A micro-ammonia emulsion medical examination glove and a preparation method thereof

Abstract

The application belongs to the technical field of medical latex gloves, and particularly relates to a micro-ammonia latex medical examination glove and a preparation method thereof. The micro-ammonia latex medical examination glove comprises modified deproteinized natural concentrated latex 100 parts, sulfur 1-2.5 parts, zinc oxide 0.5-1.5 parts, an accelerator 0.5-1.5 parts, an antioxidant 1-2 parts and a surfactant 0.1-0.5 parts. The preparation of the modified deproteinized natural concentrated latex comprises the following steps: filtering and removing impurities from fresh natural latex, supplementing ammonia to 0.05-0.1%, and then adding a stabilizer, porous rod-like silicon dioxide and alkaline protease to perform enzymatic reaction; centrifuging to obtain micro-ammonia deproteinized concentrated natural latex and porous rod-like silicon dioxide, washing the porous rod-like silicon dioxide, and mixing the washed porous rod-like silicon dioxide with the micro-ammonia deproteinized concentrated natural latex to obtain the micro-ammonia deproteinized concentrated natural latex. The application improves the removal rate of proteins through the shearing and friction of the porous rod-like silicon dioxide, and further uses the porous rod-like silicon dioxide as a reinforcing agent to improve the mechanical properties of the glove.

Description

Technical Field

[0001] This invention belongs to the field of medical latex glove technology, specifically relating to a micro-ammonia latex medical examination glove and its preparation method. Background Technology

[0002] Medical latex gloves, as indispensable protective equipment in the medical field, are widely used in surgical, nursing, and laboratory procedures. Their main function is to establish a physical barrier to prevent cross-infection between medical staff and patients, while protecting medical staff from chemicals and pathogens. Currently, medical latex gloves are mostly made from natural rubber latex as the main raw material, manufactured through processes such as impregnation molding and vulcanization cross-linking. They possess excellent elasticity, flexibility, fit, and biocompatibility, and have long held a dominant position in the field of medical protection.

[0003] However, existing natural rubber-based medical latex gloves still have two major problems in practical applications, which seriously restrict their safety and reliability: First, there is a higher risk of allergic reactions. Natural rubber latex contains various proteins, lipids, and residual chemicals (such as vulcanization accelerators and antioxidants), which may trigger abnormal reactions in the human immune system. Clinical studies have shown that healthcare workers, as long-term, high-frequency users, have a significantly higher probability of developing allergies after contact with natural latex gloves than the general population. These allergies mainly manifest as contact dermatitis (delayed-type hypersensitivity reaction), urticaria, and even anaphylactic shock (immediate-type hypersensitivity reaction). Although current technologies reduce protein content through methods such as latex centrifugation purification and enzymatic hydrolysis, it is still difficult to effectively eliminate the risk of allergies, especially for highly sensitive individuals where the protective effect remains unsatisfactory.

[0004] Secondly, the mechanical strength is not adequately matched with the usage requirements. Medical latex gloves must simultaneously meet mechanical performance requirements such as tensile strength, tear strength, and abrasion resistance to cope with complex medical operation scenarios (such as holding surgical instruments and repetitive flexion and extension movements). The strength of existing natural latex gloves mainly relies on the vulcanized cross-linked network of rubber molecular chains, but its cross-linking density distribution is uneven, and during processing, fluctuations in film thickness and differences in vulcanization degree can easily lead to localized weakness in strength. In actual use, gloves often fail prematurely due to tears at the fingertips, finger gaps, etc., which not only increases medical costs but may also lead to exposure risks for medical staff and patients due to protective damage. In addition, in pursuit of good fit and comfort, existing gloves are often designed to be relatively thin (usually 0.08~0.15mm thick), further exacerbating the problem of insufficient strength; while simply increasing the thickness can improve strength, it leads to a decrease in flexibility and affects the accuracy of delicate operations.

