Flame-retardant hot-line work glove and preparation method thereof

Abstract

The invention discloses a flame-retardant hot-line work glove and a preparation method thereof, and belongs to the technical field of high polymer materials, and the flame-retardant hot-line work glove comprises the following components: natural latex, hydrogenated epoxidized natural rubber, a hyperbranched polymer, antimony trioxide, aramid fiber, a vulcanizing agent, a vulcanization accelerator, an anti-aging agent, zinc oxide and a stabilizer. Polyoxyethylene castor oil and a softening agent; the natural latex is secondarily centrifuged natural latex. The glove has excellent flame retardant property and insulating property, is excellent in safety and has a wide application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a flame-retardant live-working glove and a preparation method thereof. Background Art

[0002] With the development of science and technology and society, various industries are increasingly dependent on electricity. Power outages during circuit maintenance and inspection will cause significant economic losses. Therefore, live working has become a common maintenance requirement in modern times. And the protection of the body during live working has become a top priority. Because the working environment of electricians is relatively dangerous, protective gloves have become an important and necessary labor protection product for maintenance electricians, which protects hands and the human body from electric shock. Today, as a necessary protective product for electrical work, the demand for insulating gloves is increasing, driving the rapid development of the labor protection product market.

[0003] Insulating gloves for live working are an important part of insulation protection in personal protective equipment. With the development of the power industry and the promotion of live working technology, more stringent requirements have been put forward for the safety of insulating gloves for live working. Especially in the process of using electricity, there are fires caused by excessive current and aging of cables. When electricians wear live working gloves for live working, there may be a possibility of excessive local current or contact with high-temperature objects, causing the gloves to burn, seriously threatening the life safety of electricians. Therefore, the flame retardant performance of insulating gloves is also an important indicator proposed by customers.

[0004] At present, insulating gloves for live working are usually selected according to the electrical performance requirements of different working environments. Their main materials are usually natural rubber or special rubbers such as styrene-butadiene rubber, butadiene rubber, butyl rubber, ethylene-propylene rubber, silicone rubber, etc. Natural rubber is widely used in various fields due to its excellent fatigue performance, high elasticity, corrosion resistance and good processing performance. However, since natural rubber is easy to burn, its application range is also limited to a certain extent. Therefore, natural rubber needs to be flame-retardant modified.

[0005] In view of this, this application is filed. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a flame retardant live working glove and a preparation method thereof. The glove has excellent flame retardant and insulating properties, excellent safety, and broad application prospects.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] A flame-retardant live-work glove comprising the following components in parts by weight: 100 parts of natural latex, 8-15 parts of hydrogenated epoxidized natural rubber, 2-5 parts of hyperbranched polymer, 3-6 parts of antimony trioxide, 1-3 parts of aramid fiber, 1-4 parts of vulcanizing agent, 0.5-2 parts of vulcanization accelerator, 0.8-2 parts of antioxidant, 0.2-2 parts of zinc oxide, 0.1-1.5 parts of stabilizer, 0.1-0.25 parts of polyoxyethylene castor oil, and 1-3 parts of softener;

[0009] The natural latex is secondary centrifuged natural latex.

[0010] The present invention combines the above raw materials according to specific weight parts, and through the mutual cooperation of each component, obtains gloves with excellent flame retardant performance and insulating performance. The gloves have excellent safety and broad application prospects.

[0011] The present invention adopts a secondary centrifugal natural latex system. The secondary centrifugal natural latex refers to concentrated natural latex obtained by two centrifugal concentration processes. The solid content of the secondary centrifugal natural latex is ≥60%, and the water-soluble protein content is ≤90μg / g, and the latex has relatively better insulation performance.

[0012] In the present invention, antimony trioxide is used as a flame retardant, and aramid fiber is used in combination to effectively improve the flame retardancy and insulation properties of the gloves. At the same time, hyperbranched polymer and hydrogenated epoxidized natural rubber are added to the natural latex system, which not only promotes the good dispersion of antimony trioxide and aramid fiber in the natural latex system, but also significantly improves the insulation and puncture resistance of the gloves.

[0013] Preferably, the hydrogenated epoxidized natural rubber is prepared by hydrogenating the epoxidized natural rubber in an autoclave under the catalysis of palladium acetate.

