Carboxyl nitrile latex for high-strength wear-resistant nitrile gloves and preparation method thereof

Abstract

The present application relates to the technical field of polymer material synthesis, and specifically discloses a carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves and a preparation method thereof. A carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves comprises component A, component B, and component C; component A comprises the following raw materials, based on the total weight of component A: emulsifier A, methacrylic acid, a molecular weight regulator, and acrylonitrile; component B comprises the following raw materials, based on the total weight of component B: emulsifier B, an initiator, and deionized water; and component C is emulsifier C, based on the total weight of component B. The present application obtains a carboxyl nitrile latex with a maximum bound nitrile content of 42.0%, thereby increasing the bound nitrile content of the carboxyl nitrile latex. The tear resistance and abrasion resistance of the nitrile gloves impregnated with the carboxyl nitrile latex reach levels 5 and 4, respectively, thereby improving the abrasion resistance and strength of the nitrile gloves.

Description

Technical Field

[0001] The present application relates to the technical field of polymer material synthesis, and more specifically, to a carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves and a preparation method thereof. Background Art

[0002] Carboxylated nitrile latex is primarily derived from the polymerization of butadiene, acrylonitrile, methacrylic acid, and other additives. Because the copolymer contains nitrile and carboxyl groups, carboxylated nitrile latex exhibits superior film-forming properties, oil resistance, and chemical resistance compared to standard nitrile latex. It also exhibits self-crosslinking properties, making it a popular choice for the production of nitrile gloves. Currently, with the continuous development of the economy, various industries are placing increasingly high demands on the wear resistance of nitrile gloves.

[0003] Relevant studies have found that the bound nitrile content in carboxyl nitrile latex has a great influence on the wear resistance of nitrile gloves. Through testing, it was found that the current bound nitrile content of carboxyl nitrile latex is still relatively low, which is difficult to meet the needs of consumers, resulting in poor wear resistance of the nitrile gloves produced. Summary of the Invention

[0004] In order to increase the bound nitrile content of carboxyl nitrile latex, the present application provides a carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves and a preparation method thereof.

[0005] In the first aspect, the present application provides a carboxylated nitrile latex for high-strength and wear-resistant nitrile gloves, which adopts the following technical solution:

[0006] A carboxylated nitrile latex for high-strength, wear-resistant nitrile gloves comprises a component A, a component B, and a component C, wherein the mass ratio of component A to component B is 1:(2-4); based on the total weight of component A, component A comprises the following raw materials in parts by weight: 140-145 parts of an emulsifier A, 140-160 parts of methacrylic acid, 10-20 parts of a molecular weight regulator, and 1300-1400 parts of acrylonitrile; based on the total weight of component B, component B comprises the following raw materials in parts by weight: 170-180 parts of an emulsifier B, 4.0-4.1 parts of an initiator, and 4600-4800 parts of deionized water; and component C comprises 170-180 parts of emulsifier C in parts by weight, based on the total weight of component B.

[0007] By adopting the above-mentioned technical scheme, the emulsifier A in component A is a nonionic surfactant, which can reduce critical surface tension, so that methacrylic acid and acrylonitrile are dispersed into droplets, and coated on the droplet surface, stop methacrylic acid and acrylonitrile to condense. Acrylonitrile can improve the mechanical properties and oil resistance of carboxyl nitrile latex. Molecular weight regulator can effectively regulate the distribution of acrylic resin molecular weight, controls the viscosity of carboxyl nitrile latex, and is beneficial to methacrylic acid and acrylonitrile polymerization. The initiator in component B can cause methacrylic acid and acrylonitrile copolymerization, and emulsifier B and initiator are added to deionized water and mixed, which can improve the chemical stability and mechanical stability of initiator. The adding of emulsifier C can improve the stability of carboxyl nitrile latex.

[0008] Preferably, the emulsifier A is a mixture of sodium dodecylbenzenesulfonate and sodium dodecyl diphenyl ether disulfonate; the mass ratio of sodium dodecyl diphenyl ether disulfonate to sodium dodecylbenzenesulfonate is 1:(1-1.1); and the emulsifier B and emulsifier C are both sodium dodecylbenzenesulfonate.

