In　this　paper,　we　develop　a　fully　discrete　scheme　to　solve　the　confined　ternary　blended　polymers　(TBP)　model　with　four　order　parameters　based　on　the　stabilized-scalar　auxiliary　variable　(S-SAV)　approach　in　time　and　the　Fourier　spectral　method　in　space.　Then,　theoretical　analysis　is　given　for　the　scheme　based　on　the　backward　differentiation　formula.　The　unconditional　energy　stability　and　mass　conservation　are　derived.　Rigorous　error　analysis　is　carried　out　to　show　that　the　fully　discrete　scheme　converges　with　order　O(τ2+hm)　in　the　sense　of　the　L2　norm,　where　τ　is　the　time　step,　h　is　the　spatial　step,　and　m　is　the　regularity　of　the　exact　solution.　Finally,　some　numerical　results　are　given　to　demonstrate　the　theoretical　analysis.　Moreover,　the　phase　separation　of　two　kinds　of　polymer　particles,　namely,　Ashura　and　Janus　core-shell　particles,　is　presented　to　show　the　morphological　structures.　©　2022　Global-Science　Press.