Rubber composite material for high-altitude ice crystal sounding balloon and preparation method thereof

Abstract

This invention relates to the field of polymer materials technology, specifically disclosing a rubber composite material for sounding balloons resistant to high-altitude ice crystals and its preparation method. The rubber composite material for sounding balloons resistant to high-altitude ice crystals comprises the following components: natural rubber, low-temperature resistant rubber, filler, hydrophobic agent, toughening agent, vulcanizing agent, accelerator, antioxidant, activator, and plasticizer; the hydrophobic agent is fluorosilicone oil and silica; the toughening agent includes at least mercaptopropyl-terminated polydimethylsiloxane. This invention has the advantage of simultaneously improving low-temperature toughness and surface hydrophobicity.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, and in particular to a rubber composite material for sounding balloons designed to prevent high-altitude ice crystal formation and its preparation method. Background Technology

[0002] Weather balloons are the core carriers for stratospheric meteorological and space exploration. During operation, they must cope with harsh environments such as extreme low temperatures below -60°C, strong ultraviolet radiation, and low air pressure. Furthermore, the surface of the balloon is prone to ice crystal formation due to supercooled water vapor freezing, which can lead to fatal problems such as substrate puncture and leakage, excessive weight and trajectory deviation, shortened hovering time, and inaccurate detection data. Currently, the mainstream natural rubber-based weather balloon materials can only meet the basic requirements of high elasticity and airtightness. They have core defects such as a sharp drop in low-temperature mechanical properties, lack of anti-icing capability, poor compatibility of anti-icing coatings, and insufficient resistance to ultraviolet aging. Existing technologies cannot simultaneously achieve high elasticity, high airtightness, extreme low-temperature puncture resistance, and long-term anti-icing performance, thus failing to meet the requirements of long-term stratospheric sounding operations.

[0003] Chinese invention patent application number CN202411242317.6 discloses a hydrophobic material and its preparation process, as well as its application in the manufacture of weather balloons. Using acrylate, polyacrylamide, oleamide, and erucamide as core raw materials, a hydrophobic material that can be well integrated with natural latex and chloroprene latex is synthesized through a copolymerization reaction. The material is hydrophobically modified by direct blending with the latex matrix, while simultaneously optimizing the matching vulcanization system, anti-aging system, and plasticizing system. This achieves hydrophobic and anti-icing properties without compromising the core mechanical properties of the balloon matrix. This invention solves the industry pain points of poor adhesion between conventional surface-coated hydrophobic coatings and rubber substrates, and easy cracking and detachment under large deformation. It can significantly reduce the surface tension of balloons, reduce condensation adhesion and ice crystal formation, and reduce the risk of balloon bursting due to ice crystal puncture. It is suitable for hydrophobic and anti-icing modification scenarios for various weather balloons.

[0004] Chinese invention patent ZL202010087735.8 discloses a coating with low icing adhesion performance, its preparation method, and its application. It constructs a dual-structure system of "low-modulus cross-linked elastic network skeleton + migratable free chain interface lubrication," using polyurethane rubber and polysiloxane, which have excellent compatibility with natural rubber, as the elastomer matrix. Through the dual mechanisms of reducing the elastomer modulus and interface lubrication, the adhesion force between the ice layer and the matrix is ​​significantly reduced, allowing ice crystals and ice layers to detach spontaneously under wind force and balloon deformation. This invention solves the industry pain points of easy failure of traditional hydrophobic surface microstructures and easy wear of lubrication layers. The prepared coating has an ice adhesion force as low as below 30 kPa, can expand and contract synchronously with the large deformation of the rubber matrix without cracking or detachment, exhibits excellent wear resistance, and can achieve long-term anti-icing, suitable for low-temperature anti-icing protection scenarios of various elastomer substrates.

[0005] Chinese invention patent ZL201711064245.0 discloses a highly cold-resistant weather balloon and its production method. Using centrifugally concentrated natural latex as the matrix, it introduces oxidized modified polyethylene wax as a cold-resistant agent to reduce the regularity of the vulcanized rubber molecular structure and the intermolecular forces, inhibiting low-temperature crystallization of rubber molecular chains and delaying elastic decay under extreme low-temperature environments. Simultaneously, it incorporates chloroprene polymer, a special antioxidant, and an anti-ozone agent to improve the material's resistance to ultraviolet radiation and ozone aging, and optimizes the uniformity of the balloon's skin thickness to ensure uniform expansion during ascent. This invention solves the problems of a sharp drop in elasticity and puncture resistance of rubber materials used in sounding balloons at extreme low temperatures and rapid decay of mechanical properties after high-altitude irradiation. The resulting weather balloon is suitable for high-altitude sounding needs above 40,000m and maintains excellent low-temperature elongation even at -70℃, making it suitable for long-duration high-altitude sounding operations.

