Micro-ammonia latex medical examination glove and preparation method thereof

Abstract

The invention 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. Comprising 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 an accelerant, 1-2 parts of an antioxidant and 0.1-0.5 part of a surfactant, the preparation method of the modified deproteinized natural concentrated latex comprises the following steps: filtering fresh natural latex to remove impurities, supplementing ammonia to 0.05-0.1%, then adding a stabilizer, porous rod-like silicon dioxide and alkaline protease, and carrying out an enzymolysis reaction; centrifuging to obtain micro-ammonia deproteinized concentrated natural latex and porous rod-like silicon dioxide, washing the porous rod-like silicon dioxide with water, and mixing with the micro-ammonia deproteinized concentrated natural latex to obtain the micro-ammonia deproteinized concentrated natural latex. The protein removal rate is improved through the shearing and friction effects of the porous rod-like silicon dioxide, and the porous rod-like silicon dioxide is further used as a reinforcing agent to improve the mechanical properties of the gloves.

Description

TECHNICAL FIELD

[0001] 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. BACKGROUND

[0002] Medical latex gloves, as indispensable protective equipment in the medical field, are widely used in operations such as surgery, nursing and examination. The main function of medical latex gloves is to establish a physical barrier to prevent cross-infection between medical staff and patients, and to protect medical staff from chemical substances and pathogens. At present, medical latex gloves are mainly made of natural rubber latex as the main raw material, and are prepared by processes such as dip molding and vulcanization crosslinking. Medical latex gloves have excellent elasticity, flexibility, fit and biocompatibility, and have dominated the medical protection field for a long time.

[0003] However, there are still two major problems in the actual application of existing natural rubber-based medical latex gloves, which seriously restrict their safety and reliability: First, the risk of allergic reaction is high. Natural rubber latex contains various proteins, lipids and residual chemicals (such as vulcanization accelerators and anti-aging agents), which may cause abnormal reactions of the human immune system. Clinical studies have shown that the probability of allergic reaction in medical staff, as long-term and high-frequency users, is significantly higher than that in the general population, mainly manifested as contact dermatitis (delayed allergic reaction), urticaria and even anaphylactic shock (immediate allergic reaction). Although existing technologies can reduce the protein content through latex centrifugal purification and enzymatic treatment, it is still difficult to efficiently eliminate the allergic risk, especially for the protection of high-sensitivity groups.

[0004] Second, the mechanical strength and the matching of the use demand are insufficient. Medical latex gloves need to meet the requirements of tensile strength, tear strength, wear resistance and other mechanical properties to cope with complex medical operation scenarios (such as holding surgical instruments and repeated bending and stretching actions). The strength of existing natural latex gloves mainly depends on the vulcanization crosslinking network of rubber molecular chains, but the crosslinking density distribution is uneven, and the local strength is weak due to the fluctuation of film thickness and the difference in vulcanization degree during processing. In actual use, gloves often fail prematurely due to tearing at the fingertips and finger joints, which not only increases the medical cost, but also may cause exposure risk due to damaged protection. In addition, in order to pursue good fit and comfort, existing gloves are often designed to be thin (thickness is usually 0.08-0.15mm), which further aggravates the problem of insufficient strength; while simply increasing the thickness can improve the strength, it will lead to decreased flexibility and affect the accuracy of delicate operations.

[0005] Therefore, developing a medical latex glove which can reduce the risk of allergy, significantly improve the mechanical strength and maintain excellent elasticity and comfort has become a technical problem to be solved in the field. SUMMARY

[0006] The present application aims to provide a micro-ammonia latex medical examination glove and a preparation method thereof. By adding porous rod-like silicon dioxide in the enzymatic process, the shearing action of the porous rod-like silicon dioxide on rubber hydrocarbon particles in the stirring process is utilized to improve the dissociation efficiency of proteins, thereby assisting in improving the removal rate of proteins. At the same time, the recovered porous rod-like silicon dioxide is used again as a reinforcing filler for the latex glove, which can improve its strength, achieve two goals at once, and fully utilize raw materials, with strong industrial applicability.

