Search

CN-121991512-A - Mixing preparation method of high-performance silicone rubber cable material

CN121991512ACN 121991512 ACN121991512 ACN 121991512ACN-121991512-A

Abstract

The invention provides a mixing preparation method of a high-performance silicone rubber cable material, which comprises the steps of mixing 100 parts by weight of methyl vinyl silicone rubber raw rubber with reinforcing filler, flame-retardant filler, a structure control agent and natural astaxanthin serving as antioxidants, and then adding a vulcanizing agent to obtain the high-performance silicone rubber cable material, wherein 50-100 wt% of natural astaxanthin is pre-loaded on silane modified fumed silica to form astaxanthin-loaded modified fumed silica, and the astaxanthin-loaded fumed silica is added in a medium-temperature reinforcing stage. According to the invention, natural astaxanthin is introduced, the super-strong free radical quenching capability is utilized to combine with a carrier storage and release mechanism, so that the high-temperature side methyl oxidation and back biting depolymerization volatilization of the silicone rubber are thoroughly inhibited, meanwhile, the compatible bottleneck is overcome, the mutual embedded double-network synergy of oxidation resistance and reinforcement is formed, the remarkable improvement of heat-resistant temperature, excellent balance of mechanical strength and insulating property is realized, and the novel energy automobile charging pile high-voltage cable is suitable for special high-temperature environments such as new energy automobile charging pile high-voltage cables, aviation wires and the like.

Inventors

  • LI ZHIFAN
  • LI HUA
  • YOU GANHUA

Assignees

  • 江苏优奈特电缆有限公司

Dates

Publication Date
20260508
Application Date
20260210

Claims (9)

  1. 1. The mixing preparation method of the high-performance silicone rubber cable material is characterized by comprising the following steps of: mixing 100 parts of methyl vinyl silicone rubber raw rubber with reinforcing filler, flame-retardant filler, a structure control agent and natural astaxanthin as antioxidants, and then adding a vulcanizing agent to obtain a high-performance silicone rubber cable material; Wherein, 50-100 wt% of natural astaxanthin is pre-loaded on the silane modified fumed silica to form astaxanthin-loaded modified fumed silica, and the astaxanthin-loaded modified fumed silica is added in a medium-temperature reinforcing stage.
  2. 2. The method for preparing the high-performance silicone rubber cable material according to claim 1 is characterized in that the total addition amount of the natural astaxanthin is 1-8 parts by weight, the usage amount of the silane modified fumed silica is 10-20 parts, and the mass ratio of the natural astaxanthin to the silane modified fumed silica is 1:5-10.
  3. 3. The method for preparing the high-performance silicone rubber cable material according to claim 1, wherein the astaxanthin-loaded modified fumed silica is prepared in the following manner: The method comprises the steps of carrying out surface modification on the fumed silica by using a silane coupling agent, then loading natural astaxanthin on the modified fumed silica in a solvent medium, and then drying.
  4. 4. The method for preparing the high-performance silicone rubber cable material according to claim 3, wherein the silane coupling agent is KH-550 or A-171, the amount of the silane coupling agent is 5-20% of the weight of the fumed silica used for load modification, the load process is carried out by ultrasonic dispersion in an ethanol medium for 30-60 minutes, and then vacuum drying is carried out at 50-70 ℃.
  5. 5. The method for preparing the high-performance silicone rubber cable material according to claim 1, wherein the mixing comprises a segmented process: The first stage pre-disperses the structure control agent at 60-80 ℃; Reinforcing at 80-120 ℃ in the second section, and adding astaxanthin-loaded modified fumed silica and residual reinforcing filler; the third section is heat treated at 120-140 ℃ and added with flame retardant filler, and then vacuumized; The fourth stage is open-run at less than 50 ℃ and a vulcanizing agent is added.
  6. 6. The method for preparing the high-performance silicone rubber cable material according to claim 5, wherein the reinforcing filler is fumed silica with a total addition amount of 40-60 parts by weight, and the flame-retardant filler is aluminum hydroxide (particle size of 1-5 μm) pretreated by surface silane with an addition amount of 60-100 parts by weight.
  7. 7. The method for preparing a high-performance silicone rubber cable material according to claim 5, wherein the structure controlling agent comprises 3-8 parts by weight of hexamethyldisilazane, 2-6 parts by weight of diphenyl silicon glycol and 4-8 parts by weight of hydroxyl silicone oil, and further comprises 1-4 parts by weight of iron oxide red as an auxiliary heat-resistant agent, wherein the iron oxide red is added in the second reinforcing stage.
  8. 8. The method for preparing the high-performance silicone rubber cable material according to claim 1, wherein the methyl vinyl silicone rubber raw rubber has a vinyl mole fraction of 0.15-0.25%, the specific surface area of the fumed silica is 200-300m 2 /g, and the vulcanizing agent is 2, 5-dimethyl-2, 5-di (tert-butylperoxy) hexane in an amount of 1.5-2.5 parts by weight.
  9. 9. The use of the silicone rubber cable material obtained by the mixing preparation method of the high-performance silicone rubber cable material according to any one of claims 1-8 in a new energy automobile charging pile high-voltage cable, an electric automobile wire harness or an aviation wire.