[0009] By adopting the above technical solution, emulsifier A is a mixture of sodium dodecylbenzene sulfonate and sodium dodecyl diphenyl oxide disulfonate, wherein sodium dodecylbenzene sulfonate is an anionic surfactant with good surface activity and strong hydrophilicity, thereby improving the stability of the copolymerization system. Sodium dodecyl diphenyl oxide disulfonate is an anionic surfactant with high dispersibility, which causes methacrylic acid, acrylonitrile and butadiene to form small droplets, prevents monomer aggregation, and improves the stability of the reaction solution. Both have hydrophilic groups. The addition of sodium dodecyl diphenyl oxide disulfonate can improve the stability of sodium dodecylbenzene sulfonate, neither affecting the polymerization reaction nor further improving the emulsification effect of the emulsion.

[0010] Preferably, the carboxyl nitrile latex raw material for high-strength and wear-resistant nitrile gloves further comprises 10-20 parts of distearyl pentaerythritol diphosphite.

[0011] By adopting the above technical solution, carboxylated nitrile latex will be affected by heat and oxygen during production, and latex will precipitate during storage. Distearyl pentaerythritol diphosphite is added as an antioxidant to prevent latex precipitation and improve the storage stability of carboxylated nitrile latex.

[0012] Preferably, the carboxyl nitrile latex raw material for high-strength and wear-resistant nitrile gloves further comprises 0.5-1 parts of a polymer stabilizer.

[0013] By adopting the above technical solution and adding a polymerization stabilizer, the polymer can be prevented from being cross-linked or degraded during the polymerization process, thereby further improving the stability of the reaction solution and the effect of the copolymerization reaction, thereby improving the wear resistance of the carboxyl nitrile latex.

[0014] The polymerization stabilizer is a mixture of 2,6-di-tert-butyl-p-cresol and diethylhydroxylamine; the mass ratio of the diethylhydroxylamine to the 2,6-di-tert-butyl-p-cresol is 1:(1-1.3).

[0015] By adopting the above technical solution, a mixture of 2,6-di-tert-butyl-p-cresol and diethylhydroxylamine is selected as a polymerization stabilizer, which has a good inhibition effect. In addition, 2,6-di-tert-butyl-p-cresol can effectively avoid the disadvantage that the inhibition effect of diethylhydroxylamine decreases with increasing temperature, and effectively improve the high-temperature stability of diethylhydroxylamine.

[0016] Preferably, the molecular weight regulator is one of n-dodecyl mercaptan and tert-dodecyl mercaptan.

[0017] The molecular weight regulator of the present application is selected from n-dodecyl mercaptan or tert-dodecyl mercaptan, and the carboxyl nitrile latex has high wear resistance.

[0018] Preferably, the initiator is one of ammonium persulfate, sodium persulfate, diisopropylbenzene hydroperoxide, isopropyl tert-butyl peroxide or isopropyl n-butyl peroxide.

[0019] When the initiator of the present application is selected from ammonium persulfate, sodium persulfate, diisopropyl hydroperoxide, isopropyl tert-butyl peroxide or isopropyl n-butyl peroxide, the carboxyl nitrile latex has high wear resistance.

[0020] In a second aspect, the present application provides a method for preparing any of the above-mentioned carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves.

[0021] A method for preparing carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves comprises the following steps:

[0022] S1. Mix emulsifier A, methacrylic acid, a molecular weight regulator, and acrylonitrile, stir evenly, and heat to 38-42° C. to obtain component A;

[0023] S2. Mix emulsifier B, initiator and deionized water, stir evenly, and heat to 43-47° C. to obtain component B;

[0024] S3. Replace with nitrogen 4 times, place component B under vacuum conditions, maintain -0.097 ~ -0.099 MPa, add component A dropwise for 10-20 minutes, then add butadiene dropwise for 120-150 minutes. When the conversion rate reaches 70-75%, add emulsifier C, react at 43-47 ° C for 14-16 hours, adjust the pH to 7.5-9, and obtain carboxylated nitrile latex.