[0006] Chinese invention patent application CN202511403325.9 discloses a high-performance modified natural rubber material for sounding balloons and its preparation method. It innovatively proposes a "particle-aggregated helical conformation long-chain composite crosslinking" design, grafting helical conformation peptides onto the surface of nano-silica cluster particles. Flexible chain extension of rubber molecules is achieved through thiol-double bond click reactions. Relying on the stress-induced conformational extension of peptides and the three-dimensional discrete characteristics of particles, the rubber network achieves three-dimensional large-scale orientation during expansion exceeding 100 times, overcoming the performance contradiction of "strength-multiaxial tensile strength" in traditional reinforcement systems. This invention solves the core bottleneck of conventional carbon black and silica reinforcement systems, which cannot simultaneously achieve both material mechanical strength and multiaxial ultra-high tensile strength. The prepared rubber material can meet the extreme deformation requirements of sounding balloons with volume expansion exceeding 580 times, significantly improving puncture and tear resistance at extreme low temperatures, and is suitable for high-performance modification of rubber materials for high expansion ratio sounding balloons.

[0007] However, current technologies have only achieved single improvements in low-temperature toughness or surface hydrophobicity, failing to simultaneously enhance both. The main challenge lies in the vastly different chemical properties of conventional toughening agents and conventional hydrophobic agents. Toughening agents require polar groups to maintain compatibility with the rubber matrix, while hydrophobic agents require extremely low surface energy, inevitably leading to severe interfacial incompatibility within the system. Polar toughening agents, acting as high-surface-energy "defect points," disrupt the uniformity of the hydrophobic surface, resulting in a decrease in water contact angle, an increase in roll-off angle, and a delay in freezing time. Shortening; at the same time, free small molecule hydrophobic agents weaken the entanglement between rubber molecular chains and form a phase separation structure with toughening agents, making it impossible for toughening agents to effectively void or shear yield, and instead becoming a source of stress concentration. The final result of adding both toughening agents and hydrophobic agents is often "lose-lose", and the hydrophobic properties of the final product are far inferior to those of pure hydrophobic agents. The low-temperature puncture resistance is even lower than that of blank rubber without any additives. However, simply improving low-temperature toughness or surface hydrophobic properties cannot meet the needs of the increasingly extreme operating environment of weather balloons. Therefore, there is still room for improvement. Summary of the Invention

[0008] To simultaneously improve low-temperature toughness and surface hydrophobicity, this application provides a rubber composite material for sounding balloons that are resistant to high-altitude ice crystals and its preparation method.

[0009] In a first aspect, this application provides a rubber composite material for sounding balloons designed to prevent high-altitude ice crystal formation, employing the following technical solution: A rubber composite material for sounding balloons designed to prevent high-altitude ice crystal formation comprises the following components in parts by weight: 70-80 parts natural rubber; 20-30 parts of low-temperature resistant rubber; 18-40 parts of filler; 10-14 parts of hydrophobic agent; 18-22 parts toughening agent; 1-2 parts of vulcanizing agent; Accelerator 1.5-3 parts; Anti-aging agent 4-8 parts; 4-6 parts activator; Plasticizer 4-6 parts; The hydrophobic agent is fluorosilicone oil silica; The toughening agent comprises at least a mercaptopropyl-terminated polydimethylsiloxane.

[0010] By adopting the above technical solution, and specifically selecting mercaptopropyl-terminated polydimethylsiloxane and fluorosilicone oil silica, the mercaptopropyl-terminated polydimethylsiloxane itself has a polysiloxane backbone with extremely low surface energy. Through click chemical reaction between the mercapto groups at both ends and the rubber molecular chain, covalent bonds are added to the cross-linking network. This provides a "liquid spring" toughening mechanism that remains highly flexible below -60℃, without introducing any polar groups that would damage hydrophobicity. This achieves "toughening process is the construction of a hydrophobic substrate". Combined with fluorosilicone oil silica, it provides a micro-nano rough structure and ultra-low surface energy, achieving superhydrophobicity and anti-icing. On the other hand, the nanoparticles themselves reinforce and form a "flexible chain - rigid particle" synergistic reinforcement structure with the PDMS network. Thus, toughening and hydrophobicity are transformed from contradictory to synergistic, ultimately enabling the material to simultaneously possess excellent extreme low-temperature puncture resistance, superhydrophobic anti-icing performance, and high airtightness.

[0011] Preferably, the toughening agent is a combination of mercaptopropyl-terminated polydimethylsiloxane and silicone-based toughening agents.

