreatment of latex matrix: Mix 100 parts of natural latex (dry weight) and 0.5 parts of stabilizer at 30-50℃ for 1 hour for curing treatment;
[0139] c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 0.5 parts of vulcanizing agent, 0.5 parts of accelerator, and 0.5 parts of antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; the chloroform value is controlled at 40-50.
[0140] d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 5 parts of thickener to adjust the viscosity, and obtain the conductive latex.
[0141] Comparative Example 3
[0142] In this comparative example, except that the composite dispersant uses only lignin sulfonate, the other raw materials and process steps are the same as in Example 1, that is:
[0143] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3 parts of conductive filler, 1 part of dispersant, 0.5 parts of vulcanizing agent, 0.5 parts of stabilizer, 0.5 parts of accelerator, 0.5 parts of antioxidant, and 5 parts of thickener.
[0144] The dispersant is lignin sulfonate.
[0145] The lignin sulfonate is sodium lignin sulfonate.
[0146] Comparative Example 4
[0147] In this comparative example, except that the composite dispersant uses only polyoxyethylene ether surfactants, the other raw materials and process steps are the same as in Example 1, that is:
[0148] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3 parts of conductive filler, 1 part of dispersant, 0.5 parts of vulcanizing agent, 0.5 parts of stabilizer, 0.5 parts of accelerator, 0.5 parts of antioxidant, and 5 parts of thickener.
[0149] The dispersant is a polyoxyethylene ether surfactant.
[0150] The polyoxyethylene ether surfactant is an alkylphenol polyoxyethylene ether.
[0151] Comparative Example 5
[0152] In this comparative example, except for the change in the ratio of lignin sulfonate to polyoxyethylene ether surfactant in the composite dispersant, all other raw materials and process steps are the same as in Example 1, namely:
[0153] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3 parts of conductive filler, 1 part of composite dispersant, 0.5 parts of vulcanizing agent, 0.5 parts of stabilizer, 0.5 parts of accelerator, 0.5 parts of antioxidant, and 5 parts of thickener.
[0154] The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 2:1.
[0155] The lignin sulfonate is sodium lignin sulfonate; the polyoxyethylene ether surfactant is alkylphenol polyoxyethylene ether.
[0156] Comparative Example 6
[0157] In this comparative example, except for the change in the ratio of lignin sulfonate to polyoxyethylene ether surfactant in the composite dispersant, all other raw materials and process steps are the same as in Example 1, namely:
[0158] A conductive latex comprises the following raw materials in parts by weight: 100 parts of natural latex (dry weight), 3 parts of conductive filler, 1 part of composite dispersant, 0.5 parts of vulcanizing agent, 0.5 parts of stabilizer, 0.5 parts of accelerator, 0.5 parts of antioxidant, and 5 parts of thickener.
[0159] The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:2.
[0160] The lignin sulfonate is sodium lignin sulfonate; the polyoxyethylene ether surfactant is alkylphenol polyoxyethylene ether.
[0161] Performance testing
[0162] Gloves were prepared using latex in the examples and comparative cases. The glove blank was coated with the conductive latex by immersing it in the latex, followed by drying and vulcanization molding processes to ensure a firm adhesion of the conductive latex layer to the glove blank surface. The coating thickness was controlled between 0.1 and 0.3 mm. Five samples were repeated for each experiment, and the average result was taken.
[0163] The glove blank was made of 15-needle nylon and spandex gloves. Testing was conducted according to the method in EU standard EN388 (corresponding to Chinese standard GB24541-2009). Surface resistivity: The surface resistivity was measured using a resistivity meter at a test voltage of 100V. Chemical resistance test: The chemical resistance of the film samples was tested according to EN ISO 374-1 and EN 16523-1. The circular samples were left to stand at (23±1)℃ for 3 hours and then used to separate distilled water from chemicals. The pH value on the distilled water side was monitored in real time using a pH meter. When the chemical penetration rate reached 1.0 µg·cm⁻¹... -2 ·min-1 Record the penetration time. Comfort: Based on the user's experience, if the glove fits the hand well, allows for flexible operation, and there is no pressure on the fingers, then the comfort level is excellent; if the rubber surface is hard, making it difficult to bend the fingers or hindering operation, then the comfort level is poor. If the rubber surface is slightly hard but still flexible, allowing for generally flexible operation, then the comfort level is good.
[0164] The test results are shown in Table 1:
[0165] Table 1 Performance Test Results
[0166]
[0167] The data in the table show that the conductive latex in the example exhibits the best performance in all performance tests, demonstrating excellent conductivity. Simultaneously, its abrasion resistance, puncture resistance, and resistance to chemical penetration time are all superior, indicating that this formulation has significant advantages in enhancing mechanical and protective properties. This demonstrates that the two-dimensional structure of the urea-intercalated zinc-modified MXenes hybrid conductive filler not only significantly improves the material's conductive network construction ability but also enhances the intermatrix bonding force through interfacial synergy. Furthermore, a reasonable ratio of composite dispersant can effectively improve the dispersion stability of the filler in the latex, preventing agglomeration and further improving the overall performance of the composite material.
[0168] In contrast, Comparative Examples 1 to 6 exhibited varying degrees of performance degradation due to adjustments in key raw materials or process parameters. For instance, Comparative Example 1, using ordinary MXene as the conductive filler, still retained some conductivity, but its surface resistivity increased by two orders of magnitude compared to Example 5, and its abrasion resistance and puncture resistance were significantly reduced. In Comparative Example 2, replacing the special conductive filler with carbon black further deteriorated the conductivity, with the surface resistivity even exceeding 10⁻⁶. 7 Ω, while other performance indicators such as penetration time and comfort are also significantly deteriorated, failing to meet the requirements of high-standard work gloves.
