Silicon-free anti-webbed agent for latex gloves as well as preparation method and application of silicon-free anti-webbed agent

Abstract

The invention relates to the technical field of functional aids, in particular to a silicon-free anti-webbed agent for latex gloves as well as a preparation method and application of the silicon-free anti-webbed agent. The invention relates to a silicon-free anti-webbing agent for latex gloves. The silicon-free anti-webbing agent comprises the following raw materials in percentage by weight: 5-15% of a raw material A, 5-15% of a raw material B, 5-10% of a raw material C and the balance of water, the raw material A is one or more of lipid and high-carbon alcohol; the raw material B is fatty acid; the raw material C comprises a pH regulator and fatty amine. The cloud point of the anti-webbed agent can reach 80.6-85.3 DEG C, the surface tension can reach 33.4-30.7 dynes / cm, and the anti-webbed agent is good in compatibility with a release agent salt solution and free of floating oil. The anti-webbing agent is completely and mutually soluble with natural latex and butyronitrile latex, and does not float oil at high temperature; the qualified rate of the latex gloves prepared from the anti-webbed agent disclosed by the invention can reach 97.5-99.8%.

Description

Technical Field

[0001] The present application relates to the technical field of functional auxiliaries, and particularly relates to a silicon-free anti-webbing agent for latex gloves, a preparation method thereof, and an application thereof. Background Art

[0002] China is a major producer of natural / nitrile latex gloves. The glove manufacturing process is very mature. The resins used are all natural resins produced in Malaysia or nitrile resins produced in Thailand, and the stability is guaranteed. The most influential factor on the yield of glove products is the defect of "webbing" formed on the rubber film.

[0003] The formation mechanism of "webbing" is as follows: When preparing thin-layer gloves, after the glove mold is immersed in the rubber solution and lifted out of the rubber solution surface instantaneously, a "webbing"-shaped liquid film will appear between the finger forks. After the "webbing" breaks, there will be uneven thickness or tiny holes at the finger forks. Even more seriously, there will be no rubber in some areas. The gloves made in this way will have thin spots, pinholes or even holes, which seriously affect the protective usability of the gloves. Such gloves are defective products. If defective gloves flow into the medical system, medical staff wearing poorly protective broken gloves are extremely likely to cause bacterial infections among medical staff, which is a serious medical accident.

[0004] In order to avoid or reduce the formation of "webbing", an anti-webbing agent will be added to the rubber solution. The commonly used anti-webbing agent, n-butanol, is not suitable for use in latex gloves because n-butanol is a volatile solvent and is likely to evaporate during the latex manufacturing process, which may cause changes in the composition of the latex mixture and affect the physical properties and chemical stability of the gloves. In addition, some silicone-containing defoamers, such as organosiloxane emulsion defoamers, polysiloxane-polyether copolymer defoamers, etc., can play a role in anti-webbing to a certain extent while defoaming.

[0005] In view of the above related technologies, the applicant believes that using the above-mentioned silicone-containing defoamers will leave some silicon elements on the latex gloves. Since latex gloves are not only used in the medical system but also in the electronics industry, electrical components are relatively sensitive to silicon elements, and silicon-containing gloves will have a negative impact on electrical components. Summary of the Invention

[0006] In order to solve the "webbing" defect in the production of latex gloves and avoid the influence of silicon on electrical components, the present application provides a silicon-free anti-webbing agent for latex gloves, a preparation method thereof, and an application thereof.

[0007] In a first aspect, the present application provides a silicon-free anti-webbing agent for latex gloves, adopting the following technical solution: A silicon-free anti-webbing agent for latex gloves, comprising the following raw materials in percentage by weight: Raw material A: 5-15%, Raw material B: 5-15%, Raw material C: 5-10%, and the balance is water; The raw material A is one or more of esters and higher alcohols; The raw material B is a fatty acid; The raw material C includes a pH regulator and a fatty amine.