[0012] By adopting the above technical solution, the addition of silicone-based toughening agents and hydrophobic agents results in better synergy, thus improving the extreme low-temperature puncture resistance and superhydrophobic anti-icing properties.

[0013] Preferably, in the toughening agent, the mass ratio of mercaptopropyl-terminated polydimethylsiloxane to silicone-based toughening agent is 12-13:6-7.

[0014] By adopting the above technical solution and by specifically selecting the mass ratio of mercaptopropyl-terminated polydimethylsiloxane and silicone-based toughening agents, the effect of improving low-temperature toughness is more significant.

[0015] Preferably, the low-temperature resistant rubber is butadiene rubber.

[0016] By adopting the above technical solution and selecting butadiene rubber, the low-temperature toughness of the material can be better improved.

[0017] Preferably, the filler is a compound of hydrophobic fumed silica and alkyl quaternary ammonium salt modified montmorillonite in a mass ratio of 12-32:6-8.

[0018] By adopting the above technical solution and adding fillers composed of hydrophobic fumed silica and alkyl quaternary ammonium salt modified montmorillonite, the reinforcement effect is better, which can significantly improve the tensile strength, tear strength and puncture resistance of the material, and can better improve the airtightness, thus meeting the stringent service requirements of weather balloons under extreme deformation (expansion ratio > 500 times).

[0019] Preferably, the vulcanizing agent is sulfur, and the accelerator is a compound of accelerator CZ, accelerator TMTD and accelerator ZBEC in a mass ratio of 0.5-1:0.5-1:0.5-1.

[0020] By adopting the above technical solutions and selecting specific vulcanization systems, the vulcanization effect is better and the product quality is better.

[0021] Preferably, the antioxidant is a compound of antioxidant 4010NA, antioxidant BHT, ultraviolet absorber UV-531, and hindered amine light stabilizer HALS944 in a mass ratio of 1-2:1-2:1-2:1-2.

[0022] By adopting the above technical solution and adding antioxidant 4010NA, antioxidant BHT, ultraviolet absorber UV-531, and hindered amine light stabilizer HALS944, the aging resistance of the product can be improved in multiple ways, making the product more durable.

[0023] Preferably, the activator is a compound of zinc oxide and stearic acid in a mass ratio of 3-5:1, and the plasticizer is dioctyl sebacate.

[0024] By adopting the above technical solutions, the activation effect of the sulfidation system is better by specifically selecting zinc oxide and stearic acid, and the cold resistance effect is better by specifically selecting dioctyl sebacate, thus improving the processing performance.

[0025] Secondly, this application provides a method for preparing a rubber composite material for sounding balloons designed to prevent high-altitude ice crystal formation, employing the following technical solution: A method for preparing the above-mentioned rubber composite material for high-altitude ice crystal protection sounding balloons includes the following steps: Step 1), plasticize natural rubber and low-temperature resistant rubber at 40-60℃ for 8-15 minutes to obtain plasticized rubber; Step 2) Put the plasticized rubber into the internal mixer, and then add filler, hydrophobic agent, toughening agent, antioxidant, activator and plasticizer to the plasticized rubber. Mix at 70-90℃ for 10-18 minutes. After sheeting, let it stand for 8-24 hours to obtain masterbatch. Step 3) Put the masterbatch into the open mill, then add vulcanizing agent and accelerator to the masterbatch, mix at 40-55℃ for 6-12 minutes, pass through a thin mill 6-10 times, and let it stand for 4-14 hours after sheeting to obtain the compound. Step 4) The compounded rubber is vulcanized and molded to obtain a rubber composite material for weather balloons that are protected against high-altitude ice crystals.

[0026] By adopting the above technical solution, the rubber composite material for sounding balloons that are resistant to high-altitude ice crystals has excellent extreme low-temperature puncture resistance, superhydrophobic anti-icing performance and high air tightness, which well meets the needs of the increasingly extreme operating environment of sounding balloons.

[0027] In summary, this application has the following beneficial effects: 1. Because this application specifically selects mercaptopropyl-terminated polydimethylsiloxane and fluorosilicone oil silica for combination, the mercaptopropyl-terminated polydimethylsiloxane itself has a polysiloxane backbone with extremely low surface energy, and through the click chemical reaction between the mercapto groups at both ends and the rubber molecular chain, covalent bonds are added to the cross-linking network. This provides a "liquid spring" toughening mechanism that remains highly flexible below -60℃, without introducing any polar groups that would damage the hydrophobicity, thus realizing "the toughening process is the construction of a hydrophobic substrate". Combined with fluorosilicone oil silica, on the one hand, it provides a micro-nano rough structure and ultra-low surface energy, achieving superhydrophobicity and anti-icing, and on the other hand, the nanoparticles themselves reinforce and form a "flexible chain - rigid particle" synergistic reinforcement structure with the PDMS network. Thus, toughening and hydrophobicity are transformed from contradictory to synergistic unity, ultimately enabling the material to simultaneously possess excellent extreme low-temperature puncture resistance, superhydrophobic anti-icing performance, and high airtightness.

