Intercalation of Bulk Guest into LDH via Osmotic Swelling/Restoration Reaction: Control of the Arrangements of Thiacalix[4]arene Anion Intercalates

Water-soluble tetrasodium p -sulfonatothiacalix[4]arene (TCAS) was intercalated into MgAl-LDH using an osmotic swelling/restoration reaction of the LDH in formamide. The restoration process was investigated in detail. The arrangement of TCAS in the interlayer can be controlled through adjusting the area per unit charge ( S charge ) of TCAS. When S charge (TCAS) < S charge (LDH), monolayer (basal spacing, d basal, 1.30 nm) and alternating “up-down” antiparallel ( d basal, 1.54 and 1.45 nm) arrangements were obtained. When S charge of TCAS was increased by forming an Ag + complex, bilayer arrangement ( d basal, 2.12 nm) of TCAS(Ag) was formed. This swelling/restoration reaction took place, and the composites retained the morphology of the LDH precursor. The thermal stability of TCAS in the composites was remarkably enhanced, and the “up-down” antiparallel arrangement of TCAS had the highest increase of thermal stability.