https://mts.intechopen.com/articles/show/title/acrylic-polymers-as-additives-for-engine-oil-a-historical-perspectiveOil undergoes temporary viscosity changes under operating conditions in engines. Therefore, engine oils usually contain polymeric additives called viscosity modifiers. These additives are oil soluble polymers; enable the oil to provide adequate hydrodynamic lubrication at high tem…