[0028] 2. In this application, it is preferred to add a filler composed of hydrophobic fumed silica and alkyl quaternary ammonium salt modified montmorillonite, which has a better reinforcing effect, can significantly improve the tensile strength, tear strength and puncture resistance of the material, and can better improve the airtightness, so as to meet the stringent service requirements of weather balloons under extreme deformation (expansion ratio > 500 times).

[0029] 3. In this application, it is preferred to add antioxidant 4010NA, antioxidant BHT, ultraviolet absorber UV-531, and hindered amine light stabilizer HALS944, which can synergistically improve the aging resistance of the product from multiple aspects, making the product more durable. Detailed Implementation

[0030] The present application will be further described in detail below with reference to the embodiments.

[0031] Example 1

[0032] A rubber composite material for sounding balloons protected against high-altitude ice crystals, the preparation method includes the following steps: Step 1): Put 80 kg of natural rubber and 20 kg of butadiene rubber into a mixer, at 40°C and a rotor speed of 35 r / min, and masticate for 8 minutes to obtain masticated rubber.

[0033] Step 2): Put the plasticized rubber into a mixer with a rotor speed of 45 r / min. Then add 3 kg of zinc oxide, 1 kg of stearic acid, 1 kg of antioxidant 4010NA, 1 kg of antioxidant BHT, 1 kg of ultraviolet absorber UV-531, 1 kg of hindered amine light stabilizer HALS944, 12 kg of mercaptopropyl-terminated polydimethylsiloxane, and 6 kg of silicone toughening agent. Mix for 2 min. Then add 12 kg of hydrophobic fumed silica, 6 kg of alkyl quaternary ammonium salt modified montmorillonite, and 10 kg of fluorosilicone oil silica. Mix for 5 min. Finally, add 4 kg of dioctyl sebacate and mix for 3 min. Sheet the mixture and let it stand at room temperature for 8 h to obtain the masterbatch.

[0034] Step 3) Put the masterbatch into the open mill, control the roll temperature at 40℃ and the roll gap at 1mm, then add 1kg sulfur, 0.5kg accelerator CZ, 0.5kg accelerator TMTD and 0.5kg accelerator ZBEC to the masterbatch, mix for 6min, then pass through the thin mill 6 times, sheet out, and let stand at room temperature for 4h to obtain the compound.

[0035] Step 4) Cut and weigh the compounded rubber, put it into the mold, and vulcanize it in a flat vulcanizing machine. The vulcanization temperature is 150℃, the vulcanization pressure is 12MPa, and the vulcanization time is the positive vulcanization time t90=15min. After cooling, a rubber composite material for high-altitude ice crystal sounding balloons with a thickness of 0.1mm is obtained.

[0036] The natural rubber is sourced from commercially available sources; 3L of natural rubber.

[0037] Butadiene rubber is commercially available, BR9000.

[0038] The hydrophobic fumed silica, model CT47, was purchased from Shouguang Changtai New Materials Co., Ltd.

[0039] The alkyl quaternary ammonium salt modified montmorillonite was purchased from Zhejiang Huatai New Materials Co., Ltd., model: DK-1.

[0040] Fluorosilicone oil silica was purchased from Guangzhou Jibisheng Technology Industry Co., Ltd., 8000 mesh.

[0041] The mercaptopropyl-terminated polydimethylsiloxane is commercially available, with CAS number 308072-58-4.

[0042] The silicone-propylene toughening agent was purchased from Dongguan Hongrui Plastic Raw Materials Co., Ltd., model number: USI-3310.

[0043] The sulfur was obtained from commercially available, insoluble sulfur.

[0044] Accelerator CZ is sourced from commercially available products.

[0045] The accelerator TMTD is commercially available.

[0046] The accelerator ZBEC is sourced from commercially available products.

[0047] Anti-aging agent 4010NA is sourced from commercially available products.

[0048] The antioxidant BHT is sourced from commercially available products.

[0049] The ultraviolet absorber UV-531 is sourced from commercially available products.

[0050] The hindered amine light stabilizer HALS944 is commercially available.

[0051] Zinc oxide was purchased from Hebei Kuating New Material Technology Co., Ltd.

[0052] Stearic acid was purchased from Wuhan Xindongyi Chemical Co., Ltd., model: 1838 stearic acid.