[0014] In the present invention, the epoxidized natural rubber is prepared from a specific epoxidized natural rubber through a specific catalytic reaction. The epoxidized natural rubber has an epoxy bond and has excellent polarity and chemical activity. In the gloves of the natural latex system of the present invention, the epoxy bond can be used as a bridge to combine the epoxy group in the hydrogenated epoxidized natural rubber with the polar site of the hyperbranched polymer. At the same time, the main chain of the hydrogenated epoxidized natural rubber has structural similarities with the natural latex. This "bridge effect" can enhance the molecular interaction between the natural latex and the hyperbranched polymer and improve the compatibility of the two. It can also improve the problem of uneven interface or insufficient bonding force caused by the difference in polarity between components through chemical bonds or hydrogen bonds, improve the uniformity of the mixed system, form a tightly cross-linked network, thereby inhibiting the phase separation that may exist in the gloves of the natural latex system, and then improve the comprehensive performance of the gloves.

[0015] However, only epoxidized natural rubber with a high degree of epoxidation can well improve the compatibility and interfacial effect of natural latex and hyperbranched polymer, but when the epoxidation degree is too high, the epoxy bond of the epoxidized natural rubber, as a three-membered ring structure, has a large internal stress, and is prone to ring opening or fracture when subjected to mechanical stress (such as puncture); and the thermal stability of the epoxy group is insufficient, and a ring opening reaction is prone to occur under high temperature conditions, which will lead to the destruction of the molecular chain, thereby reducing the flame retardant properties of the material. The present invention finds that by hydrogenating the epoxidized natural rubber and reducing its unsaturated bonds, the heat resistance of the material can be improved, and the risk of glove puncture or flame retardant properties caused by more epoxy bonds in the epoxidized natural rubber can be alleviated. However, conventional hydrogenation reactions may be carried out on two reactive groups, the double bond and the epoxy group in the epoxidized natural rubber. By selecting palladium acetate as a catalyst, hydrogenation can be selectively carried out at the double bond position without changing the epoxidation degree of the epoxidized natural rubber.

[0016] Preferably, the degree of hydrogenation of the hydrogenated epoxidized natural rubber is 20 to 30%.

[0017] When the degree of hydrogenation is between 20% and 30%, the heat resistance of the hydrogenated epoxidized natural rubber is good, and the flexibility and hardness are balanced. When the degree of hydrogenation is too high, the compatibility of the hydrogenated epoxidized natural rubber in the glove system of the present invention may be deteriorated, and the mechanical properties may change too much, affecting the comprehensive performance of the gloves.

[0018] Preferably, the epoxidation degree of the epoxidized natural rubber is 50-65%.

[0019] The epoxidation degree of the epoxidized natural rubber is 50-65%. After the hydrogenation reaction using palladium acetate as a catalyst, the epoxidation degree of the hydrogenated epoxidized natural rubber is also basically 50-65%.

[0020] Specifically, hydrogenated epoxidized natural rubber can be prepared by the following method:

[0021] The epoxidized natural rubber is dissolved in a mixture of chloroform and acetone in a volume ratio of 1:1, palladium acetate is added, and hydrogen is introduced into a high-pressure reactor for hydrogenation reaction. The product after the reaction is washed to obtain hydrogenated epoxidized natural rubber.

[0022] The temperature of the hydrogenation reaction may be 60° C., and the reaction pressure may be 2.7 MPa. The extent of the hydrogenation reaction, that is, the hydrogenation degree of the hydrogenated epoxidized natural rubber, may be controlled by adjusting the reaction time.

[0023] The degree of hydrogenation of hydrogenated epoxidized natural rubber can be detected and calculated by infrared spectroscopy and nuclear magnetic resonance spectroscopy.

[0024] In the present invention, the hyperbranched polymer is used to disperse antimony trioxide and aramid fiber, thereby further improving the flame retardant property of the gloves; on the other hand, the hyperbranched polymer has a special molecular structure, thereby improving the puncture resistance of the gloves.

[0025] In the present invention, antimony trioxide and aramid fiber are firstly blended with a hyperbranched polymer under ultrasonic conditions so that the surfaces of antimony trioxide and aramid fiber are coated with a certain amount of hyperbranched polymer, and then added into a natural latex system containing hydrogenated epoxidized natural rubber, thereby reducing the agglomeration of fillers and achieving good dispersion of the fillers in the natural rubber system.