[0025] By adopting the above technical solution, emulsifier A, methacrylic acid, a molecular weight regulator, and acrylonitrile are uniformly mixed and heated to 38-42°C to initiate the polymerization reaction. The molecular weight regulator effectively adjusts the molecular weight distribution of the acrylic resin and controls the viscosity of the carboxylated nitrile latex, facilitating the polymerization of methacrylic acid and acrylonitrile. Emulsifier A reduces the critical surface tension, dispersing methacrylic acid and acrylonitrile into small droplets. The emulsifier coats the surface of the droplets, preventing the methacrylic acid and acrylonitrile from agglomerating. Acrylonitrile improves the wear resistance and oil resistance of the carboxylated nitrile latex.

[0026] The initiator in component B initiates the copolymerization reaction of methacrylic acid and acrylonitrile. The chemical stability and mechanical stability of the initiator can be improved by adding the emulsifier B and the initiator into deionized water and mixing them.

[0027] The atmosphere is then replaced with nitrogen four times, and component A is added dropwise under vacuum, followed by butadiene. Emulsifier C is added for reaction, and the pH value is adjusted to improve the stability of the carboxylated nitrile latex. Butadiene can improve the softness and elasticity of the carboxylated nitrile latex.

[0028] Preferably, a method for preparing carboxyl nitrile latex for high-strength wear-resistant nitrile gloves comprises the following steps:

[0029] S1. Mix emulsifier A, methacrylic acid, a molecular weight regulator, and acrylonitrile, stir evenly, and heat to 38-42° C. to obtain component A;

[0030] S2. Mix emulsifier B, initiator and deionized water, stir evenly, and heat to 43-47° C. to obtain component B;

[0031] S3. Replace with nitrogen 4 times, place component B under vacuum conditions, maintain -0.097 ~ -0.099 MPa, add component A dropwise for 10-20 minutes, add butadiene dropwise for 120-150 minutes, and when the conversion rate reaches 70-75%, add emulsifier C, react at 43 ~ 47 ° C for 14 ~ 16 hours, add distearyl pentaerythritol diphosphite, adjust the pH to 7.5-9, and obtain carboxylated nitrile latex.

[0032] Preferably, a method for preparing carboxyl nitrile latex for high-strength wear-resistant nitrile gloves comprises the following steps:

[0033] S1. Mix emulsifier A, methacrylic acid, a molecular weight regulator, and acrylonitrile, stir evenly, and heat to 38-42° C. to obtain component A;

[0034] S2. Mix emulsifier B, initiator and deionized water, stir evenly, and heat to 43-47° C. to obtain component B;

[0035] S3. Replace with nitrogen 4 times, place component B under vacuum conditions, maintain -0.097 ~ -0.099 MPa, add component A dropwise for 10-20 minutes, then add butadiene dropwise for 120-150 minutes. When the conversion rate reaches 70-75%, add emulsifier C, react at 43 ~ 47 ° C for 14 ~ 16 hours, add a polymerization stabilizer, adjust the pH to 7.5-9, and obtain carboxylated nitrile latex.

[0036] In summary, this application includes at least one of the following beneficial technical effects:

[0037] (1) The present application adjusts the mass ratio of sodium dodecyl diphenyl ether disulfonic acid salt to sodium dodecylbenzene sulfonate in emulsifier A so that the solid content and bound nitrile content of the carboxylated nitrile latex are 52.81% and 40.5%, respectively, and the mechanical stability and chemical stability are 0.005% and 1.9%, respectively, thereby improving the bound nitrile content and stability of the carboxylated nitrile latex.

[0038] (2) The present application adds distearyl pentaerythritol diphosphite to the carboxylated nitrile latex raw material, so that the solid content and bound nitrile content of the carboxylated nitrile latex are 52.85% and 40.7% respectively, and the mechanical stability and chemical stability are 0.004% and 1.8% respectively, thereby further improving the bound nitrile content and stability of the carboxylated nitrile latex.