[0007] To achieve the above-mentioned purpose, the present application provides a micro-ammonia latex medical examination glove, the raw materials of which include: modified deproteinized natural concentrated latex 100 parts, sulfur 1-2.5 parts, zinc oxide 0.5-1.5 parts, accelerator 0.5-1.5 parts, antioxidant 1-2 parts and surfactant 0.1-0.5 parts. The preparation method of the modified deproteinized natural concentrated latex includes: S1, filtering the fresh natural latex to remove impurities and clots, supplementing ammonia to a mass fraction of 0.05-0.1%, then adding a stabilizer to obtain a first latex solution; S2, adding porous rod-like silicon dioxide and alkaline protease to the first latex solution, and performing enzymatic reaction while stirring, to improve the removal rate of proteins by utilizing the shearing and friction of the porous rod-like silicon dioxide, to obtain a second latex solution; S3, centrifuging the second latex solution to obtain micro-ammonia deproteinized concentrated natural latex in the upper layer and porous rod-like silicon dioxide in the lower layer, 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.

[0008] Further, in step S2, the alkaline protease is first dissolved in water, then the porous rod-like silicon dioxide is added for impregnation and adsorption, and then the mixed solution is added to the first latex solution.

[0009] Further, the length of the porous rod-like silicon dioxide is 0.3-1 µm, and the diameter is 50-100 nm; the addition amount of the silicon dioxide particles is 5%-10% of the mass of the first latex solution.

[0010] Further, the preparation method of the porous rod-like silicon dioxide includes: S21, adding tetraethyl orthosilicate to a mixed solution of water and ethanol containing cetyltrimethylammonium bromide, and then adding hydrochloric acid to control the pH value to 2-4 to obtain a silica sol; S22, place the AAO template in the silica sol, and perform hydrolysis and condensation; then take out the template, heat to 120-160 DEG C, and heat treat for 0.5-3h; the pore size of the AAO template is 50-200nm, and the pore depth is 0.5-2µm; S23, remove the AAO template by dissolution, centrifuge, wash, dry, then calcine at 500-600 DEG C to remove the cetyltrimethylammonium bromide, and obtain porous rod-shaped silica.

[0011] Further, in step S23, a vinyl silane coupling agent is used to perform hydrolysis and condensation with the porous rod-shaped silica to obtain vinyl silane coupling agent modified porous rod-shaped silica, and then isoprene is used to perform free radical polymerization with the vinyl silane coupling agent to obtain modified porous rod-shaped silica.

[0012] Further, in step S21, the volume ratio of water and ethanol is 1: (3-5); and the addition amount of the cetyltrimethylammonium bromide is 10%-15% of the tetraethyl orthosilicate. In step S22, the temperature of the hydrolysis and condensation is 35-60 DEG C. In step S23, the AAO template is removed by immersion in a 5wt% phosphoric acid solution.

[0013] Further, the solid content of the first latex solution is 30%-40%, the addition amount of the alkaline protease is 0.01%-0.5% of the mass of the first latex solution; and the solid content of the micro-ammonia deproteinized concentrated natural latex is 60%-70%. The temperature of the enzymatic reaction is 30-45 DEG C, and the time is 3-8h.

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

[0015] The application also provides a preparation method of the micro-ammonia latex medical examination glove, comprising: adding sulfur 1-2.5 parts, zinc oxide 0.5-1.5 parts, accelerator 0.5-1.5 parts, antioxidant 1-2 parts, and surfactant 0.1-0.5 parts into 100 parts of the modified deproteinized natural concentrated latex, uniformly mixing, pouring into a mold, drying, and vulcanizing to obtain the micro-ammonia latex medical examination glove.

[0016] Further, the vulcanization temperature is 90-110 DEG C, and the time is 15-30min.