[0026] Due to the presence of the cross-linked network, the molecular chain mobility of the hyperbranched polymer is lower when heated, which can effectively inhibit the thermal decomposition and flame propagation of the material, making the transfer of heat energy more difficult, thereby improving the thermal stability and flame retardancy of the material, and helping to slow down the thermal degradation of the gloves.

[0027] As a preferred embodiment of the present invention, the hyperbranched polymer is at least one selected from the group consisting of hydroxyl-terminated hyperbranched polyester, hydroxyl-terminated hyperbranched polyamide, carboxyl-terminated hyperbranched polyester, and amino-terminated hyperbranched polyamide.

[0028] As a preferred embodiment of the present invention, the hyperbranched polymer is an amino-terminated hyperbranched polyamide.

[0029] The amino groups in the hyperbranched polymers containing terminal amino groups have strong chemical reactivity and can undergo nucleophilic ring-opening reactions with the epoxy groups in hydrogenated epoxidized natural rubber. Although carboxyl groups can also react with epoxy groups, the resulting ester bonds are prone to breakage at high temperatures and have insufficient thermal stability. The reactivity of hydroxyl groups is slightly lower than that of amino groups, resulting in weaker crosslinking density and uniformity. Therefore, the chemical bonds generated by the reaction of terminal amino hyperbranched polyamides have higher thermal stability and mechanical strength than crosslinks formed by other groups.

[0030] In addition, the reactivity of the amino group will increase the cross-linking density of the material, forming a denser and more uniform network from the microstructural point of view. This reinforcement effect directly improves the puncture resistance, especially the puncture resistance in high temperature environments.

[0031] As a preferred embodiment of the present invention, the number of terminal amino groups of the amino-terminated hyperbranched polyamide is 8 to 14 mol / mol.

[0032] The polarity of amino groups is relatively high, and the residual activity may affect the insulation performance. Therefore, it is necessary to control the number of terminal amino groups of the amino-terminated hyperbranched polyamide within an appropriate range so that the gloves can have excellent insulation performance, flame retardancy, and puncture resistance.

[0033] As a preferred embodiment of the present invention, the molecular weight of the amino-terminated hyperbranched polyamide is 800 to 1600 g / mol.

[0034] The molecular weight of amino-terminated hyperbranched polyamide affects its viscosity and fluidity, and further affects the dispersion degree of antimony trioxide and aramid fiber.

[0035] In the present invention, the hyperbranched polymer can be selected from commercially available products, or can be prepared by conventional preparation methods known to those skilled in the art.

[0036] As a preferred embodiment of the present invention, the weight ratio of the antimony trioxide to the aramid fiber is (1.5-3.5):1.

[0037] In the present invention, for the consideration of flame retardant properties, antimony trioxide with a smaller particle size is preferred, for example, antimony trioxide with an average particle size of 200 to 300 nm is preferred. However, inorganic fillers with too small a particle size are more likely to agglomerate and have poor dispersibility. The present invention finds that compounding a certain amount of fiber material in nano-scale inorganic particle powder helps to reduce the agglomeration of powder particles. Through the synergy of antimony trioxide and aramid fiber, the introduction of aramid fiber increases the rheological complexity of the mixing system. During the mixing process, aramid fiber forms a three-dimensional network structure, which plays a "bridging" role and helps to evenly disperse antimony trioxide into the matrix through shearing. In addition, aramid fiber has excellent insulation properties and mechanical properties. The addition of aramid fiber also helps the gloves have excellent insulation properties and puncture resistance in high temperature environments.

[0038] When the weight ratio of antimony trioxide to aramid fiber is within the above preferred range, the synergistic effect of the two is optimal, and the insulation performance, flame retardant performance and puncture resistance of the gloves are relatively better.

[0039] In consideration of the effect of promoting dispersion, the aramid fiber is preferably short-cut aramid fiber.

[0040] As a preferred embodiment of the present invention, the ratio of the weight of the hyperbranched polymer to the sum of the weight of antimony trioxide and the aramid fiber is (0.4-0.6):1.

[0041] As a preferred embodiment of the present invention, the stabilizer is peregrine O.

[0042] The described Peregal O is polyoxyethylene fatty alcohol ether, which is a nonionic surfactant. Optionally, the described Peregal O can be selected from Peregal O-15 and / or Peregal O-20.

