Biodegradable butyronitrile glove and preparation method thereof

Abstract

The invention discloses a biodegradable butyronitrile glove and a preparation method thereof.The biodegradable butyronitrile glove has good biodegradability under the condition that the tensile strength, wear resistance and acid and alkali resistance of the glove are kept, and the glove can be used for preparing a glove through metabolism and enzyme effects in the natural environment; the glove can be degraded into organic matters and finally decomposed into natural elements, the problem that the butyronitrile glove is difficult to degrade is solved, and the natural environment is protected.

Description

Technical Field

[0001] The invention relates to a rubber material, in particular to a biodegradable nitrile glove and a preparation method thereof. Background Art

[0002] The protective role of gloves is becoming more and more important in many industries such as medical, food, electronics, and photovoltaics. The main types of gloves are polyvinyl chloride gloves, natural rubber gloves, nitrile gloves, etc. Among them, nitrile gloves are gradually replacing natural latex gloves because they do not contain the protein found in natural latex gloves and will not cause allergies when wearing gloves.

[0003] Nitrile, the main material of nitrile gloves, is a petroleum extract. After being discarded, traditional nitrile gloves have a long degradation cycle in the natural environment, which causes great pollution to the environment. In order to solve this problem, some degradable gloves have been developed.

[0004] For example, Chinese patent document CN 104718247 B (application number 201380052700.9) discloses a biodegradable elastomeric glove, which is formed by a composition comprising: a) acrylonitrile butadiene rubber latex; b) an alkaline stabilizer; c) a metal oxide crosslinker; and d) a biodegradation agent comprising a carboxylic acid compound. The alkaline stabilizer comprises an alkali metal hydroxide; the metal oxide crosslinker is zinc oxide or magnesium oxide; the carboxylic acid compound has a chain length of 5-18 carbons, and the biodegradation agent further comprises a chemical attractant compound; glutaric acid or its derivatives; and a swelling agent.

[0005] Chinese patent document CN 108250471 A (application number 201711495405.7) discloses a degradable and environmentally friendly rubber glove, comprising a glove body, wherein a photodegradable layer is provided on the outside of the glove body, and the glove body is composed of a rubber base and a photodegradation agent; the photodegradation agent is composed of iron stearate, polylactic acid, biodegradable PET, polyethylene succinate, polyester acid amine, starch and water.

[0006] For example, Chinese patent document CN 114196086 A (application number 202111581410.6) discloses an environmentally friendly and degradable nitrile glove, whose raw materials are as follows by weight: 200-300 parts of nitrile latex, 50-100 parts of polylactic acid, 1-2 parts of antistatic agent, 4-6 parts of adhesive, 7-9 parts of stabilizer, 2-5 parts of defoaming agent, 5-10 parts of plasticizer, and 20-30 parts of photosensitizer; by adding polylactic acid to the gloves, the gloves can have good transparency, softness and self-degradation performance, which is more conducive to environmental protection; the setting of the photosensitizer can degrade the gloves through light irradiation.

[0007] The degradation effect of the above two types of gloves containing photodegradants will be greatly affected if there is no light. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a biodegradable nitrile glove with a short degradation period and a preparation method thereof.

[0009] The technical solution for achieving the purpose of the present invention is a biodegradable nitrile glove, comprising rubber latex and a biodegradable auxiliary agent in a mass ratio of 90 to 110:1.

[0010] The rubber latex comprises the following components in parts by weight: 1000 parts of nitrile latex, 13-16 parts of potassium hydroxide, 8-12 parts of sulfur, 8-12 parts of zinc oxide, 13-16 parts of titanium dioxide, 2-6 parts of vulcanization modifier, and 3-6 parts of pre-vulcanization modifier.

[0011] The biodegradation aid comprises the following components in parts by weight: 0.5-3 parts of alkaloids, 80-120 parts of high molecular polymers, 3-8 parts of alginate, 3-8 parts of plant gum, 0.5-3 parts of keratin protein and 0.5-3 parts of calcium salt.

[0012] The vulcanization modifier is one or a combination of dimethyl sulfide, diethyl sulfide, and benzenepropanesulfonic acid.

[0013] The pre-vulcanization modifier is zinc di-n-butyl dithiocarbamate and / or zinc diethyl dithiocarbamate.

