What is the difference between water-based and solvent-based sealant; how to choose in application?

Answer 1

A water-based sealant would be some kind of sealant that is dissolved in water -- evaporate the water, and then some air-catalyzed cross-linking occurs.

Solvent-based sealants are dissolved in an organic solvent, and as the solvent evaporates, either air or water vapor causes the cross-linking.

Advantage of the water-based sealant is the lack of organic vapors to stink up the house, disadvantage is that there are some surfaces, such as wood, that they can do as much damage as help. Solvent-based sealants may not damage the wood, but can generate some pretty annoying vapors, and require you to open windows and stuff to air the place out -- not fun on a day when it's 95° and 90% humidity.

If you know what it is you're going to be sealing, check with a rep at the local hardware or home improvement store -- they should be able to match the sealant to the application.

Answer 2

It depends upon the sealing conditions. that means when we have seal a oil tank we generally use water- based sealant like that vice-versa