Description

Mixing preparation method of high-performance silicone rubber cable material Technical Field The invention belongs to the technical field of high polymer materials, and particularly relates to a mixing preparation method of a high-performance silicone rubber cable material. Background The silicone rubber cable material is based on methyl vinyl silicone rubber raw rubber, is reinforced by white carbon black and flame-retardant by aluminum hydroxide through a gas phase method, and is widely applied to the field of heat-resistant cables. In the prior art, typical schemes (such as CN103524896A, CN102220008A, CN109880375A and the like) mainly depend on inorganic heat-resistant auxiliary agents such as iron oxide red, cerium oxide and the like or conventional structure control agents to delay high-temperature aging, and the auxiliary agents can inhibit lateral methyl oxidation to a certain extent by capturing free radicals or chelating metal ions, but cannot deeply block a free radical chain transmission path at a molecular level, and also cannot effectively inhibit back-biting depolymerization (back-bitingdepolymerization) of a main chain of the silicone rubber at a high temperature, so that low-molecular cyclosiloxane is generated to volatilize, and mass loss is large, cross-linking density is uneven, and performance is fast attenuated. Generally, the long-term heat-resistant temperature of the existing silicone rubber cable material is limited to about 180 ℃, and under the environment (such as the fast-charging peak temperature of a new energy automobile or an aviation high-temperature region) above 200 ℃, the quality loss after aging is remarkable, the mechanical strength is obviously reduced, the insulation performance is deteriorated, and the requirement of the strategically emerging industry on a higher heat-resistant grade is difficult to meet. In addition, in recent years, there have been various studies on the application of natural astaxanthin as a strong antioxidant to natural rubber composites (such as CN108034089a and related documents), the use of conjugated polyolefin double bond structure quenching free radicals to enhance thermo-oxidative aging properties, but these applications are limited to natural rubber systems with carbon-carbon double bond peroxidation, have substantial differences from silicone rubber polysiloxane backbone side methyl oxidation and back biting depolymerization mechanisms, and the prior art does not see any disclosure of astaxanthin application in silicone rubber. More importantly, the astaxanthin is directly introduced to face a compatibility bottleneck that astaxanthin molecules contain polar ketone groups and hydroxyl groups, microphase separation is easy to occur in a nonpolar silicon rubber matrix, so that uneven dispersion, excessive local antioxidant and global deficiency, coloring exudation and competitive adsorption with silanol groups on the surface of white carbon black are caused, thereby weakening a reinforcing interface and affecting mechanical properties and insulation stability. These problems further limit the practical use of potential antioxidants in silicone rubber cable materials. Disclosure of Invention In view of the above, the invention provides a mixing preparation method of a high-performance silicone rubber cable material, which thoroughly solves the problems of high-temperature free radical chain reaction and main chain depolymerization volatilization of the traditional silicone rubber cable material, overcomes the compatibility and dispersion bottleneck of astaxanthin direct addition, and realizes the synergistic quality improvement of heat resistance, mechanical property and insulating property by introducing natural astaxanthin and adopting silane modified fumed silica as a carrier. The technical scheme is that the invention provides a mixing preparation method of a high-performance silicone rubber cable material, which comprises the steps of mixing 100 parts by weight of methyl vinyl silicone rubber raw rubber with reinforcing filler, flame-retardant filler, a structure control agent and natural astaxanthin as antioxidants, and then adding a vulcanizing agent to obtain the high-performance silicone rubber cable material, wherein 50-100 wt% of natural astaxanthin is pre-loaded on silane modified fumed silica to form astaxanthin-loaded modified fumed silica, and the astaxanthin is added in a medium-temperature reinforcing stage. In some embodiments, the total amount of natural astaxanthin added is 1-8 parts, the amount of silane modified fumed silica is 10-20 parts, and the mass ratio of natural astaxanthin to silane modified fumed silica is 1:5-10. The proportion design is based on the super-strong oxidation resistance efficiency of astaxanthin (the singlet oxygen quenching capacity of the astaxanthin is far more than that of a conventional auxiliary agent) and the consideration of load saturation, ensures that the oxidation resistance activ