Using atom transfer radical polymerization (ATRP), poly(tert-butyl methacrylate-b-styrene-b-4-vinylpyridine) or PtBMA-b-PS-b-P4VP linear triblock copolymers were synthesized. Different homopolymer and diblock copolymer macroinitiators were used for different block copolymerizations. For a selected triblock copolymer the self-assembly was studied with transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and thermal analysis. Indications were found for a core-shell hexagonal ordering of coaxial cylinders with P4VP cylinders separated from the PtBMA matrix phase by a PS shell layer. To further support this, the interaction parameter between styrene and tBMA was investigated by a random copolymer blend miscibility study on blends of P(S-co-tBMA) random copolymers with PS and found to satisfy 0.08 < chi(S,tBMA) < 0.10.