Microphase separation in polydisperse miktoarm star copolymers

► The miktoarm star copolymer composed of an arbitrary number of types of homopolymers is considered. ► The procedure is proposed for finding the Landau free energy of this copolymer melt. ► The phase diagrams have been obtained for AB2 miktoarm star melt with polydisperse A-block. ► The temperature of the order-disorder transition increases as polydispersity index grows.