[0014] The alkaloid is one of dodecyl dimethyl betaine, tetradecyl dimethyl betaine, octadecyl dimethyl betaine, dodecyl dihydroxyethyl betaine and octadecyl dihydroxyethyl betaine, or a combination of more than one of the above.

[0015] The high molecular polymer is one or a combination of styrene-acrylonitrile copolymer, styrene-butadiene-styrene terpolymer, ethylene-acrylic acid copolymer, methyl vinyl ether-maleic acid copolymer.

[0016] The plant gum is one of sesbania gum, guar gum, flax gum, fenugreek gum and gum, or a combination of more than one of them.

[0017] The keratin protein is one or a combination of cashmere, yak hair, yak hair, camel hair, camel hair or other animal hair keratin protein fibers.

[0018] The calcium salt is one of calcium sulfate, calcium nitrate and calcium carbonate or a combination of more than one of them.

[0019] A method for preparing the biodegradable nitrile gloves as described above comprises the following steps:

[0020] ① Ingredients: Disperse potassium hydroxide weighed according to the formula in water, add nitrile latex, stir in a constant temperature water bath at 45±5°C for 0.5 to 1.5 hours, then add sulfur, zinc oxide, titanium dioxide, a vulcanization modifier and a pre-vulcanization modifier to obtain a mixed solution; add a biodegradable aid weighed according to the formula to the mixed solution, and mix well to obtain a degradable glove latex.

[0021] ② After cleaning the gloves, immerse them in a coagulant solution, and then immerse the hand mold immersed in the coagulant in the degradable glove latex; the glue film after immersion is cleaned with pure water, dried, and demolded to obtain nitrile gloves.

[0022] Furthermore, in step ②, the gloves are washed with water, washed with alkali, washed with water twice, dried, washed with chlorine, and then immersed in a coagulant solution.

[0023] The present invention has positive effects:

[0024] The biodegradable nitrile rubber gloves of the present invention have good biodegradability while maintaining the tensile strength, abrasion resistance and acid and alkali resistance of the gloves. Through metabolism and enzyme action in the natural environment, the gloves can be degraded into organic matter and finally decomposed into natural elements, thereby solving the problem that nitrile gloves are difficult to degrade and protecting the natural environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the original SEM photo of the degradable nitrile gloves in Experimental Example 1.

[0026] Figure 2 This is the SEM photo of the degradable nitrile gloves in Test Example 1 after 45 days in the soil.

[0027] Figure 3 This is the infrared spectrum of the degradable nitrile rubber glove sample before degradation.

[0028] Figure 4 This is the infrared spectrum of the biodegradable nitrile rubber glove sample after 15 days of degradation.

[0029] Figure 5 This is the infrared spectrum of the biodegradable nitrile rubber glove sample after 30 days of degradation.

[0030] Figure 6 This is the infrared spectrum of the biodegradable nitrile rubber glove sample after 45 days of degradation. DETAILED DESCRIPTION

[0031] (Example 1)

[0032] The biodegradable nitrile gloves of this embodiment include rubber latex and a biodegradation aid in a mass ratio of 100:1.

[0033] The rubber latex includes the following components in parts by weight: 1000 parts of nitrile latex, 15 parts of potassium hydroxide, 10 parts of sulfur, 10 parts of zinc oxide, 15 parts of titanium dioxide, 3 parts of vulcanization modifier, and 4 parts of pre-vulcanization modifier.

[0034] The vulcanization modifier is one or a combination of dimethyl sulfide, diethyl sulfide, and benzene propane sulfonic acid. In this embodiment, it is dimethyl sulfide.

[0035] The pre-vulcanization modifier is zinc di-n-butyl dithiocarbamate and / or zinc diethyl dithiocarbamate. In this embodiment, zinc di-n-butyl dithiocarbamate is used.

[0036] The biodegradable aid comprises the following components in parts by weight: 1 part of alkaloids, 100 parts of high molecular polymers, 5 parts of alginate, 5 parts of plant gum, 1 part of keratin protein and 1 part of calcium salt.

[0037] The alkaloid is one of dodecyl dimethyl betaine, tetradecyl dimethyl betaine, octadecyl dimethyl betaine, dodecyl dihydroxyethyl betaine, octadecyl dihydroxyethyl betaine, or a combination of more than one of the following. The alkaloid used in this embodiment is dodecyl dimethyl betaine.

