What are the disadvantages of traditional brake fluid?

Currently, there are three main categories of synthetic brake fluids: alcohol ether type, ester type and silicone oil type.

Among them, ester type brake fluid is divided into carboxylate type and alcohol ether borate type brake fluid.

Silicone oil brake fluid is divided into silicone type and silicone grease type brake fluid.

①Alcohol ether type brake fluid.

The main component is polyoxyethylene ether compounds, which are mixed with lubricants, diluents, anti-rust agents, rubber inhibitors, etc. It is the most common brake fluid used in cars in various countries, and most products are DOT3 grade.

, a few can reach DOT4 level.

This brake fluid has the advantages of a high equilibrium reflux boiling point, low low-temperature viscosity, good rubber adaptability, and low corrosion to metals.

The disadvantage is that alcohol ether type brake fluid easily absorbs moisture in the air and generates boiling substances with lower boiling points, resulting in reduced high-temperature performance: at the same time, after absorbing moisture, as the water content increases, the low-temperature viscosity will increase significantly, thus

reduce its low temperature performance.

In addition, the entry of water will increase the corrosiveness of the brake fluid and accelerate the corrosion of metal materials in the braking system.

②Alcohol ether borate ester brake fluid.

In order to increase the equilibrium reflux boiling point and reduce hygroscopicity, research has found that ester brake fluids can meet the above requirements. In particular, boric acid esterification of polyethylene glycol ethers can significantly reduce the impact of water on the boiling point of alcohol ether brake fluids.

This type of brake fluid is generally divided into three levels: DOT4, super DOT4 (V4) and DOT5.1.