阅读说明：本技术 一种防护口罩呼吸阀胶片的制备方法 (Preparation method of protective mask breather valve film ) 是由 汤现春 刘会珍 于 2020-12-09 设计创作，主要内容包括：本发明属于属于高分子材料领域,尤其是一种防护口罩呼吸阀胶片的制备方法,制备工艺简单、原料来源广泛,本发明公开的防护口罩呼吸阀胶片采用氧化锌复合银抗菌剂和接枝抗菌杜仲胶、以及聚丁二烯橡胶共混,即使防护口罩温暖、潮湿的环境,虽利于细菌的生长,呼吸阀胶片含有的杜仲天然抗菌成分和接枝组合物以及复合银系抗菌成分,可以渗透整个橡胶部件,为呼吸阀提供一个从表面到核心的完全保护,具有很好的安全性,无刺鼻气味,无毒无害。(The invention belongs to the field of high polymer materials, and particularly relates to a preparation method of a protective mask breather valve film, which is simple in preparation process and wide in raw material source.)

1. A preparation method of a protective mask breather valve film is characterized by comprising the following steps:

(1) adding 26-30 parts of 0.5-1 mol/L zinc nitrate solution, 28-32 parts of 0.1-0.15 mol/L silver nitrate solution and 10-12 parts of 25-28% concentrated ammonia water into a clean and dry reaction kettle in sequence, carrying out hydrolysis reaction at 45-50 ℃ for 10-15 min at a fixed stirring speed, then dropwise adding 12-16 parts of 0.5-1 mol/L ammonium carbonate solution at a speed of 3 parts/min by using a peristaltic pump, continuously stirring and reacting for 10-15 min at the same temperature, transferring the reaction liquid into a centrifuge tube, setting the rotation speed of the centrifuge to 8000-10000 r/min, centrifugally separating for 10-20 min, discarding supernatant, washing the precipitate twice by using distilled water to remove soluble impurities in the precipitate twice, then washing twice by using absolute ethyl alcohol, then drying at 60 ℃ to constant weight to obtain a precursor of the composite nano antibacterial agent;

(2) placing a precursor sample in a muffle furnace, firstly heating to 200 ℃, preserving heat for 90min, then heating to a set calcination temperature of 600-650 ℃, preserving heat for 240min, decomposing the precursor to obtain a zinc oxide-coated silver composite nano antibacterial agent, cooling along with the furnace, and taking out to obtain the zinc oxide-coated silver composite nano antibacterial agent;

(3) in a reaction kettle provided with a reflux condenser tube, a mechanical stirrer, a constant pressure funnel and a thermometer according to the parts by weight, adding 110-120 parts of toluene and 45-50 parts of eucommia ulmoides gum, heating to 50-60 ℃, after the natural rubber is fully dissolved in the toluene, then continuously heating to the reaction temperature of 75-80 ℃, dropwise adding a mixture of 34-36 parts of dimethylaminoethyl methacrylate and 0.2-0.4 part of dibenzoyl peroxide as an initiator at a constant speed for 15-20 min, keeping the temperature, stirring and reacting for 25-30 min, after the reaction is finished, pouring out the mixture, precipitating and separating with methanol, vacuum drying the precipitate at 60 deg.C to constant weight to obtain graft product, placing the dried graft product into Soxhlet extractor, extracting for 12-24 h by using methanol as a solvent, separating a homopolymer, and drying an extraction product at 50-60 ℃ in vacuum to constant weight to obtain eucommia ulmoides gum grafted poly (dimethylaminoethyl methacrylate); (4) according to parts by weight, 45-52 parts of eucommia ulmoides gum grafted poly (dimethylaminoethyl methacrylate), 25-30 parts of polybutadiene rubber, 15-18 parts of rubber oil, 1-2 parts of white carbon black, 3-4 parts of zinc oxide, 1-2 parts of a zinc oxide coated silver composite nano antibacterial agent, 0.5-1 part of an anti-aging agent and 0.5-1 part of a cross-linking agent are added into an open mixing roll according to a proportion for plastication, 2-4 parts of flake graphite, 1-2 parts of microcrystalline wax, 0.5-1 part of a cross-linking promoter and 0.2-0.4 part of a silane cross-linking agent are added after a rubber roll is coated, wherein the temperature of the mixing roll is 85-90 ℃, the rotating speed of a rotor is 30-45 r/min, the mixture is put into a vulcanizing machine for vulcanization, and the mixture is taken out under the pressurization condition of 140-150 ℃ and 13-15 MPa for 10-15 min.