[0008] By adopting the above technical solution, the lipid substances and higher alcohols in the anti-webbing agent can reduce the surface tension of the liquid and improve the fluidity of the latex; the fatty acid can play a lubricating role; the fatty amine can improve the compatibility between the anti-webbing agent and the latex. The cloud point of the anti-webbing agent in this application can reach above 80°C, the surface tension can reach below 33.4 dynes / cm and the viscosity is appropriate. It has good compatibility with the release agent salt solution, does not float oil, and completely and evenly wets the hand mold. It is completely miscible with natural latex and nitrile latex, does not float oil at high temperatures, does not cause shrinkage holes in the rubber film, and very successfully solves the "webbing" problem, enabling the customer's finished product rate to reach over 97%.

[0009] The lipid substance component is generally a glyceride substance containing long-chain saturated or unsaturated unit fatty acids, which has lipophilicity and hydrophilicity and can form a thin film at the gas-liquid interface to reduce the surface tension. It includes natural lipids and mineral oils, and natural lipids are used in this application.

[0010] Higher alcohols refer to alcohol compounds containing six or more carbon atoms, usually represented by the chemical formula CnH2n+1OH. They are a class of alcohols with high carbon chains. The physical properties of higher alcohols are manifested as colorless or slightly yellowish liquids with a special odor. They have low solubility in water but high solubility in organic solvents. Chemically, higher alcohols can undergo esterification, etherification and other reactions to form esters, ethers and acid derivatives. In industrial applications, higher alcohols are often used as solvents, lubricants and antifreeze agents, and are also raw materials for synthetic materials and surface lubricants. Higher alcohols can effectively control the foam problem in the latex processing process and ensure the production quality and efficiency of latex gloves. By adding higher alcohols, production problems caused by excessive foam, such as latex thickening, gelling, thickening or gelation, can be avoided, thus ensuring the stable production of latex gloves and improving product quality. In addition, the higher alcohol defoamer can still maintain good defoaming effect under high temperature conditions, which helps to stabilize the process, reduce the usage amount of the defoamer, and improve the quality of latex gloves at the same time.

[0011] Fatty acids are a class of compounds composed of carbon, hydrogen and oxygen elements. According to the number of double bonds in the carbon chain, fatty acids can be further divided into saturated fatty acids and unsaturated fatty acids. Fatty acids can reduce the interfacial tension between water and latex, promote the dispersion of latex particles in water, and form a stable emulsion; fatty acid molecules can adsorb on the surface of latex particles to form a protective film to prevent the aggregation and coagulation of latex particles and maintain the stability of the latex system; the addition of fatty acids can improve the processing performance of latex, such as increasing the fluidity of latex, reducing the viscosity during the processing process, making the latex easier to coat and form, thereby improving the production efficiency and quality of latex gloves.

[0012] Fatty amines refer to a large class of organic amine compounds with a carbon chain length in the range of C8-C22. Like general amines, they are divided into four categories: primary amines, secondary amines, tertiary amines, and polyamines. The primary, secondary, and tertiary amines depend on the number of hydrogen atoms in ammonia replaced by alkyl groups. Fatty amine molecules can adsorb on the surface of latex particles to form a protective film, which, in cooperation with fatty acids, further enhances the stability of the latex system and prevents the aggregation and coagulation of latex particles.

[0013] Furthermore, the weight ratio of raw material A: raw material B: raw material C is 1:(0.8-1.2):(0.5-1).

[0014] In some specific embodiments, the weight ratio of raw material A: raw material B: raw material C is any ratio within 1:(0.8-1.2):(0.5-1). For example, in some specific embodiments, the weight ratio of raw material A: raw material B: raw material C is 1:0.8:1; in some specific embodiments, the weight ratio of raw material A: raw material B: raw material C is 1:1.2:0.5; in some specific embodiments, the weight ratio of raw material A: raw material B: raw material C is 1:1:0.7.

[0015] Furthermore, raw material A includes lipids and higher alcohols with a weight ratio of (10-25):1.

[0016] In some specific embodiments, raw material A includes lipids and higher alcohols with any ratio within (10-25):1. For example, in some specific embodiments, raw material A includes lipids and higher alcohols with a weight ratio of 10:1; in some specific embodiments, raw material A includes lipids and higher alcohols with a weight ratio of 18:1; in some specific embodiments, raw material A includes lipids and higher alcohols with a weight ratio of 25:1.