[0017] Overall, compared with the prior art, the above technical solutions conceived by the application mainly have 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 a mass fraction of 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, centrifuging the second latex solution to obtain micro-ammonia deproteinized concentrated natural rubber on the top layer and porous rod-shaped silicon dioxide on the bottom layer, mixing the porous rod-shaped silicon dioxide after water washing with the micro-ammonia deproteinized concentrated natural rubber to obtain the micro-ammonia deproteinized concentrated natural rubber.

[0023] In this way, the sharp end of the rod-shaped silicon dioxide can be used to improve the shearing effect on the rubber hydrocarbon particles, destroy the surface protein adsorption layer, and at the same time, the porous structure can adsorb moisture, change the local osmotic pressure of the latex, and thus promote the expansion of the rubber hydrocarbon particles, stretch the protein adsorption layer, and further promote the shedding of loosely bound proteins, thereby improving the protein removal rate. After enzymatic hydrolysis of the proteins, the separated porous rod-shaped silicon dioxide is washed with water to remove the adsorbed proteins or enzymatic hydrolysis products, and 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, and at the same time, the porous structure helps the rubber molecules to embed and improve the anchoring effect between them, thereby improving the strength.

[0024] Further, in step S2, the alkaline protease is first dissolved in water, then the porous rod-shaped silicon dioxide is added for impregnation and adsorption, and then the mixed solution is added to the first latex solution. In this way, the alkaline protease is adsorbed in the pores, which helps to enzymatically hydrolyze the proteins adsorbed in the pores, effectively reducing the proteins in the porous rod-shaped silicon dioxide after subsequent water washing.

[0025] Further, the length of the porous rod-shaped silicon dioxide is 0.3-1 µm, and the diameter is 50-100 nm; the addition amount of the silicon dioxide particles is 5%-10% of the mass of the first latex solution.

[0026] Further, the preparation method of the porous rod-shaped silicon dioxide comprises: S21, adding tetraethyl orthosilicate to a mixed solution of water and ethanol containing cetyltrimethylammonium bromide, and then adding hydrochloric acid to control the pH value to 2-4 to obtain a silica sol; S22, placing an AAO (anodic aluminum oxide) template in the silica sol for hydrolysis and condensation; then taking out the template and heating to 120-160°C for 0.5-3h for heat treatment; the pore size of the AAO template is 50-200 nm, and the pore depth is 0.5-2 µm; S23, removing the AAO template by dissolution, centrifugation, washing, drying, and then calcining at 500-600°C to remove cetyltrimethylammonium bromide to obtain the porous rod-shaped silicon dioxide.

[0027] In step S23, the porous rod-like silica is modified by hydrolysis condensation of vinyl silane coupling agent, and then free radical polymerization of isoprene and vinyl silane coupling agent to obtain the modified porous rod-like silica. In this way, the compatibility of the porous rod-like silica and the rubber hydrocarbon particles is increased, and the mechanical strength is improved through chemical bonding and molecular entanglement. The mass ratio of vinyl triethoxysilane, isoprene and porous rod-like silica is 1: (3-6): 10.

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

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

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

[0031] The application also provides a preparation method of the micro-ammonia latex medical examination glove, comprising: adding sulfur 1-2.5 parts, zinc oxide 0.5-1.5 parts, accelerator 0.5-1.5 parts, antioxidant 1-2 parts and surfactant 0.1-0.5 parts into 100 parts of modified deproteinized natural concentrated latex, uniformly mixing, pouring into a mold, drying, and vulcanizing to obtain the micro-ammonia latex medical examination glove.

[0032] Further, the vulcanization temperature is 90-110℃, and the time is 15-30min.

