Preparation method of an antibacterial, conductive, special-shaped hydrogel breathing mask

Abstract

The present application relates to the field of high polymer materials and medical devices, and particularly relates to a preparation method of an antibacterial, conductive, special-shaped hydrogel breathing mask. The preparation method comprises the following steps: gel prepolymer liquid preparation, mold assembly, glue injection, hydrogel breathing mask forming, cutting and packaging of the hydrogel breathing mask. The present application first uses a hydrogel to prepare a special-shaped breathing mask, and the hydrogel has the advantages of soft texture, smooth surface, good toughness, high air permeability, good biocompatibility and the like. After molding in a mold, the hydrogel breathing mask is prepared by processing, can partially replace the breathing masks made of silica gel and the like on the market, and has antibacterial and conductive properties at the same time. The hydrogel breathing mask can be used in the respiratory field, can monitor the breathing condition of a patient in real time, can dynamically monitor and treat diseases such as chronic obstructive pulmonary disease, respiratory insufficiency, sleep apnea syndrome and the like, and can provide high-quality products for a large number of patients with respiratory diseases.

Description

Technical Field

[0001] The present invention relates to the fields of polymer materials and medical devices, and in particular to a method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask. Background Art

[0002] In recent years, with the intensification of global pollution, deterioration of air quality, and the aging of the population, respiratory diseases are becoming increasingly prevalent, with incidence rates increasing year by year, and have become one of the leading causes of death among Chinese residents. Chronic obstructive pulmonary disease (COPD) is currently the fourth leading cause of death worldwide. According to the World Bank / World Health Organization, by 2020, COPD will rank fifth in the world's economic burden of disease. In China, asthma and COPD are the most common chronic respiratory diseases. Relevant data show that the asthma incidence rate among Chinese children and adolescents is 4%, with a diagnosis and treatment rate of 86%, while the asthma incidence rate among adults is 1.78%, with a diagnosis and treatment rate of only 39%. The increase in the number of COPD patients has made respiratory diseases one of the main factors in shortening life expectancy in my country, and is also one of the important factors driving the growth of the ventilator market.

[0003] A ventilator is a device that helps patients breathe when their blood oxygen levels are low, helping them regain normal breathing. The mask is the interface between the ventilator and the patient's skin. It mainly comes in nasal masks, nasal pillows, and full-face masks. Nasal masks only cover the nose, and the nose portion is typically triangular. Currently, ventilator masks are made of polyvinyl chloride (PVC), thermoplastic polyurethane (TPU), and silicone. PVC is less comfortable and poses a significant environmental risk. While TPU is more environmentally friendly than PVC, it is difficult to mold. Silicone, while soft, has excellent toughness and elasticity, ensuring a good seal at the facial joint. It is also environmentally friendly and non-toxic, making it a commonly used material. However, prolonged wearing of a silicone mask can cause localized facial heat buildup, facial pressure, and poor blood flow, potentially leading to device-related pressure injury (DRPI) in the compressed skin of the nose and face, increasing patient discomfort. Because the patient's facial skin fat is thin and the bones are protruding when the respiratory mask is covered, long-term contact will compress the facial blood vessels and form pressure sores, causing skin erythema or damage, triggering infection, aggravating the patient's discomfort, and reducing the patient's tolerance and compliance with ventilation treatment, thereby affecting the treatment effect of the primary disease.

[0004] The current methods to improve the skin pressure injury caused by respiratory masks mainly include: (1) improving the structure of the respiratory mask to make it fit the patient's facial structure better, but the facial bones of each patient are different and it is difficult to meet the needs; (2) adding and improving the protective pad of the respiratory mask so that the softer protective pad is in direct contact with the skin to reduce the damage caused by the mask to the skin.

[0005] In 2019, Guo Yuehong et al. (patent application number: 201922392752.8) announced a special protective pad for medical sterile masks. This product is a special-shaped silicone gel composite protective pad. The protective pad body is composed of three layers of materials. The porous silicone gel layer is used to stick the mask device to the skin around the patient's mouth and nose. The PU (Polyurethane) waterproof membrane is in contact with the inner wall of the respiratory mask to protect the skin and avoid skin ulcers caused by wearing the respiratory mask for a long time to avoid secondary damage. The highly absorbent foam cotton layer can absorb sweat on the skin surface, so that the skin surface maintains optimal humidity and improves the patient's comfort.

