A marine breathing mask body rubber compound and its application

Abstract

The present invention relates to the field of rubber compound technology, and in particular to a kind of marine breathing mask body rubber compound and its application. The object of the present invention is to provide a kind of rubber compound with high vulcanization efficiency, strong tear resistance, aging resistance and non-deformation, which meets the scene use requirements of the mask. The rubber compound comprises the following raw materials in parts by weight: 60 parts of brominated butyl rubber, 40 parts of natural rubber, 8-12 parts of zinc oxide (indirect method), 6.4-9.6 parts of magnesium oxide, 0.5-2.5 parts of accelerator PX, 0.5-2.5 parts of industrial stearic acid, 1.5-3 parts of antioxidant 264, 1.5-3 parts of antioxidant MB, 1.5-3 parts of semi-refined paraffin, 2-5 parts of dioctyl sebacate, 20-50 parts of medium and super wear-resistant furnace black, 5-8 parts of high wear-resistant furnace black, and the mask prepared using the formula of the present invention has the characteristics of good airtightness, fast vulcanization rate, high tear strength, aging resistance and anti-deformation.

Description

Technical Field

[0001] The invention relates to the technical field of rubber compounds, in particular to a rubber compound for a marine breathing mask body and application thereof. Background Art

[0002] During a submarine mission, an accidental fire could cause combustion of internal wiring, fuel, interior decoration, thermal insulation, and other non-metallic materials. This could rapidly deplete the oxygen in the cabin and release a large amount of toxic and hazardous substances, potentially causing suffocation, poisoning, or even death to the crew. In such situations, a supplied-air breathing apparatus (respiratory mask) is required. Quick-connect connectors connect to a compressed air source. This not only isolates the toxic and hazardous substances but also provides the crew with life-sustaining air, buying precious time for escape or awaiting rescue. The mask, as the largest component of the respirator, plays a crucial role in protecting the facial skin. Mask material research plays a central role in respirator material research. During the mask production process, the fabrication of the mask material can significantly impact the final product's appearance and performance. The primary adhesive for the mask material must exhibit excellent airtightness, tear resistance, deformation resistance, aging resistance, and a fast vulcanization rate. The main rubber types used in general-purpose rubber covers are typically butyl rubber and natural rubber. Butyl rubber offers excellent airtightness and tear resistance, but suffers from poor processing properties, such as slow vulcanization, poor adhesion, low solubility in common compounding agents, and poor mixing operability. Natural rubber, on the other hand, offers strong tear and deformation resistance, but suffers from poor airtightness. Furthermore, because natural rubber is a diene rubber, the olefins readily react with oxygen, peroxides, ultraviolet light, and free radicals, making it less resistant to aging. To address these challenges, there is an urgent need to design and develop a rubber compound formula that not only meets the performance requirements of the cover, but also offers a fast vulcanization rate for ease of production and operation. Summary of the Invention

[0003] To solve at least one of the above problems, the present application provides a cover body rubber compound in a first aspect, comprising brominated butyl rubber, natural rubber, zinc oxide, magnesium oxide, an accelerator, stearic acid, an antioxidant, a softener, and a reinforcing agent.

[0004] Among them, the accelerator is PX.

[0005] According to a specific embodiment of the present invention, the cover body compound rubber prepared by the inventor adopts a vulcanization system of ZnO+MgO+PX, and its tear resistance, permanent deformation resistance, and 300% tensile strength are better than other systems. Moreover, because the ZnO+MgO+PX vulcanization system is a sulfur-free vulcanization, the vulcanization efficiency is relatively high and the product's aging resistance is relatively excellent.

[0006] According to a specific embodiment of the present invention, the cover body rubber compound includes, by weight: 60 parts of brominated butyl rubber, 40 parts of natural rubber, 8-12 parts of zinc oxide, 6.4-9.6 parts of magnesium oxide, 0.5-2.5 parts of accelerator, 0.5-2.5 parts of stearic acid, 3-6 parts of antioxidant, 3-8 parts of softener, and 25-40 parts of reinforcing agent.

