In the early hours of today, China's manned submersible "Fendouzhe" (Striver) successfully completed its 100th dive to depths exceeding 10,000 meters in the Challenger Deep of the Mariana Trench, setting a new record for the longest continuous underwater operation time in a single mission. The success of this mission is largely attributed to the first full-scale application of a domestically developed "Phenyl-Fluorosilicone Composite Pressure-Resistant Sealing Material." Developed through a joint effort by the Institute of Chemistry, Chinese Academy of Sciences, and leading domestic enterprises, this material is specifically designed for the high pressure (>110 MPa), low temperature (approx. 2°C), and complex chemical environments of the deep sea. According to the on-site technical director, traditional rubber materials are prone to "glass transition" under the extreme pressure of the deep sea, leading to seal failure. The new composite material ingeniously combines the excellent low-temperature resistance and compression set properties of methylphenyl silicone rubber with the superior seawater corrosion and oil resistance of fluorosilicone rubber. During the 12-hour seabed operation, the sealing rings and cable sheaths made from this material maintained zero leakage under a hydrostatic pressure of 115 MPa, with no micro-cracks detected. Even more remarkably, the material integrates self-healing capabilities. When the submersible encountered slight scratches from sharp rocks on the seabed, microcapsules embedded within the material released repair agents to automatically fill the damage, ensuring long-term equipment safety. This breakthrough signifies that China has completely eliminated dependence on imported products in the field of deep-sea extreme environment materials, laying a solid material foundation for the future construction of "Deep Sea Space Stations" and the development of resources at depths of 10,000 meters. The National Deep Sea Center announced that this technology will be expedited for deployment across all deep and far-sea exploration equipment.
Methyl phenyl vinyl silicone rubber IOTA 3120