[0006] Although silicone gel is a soft material, it still has drawbacks such as poor oxygen permeability, poor water absorption, susceptibility to aging, and the risk of sores, limiting its application in respiratory masks. Hydrogel, on the other hand, is a material with high oxygen permeability, is soft, easily adheres to the skin, and absorbs skin exudates. It has been used clinically to replace traditional silicone gel or gauze materials. It can also be combined with traditional respiratory masks, directly adhering to the skin to improve ventilation and cleanliness of the skin under pressure, and prevent facial pressure injuries.

[0007] Zhang Hua (Clinical Effect of Hydrocolloid Dressing in Preventing Pressure Ulcers Caused by Non-invasive Ventilation Masks in Severely Ill Bedridden Patients [J]. Dermatology and Venereology, 2020, 42(2): 296-297) has used hydrogel dressings in clinical practice from 2016 to 2020. Hydrogel dressings are applied to the areas of the face compressed by masks on some patients. The dressings are soft in texture and smooth in surface, can be firmly adhered to the skin at the edge of the wound, have good air permeability, and can completely absorb wound exudate. The hydrophilic particles in the material rapidly expand and deform after absorbing the exudate, covering the wound in a semi-solid state, providing and maintaining an appropriate moist environment to promote wound healing. At the same time, the dressing has good viscosity and forms a closed environment in close contact with the skin, which can promote macrophages to remove necrotic tissue and accelerate tissue regeneration and healing. The dressing contains endogenous enzymes that can perform a debridement function. In this study, the incidence of pressure ulcers in patients using hydrocolloid dressings was only 4.00%, while the incidence was as high as 24.00% in patients using traditional prevention methods. Furthermore, no patients using hydrocolloid dressings developed Stage III or Stage IV pressure ulcers, while there were three Stage III cases in patients using traditional prevention methods, demonstrating the significant effectiveness of hydrocolloid dressings in preventing pressure ulcers. Furthermore, the rates of mask discomfort and skin discomfort in patients using hydrocolloid dressings were significantly lower than those in patients receiving conventional care, effectively demonstrating that hydrocolloid dressings mitigate the adverse effects of ventilation mask use and significantly improve patient comfort.

[0008] Tang Li (Tang Li. Effect of Ampu Patching Hydrogel on Comfort and Incidence of Skin Injury in Patients with AECOPD (Acute Exacerbation of Chronic Obstructive Pulmonary Disease, abbreviated as AECOPD) Combined with Type II Respiratory Failure [J]. Disease Monitoring and Control, 2019, 13(6): 492-496) Research shows that using Ampu Patching Hydrogel dressing to protect the sides of the face and the root of the nose can improve the comfort of the face of patients with AECOPD combined with Type II respiratory failure who are mechanically ventilated. The reason may be that this method can cut the Ampu Patching Hydrogel dressing of appropriate size according to the characteristics of the nose and face of patients with AECOPD combined with Type II respiratory failure who are mechanically ventilated, and then apply it to the pressure-bearing areas such as the sides of the face and the root of the nose, which not only forms a protective cushion between the mask or nasal mask and the skin, but also improves the patient's facial comfort.

[0009] Based on the above analysis, it can be seen that although the existing silicone respiratory masks are made of soft materials, they have poor oxygen permeability, poor water absorption, easy aging and sore-causing properties. Hydrogel materials with high mechanical properties, good water permeability and air permeability, high moisture retention, excellent biological activity and biocompatibility are used in respiratory masks, and are mostly used in the form of dressings as respiratory mask gaskets. However, it is rare to directly replace traditional silicone materials with hydrogel materials to prepare respiratory masks. In fact, using hydrogels in respiratory masks can not only effectively prevent facial pressure sores, but also, compared with respiratory masks combined with hydrogel dressings, special-shaped hydrogel respiratory masks use one-piece molding technology based on 3D printing molds, which has a simple process, high cost-effectiveness, and can achieve green production. In particular, the hydrogel respiratory mask of the present invention has both antibacterial and electrical conductivity, can monitor the patient's breathing condition in real time, dynamically monitor and treat diseases such as chronic obstructive pulmonary disease, respiratory insufficiency, sleep apnea syndrome, etc., and provide high-quality products for the majority of patients with respiratory diseases. Summary of the Invention

[0010] The purpose of the present invention is to provide a method for preparing an antibacterial, conductive, and special-shaped hydrogel respiratory mask. The method is simple to operate, has a rapid reaction, and has excellent performance and can be mass-produced. The prepared hydrogel respiratory mask utilizes the high transparency, high toughness, antibacterial and conductive properties of the hydrogel and can be used as a new soft material gel respiratory mask to replace the traditional nasal mask-type silicone mask. It can be used in the medical device and respiratory fields to provide respiratory patients with unobstructed breathing.