[0007] According to a specific embodiment of the present invention, the antioxidant includes antioxidant 264 and antioxidant MB, wherein antioxidant 264 accounts for 1-3 parts and antioxidant MB accounts for 1-3 parts.

[0008] According to a specific embodiment of the present invention, the softener includes dioctyl sebacate and semi-paraffin oil, wherein the semi-paraffin oil accounts for 1-4 parts and the dioctyl sebacate accounts for 2-6 parts.

[0009] According to a specific embodiment of the present invention, the reinforcing agent is carbon black.

[0010] According to a specific embodiment of the present invention, the carbon black includes medium-super wear-resistant furnace carbon black and high-wear-resistant furnace carbon black, wherein the medium-super wear-resistant carbon black accounts for 25-30 parts and the high-wear-resistant carbon black accounts for 1-10 parts.

[0011] According to a more specific embodiment of the present invention, the present invention provides a cover body rubber compound, which includes, by mass, 60 parts of chlorinated butyl rubber, 40 parts of natural rubber, 10 parts of zinc oxide (indirect method), 8 parts of magnesium oxide, 1.5 parts of accelerator PX, 1.5 parts of industrial stearic acid, 2 parts of antioxidant 264, 2 parts of antioxidant MB, 2 parts of semi-refined paraffin, 3 parts of dioctyl sebacate, 30 parts of medium and super wear-resistant furnace carbon black, and 7 parts of high wear-resistant furnace carbon black.

[0012] The second aspect of the present invention provides use of the mask body rubber compound described in the first aspect in preparing a marine breathing mask.

[0013] According to a specific embodiment of the present invention, the gas mask prepared with the mask body compound provided by the present invention has better tear resistance, resistance to permanent deformation, 300% tensile strength, and aging resistance than other systems.

[0014] A third aspect of the present invention provides a method for preparing a cover rubber compound, comprising the following steps:

[0015] S1. Adjust the roller temperature of the mixing mill to 50-55°C for the front roller and 45-50°C for the rear roller;

[0016] S2. Adjust the roller distance to 1.0-1.5 mm, add brominated butyl rubber and natural rubber into the open mill, and plasticize and press for 10-15 minutes;

[0017] S3. Add antioxidant 264, antioxidant MB and semi-paraffin oil into the open mill and continue mixing for 5 to 10 minutes;

[0018] S4. Adjust the roller distance to 1.5-3.0 mm, add medium-super wear-resistant furnace carbon black, high wear-resistant furnace carbon black, stearic acid, and dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes;

[0019] S5. Adjust the roller distance to 3.0-4.0 mm, add medium-super wear-resistant furnace carbon black, high wear-resistant furnace carbon black, stearic acid, and dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes;

[0020] S6. Mix the rubber material for 10 to 15 minutes before unloading;

[0021] S7. Adjust the calender roller distance to 1.0-1.5mm and the roller temperature to 30-40℃;

[0022] S8. Add zinc oxide, magnesium oxide, accelerator PX and mixed rubber into the calender, mix them evenly, and cut the sheets after mixing for 8 to 10 minutes. After cutting, isolate the sheets with a pad and place them for 4 to 168 hours to obtain the cover mixed rubber.

[0023] According to a specific embodiment of the present invention, the cover body rubber compound contains, by weight: 60 parts of brominated butyl rubber, 40 parts of natural rubber, 8-12 parts of zinc oxide, 6.4-9.6 parts of magnesium oxide, 0.5-2.5 parts of accelerator PX, 0.5-2.5 parts of stearic acid, 1.5-3 parts of antioxidant 264, 1.5-3 parts of antioxidant MB, 1.5-3 parts of semi-paraffin oil, 2-5 parts of dioctyl sebacate, 20-50 parts of medium and super wear-resistant furnace black, and 5-8 parts of high wear-resistant furnace black.

