Alkyl sulfonate modified LDH: Effect of alkyl chain length on intercalation behavior, particle morphology and thermal stability

Mg-Al layered double hydroxide (LDH) was modified with straight-chain primary alkyl sulfonates by regeneration. The effect of alkyl chain length on the intercalation behavior of LDH, particle morphology and thermal stability of the modified LDH were investigated in detail. Irrespective of the chain length, all the alkyl sulfonate was very efficiently intercalated. The alkyl sulfonates usually form monolayers in the interlayer space, except the C18 alkyl sulfonate. The organic modification via regeneration not only changed the primary particle morphology, but at the same time size of alkyl chain significantly influenced the crystal growth during the regeneration. The intercalated alkyl sulfonates decomposed above 300 degrees C and the increasing hydrocarbon chain decreased the decomposition temperature. The alkyl sulfonates stabilized the metal hydroxide layers. (C) 2009 Elsevier B.V. All rights reserved.