Abstract: At present, polyether base oils are generally prepared by ring opening polymerization of epoxides. However, due to the flammable and volatile nature of epoxides, the requirements for safety production are more stringent. In order to solve the above problems, copolyether esters were prepared by polycondensation and decarboxylation of polyethylene glycol, polypropylene glycol and succinic acid with stannous chloride as catalyst. The structure and molecular weight were characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The viscosity-temperature characteristics and lubrication performance of copolyether esters were investigated by using a kinematic viscosity tester, a four-ball friction tester and a 3D white light interferometer. The results showed that the viscosity of the prepared polyether ester was about 170 mm²/s at 40 ℃, the viscosity index was about 220. Under the conditions of 392 N, 30 min and 1 450 r/min, the wear spot diameter of the test steel ball was 0.55 mm, and the average friction coefficient was 0.057. The antifriction effect was significantly better than commercial base oil.

Key words: polyether, polyether ester, viscosity, lubrication performance