SHEAR-STABLE HIGH VISCOSITY POLYALPHAOLEFINS

摘要

A polyalphaolefin polymer, having a kinematic viscosity at 100° C. of 135 cSt or greater, is shear stable. The polymer either has not more than 0.5 wt % of the polymer having a molecular weight of greater than 60,000 Daltons, or after being subjected to twenty hours of taper roller bearing testing, the polymer has a kinematic viscosity loss of less than 9%. Such a shear stable polyalphaolefin is obtained by either mechanical breakdown of a high viscosity polyalphaolefin or by a selective catalyst system used in oligomerization or polymerization of the feedstock.