[0038] The high molecular polymer is one or a combination of styrene-acrylonitrile copolymer, styrene-butadiene-styrene terpolymer, ethylene-acrylic acid copolymer, methyl vinyl ether-maleic acid copolymer. The high molecular polymer used in this embodiment is styrene-acrylonitrile copolymer.

[0039] The alginate is one of sodium alginate, calcium alginate, potassium alginate or a combination of more than one of them. In this embodiment, it is sodium alginate.

[0040] The plant gum is one or a combination of sesbania gum, guar gum, flax gum, fenugreek gum, and gum. The plant gum used in this embodiment is guar gum.

[0041] The keratin protein is one or a combination of cashmere, yak hair, yak hair, camel hair, camel hair or other animal hair keratin protein fibers, and in this embodiment, it is cashmere keratin protein fiber.

[0042] The calcium salt is one or a combination of calcium sulfate, calcium nitrate and calcium carbonate. The calcium salt used in this embodiment is calcium sulfate.

[0043] The preparation method of the biodegradable nitrile gloves of this embodiment comprises the following steps:

[0044] ①Ingredients.

[0045] 15 parts of potassium hydroxide weighed according to the formula were dispersed in 5 parts of water, nitrile latex was added, and after stirring in a constant temperature water bath at 45° C. for 1 hour, sulfur, zinc oxide, titanium dioxide, a vulcanization modifier and a pre-vulcanization modifier were added to obtain a mixed solution.

[0046] Add the biodegradable aid weighed according to the formula to the above mixed solution, and mix well to obtain the degradable glove latex.

[0047] ② The hand model is acid-washed, washed with water for the first time, washed with alkali, washed with water for the second time, and dried; the washed hand model is placed in a chlorine washing solution for chlorine washing; the chlorine-washed hand model is immersed in a coagulant solution; the immersed hand model is immersed in the degradable nitrile latex raw material for gloves; the immersed film is washed with pure water, dried, washed in water, and then dried again; the washed film is demoulded to prepare nitrile gloves.

[0048] (Example 2)

[0049] The rest of the nitrile gloves of this embodiment are the same as those of Embodiment 1, except that they include rubber latex and a biodegradable aid in a mass ratio of 95:1.

[0050] The rubber latex includes the following components in parts by weight: 1000 parts of nitrile latex, 15 parts of potassium hydroxide, 10 parts of sulfur, 10 parts of zinc oxide, 13 parts of titanium dioxide, 5 parts of vulcanization modifier, and 4 parts of pre-vulcanization modifier.

[0051] The biodegradable aid comprises the following components in parts by weight: 1 part of alkaloids, 100 parts of high molecular polymers, 5 parts of alginate, 5 parts of plant gum, 1 part of keratin protein and 1 part of calcium salt.

[0052] (Example 3)

[0053] The rest of the nitrile gloves of this embodiment are the same as those of Embodiment 1, except that they include rubber latex and a biodegradable aid in a mass ratio of 105:1.

[0054] The rubber latex includes the following components in parts by weight: 1000 parts of nitrile latex, 16 parts of potassium hydroxide, 12 parts of sulfur, 12 parts of zinc oxide, 15 parts of titanium dioxide, 4 parts of vulcanization modifier, and 5 parts of pre-vulcanization modifier.

[0055] The biodegradable aid comprises the following components in parts by weight: 1 part of alkaloids, 100 parts of high molecular polymers, 5 parts of alginate, 5 parts of plant gum, 1 part of keratin protein and 1 part of calcium salt.

[0056] (Example 4 to Example 11)

[0057] The rubber latex part of the nitrile gloves of Examples 4 to 11 is the same as that of Example 1, except that the composition of the biodegradation aid of each example is different from that of the biodegradation aid of Example 1.

[0058]

[0059]

[0060] (Test Example 1, soil burial biodegradation experiment)

[0061] Test objects: nitrile gloves prepared according to the formula and method of Example 1; ordinary nitrile gloves with model number 947D produced by Lipuduo (Lipuduo (Suzhou) Medical Technology Co., Ltd.); natural rubber gloves with model number R570 produced by Lipuduo.

[0062] Cut out three samples of 5cm*5cm from the palm of the nitrile gloves prepared according to the formula and method of Example 1; cut out three samples of 2cm*2cm from the palm of the ordinary nitrile gloves; cut out three samples of 2cm*2cm from the palm of the natural rubber gloves; wash each sample with distilled water, air dry it naturally, weigh it, and mark it. Divide the samples into three groups according to the material.