[0024] According to a more specific embodiment of the present invention, the cover body rubber compound contains, by weight: 60 parts of chlorinated butyl rubber, 40 parts of natural rubber, 10 parts of zinc oxide (indirect method), 8 parts of magnesium oxide, 1.5 parts of accelerator PX, 1.5 parts of industrial stearic acid, 2 parts of antioxidant 264, 2 parts of antioxidant MB, 2 parts of semi-refined paraffin, 3 parts of dioctyl sebacate, 30 parts of medium and super wear-resistant furnace carbon black, and 7 parts of high wear-resistant furnace carbon black.

[0025] A fourth aspect of the present invention provides a gas mask comprising the mask body rubber compound described in the first aspect. DETAILED DESCRIPTION

[0026] The following describes in detail embodiments of the present invention. The examples of the embodiments are intended to explain the present invention but are not to be construed as limiting the present invention.

[0027] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. Furthermore, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0028] In this document, the terms “contain”, “include” or “include” are open expressions, that is, they include the contents specified in the present invention but do not exclude other contents.

[0029] As used herein, the terms "optionally," "optional," or "optionally" generally mean that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0030] In this article, the term "high abrasion furnace black" (HAF) refers to the most commonly used type of hard carbon black. It is produced by the oil furnace process and has a particle size of 26 to 30 nm. It has a specific surface area of ​​80 to 110 m² / g, an oxygen content of 0.5% to 1.0%, a hydrogen content of 0.27% to 0.34%, and a density of approximately 1.8 g / cm³. It is structurally classified into high-strength, standard-strength, and low-strength grades. The tensile strength, tear strength, wear resistance, and aging properties it imparts to rubber products are second only to medium- and super-strength carbon blacks. Its use in tire treads can improve wear resistance and puncture resistance.

[0031] In this article, the term "medium-super wear-resistant carbon black" refers to a major type of hard carbon black produced by the oil furnace process with a particle size of 20-25 nm. Structurally, it can be divided into high-structure, standard-structure, and low-structure derivatives.

[0032] The object of the present invention is to provide a cover body mixed rubber material which can meet the performance requirements of the cover body and has a fast vulcanization rate and is easy to produce and operate.

[0033] The present invention is achieved through the following scheme:

[0034] A cover body rubber compound material, comprising, by weight, 60 parts of bromobutyl rubber, 40 parts of natural rubber, 8-12 parts of zinc oxide, 6.4-9.6 parts of magnesium oxide, 0.5-2.5 parts of an accelerator, 0.5-2.5 parts of stearic acid, 3-6 parts of an antioxidant, 3-8 parts of a softener, and 25-40 parts of a reinforcing agent. The preparation steps are as follows:

[0035] S1. Adjust the roller temperature of the mixing mill to 50-55°C for the front roller and 45-50°C for the rear roller;

[0036] S2. Adjust the roller distance to 1.0-1.5 mm, add the weighed brominated butyl rubber and natural rubber into the open mill, and plasticize and press for 10-15 minutes;

[0037] S3. Add the weighed antioxidant 264, antioxidant MB and semi-paraffin oil into the open mill and continue mixing for 5 to 10 minutes;

[0038] S4. Adjust the roller distance to 1.5-3.0 mm, add 1 / 2 medium-super wear-resistant furnace carbon black, 1 / 2 high-wear-resistant furnace carbon black, 1 / 2 stearic acid, and 1 / 2 dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes;

[0039] S5. Adjust the roller distance to 3.0-4.0 mm, add 1 / 2 medium-super wear-resistant furnace carbon black, 1 / 2 high-wear-resistant furnace carbon black, 1 / 2 stearic acid, and 1 / 2 dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes;

[0040] S6, mix the rubber materials (triangle bag or eight knives) and unload after 10-15 minutes;

[0041] S7. Adjust the calender roller distance to 1.0-1.5mm and the roller temperature to 30-40℃.

