In masterbatch formulations, dispersants, compatibilizers, and processing aids are commonly used to improve dispersion of additives and overall performance of the masterbatch. Here are some typical additives in each category:
Dispersants
Surfactants
Surfactants are compounds that can reduce surface tension and improve wetting of particles in the polymer matrix. They help disperse additives such as pigments, fillers, and other functional additives.
Polymeric Dispersants
These are specially designed polymers with functional groups that can interact with both the polymer matrix and the dispersed particles, promoting their dispersion and preventing agglomeration.
Compatibilizers
Maleic Anhydride Grafted Polymers
Maleic anhydride grafted polymers can improve compatibility between dissimilar polymers or between polymers and additives. They have reactive functional groups that can bond to polymer chains or surfaces, enhancing adhesion and compatibility.
Functionalized Polyolefins
Polyolefins modified with functional groups such as maleic anhydride or epoxy can act as compatibilizers in polymer blends or filled systems. They improve adhesion between phases and promote dispersion of fillers or additives.
Processing Aids
Slip Agents
Slip agents reduce friction between polymer chains during processing, improving flow properties and reducing melt viscosity. This can prevent sticking to processing equipment and improve surface appearance of the final product.
Antioxidants and Stabilizers
Antioxidants and stabilizers protect the polymer from degradation during processing and storage, preserving its properties and performance. They can improve the stability of the masterbatch and prevent colour or property changes over time.
Other Additives
Flow Enhancers
Flow enhancers improve the flow properties of the polymer melt during processing, reducing shear stress and improving mold filling. This can lead to faster cycle times and better surface finish in molded parts.