[0063] (I) The three groups of samples were buried 15 cm below the soil layer, taken out after 45 days of burial, washed with distilled water, naturally air-dried, and weighed. The degradation conditions and degradation rate calculation results are shown in Tables 1, 2 and 3 below (each group of data is the average of 3 samples, the same below):

[0064] Table 1. Degradation of biodegradable nitrile gloves in soil

[0065]

[0066] Table 2. Degradation of natural rubber gloves in soil

[0067]

[0068] Table 3. Degradation of ordinary nitrile gloves in soil

[0069]

[0070] The average degradation rate of the nitrile gloves samples in Example 1 after 45 days was 10.24%; the average degradation rate of the natural rubber gloves after 45 days was 2.64%; and the average degradation rate of the ordinary nitrile gloves after 45 days was 1.90%.

[0071] From the comparison of the three groups of experiments, it can be seen that the degradability of the nitrile gloves of the present invention is significantly improved.

[0072] (ii) Conduct comparison experiments using an element analyzer.

[0073] The initial carbon content of the three gloves was 60.5%. After 45 days:

[0074] The average carbon content of biodegradable nitrile gloves is 54.6%, a 9.8% reduction in carbon content.

[0075] The average carbon content of natural rubber gloves is 59.3%, and the carbon content is reduced to 2.05%.

[0076] The average carbon content of ordinary nitrile gloves is 59.6%, and the carbon content is reduced by 1.42%.

[0077] (III) See Figure 1 and Figure 2 , Figure 1 This is the original SEM photo of the biodegradable nitrile gloves. Figure 2 This is a SEM photo of the degradable nitrile gloves in soil for 45 days in Test Example 1. The SEM electron microscope shows that the surface of the degradable nitrile gloves gradually changes from uniform and dense to uneven, and the surface roughness increases.

[0078] (Test Example 2, natural water degradation experiment)

[0079] Cut out three samples of 5cm*5cm from the palm of the nitrile gloves prepared according to the formula and method of Example 1; cut out three samples of 2cm*2cm from the palm of the ordinary nitrile gloves; cut out three samples of 2cm*2cm from the palm of the natural rubber gloves; wash each sample with distilled water, air dry it naturally, weigh it, and mark it. Divide the samples into three groups according to the material.

[0080] The three groups of samples were placed in a simulated surface water environment, taken out after 45 days, washed with distilled water, and naturally air-dried. The weights were then weighed, and the degradation conditions and 45-day degradation rate calculation results are shown in Tables 4, 5, and 6:

[0081] Table 4. Degradation of nitrile gloves degradable in natural water

[0082]

[0083] Table 5. Degradation of natural rubber gloves in natural water

[0084]

[0085] Table 6. Degradation of ordinary nitrile gloves in natural water

[0086]

[0087] The 45-day degradation rate of the nitrile glove sample of Example 1 is 5.18%; the 45-day degradation rate of the natural rubber gloves is 1.77%; and the 45-day degradation rate of the ordinary nitrile gloves is 1.7%.

[0088] (Test Example 3, aerobic composting degradation experiment)

[0089] The three groups of glove samples came from the same source as in Test Example 1.

[0090] The final aerobic biodegradability of materials under controlled composting conditions was determined using the method of measuring released carbon dioxide GB / T19277.1-2011 / ISO 14855-1:2005, using vermiculite instead of compost. After vermiculite was inoculated and cultured in a culture medium containing organic matter, inorganic matter and mature compost, 4 kg was taken and put into an aerobic composting reactor, and 1 kg of crushed glove samples (area less than 2cm*2cm) were added. The experiment was run for 45 days.

[0091] (A) Degradation rate after 45 days.

[0092] The degradation rate of the degradable nitrile rubber gloves in Example 1 is the highest, with an average degradation rate of 10.81%, and the degradation is more obvious; the average degradation rates of natural rubber gloves and ordinary nitrile rubber gloves are 1.87% and 1.60%, respectively.

[0093] (ii) Carbon element analysis was performed on the three types of rubber gloves using an element analyzer.

