Structurizing effect of polyethylene and polyisobutylene in oils and greases

1. It has been established that polyethylene, upon swelling in oils, forms plastic structurized systems, while polyisobutylene forms viscous liquids; the thickening effect of polyethylene due to its crystalline structure is substantially greater than that of polyisobutylene. 2. It has been shown that polyisobutylene favors the structurization of lithium, silica gel, and hydrocarbon greases, regardless of the composition of the dispersion medium. The concentration of polymer in silica gel grease prepared with PN-6 oil must be at least 2%, and in the hydrocarbon grease prepared with S-220 oil at least 3%. 3. It has been established that polyisobutylene promotes structurization of lithium and hydrocarbon greases prepared with PN-6 oil, but brings about a softening of the silica gel greases. In the greases prepared with S-220 oil, the addition of polymer (within the concentration range investigated) leads to softening of the greases.