2. The method for preparing a respirator breather valve film according to claim 1, wherein the cross-linking agent in step (4) is one of dicumyl peroxide, 1, 3-bis (t-butylperoxyisopropyl) or bis- (2, 4-dichlorobenzoyl peroxide).

3. The method for preparing a respirator breather valve film according to claim 1, wherein the rubber oil in step (4) is selected from any one of white oil and naphthenic oil or a mixture of at least two of the white oil and the naphthenic oil in any proportion, and the flash point of the rubber oil is more than 256 ℃.

4. The method for preparing a respiratory valve film of a protective mask according to claim 1, wherein the anti-aging agent in step (4) is one of bis (3, 5-di-tert-butyl-4-hydroxybenzyl) sulfide, diphenyl-octyl phosphite and 2-mercaptobenzimidazole.

5. The method for preparing a respiratory valve film of a protective mask according to claim 1, wherein the crosslinking promoter in step (4) is one of acetaldehyde ammonia (1-aminoethanol), triallyl isocyanurate and dibenzothiazyl disulfide.

6. The method for preparing a respirator breather valve film according to claim 1, wherein the silane cross-linking agent in step (4) is one of bis- (γ -triethoxysilylpropyl) tetrasulfide and bis- [3- (triethoxysilyl) propyl ] -disulfide.

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to a preparation method of a protective mask breather valve film.

Background

The mask is an important defense line for preventing respiratory infectious diseases, can prevent a patient from spraying droplets, reduce the amount of the droplets and the spraying speed, can block droplet nuclei containing viruses, prevents the inhalation of a wearer, and reduces the risk of virus infection. The respirator is provided with the breather valve without worry. The airflow of the breather valve is one-way outward, and the protection effect of a user is not influenced. However, people who have symptoms have suggested not to use a respirator with a breather valve because it cannot block the escape of viral droplets. The respirator is a breather valve with a rubber pad, the breather valve is opened when a user exhales, waste gas is discharged, and the breather valve is closed when the user inhales, so that dirty air is prevented from entering. N95 has outstanding protective effect in preventing droplet infection caused by splashing of body fluid or blood of a patient and other types of respiratory infection problems. The N95 mask is usually provided with a breather valve device which is shaped like a pig mouth, so the N95 is also commonly called a piglet mouth mask. The function of the breather valve is to make the respiratory flow and the inspiratory flow in the inlet cover flow in a single direction, even if the inhaled air is purified by the filter material and then is inhaled into the breathing system; the moisture gas exhaled by the human body is directly discharged into the atmosphere through the exhalation valve, so that the filter material is not soaked, and the using effect of the filter material is not affected. However, most masks without a breather valve are not limited by whether the breather valve has good air tightness or not. The unidirectional breathing pottery is made of high-quality rubber and has the advantages of small air resistance, low starting pressure, firmness and convenience in disinfection. During inspiration, the air bag is compressed, and air flow enters the respiratory tract through the mouth of the fish mouth of the humidifier and the breather valve, wherein the temperature of the humidifier and the breather valve can be adjusted. It can be seen that the breather valve film has an important influence on the protection performance of the mask, and the previous breather valve film does not have an antibacterial function, and a preparation method of the breather valve film of the protection mask needs to be developed urgently by technical personnel in the field so as to meet the existing performance requirements and use requirements.

Disclosure of Invention

Aiming at the problems, the invention aims to provide a preparation method of a breather valve film of a protective mask.

