preservative

nouns

a chemical compound that is added to protect against decay or decomposition
is a type of (narrower)
(chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight

adjectives

tending or having the power to preserve
"timbers should be treated with a preservative substance"
is derived from
is derived from
is similar to
intended or adapted to afford protection of some kind
"a protective covering"; "the use of protective masks and equipment"; "protective coatings"; "kept the drunken sailor in protective custody"; "animals with protective coloring"; "protective tariffs"