Application of wax in color masterbatch processing

The addition of PE wax to masterbatch improves the compatibility of the system with the pigment, strengthens the wetting and penetration of the agglomerates, which is beneficial to dispersion. PE wax reduces the viscosity of the system.

The processing and production of color masterbatch need to disperse the pigment agglomerates into primary particles or crystals under the action of shear force to achieve a more uniform primary state. However, after the pigment agglomerates are dispersed, the phenomenon of recondensation will occur under the action of gravitational force. Wax can effectively wet and penetrate into the pores of the agglomerated particles to cover the surface of the pigment and better disperse the pigment agglomerates under the action of shear force to effectively prevent recondensation.

According to the principle of color masterbatch processing, although wax has better wetting and penetration coating effect, however, the low viscosity property of Fischer-Tropsch wax reduces the shear force of the coalescence, which makes the pigment dispersion effect poor. On the contrary, due to its high molecular weight and the presence of branched chain structure, polyethylene wax has a higher viscosity and is more suitable for masterbatch processing.

Polyethylene wax is a low molecular weight polyethylene homopolymer or copolymer that is widely used in coatings. “Wax” means that this polymer is floating in the coating surface in the form of microcrystals playing a similar but more diverse and practical role than paraffin wax. Polyethylene wax is used as a dispersant in masterbatch processing and is widely used in polyolefin masterbatches. It has good compatibility with polyethylene, polyvinyl chloride, polypropylene and other resins, and has very excellent external and internal lubricating effects.