The mixed rubber is sent to the stock for a period of time, which is called "Parking". Parking is not a simple static process, nor can it be simply understood as the storage stage before the rubber is put into use.

(1) Reduce compound shrinkage

The main material of the compound is an elastomer with high elasticity. They are stretched and pulled by mechanical force in processes such as plastic refining and mixing; Once these external forces disappear, there will be strong elastic recovery (and shrinkage), which is the inherent characteristic of elastomer materials. However, shrinkage is unfavorable to product molding. During parking, shrinkage runs through the whole process. Although the shrinkage process is relatively slow, it is absolutely necessary for molding operation to provide shape and dimensional stability for the compound after parking.

(2) It is conducive to the uniformity and stability of rubber properties

Parking should also be regarded as the process of further uniform dispersion of various compounding agents. Although various compounding agents are dispersed due to the strong mechanical action of the mixer during mixing, due to the limitation of mixing time, And the water contained in the compounding agent itself is agglomerated For objective reasons such as (block), the required degree of dispersion uniformity is often not achieved. In the process of parking, although the external force no longer exists, these powder blocks can continue to disperse with the help of the chain movement of rubber macromolecules to complete the dispersion process that cannot be completed in the mixing process. Although these processes can not be seen by the naked eye, they can be observed by high-power electron microscope before and after parking It can also be proved by performance comparison.