[0017] Furthermore, the lipids in raw material A include one or more of castor oil, palm fat, coconut oil, and lanolin; The higher alcohols in raw material A include one or more of dodecanol, octadecanol, and docosanol.

[0018] The lipids in the anti-web agent of this application are defined as one or more of castor oil, palm fat, coconut oil, and lanolin. Castor oil is a vegetable oil extracted from castor seeds, and its main component is ricinoleic acid, which is an uncommon monounsaturated fatty acid. Palm fat is a vegetable oil extracted from the pulp of oil palm fruits and is mainly composed of saturated fatty acids and monounsaturated fatty acids. Coconut oil is a vegetable oil extracted from the pulp of coconuts and is mainly composed of medium-chain saturated fatty acids. Lanolin is a natural fat substance extracted from the wool of sheep. It is mainly composed of esters of fatty acids and alcohols and has good moisturizing and emollient properties.

[0019] Further, the fatty acid includes saturated fatty acid and unsaturated fatty acid; The saturated fatty acid includes one or more of stearic acid, ricinoleic acid, and pelargonic acid; The unsaturated fatty acid includes one or more of linolenic acid and oleic acid.

[0020] Further, the weight ratio of the pH regulator to the fatty amine in the raw material C is 1:(30 - 40).

[0021] Further, the pH regulator includes one or more of natural soda, small molecule basic substances, and amine salts; The small molecule basic substances include one or more of triethylamine, trimethylamine, and dimethylacetamide; The amine salt includes octylamine salt.

[0022] In a second aspect, the present application provides a preparation method of a silicon-free anti-web agent for latex gloves, adopting the following technical solution: A preparation method of a silicon-free anti-web agent for latex gloves includes the following steps: S1. Mix raw material A, raw material B, and raw material C and heat them to melt to obtain a preliminary mixture; S2. Heat water to 80 - 90 °C; S3. Under stirring, add the preliminary mixture obtained in S1 above to the water heated in S2, and mix evenly to obtain a mixture; S4. Cool the mixture obtained in S3 above to 25 - 30 °C, and filter it through a 200-mesh filter screen to obtain a silicon-free anti-web agent.

[0023] In a third aspect, the present application provides a preparation process of latex gloves, adopting the following technical solution: A preparation process of latex gloves includes the following steps: washing the hand mold, drying, dipping in a coagulation bath, drying again, dipping in latex, vulcanizing, anti-sticking and isolation treatment, and demolding; any one of the above silicon-free anti-web agents for latex gloves is added to the latex in the latex dipping step, and the addition amount of the anti-web agent is 0.08 - 0.015% of the latex.

[0024] Further, the dipping bath in the coagulation bath dipping step includes a gel and a surfactant, the surfactant is a surfactant with a cloud point higher than 70 °C, and the addition amount of the surfactant is 0.15 - 0.25% of the gel.

[0025] In some embodiments, the surfactant is one or more of isomeric tridecanol and isomeric nonanol.

[0026] In summary, the present application has the following beneficial effects: The cloud point of the anti-web agent obtained by the present application through specific raw materials and ratios can reach 80.6 - 85.3 °C, the surface tension can reach 33.4 - 30.7 dynes / cm, and it has good compatibility with the release agent salt solution without floating oil; the anti-web agent of the present application is completely miscible with natural latex and nitrile latex and does not float oil at high temperatures; the qualification rate of the latex gloves prepared with the anti-web agent of the present application can reach 97.5 - 99.8%. Detailed Description of the Invention

[0027] The following further elaborates on the present application in conjunction with the embodiments.

