The effect of kaolinite intercalation on the structural arrangements of N-methylformamide and 1-methyl-2-pyrrolidone

N-methylformamide (NMF) and 1-methyl-2-pyrrolidone (NMP) were intercalated with kaolinite, characterized, and deintercalated for analysis (the NMP was intercalated after expansion of the kaolinite layers with NMF). The dynamics of guest molecules within the kaolinite lamellae was studied by means of FT-IR and liquid state H-1 and C-13 NMR on the NMF and NMP before intercalation and also on the deintercalated solutions. Both compounds were deintercalated using water. The FT-IR spectra show no significant differences before and after intercalation, for either NMF or NMP, indicating that there is no change in molecular arrangement as a result of intercalation. H-1 and C-13 NMR investigations supported the findings of the FT-IR and indicated that structural arrangement and orientation of the guest species remain the same after deintercalation. This work provides evidence that intercalation is due to weak physical bonding. (C) 2002 Elsevier Science (USA).