[0053] Dioctyl sebacate was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0054] Example 2

[0055] A rubber composite material for sounding balloons protected against high-altitude ice crystals, the preparation method includes the following steps: Step 1): Put 75 kg of natural rubber and 25 kg of butadiene rubber into a mixer, at 50°C and a rotor speed of 40 r / min, and masticate for 12 min to obtain masticated rubber.

[0056] Step 2): Put the plasticized rubber into a mixer with a rotor speed of 50 r / min. Then add 4 kg of zinc oxide, 1 kg of stearic acid, 1.5 kg of antioxidant 4010NA, 1.5 kg of antioxidant BHT, 1 kg of ultraviolet absorber UV-531, 1 kg of hindered amine light stabilizer HALS944, 13 kg of mercaptopropyl-terminated polydimethylsiloxane, and 7 kg of silicone toughening agent. Mix for 3 min. Then add 21 kg of hydrophobic fumed silica, 7 kg of alkyl quaternary ammonium salt modified montmorillonite, and 12 kg of fluorosilicone oil silica. Mix for 6 min. Finally, add 5 kg of dioctyl sebacate and mix for 4 min. Sheet the mixture and let it stand at room temperature for 12 h to obtain the masterbatch.

[0057] Step 3) Put the masterbatch into the open mill, control the roll temperature at 45℃ and the roll gap at 1mm, then add 1.5kg sulfur, 0.75kg accelerator CZ, 0.75kg accelerator TMTD and 0.75kg accelerator ZBEC to the masterbatch, mix for 8 minutes, then pass through the thin mill 8 times, sheet out, and let stand at room temperature for 10 hours to obtain the compound.

[0058] Step 4) Cut and weigh the compounded rubber, put it into the mold, and vulcanize it in a flat vulcanizing machine. The vulcanization temperature is 150℃, the vulcanization pressure is 12MPa, and the vulcanization time is the positive vulcanization time t90=15min. After cooling, a rubber composite material for high-altitude ice crystal sounding balloons with a thickness of 0.1mm is obtained.

[0059] The natural rubber is sourced from commercially available sources; 3L of natural rubber.

[0060] Butadiene rubber is commercially available, BR9000.

[0061] The hydrophobic fumed silica, model CT47, was purchased from Shouguang Changtai New Materials Co., Ltd.

[0062] The alkyl quaternary ammonium salt modified montmorillonite was purchased from Zhejiang Huatai New Materials Co., Ltd., model: DK-1.

[0063] Fluorosilicone oil silica was purchased from Guangzhou Jibisheng Technology Industry Co., Ltd., 8000 mesh.

[0064] The mercaptopropyl-terminated polydimethylsiloxane is commercially available, with CAS number 308072-58-4.

[0065] The silicone-propylene toughening agent was purchased from Dongguan Hongrui Plastic Raw Materials Co., Ltd., model number: USI-3310.

[0066] The sulfur was obtained from commercially available, insoluble sulfur.

[0067] Accelerator CZ is sourced from commercially available products.

[0068] The accelerator TMTD is commercially available.

[0069] The accelerator ZBEC is sourced from commercially available products.

[0070] Anti-aging agent 4010NA is sourced from commercially available products.

[0071] The antioxidant BHT is sourced from commercially available products.

[0072] The ultraviolet absorber UV-531 is sourced from commercially available products.

[0073] The hindered amine light stabilizer HALS944 is commercially available.

[0074] Zinc oxide was purchased from Hebei Kuating New Material Technology Co., Ltd.

[0075] Stearic acid was purchased from Wuhan Xindongyi Chemical Co., Ltd., model: 1838 stearic acid.

[0076] Dioctyl sebacate was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0077] Example 3

[0078] A rubber composite material for use on sounding balloons protected against high-altitude ice crystals, the preparation method includes the following steps: Step 1): Put 70 kg of natural rubber and 30 kg of butadiene rubber into a mixer, at 60°C and a rotor speed of 45 r / min, and masticate for 15 min to obtain masticated rubber.

[0079] Step 2): Put the plasticized rubber into a mixer with a rotor speed of 55 r / min. Then add 5 kg zinc oxide, 1 kg stearic acid, 2 kg antioxidant 4010NA, 2 kg antioxidant BHT, 2 kg ultraviolet absorber UV-531, 2 kg hindered amine light stabilizer HALS944, 14 kg mercaptopropyl-terminated polydimethylsiloxane, and 8 kg silicone toughening agent. Mix for 4 min. Then add 32 kg hydrophobic fumed silica, 8 kg alkyl quaternary ammonium salt modified montmorillonite, and 14 kg fluorosilicone oil silica. Mix for 8 min. Finally, add 6 kg dioctyl sebacate and mix for 6 min. Sheet the mixture and let it stand at room temperature for 24 h to obtain the masterbatch.

