Nucleating Agents

Nucleating agents (salts of organic acids e.g. sodium benzoate) are added to crystallizable thermoplastic materials, especially polyolefins, polyester, polyamides in order to accelerate crystallization. The change of the crystallization process creates producs with different physical properties.

This term is used for the creation of very small units within a system. During crystallization processes of polymers, polymer crystallites are built up on these substances, which grow and become polymer crystals. In this case the nucleating agent supports the regular dispersion of crystalline zones in amorphous phases, which creates isotropic properties. During the production of foamed polymers very small gas cells are built up on these substances. Nucleating agents are used for the creation of uniform fine foam structures. 

Clarifiers

are a special group of nucleating agents (sorbitoles) which increase the transparency in polypropylene because the spherulitic size of the crystallites gets smaller than the wave length of the light.