Accession Number : AD0819754

Title :   BASIC FACTORS IN THE FORMATION AND STABILITY OF NON-SOAP GREASES FOR HIGH TEMPERATURE APPLICATIONS.

Descriptive Note : Annual rept. 1 Mar 66-28 Feb 67,

Corporate Author : LEHIGH UNIV BETHLEHEM PA INST OF RESEARCH

Personal Author(s) : Zettlemoyer, A. C. ; Micale, F. J.

Report Date : MAR 1967

Pagination or Media Count : 26

Abstract : The percent of the carbon black surface covered with hydrophilic sites was found to vary from 2.4 to 4.4 and was reduced to less than 1% by 1000 C pretreatment. The effect of these hydrophilic groups on the dispersion stability was found to be small in all cases, but the trend was toward a more stable system. The electrokinetic results of Carbolac 1 dispersed in heptanol indicate that the surface groups contribute to formation of the electrical double-layer and hence greater stability is brought about by the coulombic repulsion between particles. A study of the surface properties of Ammeline has revealed that Ammeline is unstable above 150 C. Nitrogen and water adsorption measurements have shown that this temperature treatment results in a decreased surface area. Furthermore, ammonia vapors were detectable after subjecting the Ammeline dispersions to the Shell Roll Test. The penetrometer results for the untreated and 1000 C pretreated Carbolac 1, XC-72 and Shawinigan carbon blacks dispersed in Silicone fluid QF-6-7024, both before and after the Shell Roll Test, are summarized. Gross changes in the degree of flocculation have been observed in the microscope and photographed for Carbolac 1 and low concentrations of XC-72. The results show that the SRT induces flocculation and the system was found to be reversible by again passing the dispersion through the three-roll mill. In all cases observed, a high penetrometer reading resulted in a flocculated system. (Author)

Descriptors :   (*GREASES, THERMAL STABILITY), HEAT RESISTANT MATERIALS, HIGH TEMPERATURE, VAPORS, SILICONES, CARBON, NITROGEN, WATER, TRIAZINES, AMINES, ALCOHOLS, ABSORPTION.

Subject Categories : Lubricants and Hydraulic Fluids

Distribution Statement : APPROVED FOR PUBLIC RELEASE