[0011] To achieve the above objectives, the present invention provides a method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask, comprising the following steps:

[0012] (1) Preparation of gel prepolymer solution: monomers, crosslinking agents, conductive ions and auxiliary agents including any one of a liquid universal compound antibacterial agent, an antioxidant, a moisturizer and a water-soluble pigment or a mixture thereof are sequentially added to deionized water, heated in a water bath to 20-100° C. and stirred for 30-120 min. After a uniform mixed solution is formed, the solution is taken out and placed in a 0.01-1 MPa vacuum box for degassing for 0.5-2 h. Subsequently, the mixed solution is heated in a water bath at 20-100° C. and the diluted initiator and catalyst are sequentially added, and slowly stirred for 5-30 min to obtain a gel prepolymer solution.

[0013] (2) Mold assembly: Assemble the upper mold, lower mold, upper flap embedded core, and lower flap embedded core of the 3D printed respiratory mask plastic mold in the order of assembly, seal the boundary gaps of the mold assembly, and leave only three glue injection ports on the upper surface of the mold and one glue injection port on the lower surface;

[0014] (3) Glue injection: After the gel prepolymer solution in step (1) is drawn up with a syringe (50 mL), it is slowly injected from the glue injection port on the lower surface of the mold in step (2). After the space is filled to 3 / 5-4 / 5, the gel prepolymer solution is slowly injected into the mold until it overflows from the three glue injection holes on the upper surface of the mold;

[0015] (4) Molding of hydrogel respiratory masks: After wiping the gel prepolymer liquid overflowed in step (3), the syringe was immediately removed and the injection port on the lower surface of the mold was sealed with waterproof tape. The mold was then lightly tapped and ultrasonically vibrated for 15-30 minutes to ensure that there were no residual bubbles in the mold. The mold was completely wrapped with plastic wrap and placed in a 30-60°C forced air oven. After reacting for 30-120 minutes, the mold was taken out and placed at room temperature for 30-90 minutes.

[0016] (5) Cutting and packaging of hydrogel respiratory masks: Rinse the mold with cold water for 20 minutes, open the mold, take out the hydrogel respiratory mask, and trim the remaining edges of the hydrogel respiratory mask and the gel injection hole with surgical scissors, or use stamping equipment to quickly cut it to obtain an antibacterial, conductive, special-shaped hydrogel respiratory mask. After disinfection and sterilization, store it in a vacuum sealed bag.

[0017] In the step (1), the mass percentages of the components are: monomer: 25%-55%, conductive ion: 0%-1%, cross-linking agent: 0%-1%, auxiliary agent: 2%-4%, initiator: 0%-1%, catalyst: 0%-1%, deionized water: 37%-73%; wherein the monomer is any two of acrylamide, acrylic acid, sodium acrylate, polyvinyl alcohol, carboxymethyl chitosan, sodium alginate, silk protein, polyamino acid, water-soluble cellulose, agarose, gelatin, carrageenan, or a mixture thereof, or derivative; the conductive ion is any one of potassium salt, sodium salt, lithium salt, and zinc salt; the crosslinking agent is one of N,N'-methylenebisacrylamide, ethylene glycol dimethacrylate, inorganic nanoclay lithium magnesium silicate, β-sodium glycerophosphate, and genipin; the auxiliary agent is any one of a liquid universal compound antibacterial agent, an antioxidant, a moisturizer, and a water-soluble pigment, or a mixture thereof; the initiator is any one of ammonium persulfate or potassium persulfate; and the catalyst is any one of N,N,N',N'-tetramethylethylenediamine or sodium sulfite.

[0018] The respiratory mask plastic mold in step (2) is a 3D printed oral and nasal respiratory mask mold, the mold material of which is acrylic modified alkyd resin, and the respiratory mask is replicated, modeled, and 3D printed light-cured using 3D printing technology and reverse engineering technology.

[0019] The syringe in step (3) is a sterile medical syringe, and the gel prepolymer liquid should be sucked into the syringe slowly and evenly to avoid generating bubbles.

