In this work, we use dissipative particle dynamics with chemical reactions to study the question of pattern reproduction by a melt of reacting monomers during polycondensation. We show that it is possible to obtain structures with long-range order using this approach of "patterned polycondensation". Depending on the incompatibility parameter chi and reaction rate, three main system morphologies are formed: (a) homogeneous systems without separation; (b) systems with long-range order; (c) systems with tendency to macrophase separation; typical block-lengh distribution for these states are discussed. We show that the region of well-ordered structures moves to the range of higher incompatibility parameter chi and expands upon increasing the reaction rate; possible microscopic explanation of such behavior is proposed. The effect of different film thicknesses and pattern sizes studied. on the structure quality is studied.