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The relationship between the dynamic viscosity of polymers and temperature follows the Arrhenius equation: n= ’’. -uKwhere‘. is the proportionality constant, which is related to the free volume and varies with temperature. AU represents the activation energy required for a polymer chain segment to move from its original position to a vacant site. The equation shows that at high temperatures, the viscosity of the solution decreases exponentially as the temperature rises, and the extent of this decrease depends on its structure. In the study of kinematic viscosity properties, it was found that the kinematic viscosity of liquids with lower molecular weights (such as oils) does not conform to the Arrhenius equation. For brake fluid used in vehicles, national standards require that its viscosity at 100°C be no less than 1.5 centipoise, and its viscosity at -40°C be no more than 1800 centipoise. Due to the stringent requirements under low temperatures (-40°C) and high temperatures (100°C), it is difficult to measure the viscosity of brake fluid. Therefore, identifying the relationship between the fluid’s dynamic viscosity and temperature is of great theoretical significance for calculating its viscosity under such extreme conditions, and it also holds practical value for testing the performance of brake fluid. However, there is little systematic research in this area, and few available resources, making it a relatively novel topic. In this experiment, the kinematic viscosity of oils was determined using the capillary method. Based on Poiseuille’s equation, a formula for determining the kinematic viscosity of liquids was derived: V = C × r, where V represents the kinematic viscosity (centimeters per second), C is a constant (centimeters per second per unit time), and r is the time required for the liquid to flow through a certain volume (seconds). By knowing the value of the constant C and measuring the time it takes for the liquid to flow through a certain volume, the viscosity of the liquid can be calculated, thereby determining how the kinematic viscosity changes with temperature.