[0005] Therefore, developing a medical latex glove that can reduce the risk of allergies while significantly improving mechanical strength while maintaining excellent elasticity and comfort has become an urgent technical problem to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a micro-ammonia latex medical examination glove and its preparation method. By adding porous rod-shaped silica during the enzymatic hydrolysis process, the shearing effect of silica on rubber hydrocarbon particles during stirring is utilized to improve the protein dissociation efficiency, thereby helping to improve the protein removal rate. At the same time, the recovered porous rod-shaped silica can be reused as a reinforcing filler for the latex glove to improve its strength. This achieves two benefits at once and fully utilizes the raw material, making it highly practical for industrial applications.

[0007] To achieve the above objectives, the present invention provides a micro-ammonia latex medical examination glove, the raw materials of which include: 100 parts of modified deproteinized natural concentrated latex, 1-2.5 parts of sulfur, 0.5-1.5 parts of zinc oxide, 0.5-1.5 parts of accelerator, 1-2 parts of antioxidant, and 0.1-0.5 parts of surfactant; The method for preparing the modified deproteinized natural concentrated latex includes: S1, Fresh natural latex is filtered to remove impurities and clumps, ammonia is added to bring the mass fraction to 0.05~0.1%, and then a stabilizer is added to obtain the first latex solution; S2, add porous rod-shaped silica and alkaline protease to the first latex solution, and carry out enzymatic hydrolysis while stirring. The shearing and friction of the porous rod-shaped silica will improve the protein removal rate, and a second latex solution will be obtained. S3, the second latex solution is centrifuged to obtain the upper layer of micro-ammonia-deproteinized concentrated natural latex and the lower layer of porous rod-shaped silica. The porous rod-shaped silica is washed with water and then mixed with the micro-ammonia-deproteinized concentrated natural latex to obtain the micro-ammonia-deproteinized concentrated natural latex.

[0008] Furthermore, in step S2, the alkaline protease is first dissolved in water, and then the porous rod-shaped silica is added to it for impregnation and adsorption. Then, the mixed solution is added to the first latex solution.

[0009] Furthermore, the porous rod-shaped silica has a length of 0.3-1µm and a diameter of 50-100nm; the amount of silica particles added is 5%-10% of the mass of the first latex solution.

[0010] Furthermore, the method for preparing the porous rod-shaped silica includes: S21. Add tetraethyl orthosilicate to a mixed solution of water and ethanol containing hexadecyltrimethylammonium bromide, and then add hydrochloric acid to control the pH value to 2-4 to obtain silica sol. S22. Place the AAO template in the silica sol and perform hydrolysis and condensation; then remove the template and heat it to 120-160℃ for 0.5-3h; the AAO template has a pore size of 50-200nm and a pore depth of 0.5-2µm. S23. The AAO template is removed by dissolution, followed by centrifugation, washing, and drying. Then, the hexadecyltrimethylammonium bromide is removed by calcination at 500-600℃ to obtain porous rod-shaped silica.

[0011] Furthermore, in step S23, a vinyl silane coupling agent is used to hydrolyze and condense with porous rod-shaped silica to obtain vinyl silane coupling agent modified porous rod-shaped silica, and then isoprene and vinyl silane coupling agent are used for free radical polymerization to obtain modified porous rod-shaped silica.

[0012] Furthermore, in step S21, the volume ratio of water to ethanol is 1:(3-5); the amount of hexadecyltrimethylammonium bromide added is 10%-15% of tetraethyl orthosilicate; In step S22, the hydrolysis condensation temperature is 35-60℃; In step S23, the AAO template is removed by soaking in a 5wt% phosphoric acid solution.

[0013] Furthermore, the first latex solution has a solid content of 30%-40%, and the amount of alkaline protease added is 0.01%-0.5% of the mass of the first latex solution; the micro-ammonia-deproteinized concentrated natural latex has a solid content of 60%-70%. The enzymatic hydrolysis reaction is carried out at a temperature of 30-45℃ for 3-8 hours.

[0014] Furthermore, the stabilizer is sodium dodecyl sulfate, and the amount added is 1%-3% of the mass of the fresh natural latex.

