26: High Frequency Transport Properties of Colloidal Dispersions (1988)

Robert John Hunter

Authors

Robert John Hunter School of Chemistry, University of Sydney

Abstract

Liversidge Research Lecture, delivered before the Royal Society of New South Wales, 27th July, 1988. Reproduced by permission of the Royal Society of New South Wales from J. Proc. Roy. Soc. N.S.W., 1988, 121, 165-178.

"Colloidal dspersions occur in a wide range of scientific and technological situations and their proper characterisation is an important area of scientific activity. Almost all colloidal systems are composed of particles which carry a net electrical charge on their surfaces, unless special precautions are taken to remove that charge. Indeed, apart from particle size and shape, electrical charge is probably the most important property determining the behaviour in almost all situations.

"Both the static (equilibrium) and the kinetic charge are normally determined and the two values used to develop a picture of the charge distribution in the region around each particle. That information can then be used to calculate the electrostatic interactions between the particles and hence, to estimate many important aspects of behaviour.

"This paper describes some important new techniques for estimating the magnitude of the charge and its distribution in the neighbourhood of the surface. Important new insights are gained from the study of the conductance and dielectric behaviour at high frequencies (around 1 MHz) and by the study of the interaction of ultrasonic waves and electrical fields at the same frequencies."

Author Biography

Robert John Hunter, School of Chemistry, University of Sydney

Born in rural NSW, Robert (Bob) John Hunter received several bursaries to receive his education, distinguishing himself as early as his first year at New England University College. His first position after university was at the CSIRO at Deiliquin, but soon received a graduate scholarship to the University of Sydney to begin his PhD. After another stint with the CSIRO, Hunter returned to academia, and was eventually the Head of the School of Chemistry at the University of Sydney. His main research area was colloid chemistry; he wrote several books on the subject.

For additional biographical information, photographic permissions, references and a list of honours, awards and publications, please see pages 2–4 of the transcript.