The invention is realized by the following technical scheme:

a preparation method of a protective mask breather valve film comprises the following steps:

(1) adding 26-30 parts of 0.5-1 mol/L zinc nitrate solution, 28-32 parts of 0.1-0.15 mol/L silver nitrate solution and 10-12 parts of 25-28% concentrated ammonia water into a clean and dry reaction kettle in sequence, carrying out hydrolysis reaction at 45-50 ℃ for 10-15 min at a fixed stirring speed, then dropwise adding 12-16 parts of 0.5-1 mol/L ammonium carbonate solution at a speed of 3 parts/min by using a peristaltic pump, continuously stirring and reacting for 10-15 min at the same temperature, transferring the reaction liquid into a centrifuge tube, setting the rotation speed of the centrifuge to 8000-10000 r/min, centrifugally separating for 10-20 min, discarding supernatant, washing the precipitate twice by using distilled water to remove soluble impurities in the precipitate twice, then washing twice by using absolute ethyl alcohol, then drying at 60 ℃ to constant weight to obtain a precursor of the composite nano antibacterial agent;

(2) placing a precursor sample in a muffle furnace, firstly heating to 200 ℃, preserving heat for 90min, then heating to a set calcination temperature of 600-650 ℃, preserving heat for 240min, decomposing the precursor to obtain a zinc oxide-coated silver composite nano antibacterial agent, cooling along with the furnace, and taking out to obtain the zinc oxide-coated silver composite nano antibacterial agent;

(3) in a reaction kettle provided with a reflux condenser tube, a mechanical stirrer, a constant pressure funnel and a thermometer according to the parts by weight, adding 110-120 parts of toluene and 45-50 parts of eucommia ulmoides gum, heating to 50-60 ℃, after the natural rubber is fully dissolved in the toluene, then continuously heating to the reaction temperature of 75-80 ℃, dropwise adding a mixture of 34-36 parts of dimethylaminoethyl methacrylate and 0.2-0.4 part of dibenzoyl peroxide as an initiator at a constant speed for 15-20 min, keeping the temperature, stirring and reacting for 25-30 min, after the reaction is finished, pouring out the mixture, precipitating and separating with methanol, vacuum drying the precipitate at 60 deg.C to constant weight to obtain graft product, placing the dried graft product into Soxhlet extractor, extracting for 12-24 h by using methanol as a solvent, separating a homopolymer, and drying an extraction product at 50-60 ℃ in vacuum to constant weight to obtain eucommia ulmoides gum grafted poly (dimethylaminoethyl methacrylate); (4) according to parts by weight, 45-52 parts of eucommia ulmoides gum grafted poly (dimethylaminoethyl methacrylate), 25-30 parts of polybutadiene rubber, 15-18 parts of rubber oil, 1-2 parts of white carbon black, 3-4 parts of zinc oxide, 1-2 parts of a zinc oxide coated silver composite nano antibacterial agent, 0.5-1 part of an anti-aging agent and 0.5-1 part of a cross-linking agent are added into an open mixing roll according to a proportion for plastication, 2-4 parts of flake graphite, 1-2 parts of microcrystalline wax, 0.5-1 part of a cross-linking promoter and 0.2-0.4 part of a silane cross-linking agent are added after a rubber roll is coated, wherein the temperature of the mixing roll is 85-90 ℃, the rotating speed of a rotor is 30-45 r/min, the mixture is put into a vulcanizing machine for vulcanization, and the mixture is taken out under the pressurization condition of 140-150 ℃ and 13-15 MPa for 10-15 min.

Further, in the step (4), the cross-linking agent is one of dicumyl peroxide, 1, 3-bis (tert-butylperoxyisopropyl) or bis- (2, 4-dichlorobenzoyl peroxide).

Further, the rubber oil in the step (4) is selected from any one of white oil and naphthenic oil or a mixture of at least two of the white oil and the naphthenic oil in any proportion, and the flash point of the rubber oil is more than 256 ℃.

Further, in the step (4), the anti-aging agent is one of bis (3, 5-di-tert-butyl-4-hydroxybenzyl) sulfide, diphenyl-octyl phosphite and 2-mercaptobenzimidazole.

Further, in the step (4), the crosslinking accelerator is one of acetaldehyde ammonia (1-aminoethanol), triallyl isocyanurate and dibenzothiazyl disulfide.