[0020] In step (4), in order to avoid residual bubbles in the mask, the bubbles in the gel prepolymer solution are removed by tapping on the one hand, and ultrasonic vibration is used on the other hand to remove the bubbles. After molding, the mask is left to stand overnight to further remove the bubbles.

[0021] In step (4), in order to increase the strength of the hydrogel respiratory mask, the removed mold can be further immersed in an ionic solution, specifically any one of calcium chloride, calcium lactate, ferric chloride, copper sulfate, and ferrous chloride.

[0022] The disinfection method in step (5) is any one of mechanical moist heat disinfection, acidic oxidative potential water disinfection, and 75% ethanol disinfection. For instruments used directly after moist heat disinfection, the treatment temperature is usually not lower than 90°C, and the treatment time is required to be not less than 2.5 minutes.

[0023] The sterilization treatment method in step (5) is any one of pressure steam sterilization, dry heat sterilization and low temperature sterilization.

[0024] The hydrogel breathing mask is added with carbon nanotubes, graphite, carbon fibers and plasma materials to increase the conductive sensing function, antibacterial property and composite colorful function of the hydrogel breathing mask.

[0025] The mechanical strength of the hydrogel breathing mask can be adjusted by the molar ratio of the monomer and the cross-linking agent, and the reaction speed can be controlled by the monomer concentration, the amount of the initiator and the catalyst, the reaction temperature and time.

[0026] The invention discloses an antibacterial, conductive, special-shaped hydrogel breathing mask, which is characterized by its application in the field of respiratory and medical devices. When used with a ventilator, it can assist and improve respiratory function, increase lung ventilation, and treat chronic obstructive pulmonary disease, respiratory insufficiency, and sleep apnea syndrome.

[0027] Compared with the existing silicone masks on the market, the present invention has the following advantages:

[0028] 1. Simple operation, adjustable reaction speed, mild reaction conditions, no pollution, low cost, and can be mass produced.

[0029] 2. The hydrogel breathing mask of the present invention has strong deformation resistance, extremely high transparency, good elasticity, high toughness, and no burning sensation or pressure.

[0030] 3. The hydrogel respiratory mask of the present invention is universal and can be formed into different types of gel products by designing the mold, and can replace some silicone products.

[0031] 4. Compared with traditional silicone masks, the hydrogel mask of the present invention directly forms a 3D special-shaped structure in one step and has good biocompatibility and biodegradability. It can be widely used in patients with nasal obstruction, dry mouth and nose, and oral air leakage to treat diseases such as chronic obstructive pulmonary disease, respiratory insufficiency, and sleep apnea syndrome.

[0032] 5. The hydrogel breathing mask introduces conductive ions, which can realize functions such as real-time detection of the user's breathing conditions and synchronous data transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Appearance of hydrogel breathing mask;

[0034] Figure 2 Appearance of the hydrogel respiratory mask mold. DETAILED DESCRIPTION

[0035] The present invention is further described below with reference to specific embodiments. The basic principles, main features and advantages of the present invention are shown and described. Those skilled in the art should understand that the present invention is not limited by the following embodiments. The following embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the scope of the present invention and the content of the specification should still fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the attached claims and their equivalents.

[0036] Example 1

[0037] (1) Preparation of gel prepolymer solution: 34 g acrylamide, 1.5 g sodium alginate, 0.03 g potassium chloride, 2 mL glycerol, 500 μL compound antibacterial agent and 0.01 g N, N'-methylenebisacrylamide were added to 50 mL deionized water in sequence, heated at 60°C and stirred for 30 min until a uniform and transparent solution was formed; the mixture was taken out and placed in a 0.1 MPa vacuum box for degassing for 1 h, and 100 μL ammonium persulfate solution (40 wt%) and 20 μL N, N, N', N'-tetramethylethylenediamine (2 wt%) were added to the mixed liquid at room temperature and stirred for 5 min to obtain a gel prepolymer solution;

[0038] (2) Mold assembly: Assemble the upper mold, lower mold, upper flap embedded core, and lower flap embedded core of the 3D printed respiratory mask plastic mold in the order of assembly, seal the boundary gaps of the mold assembly, and leave only three glue injection ports on the upper surface of the mold and one glue injection port on the lower surface;