[0043] As a preferred embodiment of the present invention, the vulcanizing agent is sulfur.

[0044] As a preferred embodiment of the present invention, the vulcanization accelerator is at least one of sodium dibutyl dithiocarbamate, dibenzothiazyl disulfide, zinc dimethyl dithiocarbamate, and zinc ethylphenyl dithiocarbamate.

[0045] As a preferred embodiment of the present invention, the antioxidant is at least one of antioxidant RD, antioxidant MB, and antioxidant 264.

[0046] As a preferred embodiment of the present invention, the softener is liquid paraffin.

[0047] The present invention also provides a method for preparing flame-retardant live-work gloves, comprising the following steps:

[0048] The hyperbranched polymer is mixed with antimony trioxide and aramid fiber, and then uniformly stirred by ultrasonication to obtain a mixture;

[0049] The vulcanizing agent, the vulcanization accelerator and the antioxidant are mixed and then ground to obtain a dispersion;

[0050] The mixture, dispersion, hydrogenated epoxidized natural rubber, zinc oxide, stabilizer, polyoxyethylene castor oil and softener are added to natural latex, mixed evenly, and pre-vulcanized to obtain vulcanized latex;

[0051] The glove mold is impregnated with a coagulant and dried, impregnated with latex, shaped, leached, and curled after cooling; impregnated with latex for a second time, dried, demoulded, and water-vulcanized; then washed with chlorine and dried again to obtain flame-retardant live-work gloves.

[0052] The beneficial effects of the present invention are:

[0053] The gloves described in the present invention adopt a secondary centrifugal natural latex system, combined with antimony trioxide and aramid fiber, as well as components such as hyperbranched polymer and hydrogenated epoxidized natural rubber. The flame-retardant live-work gloves have excellent flame-retardant properties, insulation properties and puncture resistance in high temperature environments, excellent safety, and broad application prospects. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0055] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0056] In the present application, there is no particular limitation on the specific dispersion and stirring treatment methods, as long as the corresponding uniform dispersion and uniform stirring are achieved.

[0057] The raw materials used in the embodiments and comparative examples are described as follows:

[0058] Natural latex: Secondary centrifugal natural latex was purchased from Shixiu New Material Technology (Zhejiang) Co., Ltd., with a solid content of 61% and a water-soluble protein content of 88μg / g.

[0059] Epoxidized natural rubber-1: Epoxidized natural rubber ENR-50, epoxidation degree 50%, purchased from Chinese Academy of Tropical Agricultural Sciences;

[0060] Epoxidized natural rubber-2: Epoxidized natural rubber ENR-65, epoxidation degree 65%, purchased from Shandong Changyao New Materials Co., Ltd.;

[0061] Epoxidized natural rubber-3: Epoxidized natural rubber ENR-75, epoxidation degree 75%, purchased from Shandong Changyao New Materials Co., Ltd.;

[0062] Epoxidized natural rubber-4: Epoxidized natural rubber ENR-25, with an epoxidation degree of 25%, was purchased from the Chinese Academy of Tropical Agricultural Sciences.

[0063] Hydrogenated epoxidized natural rubber is prepared by the following method:

[0064] The epoxidized natural rubber is dissolved in a mixture of chloroform and acetone in a volume ratio of 1:1, palladium acetate is added, and hydrogen is introduced into a high-pressure reactor for hydrogenation reaction. The temperature of the hydrogenation reaction is 60° C. and the reaction pressure is 2.7 MPa. The reaction time is adjusted to control the degree of the hydrogenation reaction. The product after the reaction is poured into methanol, and after washing and drying, the hydrogenated epoxidized natural rubber is obtained.

[0065] The hydrogenated epoxidized natural rubber-1 to the hydrogenated epoxidized natural rubber-4 are respectively made of the above-mentioned epoxidized natural rubber-1 to the epoxidized natural rubber-4 as raw materials, and the degree of hydrogenation is 30%.

[0066] Hydrogenated epoxidized natural rubber-5: epoxidized natural rubber-1 is used as a raw material, and the degree of hydrogenation is 20%.

[0067] Hydrogenated epoxidized natural rubber-6: epoxidized natural rubber-1 is used as a raw material, and the degree of hydrogenation is 5%.