Further, the silane cross-linking agent in the step (4) is one of bis- (gamma-triethoxysilylpropyl) tetrasulfide and bis- [3- (triethoxysilyl) propyl ] -disulfide.

The invention has the beneficial effects that:

the invention takes dimethylaminoethyl methacrylate as raw material to graft and modify gutta-percha, the natural gutta-percha has certain antibacterial activity, the antibacterial activity is improved after the grafting modification, the high antibacterial activity and the efficiency are further improved and maintained, the cationic charge density is increased, the antibacterial activity is improved, the antibacterial ability to bacteria is stronger, the toxicity to people and animals is low, the silane cross-linking agent can play a bridging role between polybutadiene rubber and gutta-percha linear molecules, thereby a plurality of linear molecules or slightly branched chain type macromolecules and macromolecules are mutually bonded and cross-linked into a three-dimensional network structure, the formation of covalent bonds or ionic bonds between polymer molecular chains is promoted or regulated, the preparation method of the composite silver antibacterial agent is simple and convenient, the antibacterial and mildew-proof performance is further improved, the strength and the hardness of the blended and mixed rubber are improved, the composite silver antibacterial agent is more suitable for the sealing movement of a breather valve, and the breath in the mouth cover can be better, The air flow flows in one direction, even if the air is purified by the filter material and then sucked into the respiratory system, the moisture gas exhaled by the human body is directly discharged into the atmosphere through the exhalation valve, so that the filter material of the mask is not soaked, and the using effect of the respiration valve is not influenced.

Compared with the prior art, the invention has the following advantages:

the protective mask breather valve film disclosed by the invention adopts the blending of the zinc oxide composite silver antibacterial agent, the grafted antibacterial gutta percha and the polybutadiene rubber, so that even though the protective mask is in a warm and humid environment, the growth of bacteria is facilitated, the natural antibacterial component, the grafted composition and the composite silver antibacterial component of the eucommia bark contained in the breather valve film can permeate the whole rubber part, and the breather valve is completely protected from the surface to the core, so that the safety is good, no pungent smell exists, and the breather valve film is non-toxic and harmless.

Detailed Description

The invention is illustrated by the following specific examples, which are not intended to be limiting.