[0028] Raw Materials The raw materials in the embodiments of the present application can all be obtained commercially:[[]] Coconut oil, analytical pure, with the molecular formula C 10 H 12 O4; Stearyl alcohol, analytical pure, with the molecular formula C 18 H 38 O; Stearic acid, analytical pure, analytical pure C 18 H 36 O2, flash point 235°F; water solubility: 0.5 g / 100 mL at 23 °C; Linolenic acid, analytical pure, α-linolenic acid, with the molecular formula CH3-(CH2CH=CH)3-(CH2)7COOH Trona, analytical pure, with the molecular formula Na2CO3·NaHCO3·2H2O; Stearylamine, analytical pure, with the molecular formula C 18 H 39 N; Castor oil, mainly composed of fatty acid glycerides, with the content of ricinoleic acid being 85%, and the rest being other fatty acids such as oleic acid, linoleic acid, palmitic acid, and stearic acid; Palm fat, palmitic acid glyceride formed by the reaction of palmitic acid and glycerol; Dodecanol, analytical pure, with the molecular formula C 12 H 26 O; Lanolin, chemical name hexadecyl stearate, with the chemical formula C 44 H 88 O2; Docosanol, analytical pure, with the molecular formula C 22 H 46 O; Dimethylacetamide, analytical pure, with the molecular formula C4H9NO; Octylamine nitrate, an organic compound, with the chemical formula C8H 19NO3, formed by the reaction of octylamine (a primary amine with the chemical formula C8H19N) and nitric acid; Stearylamine, also known as hexadecylamine, analytical pure, with the molecular formula C 16 H 35 N. Examples

[0029] Examples 1 - 7 A silicon - free anti - webbing agent for latex gloves, and its preparation method is as follows: S1. Mix raw material A, raw material B, and raw material C according to the raw material ratio in Table 1 and heat until all raw materials are melted to obtain a preliminary mixture; S2. Heat water to 80 °C; S3. Under stirring, add the preliminary mixture obtained in S1 above to the water heated in S2, and mix evenly to obtain a mixture; S4. Cool the mixture obtained in S3 above to 27 °C and filter it through a 200 - mesh filter to obtain the silicon - free anti - webbing agent.

[0030] Table 1 Raw material ratio table for Examples 1 - 7 (kg)

[0031] Among them, raw material A is coconut oil and stearyl alcohol with a weight ratio of 15:1; raw material B is stearic acid and linolenic acid with a weight ratio of 6:1; raw material C is natural alkali and stearylamine with a weight ratio of 1:35.

[0032] Example 8 Different from Example 2, in Example 8, raw material A is castor oil, palm fat, and dodecanol with a weight ratio of 5:5:1.

[0033] Example 9 Different from Example 2, in Example 9, raw material A is lanolin and docosanol with a weight ratio of 25:1.

[0034] Example 10 Different from Example 2, in Example 10, raw material C is natural alkali, dimethylacetamide, octylamine nitrate, and stearylamine with a weight ratio of 1:1:1:90.

[0035] Example 11 Different from Example 2, in Example 11, in step S2, heat the hot water to 85 °C.

[0036] Example 12 Different from Example 2, in Example 12, in step S2, heat the hot water to 87 °C.

[0037] Example 13 Different from Example 2, in step S2 of Example 13, the hot water is heated to 90 °C.

[0038] Example 14 Different from Example 2, in step S2 of Example 14, the hot water is heated to 95 °C.

[0039] Comparative Example Comparative Example 1 Different from Example 1, the raw material ratio in Comparative Example 1 is: 25 kg of raw material A, 15 kg of raw material B, 10 kg of raw material C, and 50 kg of water.

[0040] Comparative Example 2 Different from Example 1, the raw material ratio in Comparative Example 2 is: 5 kg of raw material A, 25 kg of raw material B, 10 kg of raw material C, and 60 kg of water.

[0041] Comparative Example 3 Different from Example 1, the raw material ratio in Comparative Example 3 is: 5 kg of raw material A, 15 kg of raw material B, 15 kg of raw material C, and 65 kg of water.

[0042] Performance Detection The cloud point, surface tension, and compatibility with the mold release agent of the anti-web agent in the examples and comparative examples were detected, and the detection results are shown in Table 2.

[0043] Detection method of cloud point: 1. Preparation of water: ether solution Prepare a water: ether solution according to water: ether = 2:1 (mass ratio) for later use; 2. Sample preparation Take 5 grams of the anti-web agent and dissolve it in 95 grams of the water: ether solution, and stir until transparent (the temperature should be lower than 25 °C); 3. Measure 20 ml of the above solution, place it in a test tube, insert a thermometer, heat it in a water bath, gently stir with the thermometer until the solution becomes completely turbid (the solution temperature does not exceed 5 °C of the turbidity temperature), stop heating, take out the test tube, cool it while stirring with the thermometer, record the temperature when the turbidity completely disappears, repeat the experiment three times, the difference between the three parallel results is not more than 0.5 °C, and take the arithmetic mean as the cloud point measurement.

