Preparation of functional domains with a spacing of 10 nm is a benchmark set to fabricate next-generation electronic devices. Organic-inorganic block copolymers form well-ordered microphase separations with very small domain sizes. The design and preparation of a novel block copolymer consisting of syndiotactic polymethyl methacrylate (st-PMMA) and polyhedral oligomeric silsesquioxane (POSS)-functionalized polymethacrylate, designated as st-PMMA-b-PMAPOSS, which can recognize functional molecules, are reported. The st-PMMA segments form a helical structure and encapsulate C-60 in the helical nanocavity, leading to the formation of an inclusion complex. Although the ordering of the domains is not high, C-60 domains that are in a quasi-equilibrium state, with about 10-nm domain spacings, are generated using st-PMMA-b-PMAPOSS that can recognize functional molecules. (c) 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019