[0015] The present invention also provides a method for preparing the microammonia latex medical examination gloves described in any one of the above claims, comprising: adding 1-2.5 parts of sulfur, 0.5-1.5 parts of zinc oxide, 0.5-1.5 parts of accelerator, 1-2 parts of antioxidant and 0.1-0.5 parts of surfactant to 100 parts of modified deproteinized natural concentrated latex, mixing evenly, pouring into a mold, drying, and vulcanizing to obtain the microammonia latex medical examination gloves.

[0016] Furthermore, the vulcanization temperature is 90–110°C, and the time is 15–30 min.

[0017] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages: 1. The micro-ammonia latex medical examination gloves provided by this invention, by adding porous rod-shaped silica during the enzymatic hydrolysis process, utilizes the shearing effect of silica on rubber hydrocarbon particles during stirring to improve the protein dissociation efficiency. At the same time, its porous structure adsorbs water, which can change the local osmotic pressure of the latex, thereby causing the rubber hydrocarbon particles to expand and stretch the protein adsorption layer, thus helping to improve the protein removal rate. In addition, the recovered porous rod-shaped silica can be reused as a reinforcing filler for the latex gloves to improve their strength. This achieves two benefits at once and makes full use of raw materials, making it highly practical for industrial applications.

[0018] 2. Grafting modification of porous rod-shaped silica with vinyl silane coupling agent and isoprene can increase the compatibility between porous rod-shaped silica and rubber hydrocarbon particles, and improve mechanical strength through chemical bonding and molecular entanglement. Attached Figure Description

[0019] Figure 1 Flowchart of the preparation method for modified deproteinized natural concentrated latex. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0021] This invention provides a micro-ammonia latex medical examination glove, the raw materials of which include: 100 parts of modified deproteinized natural concentrated latex, 1-2.5 parts of sulfur, 0.5-1.5 parts of zinc oxide, 0.5-1.5 parts of accelerator, 1-2 parts of antioxidant and 0.1-0.5 parts of surfactant.

[0022] Among them, such as Figure 1 As shown, the preparation method of the modified deproteinized natural concentrated latex includes: S1, Fresh natural latex is filtered to remove impurities and clumps, ammonia is added to bring the mass fraction to 0.05~0.1%, and then a stabilizer is added to obtain the first latex solution; S2, add porous rod-shaped silica and alkaline protease to the first latex solution, and carry out the enzymatic hydrolysis reaction while stirring (stirring speed is 200-300 r / min); the shearing and friction of porous rod-shaped silica is used to improve the protein removal rate to obtain the second latex solution. S3, the second latex solution is centrifuged to obtain the upper layer of micro-ammonia-deproteinized concentrated natural latex and the lower layer of porous rod-shaped silica. The porous rod-shaped silica is washed with water and then mixed with the micro-ammonia-deproteinized concentrated natural latex to obtain the micro-ammonia-deproteinized concentrated natural latex.

[0023] This process utilizes the tips of the rod-shaped silica to enhance the shearing effect on the rubber hydrocarbon particles, disrupting the surface protein adsorption layer. Simultaneously, its porous structure adsorbs moisture, altering the local osmotic pressure of the latex. This causes the rubber hydrocarbon particles to expand, stretching the protein adsorption layer and promoting the detachment of loosely bound proteins, thus increasing the protein removal rate. After enzymatic hydrolysis for protein removal, the separated porous rod-shaped silica is washed with water to remove any adsorbed proteins or their enzymatic hydrolysis products. It is then added to the latex solution as a reinforcing filler. The one-dimensional structure of the rod-shaped filler can more efficiently transfer stress and hinder crack propagation, while its porous structure facilitates the embedding of rubber molecules, enhancing the anchoring effect and thus improving strength.

[0024] Furthermore, in step S2, the alkaline protease is first dissolved in water, and then the porous rod-shaped silica is added to it for impregnation and adsorption. Next, the mixed solution is added to the first latex solution. This operation allows the alkaline protease to be adsorbed within the pores, which helps to enzymatically hydrolyze the proteins adsorbed into the pores, effectively reducing the protein content in the porous rod-shaped silica after subsequent washing.

[0025] Furthermore, the porous rod-shaped silica has a length of 0.3-1µm and a diameter of 50-100nm; the amount of silica particles added is 5%-10% of the mass of the first latex solution.

