Thanks for the question. Since 3M™ introduced 3M™ VHB™ Tape in 1980, we’ve had the ability to do long, real-time studies including a 10 year submersion test. The test report (attached below) shows peel adhesion values after submersing a 3M™ VHB™ Tape for 2 weeks and 10 years in both ordinary tap water and a 5% salt water solution.
Submersed samples were stored in a jar that was maintained at room temperature. After testing in a peel mode, bright clean aluminum/metal surfaces were observed underneath the adhesive bond line. 3M™ VHB™ Tape can act as a barrier that helps protect and prevent galvanic corrosion between dissimilar metallic materials. A combination of adhesive and cohesive failure modes were observed when the bond was broken which indicated very high performance level.
Long term submersion or exposure to moisture or water submersion can have the effect of making the polymer more resilient and tolerant of high elongation. A subsequent lowering in peak force, usually in the order of 40%, is typically measured after many days of exposure. Drying of the 3M™ VHB™ Tape and bond lines will show this effect is reversible, and that the bond will return to the original dry strength.
While we feel that this evaluation is representative of the performance of all 3M™ VHB™ Tapes under continuous submersion underwater, performance to conditions and environments must be thoroughly evaluated by the customer to ensure that any 3M™ VHB™ Tape will meet particular application requirements.