Clarification mechanisms: how Millad® NX® 8000 works
As the polypropylene crystallizes from the melt, complex macro-structures known as spherulites form. These are responsible for scattering light and their size dictates the polymer’s optical and physical characteristics.
To improve clarity, the spherulite size must be reduced. Insoluble nucleating agents are used, but their effectiveness is limited as the nucleator itself causes a haze and their insolubility leads to non-uniform dispersion.
Millad NX 8000, clarifying agent solubilizes in the molten polypropylene and precipitates from the melt upon cooling, to form a fibrous network whose surface becomes the nucleation site for the PP. This surface creates a very high nucleation density, forming tiny crystallites that are too small to scatter light. The fibers themselves are also too small to scatter light.
Why choose Millad NX 8000?
Traditional clarifiers require a minimum temperature of around 220°C before they will dissolve in PP. At this temperature, the fibrous network is not properly formed, preventing high transparency. Millad NX 8000 has improved solubility characteristics in PP which allow processing at lower temperatures. This creates a broader, more robust processing window and a dramatic improvement in the clarity of polypropylene.