[0039] (3) The present application adds distearyl pentaerythritol diphosphite to the carboxylated nitrile latex raw material, and then adds diethylhydroxylamine and 2,6-di-tert-butyl-p-cresol, so that the solid content and bound nitrile content of the carboxylated nitrile latex are 53.01% and 42.0% respectively, and the mechanical stability and chemical stability are 0.001% and 1.3% respectively, thereby improving the bound nitrile content and stability of the carboxylated nitrile latex, and the tear resistance and abrasion resistance of the nitrile gloves impregnated with the carboxylated nitrile latex reach level 5 and level 4, thereby improving the abrasion resistance and strength of the nitrile gloves. DETAILED DESCRIPTION

[0040] The present application is further described in detail below with reference to specific embodiments.

[0041] The following raw materials in this application are all commercially available products. They are provided to ensure that the raw materials in this application are fully disclosed and should not be construed as limiting the sources of the raw materials. Specifically, they are: sodium dodecylbenzenesulfonate, active substance content ≥60%; sodium dodecyl diphenyl ether disulfonic acid salt, active substance content ≥40%; methacrylic acid, active substance content 99%; molecular weight regulator, selected as dodecyl mercaptan; acrylonitrile, active substance content 99.5%; sodium dodecylbenzenesulfonate, active substance content 99%; initiator, selected as ammonium persulfate; diethylhydroxylamine, active substance content 99%; 2,6-di-tert-butyl-p-cresol, model DW3432; sodium nitrite, active substance content 99%; distearyl pentaerythritol diphosphite, active substance content 99%.

[0042] The following is an example of the preparation of emulsifier A

[0043] Preparation Example 1

[0044] The emulsifier A of Preparation Example 1 was prepared by the following steps: sodium dodecylbenzenesulfonate and sodium dodecyl diphenyl ether disulfonate were mixed and stirred uniformly to obtain emulsifier A. The specific dosage is shown in Table 1.

[0045] Preparation Example 2-4

[0046] The preparation method of emulsifier A of Preparation Example 2-4 is the same as that of Preparation Example 1, except that the dosages of sodium dodecylbenzenesulfonate and sodium dodecyl diphenyl ether disulfonate are different, as shown in Table 1 for details.

[0047] Table 1 The dosage of each raw material of emulsifier A

[0048] raw material Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Sodium dodecylbenzenesulfonate 71.5 69.8 68.1 75.2 Dodecyl diphenyl ether disulfonic acid sodium salt 71.5 73.2 74.9 67.8

[0049] Example 1

[0050] The high-strength, wear-resistant carboxyl nitrile latex for nitrile gloves of Example 1 is prepared by the following preparation method:

[0051] S1, 143kg emulsifier A, 150kg methacrylic acid, 15kg molecular weight regulator (tert-dodecyl mercaptan) and 1350kg acrylonitrile were mixed, stirred evenly, and heated to 40°C to obtain component A;

[0052] S2. Mix 175 kg of emulsifier, 4.05 kg of initiator (ammonium persulfate) and 4700 kg of deionized water, stir evenly, and heat to 45° C. to obtain component B;

[0053] S3. Replace the mixture with nitrogen four times, place component B under vacuum, maintain -0.098 MPa, add component A dropwise for 15 minutes, then add butadiene dropwise for 130 minutes. When the conversion rate reaches 75%, add 175 kg of emulsifier C, react at 45° C. for 15 hours, and adjust the pH to 8 to obtain a carboxylated butadiene nitrile latex. Wherein, emulsifier A, emulsifier B, and emulsifier C are all sodium dodecylbenzenesulfonate.

[0054] Examples 2-5

[0055] The preparation method of the carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves of Examples 2-5 is the same as that of Example 1, except that emulsifier A is replaced by emulsifier A prepared in Preparation Examples 1-4, and the types and dosages of the other raw materials are the same as those in Example 1.

