Evidence for the Formation of Interlayer Polyacrylonitrile in Kaolinite

Yoshiyuki Sugahara, Shigeo Satokawa, Kazuyuki Kuroda and Chuzo Kato
Department of Applied Chemistry, School of Science and Engineering Waseda University, Ohkubo, Shinjuku-ku, Tokyo, 160, Japan

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 Å. On heating the complex at 220°C 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°C. Even after heating at 400°C, 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.

Key Words: Ammonium acetate • Infrared spectroscopy • Intercalation • Kaolinite • Polyacrylonitrile • Polymerization • X-ray powder diffraction

Clays and Clay Minerals; August 1988 v. 36; no. 4; p. 343-348; DOI: 10.1346/CCMN.1988.0360408
© 1988, The Clay Minerals Society
Clay Minerals Society (www.clays.org)