Search Results

Control of oil viscosity increase at low temperature, which derives from the wax crystallization behaviors of various formulation components, is a critical performance criterion in modern engine oil lubricants. Failure to manage viscosity increase will result in high oil viscosity and poor oil pumpability under cold start conditions, and eventually may lead to catastrophic damage to the engine. The importance of oil low temperature rheology gained further attention when the ILSAC GF-4 specification implemented an aged oil low temperature viscosity limit to guarantee performance retention during operation. This requirement continues in ILSAC GF-5 and is regarded as one of the key benchmarks of modern passenger car engine oils. Pour point depressants (PPDs) are polymeric additives that help alleviate viscosity increase under tcold climate conditions through interaction and control of wax crystallization growth.