[0042] S8. Add the weighed zinc oxide, magnesium oxide, accelerator PX, and rubber mix to the calender. Mix thoroughly using eight knives. Mix for 8-10 minutes before unrolling. Separate the rubber mix with a cloth. To prevent the mix from self-curing, allow the mix to rest for 4 hours before use, but no longer than 7 days.

[0043] In one aspect, the present invention selects a rubber type: a blend of halogenated butyl rubber and natural rubber is used to increase the vulcanization rate, enhance adhesion and solubility in common compounding agents, and improve mixing efficiency. Halogenated butyl rubber is generally divided into two types: chlorobutyl and brominated butyl. Bromobutyl rubber is used as the blended rubber material for the cover because bromine is more active than chlorine, resulting in a relatively fast vulcanization rate. Furthermore, bromine has a low intrinsic purity and is relatively stable when stored in a suitable environment.

[0044] Another aspect of the present invention involves designing a vulcanization system: vulcanization refers to the chemical transformation process by which intersecting linear macromolecular chains form a three-dimensional spatial network structure through chemical crosslinking. The degree of crosslinking of the vulcanized rubber has a significant impact on the physical properties of the vulcanized rubber. Considering the performance of the mask and the characteristics of butyl rubber, the vulcanization system design should focus on the following points:

[0045] a) Increase the vulcanization rate of the rubber compound while avoiding scorch;

[0046] b) Select a vulcanization system with low permanent deformation;

[0047] c) Select a vulcanization system that can increase the modulus by 300%;

[0048] d) Select a vulcanization system with excellent tear resistance;

[0049] e) Select a vulcanization system with strong aging resistance.

[0050] The main reagents and reagent acquisition sources involved in the present invention are shown in Table 1.

[0051] Table 1

[0052]

[0053]

[0054] In this application, the tensile strength, elongation at break, and permanent deformation are determined according to GB / T528-2009 Vulcanized rubber or thermoplastic rubber - Determination of tensile stress-strain properties; the Shore hardness is determined according to GB / T531.1-2008 Vulcanized rubber or thermoplastic rubber - Determination of indentation hardness - Part 1: Shore durometer method (Shore hardness); the tear strength is determined according to GB / T529-2008 Vulcanized rubber or thermoplastic rubber - Determination of tear strength (trouser-shaped, right-angled and crescent-shaped specimens); the anti-fungal ability is determined according to GJB151.10A-2009 Military equipment laboratory environmental test methods - Part 10: Fungal test; hot air aging is determined according to GB / T 3512-2014 Vulcanized rubber or thermoplastic rubber - Hot air accelerated aging and heat resistance test; and the 300% modulus (MPa) is determined according to GB / T528-2009 Vulcanized rubber or thermoplastic rubber - Determination of tensile stress-strain properties.

[0055] It should be noted that the reagents and consumables involved in the present invention can be obtained through conventional purchase, and the asphalts of different penetration degrees of the present invention can also be obtained by those skilled in the art through conventional channels. The following will combine the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0056] Example 1

[0057] This embodiment provides a cover film, and the specific preparation method is as follows:

[0058] 1) Mixing:

[0059] S1. Adjust the roller temperature of the mixing mill to 50-55°C for the front roller and 45-50°C for the rear roller;

[0060] S2. Adjust the roller distance to 1.0-1.5 mm, add 30 kg of brominated butyl rubber and 20 kg of natural rubber to the open mill, and plasticize and press for 10-15 minutes;

[0061] S3. Add 1 kg of antioxidant 264, 1 kg of antioxidant MB, and 1 kg of semi-paraffin oil to the open mill and continue mixing for 5 to 10 minutes;

