Encapsulants are chemical compound materials used to completely encase a electrical, electronic or other part or assembly. Encapsulants are normally applied..

http://www.engineersedge.com/materials-chemicals-adhesives/encapsulants.htm

Potting compounds are used in electrical and electronics applications to capture or encapsulate the associated device or assembly. Potting compounds maybe used to provide an environmental barrier, dielectric protection and characteristics, thermal conduction path, and structurally enhance a assembly or component. A majority of potting compounds are epoxies..

http://www.engineersedge.com/materials-chemicals-adhesives/potting-compounds.htm