Various molecular weights of isotactic (it-)-poly(methyl methacrylate) (PMMA) and syndiotactic (st-)-poly(methacrylic acid) (PMAA) were used to form an it-PMMA/st-PMAA (1/2) stereocomplex in acetonitrile/water as a suspension. The stereocomplex was tentatively crosslinked with 1,11-diamino-3-6-9-trioxaundecane and water soluble carbodiimide at 10, 20, and 40 mol % concentrations versus MAA unit. The it-PMMA was extracted from the crosslinked stereocomplex under alkaline conditions, and the successive re-incorporation of the it-PMMA was carried out. During the extraction and re-incorporation processes, the FTIR/ATR spectra showed the absence and generation of a peak at 860 cm-1, respectively, which was characteristic of this stereocomplex. The result of the XRD analysis also corresponded with the extraction and re-incorporation behavior of it-PMMA; peaks were observed at 2 = 12 and 15 degrees, d = 0.74 and 0.59 nm, respectively. This study showed that the nanospaces of helical st-PMAA were available in acetonitrile/water in a suspended state using a crosslinking approach. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012