[0056] Example 6

[0057] The high-strength, wear-resistant carboxyl nitrile latex for nitrile gloves of Example 6 is prepared by the following preparation method:

[0058] S1. Mix 143 kg of emulsifier A prepared in Preparation Example 2, 150 kg of methacrylic acid, 15 kg of a molecular weight regulator (tert-dodecyl mercaptan), and 1350 kg of acrylonitrile, stir evenly, and heat to 40° C. to obtain component A;

[0059] S2, same as Example 1;

[0060] S3. Replace the mixture with nitrogen four times, place component B under vacuum, maintain -0.098 MPa, add component A dropwise for 15 minutes, then add butadiene dropwise for 130 minutes. When the conversion rate reaches 75%, add 175 kg of emulsifier C, react at 45° C. for 15 hours, add 15 kg of distearyl pentaerythritol diphosphite, and adjust the pH to 8 to obtain a carboxylated nitrile latex. Wherein, emulsifier B and emulsifier C are both sodium dodecylbenzenesulfonate.

[0061] Example 7

[0062] The high-strength, wear-resistant carboxyl nitrile latex for nitrile gloves of Example 7 is prepared by the following preparation method:

[0063] S1, same as Example 5;

[0064] S2, same as Example 1;

[0065] S3, replace with nitrogen 4 times, place component B under vacuum condition, maintain -0.098mpa, add component A dropwise, add butadiene dropwise for 15min, when conversion rate reaches 75%, add 175kg emulsifier C, react under 45℃ condition for 15h, add 0.8kg polymerization stabilizer, adjust pH to 8, and obtain carboxylated butadiene latex. Wherein, emulsifier B and emulsifier C are both sodium dodecylbenzene sulfonate, and polymerization stabilizer is sodium nitrite.

[0066] Examples 8-11

[0067] The preparation method of the carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves in Examples 8-11 is the same as that in Example 7, except that the polymerization stabilizer is the polymerization stabilizer prepared in Preparation Examples 5-8, and the types and dosages of the other raw materials are the same as those in Example 1.

[0068] Example 12

[0069] The preparation method of the carboxylated nitrile latex for high-strength and wear-resistant nitrile gloves in Example 12 is the same as that in Example 9, except that in step S3, after reacting at 45° C. for 15 hours, 15 kg of distearyl pentaerythritol diphosphite is added, and the types and amounts of other raw materials are the same as those in Example 9.

[0070] Comparative Example 1

[0071] The preparation method of the carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves in Comparative Example 1 is the same as that in Example 1, except that no emulsifier B is added in step S2, and the types and amounts of other raw materials are the same as those in Example 1.

[0072] Comparative Example 2

[0073] The preparation method of the carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves in Comparative Example 2 is the same as that in Example 1, except that no emulsifier C is added in step S3, and the types and amounts of other raw materials are the same as those in Example 1.

[0074] Comparative Example 3

[0075] The preparation method of the carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves in Comparative Example 3 is the same as that in Example 1, except that nitrogen is used for replacement three times in step S3, and the types and amounts of other raw materials are the same as those in Example 1.

[0076] Performance testing

[0077] The following testing standards or methods were used to test the properties of the carboxyl nitrile latex obtained in different Examples 1-12 and Comparative Examples 1-3. The test results are shown in Table 2.

[0078] Solid content: The solid content of carboxyl fixative latex was determined according to the method of GB2958-82.

[0079] Bound nitrile content: The bound nitrile content of carboxylated nitrile latex was determined according to the method of SH / T 1503-2014.

[0080] Mechanical stability: The mechanical stability of carboxyl nitrile latex was tested using a latex mechanical stability tester. The specific test method is as follows: 50 g of carboxyl nitrile latex was weighed, rotated at a speed of 14,000 r / min for 30 minutes, filtered, and the flocculant content was determined.

[0081] Chemical stability: The stability of carboxylated nitrile latex to calcium ions is characterized by the following test method: 5 g of calcium chloride solution is added to 50 g of carboxylated nitrile latex, shaken for 2 hours, filtered, and the flocculent content is determined.