[0039] (3) Glue injection: After the gel prepolymer solution in step (1) is drawn up with a syringe (50 mL), it is slowly injected from the glue injection port on the lower surface of the mold in step (2). After the space is filled to 3 / 5, the gel prepolymer solution is slowly injected into the mold until it overflows from the three glue injection holes on the upper surface of the mold;

[0040] (4) Respiratory mask molding: After wiping the gel prepolymer liquid overflowed in step (3), the syringe was immediately removed and the injection port on the lower surface of the mold was sealed with waterproof tape. The mold was then lightly tapped and ultrasonically vibrated for 30 minutes to ensure that there were no residual bubbles in the mold. The mold was completely wrapped with plastic wrap and placed in a 60°C blast oven. After reacting for 90 minutes, the mold was taken out and placed at room temperature for 90 minutes, and the mold was immersed in a 110g / mL anhydrous calcium chloride solution for 60 minutes.

[0041] (5) Cutting and packaging of respiratory masks: Rinse the mold with cold deionized water for 20 minutes, open the mold, take out the hydrogel respiratory mask, and trim the remaining edges of the hydrogel respiratory mask and the gel injection hole with surgical scissors to obtain an antibacterial, conductive, special-shaped hydrogel respiratory mask. After 90°C steam wet heat disinfection and pressure steam sterilization, place it in a vacuum sealed bag for storage.

[0042] Example 2

[0043] (1) Preparation of gel prepolymer solution: 35 g acrylamide, 3 g polyvinyl alcohol, 1 g silk protein, 0.05 g sodium chloride, 0.01 g carbon nanotubes and 0.02 g inorganic nanoclay lithium magnesium silicate were added to 50 mL deionized water in sequence, heated at 60°C and stirred for 30 min until a uniform solution was formed; the mixture was taken out and placed in a 0.1 MPa vacuum box for degassing for 1 h, and 100 μL potassium persulfate solution (40 wt%) and 20 μL N, N, N', N'-tetramethylethylenediamine (2 wt%) were added to the mixed liquid at room temperature and stirred for 5 min to obtain gel prepolymer solution A;

[0044] (2) Mold assembly: Assemble the upper mold, lower mold, upper flap embedded core, and lower flap embedded core of the 3D printed respiratory mask plastic mold in the order of assembly, seal the boundary gaps of the mold assembly, and leave only three glue injection ports on the upper surface of the mold and one glue injection port on the lower surface;

[0045] (3) Glue injection: After the gel prepolymer solution in step (1) is drawn up with a syringe (50 mL), it is slowly injected from the glue injection port on the lower surface of the mold in step (2). After the space is filled to 3 / 5, the gel prepolymer solution is slowly injected into the mold until it overflows from the three glue injection holes on the upper surface of the mold;

[0046] (4) Respirator molding: After wiping the overflowed gel prepolymer liquid in step (3), immediately remove the syringe and seal the injection port on the lower surface of the mold with waterproof tape, then gently tap and ultrasonic oscillate the mold for 30 min, after ensuring that there are no residual bubbles in the mold, completely wrap the mold with plastic cling film, and place it in a 60°C air oven, after 90 min of reaction, take out the mold and place it at room temperature for 90 min;

[0047] (5) Respirator cutting and packaging: rinse the mold with cold deionized water for 20 min, open the mold, take out the hydrogel respirator, and use a punching equipment to quickly cut it, thus obtaining an antibacterial, conductive, and special-shaped hydrogel respirator. After steam moist heat sterilization and pressure steam sterilization, it is placed in a vacuum sealed bag for storage.

[0048] Example 3

[0049] (1) Gel prepolymer liquid preparation: 30 g of acrylamide, 0.5 g of agarose, 0.3 g of hydroxyethyl cellulose, 0.01 g of N, N'-methylene bisacrylamide, and 0.02 g of genipin were sequentially added to 50 mL of deionized water, heated to 98°C and stirred for 120 min until a uniform solution was formed; remove and place in a 0.1 MPa vacuum box for 30 min, add 100 μL of potassium persulfate solution (40 wt%) and 400 μL of N, N, N', N'-tetramethyl ethylenediamine (2 wt%) to the mixed liquid at room temperature, stir for 5 min to obtain gel prepolymer liquid A;

[0050] (2) Mold assembly: the upper mold, lower mold, upper petal embedded core and lower petal embedded core of the respirator plastic mold using 3D printing were combined in the order of assembly from top to bottom, the boundary gap of the mold combination was sealed, and only three injection ports on the upper surface of the mold and one injection port on the lower surface were left;

