A strategy to obtain chiral silica using an achiral stereoregular polymer with polyhedral oligomeric silsesquioxane (POSS) side chains is described herein. The preferred helical conformation of the POSS-containing polymer could be achieved by mixing isotactic polymethacrylate-functionalized POSS ( it -PMAPOSS) and a chiral dopant. The array structure of POSS molecules, which are placed along the helical conformation, is memorized even after removing the chiral dopant at high temperatures, leading to a chiral silica compound with exclusive optical activity after calcination.

Understanding the physicochemical modulation of functional molecules is the primary step in exploring novel stimuli-responsive materials, and preventing the π−π stacking configuration of π-conjugated molecules has been an effective strategy of vapochromic material development, such as of nanoporous frameworks. Nevertheless, the more complicated synthetic strategy should in fact be applied in many circumstances. In this study, we explore a facile supramolecular strategy where the commodity plastic, syndiotactic-poly(methyl methacrylate) (st-PMMA), is utilized to wrap C 60 to form the inclusion complex. The structural characterization revealed that C 60 s in the st-PMMA supramolecular helix had a lower coordination number (CN = 2) compared to the face-centered-cubic packing of pure C 60 s (CN = 12). Since the st-PMMA/ C 60 helical complex has structural flexibility, the π−π stacking structure of C 60 was further interrupted by the intercalation of toluene vapors, and the complete isolation of C 60 in the complex induced the desired vapochromic behavior. Furthermore, the aromatic interaction between C 60 and aromatic solvent vapors enabled the st-PMMA/C 60 inclusion complex to selectively encapsulate chlorobenzene, toluene, etc., and induce the color change. The st-PMMA/C 60 inclusion complex exhibited a transparent film of sufficient structural integrity such that it can still induce a reversible color change after several cycles. As a result, a new strategy has been discovered for the development of novel vapochromic materials via host−guest chemistry.

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