On graded S−comultiplication modules

In this paper, we introduce the concept of graded S−comultiplication modules. Several results concerning graded S−comultiplication modules are proved. We show that N is a graded S−second submodule of a graded S−comultiplication R−module M if and only if Ann_R(N) is a graded S−prime ideal of R and there exists x ∈ S such that xN ⊆x- for every x- ∈ S.