[0044] Detection method of surface tension: Detect using a KRUSS BPT dynamic tensiometer; The detection method for compatibility with the mold release agent is: Mix the anti-web agent with the mold release agent (a fine paste substance with calcium stearate as the main mold release component), and then observe the appearance change of the mixed solution.

[0045] Table 2 Performance Detection Results of Anti-Web Agent

[0046] Combining Examples 1-14 with Comparative Examples 1-3 and referring to Table 2, it can be seen that the cloud points of the anti-web agents in Examples 1-14 are all higher than those in Comparative Examples 1-3, and the surface tensions of the anti-web agents in Examples 1-14 are all lower than those in Comparative Examples 1-3.

[0047] Combining Examples 1-7 with Comparative Examples 1-3 and referring to Table 2, it can be seen that the change in the ratio of Raw Material A, Raw Material B, and Raw Material C will affect the performance of the anti-web agent. Among them, the ratios of Raw Material A, Raw Material B, and Raw Material C in Comparative Examples 1-3 exceed the ratio range defined in this application. Then, the cloud point of the anti-web agent in Comparative Examples 1-3 is significantly lower than that in Examples 1-7, and the surface tension is significantly higher than that in Examples 1-7. This shows that an anti-web agent with a high cloud point and a low surface tension can be obtained within the range defined in this application. In addition, the performances of the anti-web agents in Examples 1-7 are all relatively excellent, and the ratio in Example 2 is more excellent.

[0048] Combining Example 2 with Examples 11-14 and referring to Table 2, it can be seen that the preparation temperature of the anti-web agent will affect the performance of the anti-web agent. When the temperature is 80-90 °C, the requirements of this application can be met. Among them, when the temperature is 80-85 °C, the performance of the obtained anti-web agent is more excellent. This may be because the reaction is complete within this temperature range without causing high-temperature yellowing.

[0049] Application Example Application Example 1 A latex glove, the preparation process of which includes the following steps: S1. Wash the hand mold Clean the surface of the hand mold to ensure that the surface of the hand mold is clean and free of impurities; S2. Dry Dry the washed hand mold at 80 °C to ensure that the surface of the hand mold is dry; S3. Immerse in the coagulation bath Immerse the hand mold into the mixing liquid tank of the gelling agent and the release agent (a delicate paste substance with calcium stearate as the main release component) to coat a layer of gelling agent and form a uniform gel film on the hand mold; the addition amount of the release agent is 0.2% of the gelling agent; S4. Dry again Use the oven to dry the hand mold that has been coated with a layer of gelling agent again to ensure that the gelling agent is completely cured; S5. Immerse in latex Immerse the glove forming mold into the latex tank formed by mixing natural latex and the anti-web agent obtained in Example 1 to coat latex, and then use the oven to dry it to form a preliminary form of the latex glove; the mixed liquid in the latex tank is heated to 55 °C, and the addition amount of the anti-web agent is 0.1% of the natural latex; S6. Vulcanize Heat vulcanize the preliminarily formed latex glove film; S7. Anti-sticking and isolation treatment Coat the glove with a polymer for anti-sticking to prevent the inner layers of the glove from sticking together during demolding, ensuring that the glove is easy to demold and has a smooth surface; S8. Demolding; Completely separate the glove from the glove forming mold to form the final shape of a general latex glove.

[0050] Application Example 2-14 Different from Application Example 1, the anti-web agents in Application Examples 2-14 are respectively from Examples 2-14.

[0051] Application Example 15 Different from Application Example 2, isononyl alcohol surfactant is further added to the mixed solution in step S3 of Application Example 15, and the addition amount of the surfactant is 0.2% of the gelling agent.

[0052] Application Example 16 Different from Application Example 2, natural rubber is replaced with an equal amount of nitrile latex in Application Example 16.

[0053] Comparative Application Example Comparative Application Examples 1-3 Different from Application Example 1, the anti-web agents in the comparative application examples are respectively from Comparative Examples 1-3.