Example 1

(1) Adding 30 parts of zinc nitrate solution with the set concentration of 1mol/L, 32 parts of silver nitrate solution with the set concentration of 0.15mol/L and 12 parts of strong ammonia water with the mass percentage of 28 percent into a clean and dry reaction kettle in sequence, fixing the stirring speed to 1500r/min, carrying out hydrolysis reaction at 50 ℃ for 15min, then dripping 16 parts of ammonium carbonate solution with the set concentration of 1mol/L by using a peristaltic pump at the speed of 3 parts/min, continuously stirring and reacting at the same temperature for 15min, transferring the reaction solution into a centrifuge tube, setting the rotation speed of the centrifuge to 10000r/min, centrifuging for 20min, discarding the supernatant, washing the precipitate with distilled water twice, removing soluble impurities in the precipitate, washing twice by using absolute ethyl alcohol, and drying at 60 ℃ to constant weight to obtain a precursor of the composite nano antibacterial agent; (2) placing the precursor sample in a muffle furnace, firstly heating to 200 ℃, preserving heat for 90min, then heating to a set calcination temperature of 650 ℃, preserving heat for 240min, decomposing the precursor to obtain the zinc oxide-coated silver composite nano antibacterial agent, cooling along with the furnace, and taking out the zinc oxide-coated silver composite nano antibacterial agent to obtain the zinc oxide-coated silver composite nano antibacterial agent; (3) adding 120 parts of toluene and 50 parts of gutta-percha into a reaction kettle provided with a reflux condenser pipe, a mechanical stirrer, a constant-pressure funnel and a thermometer according to parts by weight, heating to 60 ℃, continuously heating to 80 ℃ after natural rubber is fully dissolved in the toluene, dripping a mixture of 36 parts of dimethylaminoethyl methacrylate and 0.4 part of dibenzoyl peroxide as an initiator at a constant speed for 20min, carrying out heat preservation and stirring reaction for 30min, pouring out the mixture after the reaction is finished, carrying out precipitation separation by using methanol, carrying out vacuum drying on the precipitate at 60 ℃ to constant weight to obtain a grafted product, putting the dried grafted product into a Soxhlet extractor, extracting for 24h by using the methanol as a solvent, separating out a homopolymer, and carrying out vacuum drying on the extracted product at 60 ℃ to constant weight to obtain the eucommia ulmoides rubber grafted dimethylaminoethyl methacrylate; (4) according to parts by weight, adding 52 parts of eucommia ulmoides gum grafted poly (dimethylaminoethyl methacrylate), 4 parts of zinc oxide, 2 parts of zinc oxide coated silver composite nano antibacterial agent, 30 parts of polybutadiene rubber, 18 parts of rubber oil naphthenic oil, 2 parts of white carbon black, 1 part of anti-aging agent and 1 part of cross-linking agent into an open mixing roll according to a proportion for plastication, adding 2 parts of flake graphite, 1 part of microcrystalline paraffin, 1 part of cross-linking accelerator and 0.4 part of silane cross-linking agent after a rubber coating roll is produced, placing the mixture into a vulcanizing machine for vulcanization under the conditions of 150 ℃ and 15MPa for 15min, and discharging the sheet to obtain the nano composite rubber coating, wherein the cross-linking agent in the step (4) is 1, 3-bis (tert-butylperoxyisopropyl), the rubber oil in the step (4) is naphthenic oil Xinjiang Keyimalan-4006, the anti-aging agent in the step (4) is bis (3, 5-di-tert-butyl-4-hydroxybenzyl) sulfide, the crosslinking accelerator in the step (4) is acetaldehyde ammonia (1-aminoethanol), the silane crosslinking agent in the step (4) is bis- [3- (triethoxysilyl) propyl ] -disulfide, specifically Si-75 Germany Degussa, EUG ZP 120 of eucommia ulmoides Yatongbeiron eucommia ulmoides bioengineering Co., Ltd, the flake graphite is F-1 of Shandong Jinhai graphite products Co., Ltd, polybutadiene rubber Rui (Rusheng) 1250H, the microcrystalline paraffin is purchased from sonneborn W445, the white carbon Xinjiang Changshao HL-200, and the zinc oxide is purchased from Jinhua zinc oxide factory in Shanxi county.

