How does VCI compare to desiccants in preventing corrosion?

ZERUST® VCI technology provides active corrosion protection. ZERUST® products release invisible, odorless, non-toxic vapor corrosion inhibitor (“VCI”) molecules. A ZERUST® bag, for example, will actively continue to release VCI molecules until the air inside the bag is completely saturated. The protective ZERUST® VCI molecules will then adsorb themselves to all the surfaces on any metal product(s) inside this bag, forming a transparent, self-repairing, rust protective layer. This nano-layer of corrosion preventative molecules, in turn, actively passivates the metal surfaces and thereby prevents the electrochemical reactions that might otherwise cause rust or corrosion.

Desiccants provide passive corrosion protection. Just like a sponge, desiccants absorb moisture from the surrounding atmosphere. The reduction in ambient humidity can prevent the formation of electrolytes on metal surfaces that might otherwise activate electro-chemical corrosion reactions. However, desiccants have a very finite limit to the maximum amount of water they can absorb. Once this is exceeded, desiccants cease to provide any further protection. Worse, they may even leak moisture back into their surroundings.