[0062] S4. Adjust the roller spacing to 1.5-3.0 mm, add 7.5 kg of medium-super wear-resistant furnace carbon black, 1.75 kg of high wear-resistant furnace carbon black, 0.35 kg of stearic acid, and 0.75 kg of dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes;

[0063] S5. Adjust the roller spacing to 3.0-4.0 mm, add 7.5 kg of medium-super wear-resistant furnace carbon black, 1.75 kg of high wear-resistant furnace carbon black, 0.35 kg of stearic acid, and 0.75 kg of dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes;

[0064] S6, mix the rubber materials (triangle bag or eight knives) for 10 to 15 minutes and then cut the materials to obtain BIIR / NR blended rubber;

[0065] 2) Film output:

[0066] S1. Adjust the calender roller distance to 1.0-1.5mm and the roller temperature to 30-40℃.

[0067] S2. Add 5 kg of zinc oxide, 4 kg of magnesium oxide, 0.75 kg of accelerator PX, and the BIIR / NR blend to the calender. Mix thoroughly using eight knives. Mix for 8-10 minutes before unrolling. Separate the sheets with a cloth to obtain the cover mix. To prevent the mix from self-curing, allow the sheets to rest for 4 hours before use, but no longer than 7 days.

[0068] The vulcanization system was designed and tested, and SP1045+ZnO+ZnCl2·2H2O, ZnO+MgO+PX, S (sulfur)+ZnO+TMTD, and S (sulfur)+accelerator DZ+accelerator M were selected and blended with other compounding agents according to the commonly used dosage. The component ratios of each group are as follows:

[0069] 1) BIIR / NR blended rubber: phenolic resin SP1045: zinc oxide: ZnCl2·2H2O=100:10:2.5:1

[0070] 2) BIIR / NR blend rubber: zinc oxide: magnesium oxide: accelerator PX = 100:10:8:0.5

[0071] 3) BIIR / NR blend rubber: sulfur: zinc oxide: accelerator TMTD = 100:2.5:1:0.5

[0072] 4) BIIR / NR blend rubber: sulfur: accelerator DZ: accelerator M = 100:1.5:1:1.

[0073] Among them, 1) is a phenolic resin vulcanization system. SP1045 resin can form stable -C-C- and -C-O-C- crosslinks and has good low permanent deformation. The activator ZnCl2·2H2O can increase the vulcanization rate and improve the properties of the rubber. 2) is a metal oxide vulcanization system. Zinc oxide is used as a vulcanizing agent to give the rubber good heat resistance and ensure flatness during the vulcanization stage. Magnesium oxide improves the scorch resistance of the rubber and increases the storage performance and plasticity of the rubber. Accelerator PX can increase the vulcanization rate. 3) and 4) are sulfur vulcanization systems. In 3), zinc oxide and accelerator TMTD are used, which has a faster vulcanization rate and a shorter scorch time. In 4), accelerators DZ and M are used, which have a relatively fast vulcanization rate, good flatness of the vulcanization curve, a long vulcanization induction period, and good scorch prevention effect.

[0074] The inventors of the present application set up the above four vulcanization systems, combined with BIIR / NR blended rubber, and tested the physical and mechanical properties of the prepared films. The test results are shown in Table 2.

[0075] Table 2 Physical and mechanical properties of films formulated with four vulcanization systems

[0076]

[0077] Table 2 shows that the second vulcanization system, using ZnO+MgO+PX with a BIIR / NR blend, exhibits superior tear strength, permanent deformation, and 300% modulus compared to the other systems. Because the ZnO+MgO+PX vulcanization system is sulfur-free, it offers relatively high vulcanization efficiency and excellent aging resistance.

[0078] The inventors further adjusted the ratio of accelerator PX in the second vulcanization system BIIR / NR blend rubber: accelerator ZnO: accelerator MgO: accelerator PX = 100:10:8:0.5, and obtained the formula ratio with the best performance by testing the physical and mechanical properties of the film, as shown in Table 3.