Example 2

A-1289 of bis- (gamma-triethoxysilylpropyl) tetrasulfide GE/OSi company, EUG ZP 090 of eucommia ulmoides rubber Shandong Belong eucommia ulmoides bioengineering Co., Ltd, F-1 of Shandong Jinhai graphite products Co., Ltd, polybutadiene rubber BR9000, microcrystalline paraffin from sonneborn W445, white carbon black Xinjiang Changshao HL-200, and zinc oxide from Kao Hua zinc oxide factory in Shanxi county. (1) 26 parts of zinc nitrate solution with the set amount concentration of 0.5mol/L, 28 parts of silver nitrate solution with the set amount concentration of 0.1mol/L and 10 parts of strong ammonia water with the mass percentage content of 25 percent are sequentially added into a clean and dry reaction kettle, the fixed stirring speed is 1000r/min, hydrolysis reaction is carried out at 45 ℃ for 10min, 12 parts of ammonium carbonate solution with the set concentration of 0.5mol/L is dripped by a peristaltic pump at the speed of 3 parts/min, continuously stirring and reacting at the same temperature for 10min, transferring the reaction solution into a centrifuge tube, setting the rotation speed of the centrifuge at 8000r/min, centrifuging for 10min, discarding the supernatant, washing the precipitate with distilled water twice, removing soluble impurities in the precipitate, washing twice by using absolute ethyl alcohol, and drying at 60 ℃ to constant weight to obtain a precursor of the composite nano antibacterial agent; (2) placing the precursor sample in a muffle furnace, firstly heating to 200 ℃, preserving heat for 90min, then heating to a set calcination temperature of 600 ℃, preserving heat for 240min, decomposing the precursor to obtain the zinc oxide-coated silver composite nano antibacterial agent, cooling along with the furnace, and taking out the zinc oxide-coated silver composite nano antibacterial agent to obtain the zinc oxide-coated silver composite nano antibacterial agent; (3) adding 120 parts of toluene and 45 parts of eucommia ulmoides gum into a reaction kettle provided with a reflux condenser pipe, a mechanical stirrer, a constant-pressure funnel and a thermometer according to parts by weight, heating to 50 ℃, continuously heating to 75 ℃ after natural rubber is fully dissolved in the toluene, dripping a mixture of 34 parts of dimethylaminoethyl methacrylate and 0.2 part of dibenzoyl peroxide as an initiator at a constant speed for 15min, carrying out heat preservation and stirring reaction for 25min, pouring out the mixture after the reaction is finished, carrying out precipitation separation by using methanol, carrying out vacuum drying on the precipitate at 60 ℃ to constant weight to obtain a graft product, putting the dried graft product into a Soxhlet extractor, extracting for 12h by using the methanol as a solvent, separating out a homopolymer, and carrying out vacuum drying on the extract product at 50 ℃ to constant weight to obtain the eucommia ulmoides gum grafted polydimethylaminoethyl methacrylate; (4) according to the weight parts, 45 parts of eucommia ulmoides gum grafted poly (dimethylaminoethyl methacrylate), 25 parts of polybutadiene rubber, 15 parts of rubber oil 46# white oil, 1 part of white carbon black, 3 parts of zinc oxide, 1 part of zinc oxide coated silver composite nano antibacterial agent, 0.5 part of anti-aging agent and 0.5 part of cross-linking agent are added into an open mixing roll according to the proportion for plastication, 2 parts of flake graphite, 1 part of microcrystalline paraffin, 0.5 part of cross-linking accelerator and 0.2 part of silane cross-linking agent are added after raw rubber is coated on a roll, wherein the temperature of the mixing roll is 85 ℃, the rotating speed of a rotor is 30r/min, the mixture is put into a vulcanizing machine for vulcanization, the vulcanization condition is 140 ℃, the pressurization is carried out at 13MPa for 10min, and the sheet is taken out, wherein the cross-linking agent in the step (4) is bis- (2, 4-dichlorobenzoyl) and the rubber oil in the step (4) is selected from the medium sea oil 46#, the anti-aging agent in the step (4) is bis (3, 5-di-tert-butyl-4-hydroxybenzyl) sulfide, the crosslinking accelerator in the step (4) is triallyl isocyanurate, and the silane crosslinking agent in the step (4) is bis- (gamma-triethoxysilylpropyl) tetrasulfide.

Comparative example 1

In this comparative example 1, compared with example 1, no polybutadiene rubber was used in the step (4), except that the other steps were the same.

Comparative example 2

In this comparative example 2, compared with example 2, the gutta percha grafted polydimethylaminoethyl methacrylate in the step (4) was replaced with gutta percha, and the steps were the same except for the above.

Comparative example 3

This comparative example 3 compares to example 2, in step (4) no zinc oxide coated silver composite nano antibacterial agent is used, except that the other process steps are the same.

The physical and chemical properties of the films of the breathing valve of the protective mask in examples 1 to 2 and comparative examples 1 to 3 were measured

Table 1 comparison results of physical and chemical property tests of films of breathing valves of protective masks in examples and comparative examples 1 to 3

Item	Example 1	Example 2	Comparative example 1	Comparative example 2	Comparative example 3
						Tensile strength MPa	16.8	16.3	18.2	6.5	16.1
Elongation at break%	423.1	438.7	424.3	466.5	432.9
						100% stress at definite elongation MPa	4.4	4.3	4.9	2.8	3.4
Mildew resistance rating	0	0	0	1	1
						Antibacterial property	99.9	99.9	99.9	99.9	99.9

Note: preparing a sample and adjusting a general program by a GB/T2941 rubber physical experiment method; GB/T531.1-2008 vulcanized rubber or thermoplastic rubber press-in hardness test method part one: shore durometer (shore hardness); GB/T528-2006 vulcanized rubber or thermoplastic rubber tensile stress strain performance measurement; QB/T2591-; HG/T4301-2012 rubber mildew resistance test method.