(1) Blending with Weather - Resistant Polymers

• Blending with Fluororubber: Fluororubber has excellent weather resistance, chemical corrosion resistance, and high - temperature resistance. Blending fluororubber with silicone rubber can significantly improve the weather - resistant performance of silicone rubber. The fluorine atoms in the molecular structure of fluororubber have high electronegativity, and the formed C - F bonds have large bond energies, showing strong resistance to external erosion such as ultraviolet rays. In the blending system, the fluororubber phase can be dispersed in the silicone rubber matrix, acting as a physical barrier to reduce the direct contact between ultraviolet rays, oxygen, etc., and silicone rubber molecules. For example, in some outdoor - used seals, using the blended material of silicone rubber and fluororubber can effectively reduce the aging rate of silicone rubber under long - term illumination and harsh environments, extend the service life of the seals, and improve the durability of the sealing performance.
• Blending with Acrylate Rubber: Acrylate rubber has good resistance to high temperature, ozone, and ultraviolet rays. When blended with silicone rubber, acrylate rubber can form a synergistic effect in silicone rubber. The functional groups such as ester groups in its molecular structure can interact with silicone rubber molecules, enhancing the cohesion of the blended material. In outdoor environments, the acrylate rubber part can absorb ultraviolet energy, reducing the degradation degree of silicone rubber molecular chains. At the same time, on the basis of maintaining the good elasticity of silicone rubber, the blending system improves its ozone - aging resistance, making it suitable for application scenarios with high weather - resistance requirements such as automotive door and window seals, and reducing the cracking and hardening of the material caused by ozone erosion.

(2) Blending with Functional Fillers

• Blending with Carbon Nanotubes: Carbon nanotubes have excellent mechanical properties, thermal conductivity, and electrical properties. In terms of improving the weather resistance of silicone rubber, carbon nanotubes mainly play the roles of reinforcement and stress dispersion. Uniformly dispersing carbon nanotubes in silicone rubber to form a three - dimensional network structure can effectively improve the tensile strength and tear resistance of silicone rubber. During the weathering process, when silicone rubber is subjected to external stresses such as ultraviolet irradiation and temperature changes, carbon nanotubes can disperse the stress and prevent the breakage of silicone rubber molecular chains and the propagation of cracks. In addition, carbon nanotubes can also improve the thermal conductivity of silicone rubber to a certain extent, contributing to the uniform distribution of heat and reducing the accelerated aging phenomenon caused by local overheating, thus enhancing the weather - resistant stability of silicone rubber in complex environments.
• Blending with Mica Powder: Mica powder is a flaky mineral filler with good insulation, heat resistance, and chemical stability. After blending with silicone rubber, the flaky structure of mica powder is arranged in parallel in the silicone rubber matrix, forming a physical barrier. This structure can effectively block the penetration of ultraviolet rays, reducing the damage of ultraviolet rays to silicone rubber molecules. At the same time, mica powder can improve the thermal stability of silicone rubber and reduce its thermal degradation rate in high - temperature environments. For example, using the blended material of silicone rubber and mica powder in the insulation seals of some outdoor electrical equipment can enhance the weather resistance and electrical insulation performance of the seals, ensuring the long - term stable operation of the equipment in harsh environments.

II. Improving Weather Resistance through Copolymerization Modification

(1) Copolymerization by Introducing Weather - Resistant Monomers

• Copolymerization with Fluorine - Containing Monomers: Introducing fluorine - containing monomers for copolymerization during the synthesis of silicone rubber is an effective method to improve weather resistance. Fluorine - containing monomers such as trifluoroethyl methacrylate, the fluorine atoms in their molecules endow the polymer segments with excellent weather - resistant properties. After copolymerization, the fluorine - containing segments are distributed in the silicone rubber molecular chain, which not only increases the distance between molecular chains and reduces the interaction between molecular chains but also forms a fluoride - enriched layer with low surface energy on the material surface. This enriched layer can effectively block the erosion of ultraviolet rays, moisture, and chemical substances, improving the weather resistance of silicone rubber. For example, the material prepared by copolymerizing fluorine - containing monomers with silicone rubber monomers still maintains good smoothness and elasticity on its surface after long - term outdoor exposure, and its aging degree is significantly lower than that of ordinary silicone rubber.
• Copolymerization with Benzene - Ring - Containing Monomers: Introducing benzene - ring - containing monomers into the silicone rubber molecular chain can enhance the weather - resistant performance of silicone rubber. The benzene ring has a conjugated structure and can absorb ultraviolet energy, converting it into harmless thermal energy and reducing the damage of ultraviolet rays to the silicone rubber main chain. For example, when copolymerizing monomers containing styryl groups with silicone rubber monomers, in the formed copolymer, the styryl segments can effectively improve the light - aging resistance of silicone rubber. At the same time, the rigid structure of the benzene ring can also enhance the rigidity of the silicone rubber molecular chain, improving the mechanical properties of the material and enabling it to better resist the action of external stresses during the weathering process, maintaining the stability of the structure and performance.