[0054] Performance detection Observe the mixed solution in the latex tank in S3 after heating, and record its appearance state. The results are shown in Table 3.

[0055] Detect the qualified rate of the produced latex gloves. Professional personnel check the produced latex gloves and screen out unqualified products. The unqualified products include uneven rubber film between finger forks, thickness not meeting the requirements, thin spots, holes, etc. Calculate the qualified rate: .

[0056] Table 3 Performance detection results

[0057] It can be seen from Table 3 that the anti-web agent of the present application is completely miscible in natural latex and chemical latex and does not float oil at high temperature. After using the anti-web agent of the present application, the qualified rate of producing latex gloves can reach 97.5-99.8%. This may be because the anti-web agent of the present application has a low surface tension, completely and evenly wets the hand mold, is completely miscible with natural latex and nitrile latex, does not float oil at high temperature, does not cause shrinkage holes in the rubber film, and successfully solves the "web formation" defect, improving the product qualified rate.

[0058] This specific embodiment is only an interpretation of the present application and does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment that do not contribute creatively as needed, but as long as it is within the scope of the claims of the present application, it is protected by the patent law. It is protected by the patent law as long as it is within the scope of the claims.

Claims

1. A silicon-free anti-webbing agent for latex gloves, characterized in that: The invention comprises the following raw materials in weight percentage: raw material A: 5-15%, raw material B: 5-15%, raw material C: 5-10%, and the balance is water; The raw material A is one or more of lipids and higher alcohols; The raw material B is fatty acid; The raw material C includes a pH regulator and a fatty amine.

2. The non-silicone anti-webbing agent for latex gloves according to claim 1, characterized in that: The weight ratio of the raw material A: raw material B: raw material C is 1: (0.8-1.2): (0.5-1).

3. The non-silicone anti-webbing agent for latex gloves according to claim 1, characterized in that: The raw material A comprises lipids and high carbon alcohols in a weight ratio of (10-25):

1.

4. The silicon-free anti-webbing agent for latex gloves according to claim 1, characterized in that: The lipids in the raw material A include one or more of castor oil, palm fat, coconut oil, and lanolin; The higher carbon alcohol in the raw material A includes one or more of dodecanol, octadecyl alcohol and behenyl alcohol.

5. The non-silicone anti-webbing agent for latex gloves according to claim 1, characterized in that: The fatty acids include saturated fatty acids and unsaturated fatty acids; The saturated fatty acid includes one or more of stearic acid, ricinoleic acid, and nonanoic acid; The unsaturated fatty acids include one or more of linolenic acid and oleic acid.

6. The silicon-free anti-webbing agent for latex gloves according to claim 1, characterized in that: The weight ratio of the pH regulator to the fatty amine in the raw material C is 1:(30-40).

7. The non-silicone anti-webbing agent for latex gloves according to claim 1, characterized in that: The pH adjuster includes one or more of natural alkali, small molecule alkaline substances, and amine salts; The small molecule alkaline substance includes one or more of triethylamine, trimethylamine, and dimethylacetamide; The amine salt is an octylamine salt.

8. A method for preparing the silicon-free anti-webbing agent for latex gloves according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Mix raw material A, raw material B, and raw material C and heat to melt to obtain an initial mixed solution; S2. Heat the water to 80-90°C; S3. Under stirring, the initial mixed solution obtained in S1 is added to the heated water in S2 and mixed to obtain a mixture; S4. The mixture obtained in the above S3 is cooled to 25-30° C. and filtered through a 200-mesh filter to obtain a silicon-free anti-webbing agent.

9. A process for preparing latex gloves, comprising the following steps: Washing the hand mold, drying, dipping in a coagulation bath, drying again, dipping in latex, vulcanizing, anti-sticking isolation treatment, and demoulding; characterized in that the silicon-free anti-webbing agent for latex gloves according to any one of claims 1 to 7 is added to the latex in the latex dipping step, and the amount of the anti-webbing agent added is 0.08-0.015% of the latex.

10. The process for preparing latex gloves according to claim 9, characterized in that: The immersion bath in the coagulation bath immersion step comprises gel and a surfactant, wherein the surfactant has a turbidity point higher than 70° C. and the added amount of the surfactant is 0.15-0.25% of the gel.

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