[0026] Furthermore, the method for preparing the porous rod-shaped silica includes: S21. Add tetraethyl orthosilicate to a mixed solution of water and ethanol containing hexadecyltrimethylammonium bromide, and then add hydrochloric acid to control the pH value to 2-4 to obtain silica sol. S22. Place the AAO (anodic aluminum oxide) template in the silica sol and perform hydrolysis and condensation; then remove the template and heat it to 120-160℃ for 0.5-3h; the AAO template has a pore size of 50-200nm and a pore depth of 0.5-2µm; S23. The AAO template is removed by dissolution, followed by centrifugation, washing, and drying. Then, the hexadecyltrimethylammonium bromide is removed by calcination at 500-600℃ to obtain porous rod-shaped silica.

[0027] In step S23, a vinyl silane coupling agent is hydrolyzed and condensed with porous rod-shaped silica to obtain vinyl silane coupling agent-modified porous rod-shaped silica. Then, isoprene and the vinyl silane coupling agent are subjected to free radical polymerization to obtain modified porous rod-shaped silica. This process increases the compatibility of porous rod-shaped silica with rubber hydrocarbon particles and improves mechanical strength through chemical bonding and molecular entanglement. The mass ratio of vinyltriethoxysilane, isoprene, and porous rod-shaped silica is 1:(3-6):10.

[0028] In step S21, the volume ratio of water to ethanol is 1:(3-5); the amount of hexadecyltrimethylammonium bromide added is 10%-15% of tetraethyl orthosilicate. In step S22, the hydrolysis condensation temperature is 35-60℃; In step S23, the AAO template is removed by soaking in a 5wt% phosphoric acid solution.

[0029] Furthermore, the solid content of the first latex solution is 30%-40%, the amount of alkaline protease added is 0.01%-0.5% of the mass of the first latex solution; the solid content of the micro-ammonia-deproteinized concentrated natural latex is 60%-70%; the temperature of the enzymatic hydrolysis reaction is 30-45℃, and the time is 3-8h.

[0030] Furthermore, the stabilizer is sodium dodecyl sulfate, and the amount added is 1%-3% of the mass of the fresh natural latex.

[0031] The present invention also provides a method for preparing the microammonia latex medical examination gloves described in any one of the above claims, comprising: adding 1-2.5 parts of sulfur, 0.5-1.5 parts of zinc oxide, 0.5-1.5 parts of accelerator, 1-2 parts of antioxidant and 0.1-0.5 parts of surfactant to 100 parts of modified deproteinized natural concentrated latex, mixing evenly, pouring into a mold, drying, and vulcanizing to obtain the microammonia latex medical examination gloves.

[0032] Furthermore, the vulcanization temperature is 90–110°C, and the time is 15–30 min.

[0033] Example 1 A method for preparing a micro-ammonia latex medical examination glove includes: adding 2 parts sulfur, 1 part zinc oxide, 1 part accelerator, 1.2 parts antioxidant and 0.3 parts surfactant to 100 parts modified deproteinized natural concentrated latex, mixing evenly, pouring into a mold, drying, and vulcanizing (temperature 100℃, time 20min) to obtain a micro-ammonia latex medical examination glove.

[0034] The method for preparing the modified deproteinized natural concentrated latex includes: S1, Fresh natural latex is filtered to remove impurities and lumps, ammonia is added to a mass fraction of 0.06%, and then sodium dodecyl sulfate is added as a stabilizer to obtain a first latex solution (solid content of 33%); the amount of sodium dodecyl sulfate added is 2% of the mass of the fresh natural latex; S2, mix porous rod-shaped silica (7% of the mass of the first latex solution) and alkaline protease (0.1% of the mass of the first latex solution) aqueous solution evenly, then add it to the first latex solution, and carry out enzymatic hydrolysis reaction for 5 hours while stirring (stirring speed is 200 r / min). The shearing and friction effects of porous rod-shaped silica are used to improve the protein removal rate, and a second latex solution is obtained. S3, the second latex solution is centrifuged to obtain the upper layer of micro-ammonia-deproteinized concentrated natural latex and the lower layer of porous rod-shaped silica. The porous rod-shaped silica is washed with water and then mixed with the micro-ammonia-deproteinized concentrated natural latex (solid content 65%) to obtain the micro-ammonia-deproteinized concentrated natural latex.