[0068] Hydrogenated epoxidized natural rubber-7: epoxidized natural rubber-1 is used as a raw material, and the degree of hydrogenation is 45%.

[0069] Aramid fiber: powdered aramid fiber, ATT-KF-300F, Nanjing Tengyi New Material Technology Co., Ltd.

[0070] Antimony trioxide-1: average particle size 270 nm, purchased from Nangong Xindu Metal Materials Technology;

[0071] Antimony trioxide-2: average particle size 700 nm, purchased from Shanghai Puzhen Biological;

[0072] Antimony trioxide-3: average particle size 80 nm, purchased from Changde Chenzhou Antimony Products Co., Ltd.

[0073] Hyperbranched polymer-1: hydroxyl-terminated hyperbranched polyester, purchased from Wuhan Hyperbranched Resin Company, HyPer H202;

[0074] Hyperbranched polymer-2: hydroxyl-terminated hyperbranched polyamide, purchased from Wuhan Hyperbranched Resin Company, HyPerHPN202;

[0075] Hyperbranched polymer-3: carboxyl-terminated hyperbranched polyester, purchased from Wuhan Hyperbranched Resin Company, HyPer C102;

[0076] Hyperbranched polymer-4: amino-terminated hyperbranched polyamide, purchased from Wuhan Hyperbranched Resin Company, HyPer N101, with 3-4 amino groups / mol and molecular weight of 350-370 g / mol;

[0077] Hyperbranched polymer-5: amino-terminated hyperbranched polyamide, purchased from Wuhan Hyperbranched Resin Company, HyPer N102, with 8 to 9 amino groups / mol and a molecular weight of 820 to 900 g / mol;

[0078] Hyperbranched polymer-6, hyperbranched polymer-7: amino-terminated hyperbranched polyamide, homemade, prepared by: placing diethylenetriamine in a three-necked flask, adding a mixed solution of methyl acrylate and methanol dropwise under an ice-water bath and nitrogen protection, reacting at room temperature for 4 to 8 hours after the addition is complete to obtain a reaction monomer; then removing the methanol solvent, continuing to heat to 150°C and reacting under reduced pressure for 4 to 8 hours to obtain an amino-terminated hyperbranched polyamide; controlling the amount of raw materials added and the reaction time can adjust the number of amino groups and the molecular weight of the product;

[0079] Wherein: the number of terminal amino groups of hyperbranched polymer-6 is 10 to 12 / mol, and the molecular weight is 1180 to 1430 g / mol; the number of terminal amino groups of hyperbranched polymer-7 is 12 to 14 / mol, and the molecular weight is 1300 to 1600 g / mol;

[0080] Hyperbranched polymer-8: amino-terminated hyperbranched polyamide, purchased from Wuhan Hyperbranched Resin Company, HyPer N103, with 15-16 amino groups / mol and molecular weight of 2000-2200 g / mol.

[0081] Vulcanization accelerator: including zinc ethylphenyl dithiocarbamate, which is commonly available on the market.

[0082] Antioxidant: Antioxidant 264, commonly available in the market.

[0083] Vulcanizing agent: sulfur, commonly available in the market.

[0084] Stabilizer: Perchlorate O-15, commonly available in the market.

[0085] Softener: liquid paraffin, commonly available in the market.

[0086] Unless otherwise specified, the components, raw materials or instruments used in the embodiments and comparative examples of the present invention are all commercially available raw materials or instruments, and the components and raw materials used in each parallel experiment are all of the same kind.

[0087] The size and thickness specifications of the gloves prepared in the embodiments and comparative examples of the present invention are the same.

[0088] Example 1

[0089] A flame-retardant live-work glove comprises the following components in parts by weight: 100 parts of natural latex, 12 parts of hydrogenated epoxidized natural rubber (hydrogenated epoxidized natural rubber-1), 3 parts of hyperbranched polymer (hyperbranched polymer-6), 4 parts of antimony trioxide (antimony trioxide-1), 2.5 parts of aramid fiber, 2.5 parts of vulcanizing agent, 1.5 parts of vulcanization accelerator, 1.2 parts of antioxidant, 1 part of zinc oxide, 0.8 parts of stabilizer, 0.2 parts of polyoxyethylene castor oil, and 1.5 parts of softener.