[0094] The initial carbon content was 60.5%. After aerobic composting, the carbon content was reduced. The degradation rates of natural rubber gloves and ordinary nitrile rubber gloves were lower, 1.98% for natural rubber gloves and 1.79% for ordinary nitrile rubber gloves. The degradation rate of degradable nitrile rubber gloves was as high as 9.29%, with the best degradation effect.

[0095] (iii) Infrared characterization.

[0096] The infrared spectra of the biodegradable nitrile rubber gloves samples before degradation, 15 days, 30 days and 45 days are shown in Figures 3 to 6 .

[0097] It can be clearly seen from the infrared spectrum that after 45 days of degradation, the peak height and peak area of ​​the sample's characteristic peaks have been greatly reduced.

[0098] (Test Example 4, Glove Mechanical Properties Test)

[0099] The tensile strength and acid and alkali resistance of the nitrile gloves prepared according to the formula of Examples 1, 2, and 3 were tested, and the test results are as follows:

[0100]

[0101] From the above results, it can be seen that while improving the degradation performance, the tensile strength and acid and alkali resistance of the degradable gloves are still maintained.

Claims

1. A biodegradable nitrile glove, characterized in that: It includes rubber latex and a biodegradable additive in a mass ratio of 90 to 110:1; The rubber latex comprises the following components in parts by weight: 1000 parts of nitrile latex, 13-16 parts of potassium hydroxide, 8-12 parts of sulfur, 8-12 parts of zinc oxide, 13-16 parts of titanium dioxide, 2-6 parts of vulcanization modifier, and 3-6 parts of pre-vulcanization modifier; The biodegradation aid comprises the following components in parts by weight: 0.5-3 parts of alkaloids, 80-120 parts of high molecular polymers, 3-8 parts of alginate, 3-8 parts of plant gum, 0.5-3 parts of keratin protein and 0.5-3 parts of calcium salt.

2. The biodegradable nitrile gloves according to claim 1, characterized in that: The vulcanization modifier is one or a combination of dimethyl sulfide, diethyl sulfide, and benzenepropanesulfonic acid.

3. The biodegradable nitrile gloves according to claim 1, characterized in that: The pre-vulcanization modifier is zinc di-n-butyl dithiocarbamate and / or zinc diethyl dithiocarbamate.

4. The biodegradable nitrile gloves according to claim 1, characterized in that: The alkaloid is one of dodecyl dimethyl betaine, tetradecyl dimethyl betaine, octadecyl dimethyl betaine, dodecyl dihydroxyethyl betaine and octadecyl dihydroxyethyl betaine, or a combination of more than one of the above.

5. The biodegradable nitrile gloves according to claim 1, characterized in that: The high molecular polymer is one or a combination of styrene-acrylonitrile copolymer, styrene-butadiene-styrene terpolymer, ethylene-acrylic acid copolymer, methyl vinyl ether-maleic acid copolymer.

6. The biodegradable nitrile glove according to claim 1, characterized in that: The plant gum is one of sesbania gum, guar gum, flax gum, fenugreek gum and gum, or a combination of more than one of them.

7. The biodegradable nitrile glove according to claim 1, characterized in that: The keratin protein is one or a combination of cashmere, yak hair, yak hair, camel hair, camel hair or other animal hair keratin protein fibers.

8. The biodegradable nitrile glove according to claim 1, characterized in that: The calcium salt is one of calcium sulfate, calcium nitrate and calcium carbonate or a combination of more than one of them.

9. A method for preparing the biodegradable nitrile gloves as claimed in claim 1, characterized in that The following steps are involved: ① Ingredients: Disperse potassium hydroxide weighed according to the formula in water, add nitrile latex, stir in a constant temperature water bath at 45±5°C for 0.5 to 1.5 hours, then add sulfur, zinc oxide, titanium dioxide, a vulcanization modifier and a pre-vulcanization modifier to obtain a mixed solution; add a biodegradable aid weighed according to the formula to the mixed solution, and mix well to obtain a degradable glove latex; ② After cleaning the gloves, immerse them in a coagulant solution, and then immerse the hand mold immersed in the coagulant in the degradable glove latex; the glue film after immersion is cleaned with pure water, dried, and demolded to obtain nitrile gloves.

10. The method for preparing the biodegradable nitrile gloves according to claim 9, characterized in that: In step ②, the gloves are washed with water, washed with alkali, washed with water twice, dried, washed with chlorine, and then immersed in a coagulant solution.

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