Understanding dispersion of copper phthalocyanine alpha blue pigment in polyethylene masterbatch with the use of wax

Abstract

Coloured plastics and polymers are widely used in packaging and consumer goods. Despite their critical roles, there is limited literature on detailed analysis of effective pigment dispersion in polymer matrices for masterbatch applications. In this study, detailed research was conducted on pigment dispersion using different wax materials and their performances in polyethylene masterbatches were compared. During the study, it was first found that the presence of salt crystals plays a critical role in dispersion in one of the tested pigments. Using a laser particle size device, it was shown that homogeneous particle size distribution is another critical parameter for proper pigment distribution. Although filter testing is a common method in industrial applications, there is very limited information in the academic literature. The filter test method was used to examine the effects of different polyethylene waxes on pigment dispersion. The best filter pressure values were obtained in masterbatches made with micronised wax. It was also observed that the improved dispersion increased the mechanical properties of the masterbatch. The masterbatch colours were measured with a sphere spectrophotometer and it was observed that uniform pigment distribution increased the colour strengths. Similar results were also seen in polyethylene films produced by the blown film process.

Influence of Compounding Parameters on Color Space and Properties of Thermoplastics with Ultramarine Blue Pigment

“…Polymer coloring entails the synergistic incorporation of colorants and polymers to enhance aesthetics and value-added across diverse applications. A pigment is one of the colorants that is incorporated with thermoplastics in the polymer coloring [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Characterized by their insolubility and solid composition, pigment particles within the polymer matrix exhibit aggregate formations with irregular shapes.…”

“…This leads to the formation of agglomerates during compounding, impacting the subsequent color appearance and performance of thermoplastic coloration [ 1 ]. Hence, a dispersion process is imperative to break down these agglomerates and enhance the wetting of pigments within the polymer matrix [ 1 , 2 , 10 , 11 ].…”

“…Masterbatch technology is an alternative way to overcome dispersion in polymer coloring [ 2 , 12 ]. Masterbatch serves as a practical formulation, combining high concentrations of pigments with a carrier and dispersing agent.…”

“…Material data sheet from the manufacturers (PPCP at 230 • C, 2.16 kg, ABS at 220 • C, 10 kg) 2. Characterize by differential scanning calorimeter from total heat flow 3.…”

“…Residual at 550 • C characterize by thermogravimetric analyzer 2. Opacity measured by spectrophotometer at reflection mode.…”