[0035] The preparation methods for porous rod-shaped silica include: S21. Add tetraethyl orthosilicate to a mixed solution of water and ethanol (volume ratio 1:4) containing hexadecyltrimethylammonium bromide (12% of tetraethyl orthosilicate), and then add hydrochloric acid to control the pH value to 3 to obtain silica sol. S22. Place the AAO (anodic aluminum oxide) template in the silica sol and perform hydrolysis and condensation; then remove the template and heat it to 140°C for 1 hour; the AAO template has a pore size of 80 nm and a pore depth of 0.6 µm. S23. The AAO template is removed by dissolving it in a 5wt% phosphoric acid solution, centrifuged, washed, and dried, and then calcined at 550℃ to remove hexadecyltrimethylammonium bromide, yielding porous rod-shaped silica.

[0036] Example 2 The difference from Example 1 is that in step S23, vinyltriethoxysilane is hydrolyzed and condensed with porous rod-shaped silica to obtain vinylsilane coupling agent-modified porous rod-shaped silica, and then isoprene is subjected to free radical polymerization with vinylsilane coupling agent to obtain modified porous rod-shaped silica. The mass ratio of vinyltriethoxysilane, isoprene, and porous rod-shaped silica is 1:5:10. Everything else is the same as in Example 1 and will not be repeated here.

[0037] Example 3 The difference from Example 2 is that the amount of modified porous rod-shaped silica added is 5% of the mass of the first latex solution. Everything else is the same as in Example 2, and will not be repeated here.

[0038] Comparative Example 1 The difference from Example 2 is that the amount of porous rod-shaped silica added in step S2 is 2% of the mass of the first latex solution.

[0039] Comparative Example 2 The difference from Example 2 is that cetyltrimethylammonium bromide was not added in step S21.

[0040] Comparative Example 3 The difference from Example 2 is that the silicon dioxide particles are 200 nm in length and 80 nm in diameter. Everything else is the same as in Example 2, and will not be repeated here.

[0041] The prepared deproteinized natural rubber latex was sampled according to ISO 123. A casting process was used, employing commercially available polypropylene petri dishes with an inner diameter of 90 mm. The petri dishes were placed horizontally on a horizontal support, and a certain amount of natural rubber latex was poured into the dishes, spreading it evenly across the bottom. The films were then allowed to air dry at room temperature until transparent. The finished film was then peeled off the bottom of the petri dish; the thickness of the dried film was 0.3 ± 0.05 mm. The protein content extracted by water extraction from the air-dried film was determined according to the method described in ASTM D5712.

[0042] The mechanical stability of the deproteinized natural latex was determined according to ISO 35, the method for determining the mechanical stability of concentrated natural rubber latex. Tensile properties were tested according to the testing standard GB / T528-2009.

[0043] Table 1 Performance test results of the examples and comparative examples

[0044] Table 1 shows that when an appropriate amount of porous rod-shaped silica is added to assist enzymatic hydrolysis, the protein content decreases significantly. In contrast, when the amount of silica used in Comparative Example 1 is reduced, the protein content increases, indicating that porous rod-shaped silica helps with protein dissociation and removal. Furthermore, adding an appropriate amount of porous rod-shaped silica also improves strength. When a porous structure is not used, the protein content increases and the tensile strength decreases, indicating that a porous structure also facilitates protein removal and strength improvement. When vinyl silane coupling agent and isoprene are used for modification, the protein content is the lowest and the strength is the highest, indicating that the modified material has better protein adsorption and stronger compatibility and entanglement with rubber.