[0079] Table 3 Physical and mechanical properties of films with different PX ratios

[0080]

[0081] As shown in Table 3, when the PX ratio is 1.5 parts, that is, when the ZnO:MgO:accelerator PX=10:8:1.5, the tear strength, permanent deformation, and 300% modulus of elongation are relatively excellent, and the film has good mechanical properties.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A cover rubber compound, characterized in that: The invention comprises 60 parts of bromobutyl rubber, 40 parts of natural rubber, 8-12 parts of zinc oxide, 6.4-9.6 parts of magnesium oxide, 0.5-2.5 parts of accelerator, 0.5-2.5 parts of stearic acid, 3-6 parts of antioxidant, 3-8 parts of softener and 25-40 parts of reinforcing agent, wherein the accelerator is PX and the vulcanization system adopts ZnO+MgO+PX.

2. The cover rubber compound according to claim 1, characterized in that The antioxidants include antioxidant 264 and antioxidant MB. Among them, antioxidant 264 accounts for 1-3 parts, and antioxidant MB accounts for 1-3 parts.

3. The cover rubber compound according to claim 1, characterized in that The softener includes dioctyl sebacate and semi-paraffin oil. Among them, semi-paraffin oil accounts for 1-4 parts, and dioctyl sebacate accounts for 2-6 parts.

4. The cover rubber compound according to claim 1, wherein: The reinforcing agent is carbon black.

5. The cover rubber compound according to claim 4, characterized in that: The carbon black includes medium-super wear-resistant furnace carbon black and high wear-resistant furnace carbon black. Among them, the medium-super wear-resistant furnace carbon black accounts for 25-30 parts, and the high wear-resistant furnace carbon black accounts for 1-10 parts.

6. Use of the mask body rubber compound according to any one of claims 1 to 5 in the preparation of marine breathing masks.

7. A method for preparing the cover rubber compound according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Adjust the temperature of the mixing mill rollers to 50-55°C for the front roller and 45-50°C for the rear roller. S2. Adjust the roller distance to 1.0-1.5 mm, add the weighed bromobutyl rubber and natural rubber into the open mill, and plasticize and press for 10-15 minutes; S3. Add antioxidant 264, antioxidant MB and semi-paraffin oil into the open mill and continue mixing for 5-10 minutes; S4. Adjust the roller spacing to 1.5-3.0 mm, add part of the super wear-resistant furnace carbon black, high wear-resistant furnace carbon black, stearic acid, and dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes; S5. Adjust the roller distance to 3.0-4.0 mm, add the remaining super wear-resistant furnace carbon black, high wear-resistant furnace carbon black, stearic acid, and dioctyl sebacate into the open mill, and continue mixing for 15-20 minutes; S6, mix the rubber material for 10-15 minutes before unloading; S7. Adjust the calender roller distance to 1.0~1.5mm and the roller temperature to 30~40℃; S8. Add zinc oxide, magnesium oxide, accelerator PX and mixed rubber into the calender, mix them evenly, and take the sheets out after mixing for 8 to 10 minutes. After sheeting, isolate the sheets with a pad and place them for 4 to 168 hours to obtain the cover mixed rubber.

8. The method according to claim 7, characterized in that In parts by weight, the cover body rubber compound contains: 60 parts of brominated butyl rubber, 40 parts of natural rubber, 8-12 parts of zinc oxide, 6.4-9.6 parts of magnesium oxide, 0.5-2.5 parts of accelerator PX, 0.5-2.5 parts of stearic acid, 1.5-3 parts of antioxidant 264, 1.5-3 parts of antioxidant MB, 1.5-3 parts of semi-paraffin oil, 2-5 parts of dioctyl sebacate, 25-30 parts of medium and super wear-resistant furnace carbon black, and 5-8 parts of high wear-resistant furnace carbon black.

9. A gas mask, characterized in that: The invention comprises the cover body compound rubber according to any one of claims 1 to 5.

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