[0080] Step 3) Put the masterbatch into the open mill, control the roll temperature at 55℃ and the roll gap at 1mm, then add 2kg sulfur, 1kg accelerator CZ, 1kg accelerator TMTD and 1kg accelerator ZBEC to the masterbatch, mix for 12min, then pass through the thin mill 10 times, sheet out, and let stand at room temperature for 14h to obtain the compound.

[0081] Step 4) Cut and weigh the compounded rubber, put it into the mold, and vulcanize it in a flat vulcanizing machine. The vulcanization temperature is 150℃, the vulcanization pressure is 12MPa, and the vulcanization time is the positive vulcanization time t90=15min. After cooling, a rubber composite material for high-altitude ice crystal sounding balloons with a thickness of 0.1mm is obtained.

[0082] The natural rubber is sourced from commercially available sources; 3L of natural rubber.

[0083] Butadiene rubber is commercially available, BR9000.

[0084] The hydrophobic fumed silica, model CT47, was purchased from Shouguang Changtai New Materials Co., Ltd.

[0085] The alkyl quaternary ammonium salt modified montmorillonite was purchased from Zhejiang Huatai New Materials Co., Ltd., model: DK-1.

[0086] Fluorosilicone oil silica was purchased from Guangzhou Jibisheng Technology Industry Co., Ltd., 8000 mesh.

[0087] The mercaptopropyl-terminated polydimethylsiloxane is commercially available and has the CAS number 308072-58-4.

[0088] The silicone-propylene toughening agent was purchased from Dongguan Hongrui Plastic Raw Materials Co., Ltd., model number: USI-3310.

[0089] The sulfur was obtained from commercially available, insoluble sulfur.

[0090] Accelerator CZ is sourced from commercially available products.

[0091] The accelerator TMTD is commercially available.

[0092] The accelerator ZBEC is sourced from commercially available products.

[0093] Anti-aging agent 4010NA is sourced from commercially available products.

[0094] The antioxidant BHT is sourced from commercially available products.

[0095] The ultraviolet absorber UV-531 is sourced from commercially available products.

[0096] The hindered amine light stabilizer HALS944 is commercially available.

[0097] Zinc oxide was purchased from Hebei Kuating New Material Technology Co., Ltd.

[0098] Stearic acid was purchased from Wuhan Xindongyi Chemical Co., Ltd., model: 1838 stearic acid.

[0099] Dioctyl sebacate was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0100] Comparative Example 1 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Mercaptopropyl-terminated polydimethylsiloxane was used to replace fluorosilicone oil silica in equal amounts.

[0101] Comparative Example 2 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The mercaptopropyl-terminated polydimethylsiloxane was replaced with an equal amount of fluorosilicone oil and silica.

[0102] Comparative Example 3 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Hydrophobic fumed silica was used to replace fluorosilicone oil silica in equal amounts, and mercaptopropyl-terminated polydimethylsiloxane was used to replace mercaptopropyl-terminated polydimethylsiloxane in equal amounts.

[0103] The hydrophobic fumed silica was purchased from Shouguang Changtai New Materials Co., Ltd., model: CT47.

[0104] Comparative Example 4 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The polydimethylsiloxane with mercaptopropyl end caps was replaced with an equal amount of dimethyl silicone oil to replace fluorosilicone silica and mercaptopropyl end caps was replaced with an equal amount of dimethyl silicone oil.

[0105] The dimethyl silicone oil was purchased from Xiamen Jinanhua Industrial Materials Co., Ltd., model: dimethyl silicone oil 201.

[0106] Comparative Example 5 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The fluorosilicone oil and silica were replaced by an equal amount of microcrystalline wax emulsion, and the mercaptopropyl-terminated polydimethylsiloxane was replaced by an equal amount of microcrystalline wax emulsion.

[0107] The microcrystalline wax emulsion was purchased from Shandong Huling New Materials Co., Ltd., model number: WJ-670.

[0108] Comparative Example 6 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The fluorosilicone oil silica was replaced with an equal amount of dioctyl sebacate, and the mercaptopropyl-terminated polydimethylsiloxane was replaced with an equal amount of dioctyl sebacate.

[0109] Dioctyl sebacate was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0110] Comparative Example 7 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Liquid polybutadiene was used to replace fluorosilicone oil silica in equal amounts, and mercaptopropyl-terminated polydimethylsiloxane was used to replace mercaptopropyl-terminated polydimethylsiloxane in equal amounts.

[0111] Liquid polybutadiene was purchased from Shanghai Huanyang Chemical Technology Co., Ltd., Cray Valley Ricon 152.

