Interstratified composite of the anionic clays, Zn5(OH)8(NO3)2∙2H2O and Ni3Zn2(OH)8(NO3)2∙2H2O, by delamination-costacking

• Surfactant-intercalated hydroxysalts delaminate in 1-butanol.
• Layers of two hydroxysalts could be costacked from a mixture of their dispersions.
• The interstratified composite obtained is more stable than zinc hydroxysalt.
• The composite on aging in alkali gives zincate intercalated anionic clay.

The anionic clays zinc hydroxysalt and nickel zinc hydroxy double salt were delaminated in 1-butanol to get monolayer dispersions after interlayer modification with surfactant anion, dodecyl sulfate. When these dispersions were mixed and the mixture treated with excess of acetone, layers from the two clays co-stacked to give a composite in which the layers from the two clays were interstratified. The surfactant anion of the composite could be exchanged with nitrate ions. The nitrate intercalated composite showed increased thermal stability compared to zinc hydroxynitrate. In addition the composite showed improved alkali resistance. When treated with alkaline solution the zinc hydroxysalt layers partially dissolved leading to the formation of a zincate intercalated anionic clay composite.

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