[0045] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A micro-ammonia latex medical examination glove, characterized in that, Its raw materials include: 100 parts modified deproteinized natural concentrated latex, 1-2.5 parts sulfur, 0.5-1.5 parts zinc oxide, 0.5-1.5 parts accelerator, 1-2 parts antioxidant and 0.1-0.5 parts surfactant; The preparation method of the modified deproteinized natural concentrated latex includes: S1, Fresh natural latex is filtered to remove impurities and clumps, ammonia is added to bring the mass fraction to 0.05~0.1%, and then a stabilizer is added to obtain the first latex solution; S2, porous rod-shaped silica and alkaline protease are added to the first latex solution, and the enzymatic hydrolysis reaction is carried out while stirring. The shearing and friction effects of the porous rod-shaped silica improve the protein removal rate, resulting in a second latex solution. The porous rod-shaped silica has a length of 0.3-1µm and a diameter of 50-100nm. The amount of porous rod-shaped silica added is 5%-10% of the mass of the first latex solution. S3, the second latex solution is centrifuged to obtain an upper layer of micro-ammonia-deproteinized concentrated natural latex and a lower layer of porous rod-shaped silica. The porous rod-shaped silica is washed with water and then mixed with the micro-ammonia-deproteinized concentrated natural latex to obtain the modified deproteinized natural concentrated latex.

2. The microammonia latex medical examination glove according to claim 1, characterized in that, In step S2, alkaline protease is first dissolved in water, and then the porous rod-shaped silica is added to it for impregnation and adsorption. Then the mixed solution is added to the first latex solution.

3. The microammonia latex medical examination glove according to claim 1, characterized in that, The method for preparing the porous rod-shaped silica includes: S21. Add tetraethyl orthosilicate to a mixed solution of water and ethanol containing hexadecyltrimethylammonium bromide, and then add hydrochloric acid to control the pH value to 2-4 to obtain silica sol. S22. Place the AAO template in the silica sol and perform hydrolysis and condensation; then remove the template and heat it to 120-160℃ for 0.5-3h; the AAO template has a pore size of 50-200nm and a pore depth of 0.5-2µm. S23. The AAO template is removed by dissolution, followed by centrifugation, washing, and drying. Then, the hexadecyltrimethylammonium bromide is removed by calcination at 500-600℃ to obtain porous rod-shaped silica.

4. The microammonia latex medical examination glove according to claim 3, characterized in that, In step S23, a vinyl silane coupling agent is used to hydrolyze and condense with porous rod-shaped silica to obtain vinyl silane coupling agent modified porous rod-shaped silica. Then, isoprene and vinyl silane coupling agent are used for free radical polymerization to obtain modified porous rod-shaped silica.

5. The microammonia latex medical examination glove according to claim 3, characterized in that, In step S21, the volume ratio of water to ethanol is 1:(3-5); the amount of hexadecyltrimethylammonium bromide added is 10%-15% of tetraethyl orthosilicate. In step S22, the hydrolysis condensation temperature is 35-60℃; In step S23, the AAO template is removed by soaking in a 5wt% phosphoric acid solution.

6. The microammonia latex medical examination glove according to claim 1, characterized in that, The first latex solution has a solid content of 30%-40%, and the amount of alkaline protease added is 0.01%-0.5% of the mass of the first latex solution; the micro-ammonia-deproteinized concentrated natural latex has a solid content of 60%-70%. The enzymatic hydrolysis reaction is carried out at a temperature of 30-45℃ for 3-8 hours.

7. The microammonia latex medical examination glove according to claim 1, characterized in that, The stabilizer is sodium dodecyl sulfate, and the amount added is 1%-3% of the mass of the fresh natural latex.

8. A method for preparing a microammonia latex medical examination glove according to any one of claims 1-7, characterized in that, include: Add 1-2.5 parts of sulfur, 0.5-1.5 parts of zinc oxide, 0.5-1.5 parts of accelerator, 1-2 parts of antioxidant, and 0.1-0.5 parts of surfactant to 100 parts of modified deproteinized natural concentrated latex. After mixing evenly, pour the mixture into a mold, dry, and vulcanize to obtain micro-ammonia latex medical examination gloves.

9. The method for preparing the microammonia latex medical examination glove according to claim 8, characterized in that, The vulcanization temperature is 90–110°C, and the time is 15–30 min.

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