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

[0034] The preparation method of the modified deproteinized natural concentrated latex comprises: S1, filtering the fresh natural latex to remove impurities and clots, adding ammonia to a mass fraction of 0.06%, and then adding a stabilizer sodium dodecyl sulfate 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, mixing porous rod-shaped silica (added in an amount of 7% of the mass of the first latex solution) and an aqueous solution of alkaline protease (added in an amount of 0.1% of the mass of the first latex solution) uniformly, and then adding them to the first latex solution, stirring (stirring speed of 200 r / min) and performing enzymatic reaction for 5 h, using the shearing and friction of the porous rod-shaped silica to improve the removal rate of proteins, to obtain a second latex solution; S3, centrifuging the second latex solution to obtain micro-ammonia deproteinized concentrated natural latex in the upper layer and porous rod-shaped silica in the lower layer, mixing the washed porous rod-shaped silica with the micro-ammonia deproteinized concentrated natural latex (solid content of 65%) to obtain the micro-ammonia deproteinized concentrated natural latex.

[0035] The preparation method of the porous rod-shaped silica comprises the following steps: S21, adding tetraethyl orthosilicate to a mixed solution of water and ethanol (volume ratio of 1:4) containing cetyltrimethylammonium bromide (added in an amount of 12% of the mass of the tetraethyl orthosilicate), and then adding hydrochloric acid to control the pH value to 3 to obtain a silica sol; S22, placing an AAO (anodic aluminum oxide) template in the silica sol to perform hydrolysis and condensation, and then taking out the template, heating to 140°C and heat treating for 1 h; the pore diameter of the AAO template is 80 nm, and the pore depth is 0.6 µm; S23, dissolving and removing the AAO template by using a 5 wt% phosphoric acid solution, centrifuging, washing, drying, and then calcining at 550°C to remove cetyltrimethylammonium bromide to obtain the porous rod-shaped silica.

[0036] Example 2 The difference from Example 1 is that in step S23, vinyltriethoxysilane is used to hydrolyze and condense with the porous rod-shaped silica to obtain porous rod-shaped silica modified by a vinyl silane coupling agent, and then free radical polymerization is performed between isoprene and the vinyl silane coupling agent to obtain the modified porous rod-shaped silica. The mass ratio of the vinyltriethoxysilane, the isoprene and the porous rod-shaped silica is 1:5:10. The other steps are the same as those in Example 1 and will not be repeated here.

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

[0038] Comparative Example 1 The difference between Example 2 and Example 3 is that the amount of porous rod-like silica added in step S2 is 2% of the mass of the first latex solution.

[0039] Comparative Example 2 The difference between Example 2 and Comparative Example 2 is that no cetyltrimethylammonium bromide is added in step S21.

[0040] Comparative Example 3 The difference between Example 2 and Comparative Example 3 is that the length of the silica particles is 200 nm and the diameter is 80 nm. Other than that, it is the same as Example 2, which will not be repeated here.

[0041] The prepared deproteinized natural rubber latex is sampled according to the provisions of ISO 123. A culture dish of polypropylene material with an inner diameter of 90 mm is selected, and the culture dish is placed horizontally on a horizontal support. A certain amount of natural rubber latex is poured into the culture dish to evenly spread and cover the culture dish bottom, and then it is naturally dried at room temperature until it is transparent. The finished film is peeled off from the culture dish bottom, and the thickness of the dried rubber film is 0.3±0.05 mm. The protein content extracted by water is determined according to the method described in ASTM D5712.

[0042] The mechanical stability of the obtained deproteinized natural rubber latex is determined according to the method for determining the mechanical stability of natural rubber latex described in ISO 35. The tensile properties are tested according to the test standard GB / T528-2009.

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

[0044] As can be seen from Table 1, when a suitable amount of porous rod-like silica is added to assist enzymatic hydrolysis, the protein content is significantly reduced. When the amount of porous rod-like silica is reduced in Comparative Example 1, the protein content increases, indicating that the porous rod-like silica helps to dissociate and remove the protein. At the same time, adding a suitable amount of porous rod-like silica can also improve the strength. When the porous structure is not used, the protein content increases and the tensile strength decreases, indicating that the porous structure is also beneficial to the removal of protein and the improvement of strength. When the vinyl silane coupling agent and isoprene are modified, the protein content is the lowest and the strength is the highest, indicating that the modified material has better protein adsorption, and the compatibility and entanglement with rubber are stronger.

