A Micrographic Comparison of Greases: STRATCO~R Contactor~(TM) Reactor vs. Kettles

摘要

Regarding simple lithium greases, the micrographs indicate that well developed fiber structures of a similar nature can be produced using all three types of batch reactors. The commercial samples in this study revealed that the autoclave sample was composed of generally thinner fibers than that of the other two methods while the Contactor reactor sample was generally thickest. However, it must be recognized that the variations in processing (e. g., maximum reaction temperature, heating rate, cooling rate, milling/homogenizing, etc.) could affect fiber structure. Consequently, it cannot be assumed that thinner fibers are universally produced in all autoclave processes. It can also be said that greases manufactured on a lab scale seem to be similar to commercial products with respect to structure and properties. Such similarities are evident with significant differences in processing time, both on a commercial scale (3 to 4 hours vs. 5 to 6 hours vs. 8 to 10 hours for Contactor reactor, autoclave and open kettle, respectively) and on a laboratory scale (4 hours vs. 10 hours for Contactor reactor and open kettle). Regarding lithium complex, the micrographs indicated that the autoclave structure was unique, while the commercial greases produced in the Contactor reactor and open kettle appeared similar to each other. The autoclave grease appeared to be formed predominantly of straighter fibers compared to the other two methods, which included more fibers of a spiral nature. The micrographs of the autoclave grease appeared to show a film-like secondary structure, which was not apparent in the other two samples. Although this would be assumed to be related to the complexing agent, the dropping points of the three samples suggest clearly that all were complex greases. Additionally, as with the simple lithium greases, the greases from all three methods indicate the formation of well-developed fiber structures. Also, our samples revealed the Contactor reactor sample to possess generally thicker fibers. The quality of the fiber structure is not diminished by the significant reduction in processing time associated with the Contactor reactor.