A twin screw compounding extruder is a single piece of equipment divided into distinct unit operations. Thinking of each unit operation as part of a toolbox can help determine what can be added or improved to process best-quality color masterbatches.
Co-rotating intermeshing twin screw extruders are exceptionally suitable for processing color-pigment masterbatches, offering benefits such as excellent dispersion at high throughput rates, high pigment loading levels, long lifetime of screw and barrel parts, and simple machine operation. That said, processing of color masterbatches comes with its own set of challenges, such as handling of raw ingredients, dispersion of pigments, and cleanliness between color changes.
This article will explore the tools that are available for producing high-quality color masterbatches, as well as techniques to overcome processing challenges while maximizing throughput and product quality.
A twin screw extruder can be considered a “toolbox” providing the operator or process engineer with a highly flexible variety of parts that can be modified and/or moved around to accommodate a specific compounding task. Producing high-quality pigment dispersions is widely proven on twin screw extruders, but not every pigment behaves and processes the same way. The way pigments are handled and how they are treated inside the twin screw extruder is crucial to the performance of the end product.
Firstly, twin screw extruders, even though considered as one piece of equipment, include a dimension of separate unit operations. To understand how to accomplish the best-performing final product, a closer look into each unit operation of the twin screw extruder is crucial.
This article will focus primarily on the split-feed method of masterbatch compounding instead of the premix method, though both are acceptable ways of producing color pigment masterbatches.