Development and Application of Delayed Expansion Rubber for Deep-Sea Environments: Material Properties and Optimal Bonding Techniques

Abstract This study introduces a novel delayed expansion rubber material specifically designed for deep-sea applications, where it can expand after immersion, adapting to the low-temperature and high-pressure conditions of the seabed. The focus of the research is on developing a rubber material with an expansion rate exceeding 200% that retains high strength after expansion, making it suitable for sealing and plugging subsea equipment. The study also explores the optimization of bonding techniques for this material to ensure reliability and durability in field applications. The research began with the formulation and experimental testing of the expansion rubber, aiming to develop a material that delays expansion upon immersion and maintains strength after expansion. Following the validation of material performance, the study investigated bonding techniques for attaching the material to subsea equipment. Two approaches were considered: direct vulcanization for small-sized equipment and adhesive bonding for larger components. Various adhesives were tested, focusing on bonding strength, waterproofing, and durability, with epoxy resin emerging as the preferred bonding agent. Experimental results demonstrated that the delayed expansion rubber exhibits excellent performance in deep-sea environments, with an expansion rate exceeding 200% and high post-expansion strength. The bonding optimization tests revealed that for larger equipment, epoxy resin provides superior bonding strength and waterproofing, making it well-suited for deep-sea applications. Additionally, direct vulcanization was found to be a reliable bonding method for smaller equipment, ensuring strong and durable connections across different sizes of subsea devices. This study successfully developed a delayed expansion rubber material tailored for deep-sea environments and systematically optimized the bonding techniques for its application to subsea equipment. The results indicate that this material and its bonding methods hold significant promise for sealing and plugging in subsea engineering, offering enhanced reliability and durability in harsh deep-sea conditions.