Infrared spectra of kaolin mineral-dimethyl sulfoxide complexes

Abstract--A kaolinite-polymer intercalation complex was apparently formed for the first time by the polymerization of acrylonitrile between the kaolinite layers. A kaolinite-ammonium acetate intercalation complex was dispersed in acrylonitrile monomer. The monomer was apparently incorporated between the layers by displacing intercalated ammonium acetate. After the removal of excess monomer, the intercalation complex was heated to cause polymerization. The resulting kaolinite-polyacrylonitrile (PAN) intercalate showed a basal spacing of ~ 13-14 ~. On heating the complex at 220~ for 1 hr in air, the spacing decreased slightly. The hydrogen bond between the hydroxyls of kaolinite and probably the C---N group of PAN was not affected after heating at 220~ Even after heating at 400~ the layers expanded. Because the starting kaolinite-ammonium acetate intercalation complex decomposed at a much lower temperature, these observations strongly suggest the presence of PAN between the layers.

Section: Sample Preparationmentioning

confidence: 99%

Evidence for the Formation of Interlayer Polyacrylonitrile in Kaolinite

Sugahara

Satokawa

Kuroda

et al. 1988

“…The latter form interlayer hydrogen bondings. Many compounds can intercalate between kaolinite layers; for example, formamides, acetamides, dimethylsulfoxide (S. Olejnik et at 1968Olejnik et at , 1970Costanzo and Giese 1990), fatty acids (Sidheswaren et al 1990), alkali acetates (Costanzo and Giese 1990), and alkali halides (Thompson et al 1992). Intercalation drastically modifies the nature of the interlayer hydrogen bonding, as has been observed in infrared spectroscopy (S. Olejnik et al 1970;Costanzo and Giese 1990;Sidheswaren et al 1990;Thompson et al 1992).…”

Section: Introductionmentioning

confidence: 95%

²H NMR Study of Hydrogen Bonding in Deuterated Kaolinite

Hayashi

1994

Abstract--2H NMR spectra of synthetic deuterated kaolinite have been collected in the temperature range from 150 K to 350 K. Hydroxyl groups show a Pake doublet pattern with an asymmetry factor of 0. They are almost fixed spatially, and undergo a wobbling motion with increasing temperature. The quadrupole coupling constant is 273 +-3 kHz at 150 K, which indicates that interlayer hydrogen bonding is relatively weak.

“…With dimethyl sulphoxide (Weiss et al, 1966;Olejnik et al, 1968;Sanchez Camazano and Gonzalez Garcia, 1966) it was found that the S=O bond was perpendicular to the clay sheets with the oxygen atom 1-8 A from the plane containing the hydroxyl groups, a geometry almost identical to that found for the C = O in formamide. Pyridine N-oxide (Olejnik et al, 1970Weiss and Orth, 1973) also forms an intercalate with kaolinite and the available evidence shows that the molecule has its long axis almost perpendicular to the clay sheets with the oxygen atom at 2.0/~ from the hydroxyl plane.…”

Section: Intercalates With Other Small Moleculesmentioning

confidence: 81%

Unifying Features Relating to the 3D Structures of some Intercalates of Kaolinite

Adams

1978

Abstract--The recent determination of the three-dimensional crystal structure of a dickite:formamide intercalate allows insight into the clay:organic bonding schemes of amides and other small organic molecule intercalates of the kaolin minerals. It is demonstrated that the observed basal spacings of intercalates with these molecules are consistent with hydrogen bonding schemes in which, if possible, triple hydrogen bonds from the clay hydroxyls to ~( are formed. Variations in basal spacing within a series of amides can be explained by considering the maximization of hydrogen bonding while avoiding close van der Waals contacts.