[0051] (3) Injection: the gel prepolymer liquid in step (1) was taken up with a syringe (50 mL), then slowly injected from the injection port on the lower surface of the mold in step (2), and when filled to 3 / 5 of the space, the gel prepolymer liquid was slowly injected into the mold until the three injection ports on the upper surface of the mold overflowed;

[0052] (4) Respirator molding: After wiping the overflowed gel prepolymer liquid in step (3), immediately remove the syringe and seal the injection port on the lower surface of the mold with waterproof tape, then gently tap and ultrasonic oscillate the mold for 30 min, after ensuring that there are no residual bubbles in the mold, completely wrap the mold with plastic cling film, and place it in a 45°C air oven, after 30 min of reaction, take out the mold and place it at room temperature for 90 min;

[0053] (5) Cutting and packaging of respiratory masks: rinse the mold with cold deionized water for 20 minutes, open the mold, take out the hydrogel respiratory mask and quickly cut it using a stamping device to obtain an antibacterial, conductive, special-shaped hydrogel respiratory mask. After 90°C steam wet heat disinfection and pressure steam sterilization, place it in a vacuum sealed bag for storage.

[0054] Example 4

[0055] (1) Preparation of gel prepolymer solution: 25 g acrylamide, 1 g hydroxymethyl chitosan, 0.3 g carrageenan, 0.3 g zinc chloride, 0.02 g graphene oxide and 0.03 g N, N'-methylenebisacrylamide were added to 50 mL deionized water in sequence, heated to 60 ° C and stirred for 60 min until a uniform solution was formed; the mixture was taken out and placed in a 0.1 MPa vacuum box for degassing for 40 min, and 100 μL ammonium persulfate solution (40 wt%) and 400 μL sodium sulfite (2 wt%) were added to the mixed liquid at room temperature and stirred for 5 min to obtain gel prepolymer solution A;

[0056] (2) Mold assembly: Assemble the upper mold, lower mold, upper flap embedded core, and lower flap embedded core of the 3D printed respiratory mask plastic mold in the order of assembly, seal the boundary gaps of the mold assembly, and leave only three glue injection ports on the upper surface of the mold and one glue injection port on the lower surface;

[0057] (3) Glue injection: After the gel prepolymer solution in step (1) is drawn up with a syringe (50 mL), it is slowly injected from the glue injection port on the lower surface of the mold in step (2). After the space is filled to 3 / 5, the gel prepolymer solution is slowly injected into the mold until it overflows from the three glue injection holes on the upper surface of the mold;

[0058] (4) Respiratory mask molding: After wiping the gel prepolymer liquid overflowed in step (3), the syringe was immediately removed and the injection port on the lower surface of the mold was sealed with waterproof tape. The mold was then lightly tapped and ultrasonically vibrated for 30 minutes to ensure that there were no residual bubbles in the mold. The mold was completely wrapped with plastic wrap and placed in a 60°C blast oven. After reacting for 60 minutes, the mold was taken out and placed at room temperature for 90 minutes.

[0059] (5) Cutting and packaging of respiratory masks: rinse the mold with cold deionized water for 20 minutes, open the mold, take out the hydrogel respiratory mask and quickly cut it using a stamping device to obtain an antibacterial, conductive, special-shaped hydrogel respiratory mask. After 90°C steam wet heat disinfection and pressure steam sterilization, place it in a vacuum sealed bag for storage.

