Light-scattering studies on suspensions of orientated attapulgite

摘要: A study is reported of the light scattered by aqueous suspensions clay mineral attapulgite when dispersions were subjected to alternating electric fields. Prior application these fields, conventional measurements indicated that dispersed particles weight average molecular 5·9×109 and 1·1 μm in length. Electron micrographs confirmed approximate cylindrical form particles. The theory for change intensity shape angular scattering diagram fields are applied requirements a suitable apparatus detect changes briefly outlined. observed magnitude up 170 v cm−1 frequencies below 150 Hz characterized an effective permanent dipole moment 4·2×10−6 e.s.u. across electrical anisotropy 2·4×10−13 along rods. latter indicates surface rather than bulk conductivity involved probably synonymous with palygorskite. frequency dependence enabled value rotary diffusion constant 60 s−1 be determined. closed brief comparison between field as used experiments similar but better-known Kerr electro-optical effect.