CN-122011540-A - Hydrogenated nitrile rubber composite material for cryogenic heat preservation and preparation method thereof

CN122011540ACN 122011540 ACN122011540 ACN 122011540ACN-122011540-A

Abstract

The invention discloses a hydrogenated nitrile rubber composite material for cryogenic heat preservation and a preparation method thereof in the field of polymer composite materials, the zirconium-silicon composite modified hydroxyapatite and boron-nitrogen co-doped mesoporous alumina are introduced into the composite material, so that the mechanical property and the heat preservation effect of the material in a low-temperature environment are remarkably improved. The former adopts sol-gel method to construct zirconium silicon oxide network on the surface of hydroxyapatite, and the latter uses alkoxide as precursor to obtain high specific surface area doped mesoporous structure through hydrothermal and calcining. The functional filler is dispersed at a higher temperature before the rubber is mixed, and then the plasticizer is added to ensure the uniform distribution of the filler. The obtained composite material has excellent tensile strength, elongation at break and low heat conductivity coefficient at the temperature of liquid nitrogen, and is suitable for the cryogenic heat preservation fields such as hydrogen energy storage and transportation, aerospace sealing and the like. All raw materials are commercial chemicals, the process is controllable, and the industrial production is easy.

Inventors

ZHAO MIN
LI YAO
LIU HONGLEI
LIU HONGBING
MA YONGQIANG
LIU JIJUN

Assignees

陕西吉美莱新型材料科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260414

Claims (10)

1. The preparation method of the hydrogenated nitrile rubber composite material for deep cooling and heat preservation is characterized by comprising the following steps of: S1, putting 80-120 parts of hydrogenated nitrile rubber into an internal mixer, plasticating at 70-80 ℃, sequentially adding 330-20 parts of carbon black N, 1-2 parts of stearic acid, 3-5 parts of zinc oxide and 4020-2 parts of an anti-aging agent, mixing to obtain a mixture, keeping the temperature of the mixture at 70-90 ℃, firstly adding 3-8 parts of zirconium-silicon composite modified hydroxyapatite and 2-6 parts of boron-nitrogen co-doped mesoporous alumina, mixing, then adding 5-10 parts of dioctyl phthalate, continuing mixing, discharging rubber, cooling to room temperature, and standing to obtain a sizing material; S2, back-refining the sizing material on an open mill, adding 1.5-3.0 parts of dicumyl peroxide and 0.5-1.5 parts of triallyl isocyanurate, discharging after thin-pass to obtain a film, and vulcanizing the film in a flat vulcanizing machine at 165-175 ℃.
2. The method for preparing a hydrogenated nitrile rubber composite material for deep cooling and heat preservation according to claim 1, wherein in the step S1, the time for stopping after the rubber discharge is cooled to room temperature is 24-30 hours.
3. The process for preparing a hydrogenated nitrile rubber composite for cold insulation according to claim 1, wherein in step S2, the vulcanization time is 15 to 20min at 165 to 175 ℃.
4. The method for preparing a hydrogenated nitrile rubber composite material for cryogenic insulation according to claim 1, wherein the method for preparing zirconium-silicon composite modified hydroxyapatite comprises the following steps: 1, dissolving 5-7 parts of zirconium oxychloride and 2-6 parts of tetraethoxysilane in a mixed solution of 30-50 parts of absolute ethyl alcohol, 5-10 parts of deionized water and 10-20 parts of dilute hydrochloric acid in parts by weight, stirring at 60-70 ℃ to obtain zirconium-silicon composite sol, dispersing 8-12 parts of hydroxyapatite powder in 100-150 parts of deionized water, performing ultrasonic treatment to obtain hydroxyapatite suspension, dropwise adding the zirconium-silicon composite sol into the hydroxyapatite suspension under stirring, regulating the pH value to 8.0-9.0 by ammonia water, and continuously reacting at 70-80 ℃ to obtain a reaction mixture; A2, cooling the reaction mixture to room temperature, centrifugally separating to obtain a precipitate, washing the precipitate with deionized water, washing the precipitate with absolute ethyl alcohol, vacuum drying at 100-110 ℃, calcining at 400-500 ℃, grinding and sieving.
5. The process for preparing a hydrogenated nitrile rubber composite for cold insulation according to claim 4, wherein in step A1, the reaction is continued at 70 to 80℃for 4 to 6 hours.
6. The process for preparing a hydrogenated nitrile rubber composite for cryogenic insulation according to claim 4, wherein in step A2, the calcination is performed at 400 to 500℃for a period of 2 to 3 hours.
7. The method for preparing the hydrogenated nitrile rubber composite material for cryogenic insulation according to claim 1, wherein the method for preparing the boron-nitrogen co-doped mesoporous alumina comprises the following steps: According to the weight portion, 15-20 portions of aluminum isopropoxide are dissolved in 100-150 portions of absolute ethyl alcohol, 2-4 portions of hexadecyl trimethyl ammonium bromide are added, stirring is carried out, then 0.6-2 portions of boric acid and 1.5-4 portions of urea are added, stirring is continued to obtain mixed sol, the mixed sol is transferred into a reaction kettle, and hydrothermal reaction is carried out at the temperature of 90-110 ℃ to obtain a reaction mixture; B2, cooling the reaction mixture, filtering to obtain a solid, washing the solid with absolute ethyl alcohol, vacuum drying at 60-80 ℃, placing in a muffle furnace, heating to 500-600 ℃ for calcination, naturally cooling, grinding and sieving.
8. The process for preparing a hydrogenated nitrile rubber composite for cold insulation according to claim 7, wherein in step B1, the hydrothermal reaction is carried out at 90 to 110℃for 18 to 24 hours.
9. The process for preparing a hydrogenated nitrile rubber composite for cryogenic insulation according to claim 7, wherein in step B2, the calcination is performed for 3 to 5 hours at a temperature of 500 to 600 ℃.
10. A hydrogenated nitrile rubber composite for cryogenic insulation, characterized in that it is produced according to the process for producing a hydrogenated nitrile rubber composite for cryogenic insulation according to any one of claims 1 to 9.