[0112] Comparative Example 8 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The polydimethylsiloxane with mercaptopropyl end caps was replaced with an equal amount of dioctyl phthalate to replace fluorosilicone oil silica and dioctyl phthalate to replace mercaptopropyl end caps.

[0113] Dioctyl phthalate was purchased from Jinan Zesheng Chemical Co., Ltd.

[0114] Comparative Example 9 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Hydrophobic fumed silica was used to replace fluorosilicone oil silica in equal amounts, and dioctyl sebacate was used to replace mercaptopropyl-terminated polydimethylsiloxane in equal amounts.

[0115] The hydrophobic fumed silica was purchased from Shouguang Changtai New Materials Co., Ltd., model: CT47.

[0116] Dioctyl sebacate was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0117] Comparative Example 10 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Hydrophobic fumed silica was used to replace fluorosilicone oil silica in equal amounts.

[0118] The hydrophobic fumed silica was purchased from Shouguang Changtai New Materials Co., Ltd., model: CT47.

[0119] Comparative Example 11 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The mercaptopropyl-terminated polydimethylsiloxane was replaced with an equal amount of dioctyl sebacate.

[0120] Dioctyl sebacate was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0121] Comparative Example 12 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The polydimethylsiloxane with mercaptopropyl end caps was replaced with an equal amount of dimethyl silicone oil to replace fluorosilicone silica, and with an equal amount of liquid polybutadiene to replace mercaptopropyl end caps.

[0122] The dimethyl silicone oil was purchased from Xiamen Jinanhua Industrial Materials Co., Ltd., model: dimethyl silicone oil 201.

[0123] Liquid polybutadiene was purchased from Shanghai Huanyang Chemical Technology Co., Ltd., Cray Valley Ricon 152.

[0124] Comparative Example 13 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Dimethyl silicone oil was used to replace fluorosilicone oil silica in equal amounts.

[0125] The dimethyl silicone oil was purchased from Xiamen Jinanhua Industrial Materials Co., Ltd., model: dimethyl silicone oil 201.

[0126] Comparative Example 14 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Liquid polybutadiene was used to replace mercaptopropyl-terminated polydimethylsiloxane in equal amounts.

[0127] Liquid polybutadiene was purchased from Shanghai Huanyang Chemical Technology Co., Ltd., Cray Valley Ricon 152.

[0128] Comparative Example 15 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Microcrystalline wax emulsion was used to replace fluorosilicone oil and silica in equal amounts, and dioctyl phthalate was used to replace mercaptopropyl-terminated polydimethylsiloxane in equal amounts.

[0129] The microcrystalline wax emulsion was purchased from Shandong Huling New Materials Co., Ltd., model: WJ-670.

[0130] Dioctyl phthalate was purchased from Jinan Zesheng Chemical Co., Ltd.

[0131] Comparative Example 16 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: Replace fluorosilicone oil and silica with an equal amount of microcrystalline wax emulsion.

[0132] The microcrystalline wax emulsion was purchased from Shandong Huling New Materials Co., Ltd., model: WJ-670.

[0133] Comparative Example 17 A rubber composite material for weather balloons designed to prevent high-altitude ice crystal formation differs from Example 2 only in that: The mercaptopropyl-terminated polydimethylsiloxane was replaced with an equal amount of dioctyl phthalate.

[0134] Dioctyl phthalate was purchased from Jinan Zesheng Chemical Co., Ltd.

[0135] The performance of the rubber composite materials for anti-high-altitude ice crystal sounding balloons prepared in each embodiment and comparative example was tested. The test standards and methods are as follows: 1. Mechanical properties at room temperature: tensile strength and elongation at break are tested according to GB / T 528-2009; tear strength is tested according to GB / T529-2008, test conditions: 23℃.

[0136] 2. Low temperature performance: Using a high and low temperature universal testing machine, after being kept at a low temperature of -60℃ for 30 minutes, the puncture strength (needle tip radius 0.25mm, cone angle 60°, puncture speed 50mm / min) and low temperature breaking elongation of the sample were tested. Test conditions: -60℃.

[0137] 3. Hydrophobic properties: The contact angle and roll-off angle of pure water were tested according to GB / T 30693-2014. The test liquid was 5 μL of deionized water, and the test conditions were 23℃.

[0138] 4. Anti-icing performance: The freezing delay time of 5 μL of deionized water on the sample surface was tested in a constant temperature environment of -20℃; the ice adhesion on the sample surface was tested by the pull-off method. The freezing delay time test conditions were -20℃ and the ice adhesion test conditions were -10℃.

[0139] 5. Air tightness performance: The helium permeability coefficient of the sample was tested according to GB / T 7755-2003. Test conditions: 25℃.