Claims

1. A method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask, comprising the following steps: (1) Preparation of gel prepolymer solution: monomers, crosslinking agents, conductive ions and auxiliary agents including any one of a liquid universal compound antibacterial agent, an antioxidant, a moisturizer and a water-soluble pigment or a mixture thereof are sequentially added to deionized water, heated in a water bath to 20-100° C. and stirred for 30-120 min. After a uniform mixed solution is formed, the solution is taken out and placed in a 0.01-1 MPa vacuum box for degassing for 0.5-2 h. Subsequently, the mixed solution is heated in a water bath at 20-100° C. and the diluted initiator and catalyst are sequentially added, and slowly stirred for 5-30 min to obtain a gel prepolymer solution. (2) Mold assembly: Assemble the upper mold, lower mold, upper flap embedded core, and lower flap embedded core of the 3D printed respiratory mask plastic mold in the order of assembly, seal the boundary gaps of the mold assembly, and leave only three glue injection ports on the upper surface of the mold and one glue injection port on the lower surface; (3) Glue injection: After the gel prepolymer solution in step (1) is drawn up with a syringe (50 mL), it is slowly injected from the glue injection port on the lower surface of the mold in step (2). After the space is filled to 3 / 5-4 / 5, the gel prepolymer solution is slowly injected into the mold until it overflows from the three glue injection holes on the upper surface of the mold; (4) Molding of hydrogel respiratory masks: After wiping the gel prepolymer liquid overflowed in step (3), the syringe was immediately removed and the injection port on the lower surface of the mold was sealed with waterproof tape. The mold was then lightly tapped and ultrasonically vibrated for 15-30 minutes to ensure that there were no residual bubbles in the mold. The mold was completely wrapped with plastic wrap and placed in a 30-60°C forced air oven. After reacting for 30-120 minutes, the mold was taken out and placed at room temperature for 30-90 minutes. (5) Cutting and packaging of hydrogel respiratory masks: Rinse the mold with cold water for 20 minutes, open the mold, take out the hydrogel respiratory mask, and trim the remaining edges of the hydrogel respiratory mask and the gel injection hole with surgical scissors, or use stamping equipment to quickly cut it to obtain an antibacterial, conductive, special-shaped hydrogel respiratory mask. After disinfection and sterilization, store it in a vacuum sealed bag.

2. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: In the step (1), the mass percentages of the components are: monomer: 25%-55%, conductive ion: 0%-1%, crosslinking agent: 0%-1%, auxiliary agent: 2%-4%, initiator: 0%-1%, catalyst: 0%-1%, and deionized water: 37%-73%; wherein the monomer is any two of acrylamide, acrylic acid, sodium acrylate, polyvinyl alcohol, carboxymethyl chitosan, sodium alginate, silk protein, polyamino acid, water-soluble cellulose, agarose, gelatin, carrageenan, or a mixture thereof, or a derivative thereof; the conductive ion is any one of potassium salt, sodium salt, lithium salt, and zinc salt; the crosslinking agent is one of N,N'-methylenebisacrylamide, ethylene glycol dimethacrylate, inorganic nanoclay lithium magnesium silicate, sodium β-glycerophosphate, and genipin; the initiator is any one of ammonium persulfate or potassium persulfate; and the catalyst is any one of N,N,N',N'-tetramethylethylenediamine or sodium sulfite.

3. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: The respiratory mask plastic mold in step (2) is a 3D printed oral and nasal respiratory mask mold, the mold material of which is acrylic modified alkyd resin, and the respiratory mask is replicated, modeled, and 3D printed light-cured using 3D printing technology and reverse engineering technology.

4. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: The syringe in step (3) is a sterile medical syringe, and the gel prepolymer liquid should be sucked into the syringe slowly and evenly to avoid generating bubbles.

5. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: In step (4), in order to avoid residual bubbles in the mask, the bubbles in the gel prepolymer solution are removed by tapping on the one hand, and ultrasonic vibration is used to remove the bubbles on the other hand, or the mask is placed at room temperature overnight after injection to further remove the bubbles and form the mask.

6. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: In step (4), in order to increase the strength of the hydrogel respiratory mask, the removed mold can be further immersed in an ionic solution, specifically any one of calcium chloride, calcium lactate, ferric chloride, copper sulfate, and ferrous chloride.

7. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: The disinfection method in step (5) is any one of mechanical moist heat disinfection, acidic oxidative potential water disinfection, and 75% ethanol disinfection. For instruments used directly after moist heat disinfection, the treatment temperature is usually not less than 90°C, and the time is required to be not less than 2.5 minutes. The sterilization treatment method in step (5) is any one of pressure steam sterilization, dry heat sterilization, and low-temperature sterilization.

8. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: The hydrogel breathing mask is added with carbon nanotubes, graphite, carbon fibers and plasma materials to increase the conductive sensing function, antibacterial property and composite colorful function of the hydrogel breathing mask.

9. The method for preparing an antibacterial, conductive, special-shaped hydrogel breathing mask according to claim 1, characterized in that: The mechanical strength of the hydrogel breathing mask can be adjusted by the molar ratio of the monomer and the cross-linking agent, and the reaction speed can be controlled by the monomer concentration, the amount of the initiator and the catalyst, the reaction temperature and time.

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