Phenyl raw rubber (phenyl silicone rubber) exhibits excellent performance in the application of radiation-resistant cable insulation layers for nuclear submarines. A scientific aging life prediction model enables precise replacement management, ensuring the long-term safe operation of nuclear submarine cable systems in harsh radiation environments.

I. Application Value of Phenyl Raw Rubber in Nuclear Submarine Cable Insulation Layers
Unique Advantages of Phenyl Silicone Rubber:
* The introduction of phenyl groups into the molecular structure disrupts the regularity of the siloxane molecular chains, significantly reducing crystallinity and allowing the material to maintain good elasticity even at extremely low temperatures.
* Outstanding radiation resistance; when the phenyl content is above 30%, the material exhibits excellent radiation resistance, effectively resisting ionizing radiation in the nuclear submarine environment.
* Excellent resistance to heat and oxygen aging; under the combined action of heat and oxygen, phenyl silicone rubber has a longer service life than ordinary silicone rubber, making it particularly suitable for the long-term underwater navigation environment of nuclear submarines.
* Wide temperature adaptability; it can operate stably in environments from -110℃ to 200℃, meeting the dual challenges of the low temperatures of deep-sea nuclear submarines and the high temperatures of equipment.

II. Key Methods for Aging Life Prediction
* 1. Lifetime Assessment Based on Irradiation Trap Model
An irradiation damage model for phenyl silicone rubber was established by measuring the changes in trap density and trap depth with irradiation dose.

Studies show that phenyl silicone rubber can retain 54%-98.7% of its tensile strength after 300 kGy gamma irradiation, depending on the phenyl content and filler type. The composite material with high phenyl content (20%) and the addition of 5 phr Nano-TiO₂ performed best, with a tensile strength retention rate of 98.70% after 300 kGy irradiation.

2. Time-Temperature Equivalence Principle and Arrhenius Model
The time-temperature equivalence principle was applied to convert high-temperature accelerated aging test data into lifetime predictions at actual service temperatures.

The relationship between temperature and aging rate was established using the Arrhenius formula: lnk = lnA - Ea/RT, where k is the reaction rate, A is the frequency factor, Ea is the activation energy, R is the gas constant, and T is the temperature.

For phenyl silicone rubber, three-parameter corrections are required to improve prediction accuracy over a wide temperature range, especially considering temperature fluctuations in the nuclear submarine environment.

3. Accelerated Aging Test Method
This method employs artificial climate accelerated aging testing to simulate the aging process of nuclear submarine cables under a coupled environment of radiation, temperature, and humidity.
Test Parameter Settings:
Irradiation Dose Rate: 0.1-30 Gy/min (simulating the radiation environment of a nuclear submarine)
Temperature Range: -50℃ to 150℃ (covering the low temperatures of deep-sea nuclear submarines and the high temperatures of equipment)
Humidity Control: 10%-95%RH (simulating seawater environments at different depths)
The degradation patterns of key performance indicators (tensile strength, volume resistivity, and elongation at break) are obtained through multi-factor coupled testing.