1. In a period of time before the extreme value, the thermal curing response of the polymer is not dominant, due to the loose crystallization, the viscosity decreases with the addition of the time. After the extreme value, the crosslinking curing reaction dominates, and the relative molecular weight of the polymer increases rapidly, which increases the viscosity.

2. The relationship between the viscosity of thermosetting plastics and the molding temperature:

When the molding temperature is before the extreme value, the viscosity mainly depends on the physical change of the data, that is, it decreases with the addition of the temperature. After the extreme value, the viscosity is rapidly added due to the predominance of the crosslinking curing reaction. The injection of thermosetting plastics uses this precisely: at temperatures below the extreme point, the data reaches the flow dynamics (low viscosity) in the barrel of the injection machine for injection molding; at temperatures greater than the extreme point, the data Can be cured in the mold cavity.

3. With the addition of the shear rate, the viscosity of the material will decrease, but the activation energy of the crosslinking reaction will decrease due to the frictional heat of the material, and then the reaction rate of the crosslinking curing will be accelerated, and the viscosity of the material will be added quickly.