Laser Light Scattering Measurement of Lubricants at High Pressure and Evaluation of Mechanical Properties (4th Report, Evaluation of High Viscosity of Solidfied Lubricants by Rayleigh Scattering and Photon Correlation Technique)

摘要

A new viscosity measuring system was designed and set up employing Rayleigh light scattering and a photon correlation technique using a diamond-anvil high-pressure cell. Two kinds of experi- ments were attempted. The one was the measurement for dilute suspensions of polystyrene latex spheres in liquid lubricants and a W/O emulsion. Correlation functions induced by Brownian motion of small spheres in the lubricants were observed and the viscosities were obtained whose measure- ment time was one-tenth shorter than that of falling body method. The other experiment was the measurement for 5 P 4 E (polyphenyl ether) and DOP (dioctylphthalate) without mixing polystyrene spheres. Very weak but observable correlation functions concerning structural relaxation were observed and the viscosities of solidified lubricants (about 10~9 Pa·s), obtained in very short time by introducing shift factor for relaxation time, were consistent with those extrapolated from data of falling body method.