[0169] As can be seen from Comparative Examples 3 to 6, the composition and ratio of the composite dispersant have a significant impact on the overall performance of the gloves. Using only a single component (lignin sulfonate or polyoxyethylene ether surfactant) leads to insufficient dispersion, thereby affecting the uniform distribution of conductive fillers in the latex matrix, ultimately reflected in higher surface resistivity and a decrease in other performance indicators. Changing the mass ratio of lignin sulfonate to polyoxyethylene ether surfactant also weakens the synergistic effect of the dispersion system, making it difficult for the overall performance to reach the level of the examples.
[0170] In summary, by optimizing the type of conductive filler, the ratio of composite dispersant, and the preparation process, this invention has successfully developed a conductive latex that combines excellent conductivity, mechanical properties, and comfort, making it suitable for the production needs of high-performance work gloves.
[0171] It should be noted that the above embodiments are merely some preferred embodiments of the present invention, and not all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.
Claims
1. A conductive latex, characterized in that, The raw materials include the following parts by weight: 100 parts natural latex (dry weight), 3-8 parts conductive filler, 1-3 parts composite dispersant, 0.5-2 parts vulcanizing agent, 0.5-2 parts stabilizer, 0.5-1.5 parts accelerator, 0.5-1.5 parts antioxidant, and 1-5 parts thickener; The conductive filler is a urea-intercalated zinc-modified MXene hybrid conductive filler, Urea-Zn-MXene, prepared by the following method: (1) Urea-assisted etching-intercalation stripping: Weigh 1g Ti3AlC2 powder and 1g LiF, add 20mL of 9M HCl and react at 33-35℃ for 24h; centrifuge and wash until the pH of the supernatant is 5-6 to obtain multilayer Ti3C2Tx precipitate; add 50mL of saturated urea aqueous solution per gram of precipitate, stir at 40-50℃ for 12h, sonicate at 300-500W power for 1-2h in an ice bath, then centrifuge at 8000rpm for 20min, collect the upper black-green colloidal dispersion Urea-MXene and determine its solid content; (2) In-situ modification: Take Urea-MXene dispersion containing 0.1g MXenes solid, add 1.2-1.8mL of 0.1M zinc salt aqueous solution dropwise under mechanical stirring, stir and adsorb at room temperature for 2 hours; slowly add dilute ammonia water to adjust pH to 8.5-9.0, continue stirring for 1 hour, centrifuge, and wash the precipitate 2-3 times with deionized water; (3) Post-treatment: The washed precipitate was vacuum dried at 60-80℃, and then gently ground to obtain urea-Zn-MXene hybrid conductive filler. The composite dispersant is a composite dispersant prepared by compounding lignin sulfonate and polyoxyethylene ether surfactant in a mass ratio of 1:
1. The lignin sulfonate is sodium lignin sulfonate or calcium lignin sulfonate; the polyoxyethylene ether surfactant is alkylphenol polyoxyethylene ether or fatty alcohol polyoxyethylene ether.
2. The conductive latex according to claim 1, wherein The solid content of the natural latex is 50-65%.
3. The conductive latex of claim 1, wherein The zinc salt is one of zinc acetate, zinc sulfate, or zinc chloride.
4. The conductive latex of claim 1, wherein The vulcanizing agent is sulfur and zinc oxide in a mass ratio of 1:(2-4); the stabilizer is a mixture of potassium hydroxide and casein in a mass ratio of 1:(0.5-2).
5. The conductive latex of claim 1, wherein The accelerator is at least one of tetramethylthiuram disulfide or 2-mercaptobenzothiazole, the antioxidant is one of N-phenyl-β-naphthylamine or 2,6-di-tert-butyl-p-cresol, and the thickener is sodium carboxymethyl cellulose.
6. A process for the preparation of the electrically conductive latex according to any one of claims 1 to 5, characterized in that, Includes the following steps: a. Preparation of conductive filler slurry: 3-8 parts of the urea intercalated-zinc modified MXenes hybrid conductive filler are mixed with 1-3 parts of composite dispersant and 20-40 parts of deionized water, and then subjected to high-speed shearing and ultrasonic treatment to prepare a stable and uniform conductive filler slurry; b. Pretreatment of latex matrix: Mix 100 parts of natural latex (dry weight) and 0.5-2 parts of stabilizer at 30-50℃ for 1-2 hours for curing treatment; c. Composite and vulcanization: Slowly add the conductive filler slurry prepared in step a to the latex matrix after pretreatment in step b, and stir evenly; then add 0.5-2 parts of vulcanizing agent, 0.5-1.5 parts of accelerator, and 0.5-1.5 parts of antioxidant, and carry out pre-vulcanization reaction at 40-50℃ until the required chloroform value is reached; d. Viscosity adjustment and finished product: Cool the pre-vulcanized latex obtained in step c to room temperature, add 1-5 parts of thickener to adjust the viscosity, and obtain the conductive latex.
7. An electrically conductive latex glove characterized in that, The conductive latex glove comprises a conductive latex as described in any one of claims 1 to 5 and a glove blank; the conductive latex layer is firmly attached to the surface of the glove blank by immersing the glove blank in the conductive latex for coating, and by a drying and vulcanization molding process.