Brief Introduction to ABS Filler Masterbatch Formulation

The main component of ABS filler masterbatch is generally filler, along with small amounts of carrier resin, coupling agents, and dispersants. For flame-retardant ABS, antimony bromide flame-retardant masterbatch can be considered, with the addition of a small amount of aluminum hypophosphite flame retardant for synergistic effect. Common plastic fillers include talc, wollastonite, kaolin, and mica. Calcium carbonate is a widely used inorganic filler in plastic processing due to its wide availability and low price. Calcium carbonate filler has numerous micropores on its surface, resulting in a large specific surface area and strong adsorption capacity. Using it as a plastic filler can not only reduce product costs and improve creep resistance but also increase the heat distortion temperature and dimensional stability of the product. When adding calcium carbonate to ABS, a whiteness greater than 80% and a particle size less than 19.7 μm are generally required, and the particle surface must be treated.

Common carrier resins in ABS filler masterbatch include CPE, HIPS, SBS, and EPDM-g-MHA. Carrier resins enable fillers to be uniformly dispersed in the matrix resin while maintaining their original mechanical properties. They also provide sufficient coating, wetting, and bonding to the fillers, and offer some toughening and modification benefits. When selecting a carrier resin, it should have good compatibility with the matrix resin, good processing fluidity, and its melt flow rate should generally be higher than that of ABS resin. Common coupling agents include titanates, aluminates, and silanes. These coupling agents typically increase the interfacial bonding force between the filler and ABS, allowing the filler to organically combine with the carrier resin, thereby reducing the negative impact of the filler on the product, improving processing performance, and enhancing product quality.

Dispersants prevent filler re-agglomeration during plasticizing and promote uniform dispersion of the filler in ABS. They improve the processing fluidity of the material and increase the gloss of the product. It is important to note that stearic acid should not be used as a dispersant when selecting coupling agents in the masterbatch, as this will reduce the efficiency of the titanate; however, when using aluminate coupling agents, stearic acid is preferable as a dispersant due to the good synergistic effect between the two.