[0090] The method for preparing the flame-retardant live-working gloves comprises the following steps:

[0091] (1) mixing the hyperbranched polymer with antimony trioxide and aramid fiber, and uniformly stirring the mixture by ultrasonic stirring at a temperature of 80° C., a time of 5 min, and a power of 500 W to obtain a mixture;

[0092] (2) mixing a vulcanizing agent, a vulcanization accelerator, and an antioxidant, and grinding the mixture to obtain a dispersion; adding the mixture, the dispersion, hydrogenated epoxidized natural rubber, zinc oxide, a stabilizer, polyoxyethylene castor oil, and a softener to natural rubber latex, mixing them evenly, and pre-vulcanizing at 70° C. for 30 minutes to obtain a vulcanized latex;

[0093] (3) dipping the glove mold into a coagulant and drying it, dipping it into latex, shaping it, leaching it, and curling it after cooling it; dipping it into latex for the second time, drying it, demoulding it, vulcanizing it in water at 80° C. for 50 min, and then washing it with chlorine and drying it to obtain a flame-retardant live-work glove with a glove length of 360 mm.

[0094] Example 2

[0095] The difference between Example 2 and Example 1 is that the hyperbranched polymer (hyperbranched polymer-6) is 4 parts, antimony trioxide (antimony trioxide-1) is 5 parts, and aramid fiber is 1.5 parts. The other parts are the same.

[0096] Example 3

[0097] The difference between Example 3 and Example 1 is that the amount of antimony trioxide (antimony trioxide-1) is 3.5 parts and the amount of aramid fiber is 3 parts. The other parts are the same.

[0098] Example 4

[0099] The difference between Example 4 and Example 1 is that antimony trioxide (antimony trioxide-1) is 5.5 parts and aramid fiber is 1 part. The other parts are the same.

[0100] Embodiments 5 to 10

[0101] The difference between Examples 5 to 10 and Example 1 is that the hydrogenated epoxidized natural rubber is replaced by hydrogenated epoxidized natural rubber-2 to hydrogenated epoxidized natural rubber-7 in equal weight, and the other parts are the same.

[0102] Embodiment 11, 12

[0103] The difference between Examples 11 and 12 and Example 1 is that antimony trioxide is replaced by antimony trioxide-2 and antimony trioxide-3 in equal weight, respectively, and the rest is the same as Example 1.

[0104] Examples 13 to 19

[0105] The difference between Examples 13 to 19 and Example 1 is that hyperbranched polymer-6 is replaced by hyperbranched polymer-7, hyperbranched polymer-5, hyperbranched polymer-4, hyperbranched polymer-8, hyperbranched polymer-1, hyperbranched polymer-2, and hyperbranched polymer-3 in equal weights, and the rest is the same as Example 1.

[0106] Embodiment 20

[0107] A flame-retardant live-work glove comprises the following components in parts by weight: 100 parts of natural latex, 18 parts of hydrogenated epoxidized natural rubber (hydrogenated epoxidized natural rubber-1), 2 parts of hyperbranched polymer (hyperbranched polymer-6), 2 parts of antimony trioxide (antimony trioxide-1), 2 parts of aramid fiber, 2.5 parts of vulcanizing agent, 2 parts of vulcanization accelerator, 0.8 parts of antioxidant, 1.5 parts of zinc oxide, 1.5 parts of stabilizer, 0.1 parts of polyoxyethylene castor oil, and 3 parts of softener.

[0108] Embodiment 21

[0109] The difference between Example 21 and Example 1 is that the hydrogenated epoxidized natural rubber-8 used in Comparative Example 4 is prepared by the following method:

[0110] The epoxidized natural rubber-1 is subjected to hydrogenation reaction by adding hydrogen gas under the catalytic condition of toluenesulfonyl hydrazide, and the hydrogenation reaction conditions are controlled so that the hydrogenation degree of the hydrogenated epoxidized natural rubber-8 is 30%.

[0111] The hydrogenated epoxidized natural rubber-8 of equal mass was used to replace the hydrogenated epoxidized natural rubber-1, and the other contents were the same as those in Example 1.

[0112] Comparative Example 1

[0113] The difference between Comparative Example 1 and Example 1 is that Comparative Example 1 uses epoxidized natural rubber of equal mass to replace the hydrogenated epoxidized natural rubber, and the other parts are the same.