[0082] Table 2 Performance test results of different carboxyl nitrile latex

[0083]

[0084] The test results in Table 2 show that the solid content and bound nitrile content of the carboxylated nitrile latex obtained in the present application are respectively 53.01% and 42%, which improve the solid content and bound nitrile content of the carboxylated nitrile latex, and the mechanical stability and chemical stability are as low as 0.001% and 1.5%, which improves the stability of the carboxylated nitrile latex.

[0085] Combining the performance test data of the carboxylated nitrile latexes of Examples 1 and 2-5, it can be seen that the solid content and bound nitrile content of the carboxylated nitrile latex of Example 3 are 52.81% and 40.5%, respectively, both higher than those of Examples 1-2 and 4-5. The mechanical stability and chemical stability are 0.005% and 1.9%, respectively, both lower than those of Examples 1-2 and 4-5. This indicates that when the emulsifier A in the carboxylated nitrile latex is a mixture of sodium dodecylbenzenesulfonate and sodium dodecyldiphenylether disulfonate, with a mass ratio of sodium dodecyldiphenylether disulfonate to sodium dodecylbenzenesulfonate of 1:1.05, the bound nitrile content and stability of the carboxylated nitrile latex are increased. This may be due to the fact that sodium dodecylbenzenesulfonate is an anionic surfactant with good surface activity and strong hydrophilicity, which improves the stability of the copolymer system. Sodium dodecyldiphenylether disulfonate has high dispersibility, causing methacrylic acid, acrylonitrile, and butadiene to form small droplets, preventing monomer aggregation and improving the stability of the reaction solution.

[0086] As can be known, the solid content of embodiment 6 carboxyl acrylonitrile latex and in conjunction with nitrile content are respectively 52.85% and 40.7% in conjunction with embodiment 3, all higher than embodiment 3, mechanical stability and chemical stability are respectively 0.004% and 1.8%, all lower than embodiment 3, show and add distearyl pentaerythritol diphosphite in the carboxyl acrylonitrile latex raw material, can improve in conjunction with nitrile content and the stability of carboxyl acrylonitrile latex.May with the influence of carboxyl acrylonitrile latex can be heated and oxygen in production, have latex to separate out in the storage process, distearyl pentaerythritol diphosphite adds as antioxidant, can prevent latex from separating out, and improving the storage stability of carboxyl acrylonitrile latex is relevant.

[0087] In Examples 7-11, the solid content and bound nitrile content of the carboxylated nitrile latex of Example 9 were 53.1% and 41.7%, respectively, both higher than those of Examples 7-8 and Examples 10-11. The mechanical stability and chemical stability were 0.003% and 1.5%, respectively, both lower than those of Examples 7-8 and Examples 10-11. This indicates that the addition of a polymerization stabilizer to the carboxylated nitrile latex raw material, with a mass ratio of diethylhydroxylamine to 2,6-di-tert-butyl-p-cresol of 1:1.2, can increase the bound nitrile content and stability of the carboxylated nitrile latex. This may be due to the excellent polymerization inhibition effect of the mixture of 2,6-di-tert-butyl-p-cresol and diethylhydroxylamine selected as the polymerization stabilizer. Furthermore, 2,6-di-tert-butyl-p-cresol effectively avoids the decrease in the polymerization inhibition effect of diethylhydroxylamine with increasing temperature, effectively improving the high-temperature stability of diethylhydroxylamine.

[0088] Combining the performance test data of the carboxyl nitrile latex of Example 9 and Example 12, it can be seen that the solid content and bound nitrile content of the carboxyl nitrile latex of Example 12 are 53.01% and 42.0%, respectively, both higher than Example 9, and the mechanical stability and chemical stability are 0.001% and 1.3%, respectively, both lower than Example 9, indicating that the addition of a composite polymer stabilizer on the basis of adding distearyl pentaerythritol diphosphite to the carboxyl nitrile latex raw material can further improve the bound nitrile content and stability of the carboxyl nitrile latex.

[0089] In addition, based on the various indicator data of the carboxyl nitrile latex of Comparative Examples 1-3 and Example 1, it was found that the addition of emulsifier B and emulsifier C to the carboxyl latex raw material and replacement with nitrogen three times in step S3 can increase the bound nitrile content of the carboxyl nitrile latex to varying degrees.

