Inorganic fillers often carry surface hydroxyls and metal ions that adsorb polar components. Pre-mixing the phosphate into the resin phase can reduce direct consumption by filler surfaces; strongly alkaline fillers may neutralise phosphate groups and cause thickening or gelling.
In highly filled systems, the monomer's contribution to viscosity and dispersion must be evaluated separately from the dispersant. Compare a blank, dispersant-only and dispersant-plus-monomer set, recording grind fineness, viscosity, thixotropy and storage change.
KM2130 and KM2140 offer flexibility and compatibility for selected filler interfaces. KM2110 provides stronger anchoring but its high acid value also raises compatibility risk.