[0114] Comparative Example 2

[0115] The difference between Comparative Example 2 and Example 1 is that the amount of aramid fiber added in Comparative Example 2 is 0, and the other aspects are the same.

[0116] Comparative Example 3

[0117] The difference between Comparative Example 3 and Example 1 is that the amount of aramid fiber added in Comparative Example 2 is 0, and the amount of antimony trioxide added is 6.5 parts, and the other contents are the same.

[0118] Comparative Example 4

[0119] Comparative Example 4 provides a flame retardant live-electric working glove, the components of which are the same as those of Example 1, except that the preparation method of the flame retardant live-electric working glove comprises the following steps:

[0120] A vulcanizing agent, a vulcanization accelerator and an antioxidant are mixed and ground to obtain a dispersion, and the dispersion, a hyperbranched polymer, antimony trioxide, aramid fiber, hydrogenated epoxidized natural rubber, zinc oxide, a stabilizer, polyoxyethylene castor oil and a softener are added to natural rubber latex and mixed evenly, and pre-vulcanized at 70° C. for 30 minutes to obtain a vulcanized latex;

[0121] The glove mold is impregnated with a coagulant and dried, impregnated with latex, shaped, leached, and curled after cooling; impregnated with latex for a second time, dried, demoulded, vulcanized in water at 80°C for 50 minutes, and then washed with chlorine and dried to obtain flame-retardant live-work gloves.

[0122] Test Case

[0123] The flame retardant live working gloves prepared in the above examples and comparative examples were subjected to the following performance tests, and the test results are shown in Table 1.

[0124] 1. Use GB / T17622-2008 "Insulating gloves for live working" to test electrical insulation performance, test breakdown voltage and leakage current, and conduct AC tests at 5KV and 10KV respectively to test whether there is breakdown. If there is no breakdown, it means that the breakdown voltage is greater than the test voltage. If there is a breakdown, it means that the breakdown voltage is less than the test voltage. If the breakdown voltage is greater than 10KV, the test is qualified.

[0125] 2. Carry out flame retardancy test in accordance with GB / T17622-2008 "Insulating gloves for live working". After the flame is extinguished, observe the spread of flame on the test piece. After 55 seconds, record the spread distance. If the burning flame does not spread to the 55mm reference line at the end of the test piece, the test is qualified.

[0126] 3. After the flame retardant live working gloves are placed at 80°C for 30 days, the puncture resistance performance is tested according to the mechanical puncture resistance test of GB / T17622-2008 "Insulating gloves for live working" standard to obtain the mechanical puncture strength.

[0127] The above tests were conducted at least 10 times in parallel and the average value was taken.

[0128] Table 1

[0129]

[0130]

[0131] In the above table, Comparative Examples 2 and 3 did not pass the 5 kV breakdown test, and thus the leakage current test at 5 kV was not performed.

[0132] It can be seen from Table 1 that the gloves of the present invention have excellent flame retardancy, insulation performance and puncture resistance (puncture strength).

[0133] According to Examples 1 to 4 and Comparative Examples 2 to 3, it can be seen that the present invention greatly improves the flame retardant properties, insulation properties and puncture resistance of the gloves under high temperature environments through the synergistic effect of antimony trioxide and aramid fiber, especially when the weight ratio of antimony trioxide to aramid fiber is (1.5 to 3.5): 1, the performance of the gloves is relatively better.

[0134] According to Examples 5 to 10 and Comparative Example 1, it can be seen that the gloves using hydrogenated epoxidized natural rubber have excellent insulation performance, puncture resistance and insulation performance. When the hydrogenation degree of the hydrogenated epoxidized natural rubber is 20 to 30% and the epoxidation degree of the epoxidized natural rubber is 50 to 65%, the effect of the gloves is better. According to Example 21, when the hydrogenated epoxidized natural rubber obtained by toluenesulfonyl hydrazide catalysis is not selectively hydrogenated at the double bond position, the epoxidation degree of the epoxidized natural rubber is changed, and the performance of the gloves is poor.

[0135] According to Examples 13 to 19, when the hyperbranched polymer is an amino-terminated hyperbranched polyamide, especially when the amino-terminated hyperbranched polyamide has 8 to 14 amino groups / mol and a molecular weight of 800 to 1600 g / mol, the gloves have better flame retardant properties, insulating properties and puncture resistance under high temperature environments.