[0045] Those skilled in the art will readily understand that the above description is only the preferred embodiment of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A micro-ammonia latex medical examination glove characterized by, The raw materials include: modified deproteinized natural concentrated latex 100 parts, sulfur 1-2.5 parts, zinc oxide 0.5-1.5 parts, accelerator 0.5-1.5 parts, antioxidant 1-2 parts and surfactant 0.1-0.5 parts; The preparation method of the modified deproteinized natural concentrated latex comprises: S1, filtering the fresh natural latex to remove impurities and clots, adding ammonia to a mass fraction of 0.05~0.1%, and then adding a stabilizer to obtain a first latex solution; S2, adding porous rod-shaped silica and alkaline protease to the first latex solution, and performing enzymatic reaction while stirring, and using the shearing and friction of the porous rod-shaped silica to improve the removal rate of protein, to obtain a second latex solution; S3, centrifuging the second latex solution to obtain micro-ammonia deproteinized concentrated natural latex in the upper layer and porous rod-shaped silica in the lower layer, and mixing the washed porous rod-shaped silica with the micro-ammonia deproteinized concentrated natural latex to obtain the micro-ammonia deproteinized concentrated natural latex.

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

3. The micro-urea latex medical examination glove according to claim 1, wherein, The length of the porous rod-shaped silica is 0.3-1µm, and the diameter is 50-100nm; the addition amount of the silica particles is 5%-10% of the mass of the first latex solution.

4. The micro- ammonium emulsion medical examination glove according to claim 3, characterized in that, The preparation method of the porous rod-shaped silica comprises: S21, adding tetraethyl orthosilicate to a mixed solution of water and ethanol containing cetyltrimethylammonium bromide, and then adding hydrochloric acid to control the pH value to 2-4 to obtain a silica sol; S22, placing an AAO template in the silica sol to perform hydrolysis and condensation; then taking out the template and heating to 120-160℃ for heat treatment for 0.5-3h; the pore diameter of the AAO template is 50-200nm, and the pore depth is 0.5-2µm; S23, removing the AAO template by dissolution, centrifuging, washing, drying, and then calcining at 500-600℃ to remove cetyltrimethylammonium bromide to obtain porous rod-shaped silica.

5. The micro-urea latex medical examination glove according to claim 4, wherein, In step S23, a vinyl silane coupling agent is used to hydrolyze and condense with the porous rod-shaped silica to obtain vinyl silane coupling agent modified porous rod-shaped silica, and then isoprene is used to free radical polymerize with the vinyl silane coupling agent to obtain modified porous rod-shaped silica.

6. The micro-urea latex medical examination glove according to claim 4, wherein, In step S21, the volume ratio of water to ethanol is 1: (3-5); the addition amount of cetyltrimethylammonium bromide is 10%-15% of the amount of tetraethyl orthosilicate; In step S22, the temperature of the hydrolysis and condensation is 35-60℃; In step S23, the AAO template is removed by soaking in a 5wt% phosphoric acid solution.

7. The micro-urea latex medical examination glove according to claim 1, wherein, The solid content of the first latex solution is 30%-40%, and the addition amount of the alkaline protease 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 reaction is 30-45℃, and the time is 3-8h.

8. The micro-urea latex medical examination glove according to claim 1, wherein, The stabilizer is sodium dodecyl sulfate, and the adding amount is 1%-3% of the mass of the fresh natural latex.

9. A process for the preparation of a medical examination glove of micro- ammonia emulsion according to any one of claims 1 to 8, characterized in that, Comprise: Sulfur 1-2.5 parts, zinc oxide 0.5-1.5 parts, accelerator 0.5-1.5 parts, antioxidant 1-2 parts and surfactant 0.1-0.5 parts are added into 100 parts of modified deproteinized natural concentrated latex, mixed uniformly, then poured into a mold, dried, vulcanized to obtain micro-ammonia latex medical examination gloves.

10. The method of claim 9, wherein the micro-urea latex medical examination glove is prepared by the steps of: The vulcanization temperature is 90-110℃, and the time is 15-30min.

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