[0090] The following are the applications of carboxylated nitrile latex

[0091] Application Example 1

[0092] Application Example 1 The application method of the carboxyl nitrile latex is as follows: nitrile gloves that have not been dipped are dipped into the carboxyl nitrile latex of Example 1, dipped for 2 hours, taken out, and dried to obtain nitrile gloves.

[0093] Application Example 2

[0094] The application method of the carboxylated nitrile latex in Application Example 2 is different from that in Application Example 1 in that the carboxylated nitrile latex obtained in Example 12 is used.

[0095] Application Comparative Examples 1-3

[0096] The application method of the carboxyl nitrile latex of Comparative Examples 1-3 is different from that of Application Example 1 in that the carboxyl nitrile latex obtained in Comparative Examples 1-3 is used.

[0097] Performance testing

[0098] The abrasion resistance and tear resistance of nitrile gloves were tested according to standard EN388. The specific test results are shown in Table 3.

[0099] Table 3 Performance test results of nitrile gloves dipped in different carboxyl nitrile latex

[0100]

[0101] The test results in Table 3 show that the nitrile gloves impregnated with the carboxyl nitrile latex obtained in this application have high tear resistance and abrasion resistance, reaching levels 5 and 4 respectively, thereby improving the abrasion resistance and strength of the nitrile gloves.

[0102] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves, characterized in that: The invention comprises component A, component B and component C, wherein the mass ratio of component A to component B is 1:(2-4); based on the total weight of component A, component A comprises the following raw materials in parts by weight: 140-145 parts of emulsifier A, 140-160 parts of methacrylic acid, 10-20 parts of molecular weight regulator, and 1300-1400 parts of acrylonitrile; based on the total weight of component B, component B comprises the following raw materials in parts by weight: 170-180 parts of emulsifier B, 4.0-4.1 parts of initiator, and 4600-4800 parts of deionized water; and based on the total weight of component B, component C comprises 170-180 parts of emulsifier C. The emulsifier A is a mixture of sodium dodecylbenzenesulfonate and sodium dodecyl diphenyl ether disulfonate; the mass ratio of sodium dodecyl diphenyl ether disulfonate to sodium dodecylbenzenesulfonate is 1:(1-1.1); the emulsifier B and emulsifier C are both sodium dodecylbenzenesulfonate; The carboxyl nitrile latex raw material for high-strength and wear-resistant nitrile gloves also includes 10-20 parts of distearyl pentaerythritol diphosphite; the carboxyl nitrile latex raw material for high-strength and wear-resistant nitrile gloves also includes 0.5-1 parts of a polymerization stabilizer; the polymerization stabilizer is sodium nitrite.

2. The carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves according to claim 1, characterized in that: The molecular weight regulator is one of n-dodecyl mercaptan and tert-dodecyl mercaptan.

3. The carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves according to claim 1, characterized in that: The initiator is one of ammonium persulfate, sodium persulfate, diisopropylbenzene hydroperoxide, isopropyl tert-butyl peroxide or isopropyl n-butyl peroxide.

4. A method for preparing the carboxyl nitrile latex for high-strength and wear-resistant nitrile gloves according to any one of claims 1 to 3, characterized in that: It includes the following steps: S1. Mix emulsifier A, methacrylic acid, a molecular weight regulator, and acrylonitrile, stir evenly, and heat to 38-42° C. to obtain component A; S2. Mix emulsifier B, initiator and deionized water, stir evenly, and heat to 43-47° C. to obtain component B; S3. Replace with nitrogen 4 times, place component B under vacuum conditions, maintain -0.097 to -0.099 MPa, add component A dropwise for 10-20 minutes, then add butadiene dropwise for 120 to 150 minutes. When the conversion rate reaches 70-75%, add emulsifier C, react at 43 to 47°C for 14 to 16 hours, add distearyl pentaerythritol diphosphite and a polymerization stabilizer, adjust the pH to 7.5-9, and obtain carboxylated butadiene latex.

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