[0136] According to Comparative Example 4, when antimony trioxide and aramid fiber are not mixed with the hyperbranched polymer by ultrasonic stirring but are directly mixed with other components such as natural rubber latex, the performance of the prepared gloves is poor.

[0137] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A flame retardant live working glove, characterized in that: The invention comprises the following components in parts by weight: 100 parts of natural latex, 8-15 parts of hydrogenated epoxidized natural rubber, 2-5 parts of hyperbranched polymer, 3-6 parts of antimony trioxide, 1-3 parts of aramid fiber, 1-4 parts of vulcanizing agent, 0.5-2 parts of vulcanization accelerator, 0.8-2 parts of antioxidant, 0.2-2 parts of zinc oxide, 0.1-1.5 parts of stabilizer, 0.1-0.25 parts of polyoxyethylene castor oil and 1-3 parts of softener; The natural latex is secondary centrifuged natural latex.

2. The flame retardant gloves for live working according to claim 1, characterized in that: The hydrogenated epoxidized natural rubber is prepared by carrying out a hydrogenation reaction of the epoxidized natural rubber in an autoclave under the catalysis of palladium acetate.

3. The flame retardant gloves for live working according to claim 1, characterized in that: The hydrogenation degree of the hydrogenated epoxidized natural rubber is 20-30%.

4. The flame retardant gloves for live working according to claim 2, characterized in that: The epoxidation degree of the epoxidized natural rubber is 50-65%.

5. The flame retardant gloves for live working according to claim 1, characterized in that: The hyperbranched polymer is selected from at least one of hydroxyl-terminated hyperbranched polyester, hydroxyl-terminated hyperbranched polyamide, carboxyl-terminated hyperbranched polyester, and amino-terminated hyperbranched polyamide.

6. The flame retardant gloves for live working according to claim 5, characterized in that: The hyperbranched polymer is amino-terminated hyperbranched polyamide.

7. The flame retardant gloves for live working according to claim 6, characterized in that: The number of terminal amino groups of the amino-terminated hyperbranched polyamide is 8 to 14 per mol.

8. The flame retardant gloves for live working according to claim 6, characterized in that: The molecular weight of the amino-terminated hyperbranched polyamide is 800-1600 g / mol.

9. The flame retardant gloves for live working according to claim 1, characterized in that: The weight ratio of the antimony trioxide to the aramid fiber is (1.5-3.5):

1.

10. The flame retardant gloves for live working according to claim 1, characterized in that: The ratio of the weight of the hyperbranched polymer to the sum of the weights of antimony trioxide and the aramid fiber is (0.4-0.6):

1.

11. The flame retardant gloves for live working according to claim 1, characterized in that: The average particle size of the antimony trioxide is 200-300 nm.

12. The flame retardant gloves for live working according to claim 1, characterized in that: The solid content of the secondary centrifuged natural latex is ≥60% and the water-soluble protein content is ≤90 μg / g.

13. The flame retardant gloves for live working according to claim 1, characterized in that: At least one of the following (a) to (d): (a) the stabilizer is perglase O; (b) the vulcanizing agent is sulfur; (c) the vulcanization accelerator is at least one of sodium dibutyl dithiocarbamate, dibenzothiazole disulfide, zinc dimethyl dithiocarbamate, and zinc ethylphenyl dithiocarbamate; (d) The antioxidant is at least one of antioxidant RD, antioxidant MB, and antioxidant 264.

14. The method for preparing the flame-retardant gloves for live working according to any one of claims 1 to 13, characterized in that: The following steps are involved: The hyperbranched polymer is mixed with antimony trioxide and aramid fiber, and then uniformly stirred by ultrasonication to obtain a mixture; The vulcanizing agent, the vulcanization accelerator and the antioxidant are mixed and then ground to obtain a dispersion; The mixture, dispersion, hydrogenated epoxidized natural rubber, zinc oxide, stabilizer, polyoxyethylene castor oil and softener are added to natural latex, mixed evenly, and pre-vulcanized to obtain vulcanized latex; The glove mold is impregnated with a coagulant and dried, impregnated with latex, shaped, leached, and curled after cooling; impregnated with latex for a second time, dried, demoulded, and water-vulcanized; then washed with chlorine and dried again to obtain flame-retardant live-work gloves.

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