[0140] 6. UV aging resistance: UV aging test for 72h was conducted according to GB / T 16422.3-2014. The tensile strength retention rate of the sample after aging was tested. Test conditions: 60℃.

[0141] The experimental data are detailed in Table 1.

[0142] Table 1

[0143] Table 2

[0144] Table 3

[0145] Table 4

[0146] According to the data comparison in Tables 1-4, the hydrophobic properties and low-temperature toughness of each embodiment are significantly better than those of the comparative examples. The hydrophobic properties of comparative examples 9-17 are lower than those of comparative examples 1, 3, 4, and 5, and the low-temperature toughness of comparative examples 9-17 is lower than that of comparative examples 2, 6, 7, and 8. It can be seen that conventional toughening agents and hydrophobic agents, through simple compounding, not only cannot achieve the effect of simultaneously improving hydrophobic properties and low-temperature toughness, but also have the effect of mutual antagonism, resulting in a toughening effect that is not as good as adding toughening agents alone, and a hydrophobic effect that is not as good as adding hydrophobic agents alone. However, the embodiments, through the compounding of fluorosilicone oil, silica, and mercaptopropyl-terminated polydimethylsiloxane, effectively overcome the defect of large differences in material properties, and achieve a simultaneous improvement in toughening and hydrophobic effects, enabling weather balloons to better meet the needs of increasingly extreme and complex working environments.

[0147] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A rubber composite material for sounding balloons designed to prevent high-altitude ice crystal formation, characterized in that: The components include the following parts by mass: 70-80 parts natural rubber; 20-30 parts of low-temperature resistant rubber; 18-40 parts of filler; 10-14 parts of hydrophobic agent; 18-22 parts toughening agent; 1-2 parts of vulcanizing agent; Accelerator 1.5-3 parts; Anti-aging agent 4-8 parts; 4-6 parts activator; Plasticizer 4-6 parts; The hydrophobic agent is fluorosilicone oil silica; The toughening agent comprises at least a mercaptopropyl-terminated polydimethylsiloxane.

2. The rubber composite material for anti-high-altitude ice crystal sounding balloons according to claim 1, characterized in that: The toughening agent is a combination of mercaptopropyl-terminated polydimethylsiloxane and silicone-based toughening agents.

3. The rubber composite material for anti-high-altitude ice crystal sounding balloons according to claim 2, characterized in that: In the toughening agent, the mass ratio of mercaptopropyl-terminated polydimethylsiloxane to silicone-based toughening agent is 12-13:6-7.

4. The rubber composite material for anti-high-altitude ice crystal sounding balloons according to claim 1, characterized in that: The low-temperature resistant rubber is butadiene rubber.

5. A rubber composite material for high altitude ice crystal sounding balloon according to claim 1, characterized in that: The filler is a compound of hydrophobic fumed silica and alkyl quaternary ammonium salt modified montmorillonite in a mass ratio of 12-32:6-8.

6. A rubber composite material for high altitude ice crystal sounding balloon according to claim 1, characterized in that: The vulcanizing agent is sulfur, and the accelerator is a compound of accelerator CZ, accelerator TMTD and accelerator ZBEC in a mass ratio of 0.5-1:0.5-1:0.5-1.

7. A rubber composite material for high altitude ice crystal sounding balloon according to claim 1, characterized in that: The antioxidant is a compound of antioxidant 4010NA, antioxidant BHT, ultraviolet absorber UV-531, and hindered amine light stabilizer HALS944 in a mass ratio of 1-2:1-2:1-2:1-2.

8. The rubber composite material for anti-high-altitude ice crystal sounding balloons according to claim 1, characterized in that: The activator is composed of zinc oxide and stearic acid in a mass ratio of 3-5:1, and the plasticizer is dioctyl sebacate.

9. A method for preparing a rubber composite material for a weather balloon designed to prevent high-altitude ice crystal formation, as described in any one of claims 1-8, characterized in that: Includes the following steps: Step 1), plasticize natural rubber and low-temperature resistant rubber at 40-60℃ for 8-15 minutes to obtain plasticized rubber; Step 2) Put the plasticized rubber into the internal mixer, and then add filler, hydrophobic agent, toughening agent, antioxidant, activator and plasticizer to the plasticized rubber. Mix at 70-90℃ for 10-18 minutes. After sheeting, let it stand for 8-24 hours to obtain masterbatch. Step 3) Put the masterbatch into the open mill, then add vulcanizing agent and accelerator to the masterbatch, mix at 40-55℃ for 6-12 minutes, pass through a thin mill 6-10 times, and let it stand for 4-14 hours after sheeting to obtain the compound. Step 4) The compounded rubber is vulcanized and molded to obtain a rubber composite material for weather balloons that are protected against high-altitude ice crystals.

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