Organic acid-based filler surface treatment systems are essential additives for the production of filled polymers. Demand for fatty acids is expected to increase, as the requirement for highly filled flame-retardant compounds filled with metal hydroxides increases. The production of organo-clays for nanocomposites is another growth area, where the intercalants used are derived from fats. While silane-based systems continue to dominate in reactive interphase modifier systems, reactive acid derivative systems may also have a future.
Organic acids, particularly fatty acids, are extensively used as surface treatment systems for particulate mineral fillers. Filler surfaces are modified for a number of reasons. Firstly, their use aids filler production, particularly for precipitated calcium carbonates. Without the treatment, the filter cakes would shrink excessively, forming strongly bound agglomerates that are difficult to disperse in the matrix. Filler stability is another factor. Fatty acid modification causes the filler surface to become hydrophobic and moisture adsorption during storage is significantly reduced.