In the extreme conditions of aerospace and deep space exploration, sealing materials must withstand both -70°C and 250°C. Ordinary silicone rubber often suffers from drastic reductions in tensile strength and elongation at break due to low-temperature crystallization hardening or high-temperature degradation. Phenyl raw rubber, with its unique "asymmetric molecular structure" and "thermal-oxidative stabilization mechanism," acts as a "mechanical performance stabilizer" for wide temperature ranges, maintaining its elasticity and strength throughout the dramatic temperature changes from -70°C to 250°C.

The core of phenyl raw rubber's ability to maintain its performance across a wide temperature range lies in its "inhibition of phenyl group crystallization" and "thermal oxidation protection." At low temperatures, ordinary methyl silicone rubber crystallizes and hardens due to the regular arrangement of its molecular chains, losing its elasticity. The large phenyl groups in phenyl raw rubber act as "molecular wedges," inserting between the silicon-oxygen backbone and disrupting the regularity of the molecular chains. This lowers the glass transition temperature (Tg) to below -110℃, ensuring compliant chain segment movement even at -70℃, with a tensile strength retention rate exceeding 90%. At high temperatures, the introduction of phenyl enhances the bond energy of the backbone, and its π-electron cloud forms a conjugation effect with the d orbitals of silicon atoms, increasing the thermal decomposition temperature. Simultaneously, the rigid structure of the phenyl forms a "self-barrier layer" at high temperatures, effectively inhibiting oxygen diffusion into the material, allowing the rubber to retain over 85% of its mechanical properties even after long-term aging in 250℃ hot air.

Furthermore, the excellent "crosslinking network thermal stability" of phenyl raw rubber allows it to maintain the integrity of its network structure during temperature cycling. The active vinyl groups in its molecular chains can form stable chemical bonds with reinforcing fillers. After 1000 thermal cycles from -70℃ to 250℃, the compression set is less than 5%, preventing "permanent collapse" caused by network damage.

From molecular-level crystallization inhibition to macroscopic thermo-oxidative stability, phenyl raw rubber, with its synergistic mechanism of "low-temperature anti-crystallization and high-temperature anti-oxidation," solves the problem of mechanical property degradation of silicone rubber over a wide temperature range. It is not only a key material for sealing in extreme environments but also an invisible guarantee for the reliable operation of high-end equipment across all temperature domains.