1. Improper technical operation

Uneven mixing results in poor dispersion, with some exceeding fullness

The high temperature of rubber refining results in an excess of the blending agent

Inaccurate weighing (over weighing, under weighing, missed weighing, incorrect weighing)

The vulcanization temperature is too high, and polymer degradation forms frost spraying

The vulcanization temperature is too low, resulting in incomplete response and the occurrence of insufficient sulfur spray frost

The vulcanization time is not good, resulting in insufficient sulfur spray frost

Improper spraying of release agent or mold washing water results in a whitening appearance on the rubber surface

2. Poor storage conditions

Temperature: The solubility of the compounding agent in rubber usually increases or decreases with the increase of temperature

Time (pressure/humidity): The pressure experienced during rubber storage, the humidity of the surrounding air, and time also have an impact on the solubility of the binder, but usually have little effect. However, if the pressure is high, the compounding agent in the rubber under pressure will form crystal nuclei, which are separated from the surface of the rubber and form frost spraying; If the humidity of the air is too high, the effect of highly polar compounding agents in rubber on non-polar rubber is weakened, the solubility of compounding agents is reduced, and then it leads to frost spraying; The longer the storage time, the more significant the frost on the surface of the rubber, because the temperature and humidity of the air in the storage environment vary with the season, and the differences are significant, which can easily cause changes in the solubility of the blending agent, leading to frost.

3. Rubber aging

Most rubber aging causes damage to the intact and balanced network structure of vulcanized rubber, and also damages the chemical or physical connections between various additives and raw rubber molecules in the rubber system, reducing the solubility of additives in the rubber system. Therefore, those parts of the compound that are in an overly full state will be free to separate from the rubber, forming a spray frost.