Description

Hydrogenated nitrile rubber composite material for cryogenic heat preservation and preparation method thereof Technical Field The invention relates to the technical field of polymer composite materials, in particular to a hydrogenated nitrile rubber composite material for cryogenic heat preservation and a preparation method thereof. Background With the transition of global energy structures to clean low carbon, cryogenic fluids such as liquefied natural gas, liquid hydrogen and the like are increasingly widely applied in the fields of energy storage and transportation, aerospace, superconducting technology and the like, and unprecedented stringent requirements are put on matched sealing and heat insulation materials. The problems of hardening, embrittlement, elastic loss and the like of the traditional rubber material generally exist in an extremely low-temperature environment, and the reliability requirement of long-term service is difficult to meet. The hydrogenated nitrile rubber has excellent oil resistance, heat resistance and higher saturation, and is good under the conventional working condition, but in a cryogenic environment close to the liquid nitrogen temperature, the molecular chain movement is limited, the free volume is reduced, the mechanical property is greatly reduced, and the dual aims of high strength and low heat conduction are difficult to be achieved by a single matrix. Therefore, development of a novel hydrogenated nitrile rubber composite material with high strength and toughness, low heat conductivity and excellent low-temperature stability has become a key technical bottleneck in the field of cryogenic engineering. In order to improve the comprehensive performance of rubber at low temperature, researchers generally adopt a filling modification strategy, and the microstructure and interface interaction of the material are regulated and controlled by introducing inorganic filler. However, although the conventional carbon black or white carbon black can enhance mechanical properties, the heat preservation effect is often weakened due to high heat conductivity, and the partial porous filler can reduce the heat conductivity coefficient, but has poor compatibility with a rubber matrix, and is easy to cause stress concentration, so that the low-temperature elongation at break is insufficient. In recent years, functionalized bioceramics such as hydroxyapatite have been attracting attention due to their low thermal conductivity, good biocompatibility and surface activity, but they lack sufficient chemical stability and interfacial binding capacity, and direct filling is difficult to exert a synergistic effect. Meanwhile, mesoporous alumina has potential in the field of heat insulation by virtue of high specific surface area, adjustable pore structure and low density characteristics, but the surface inertia of the mesoporous alumina limits the interaction with a polymer. If the filler can be subjected to accurate chemical modification to construct a composite system with strong interface bonding, low heat conduction path and nano finite field effect, the ceiling with the performance of the existing material is hopeful to break through. Aiming at the challenges, the prior art attempts to modify the inorganic filler by means of intercalation, cladding or doping, etc., but often faces the problems of unreasonable reaction paths, nonstandard raw materials or uncontrollable process, etc. For example, direct treatment of hydroxyapatite with strong acid tends to cause lattice damage, uniform doping is difficult to achieve when mesoporous alumina is prepared using an insoluble aluminum source, and formation of filler network is severely impaired if plasticizer is added prematurely or the dispersion temperature of functional filler is improper during rubber compounding. Therefore, a technical scheme from filler design to full chain optimization of a composite process is needed, namely, on one hand, a zirconium-silicon composite oxide shell layer is constructed on the surface of hydroxyapatite through a mild and controllable sol-gel method, so that the crystal structure of the zirconium-silicon composite oxide shell layer is protected, the interface compatibility with rubber is enhanced, and on the other hand, a soluble alkoxide is used as a precursor, and a template agent and a co-doping strategy are combined to prepare boron-nitrogen co-doped alumina with an ordered mesoporous structure, so that a heat conduction path is effectively blocked. On the basis, the rubber mixing sequence and temperature are reasonably regulated, the functional filler is ensured to be fully dispersed and not to be interfered by the plasticizer, and finally the high-performance heat-insulating rubber composite material suitable for the deep-cooling extreme environment is obtained. Disclosure of Invention The invention aims to provide a hydrogenated nitrile rubber composite material for cryogenic heat preservation and a prep