Nano Calcium Carbonate Dispersion 50% (Toughening Filler)

Conventional CaCO3 (1–10 μm) acts as an inert extender that can actually reduce toughness and elongation by acting as stress concentrators. Nano CaCO3 (60–100 nm) improves toughness through crack-pinning and crack-deflection mechanisms: the high surface area creates multiple crack-tip energy-absorbing interfaces that arrest crack propagation. In polymer matrices with good nano-particle dispersion, impact strength improvements of 20–50% are achievable at 2–5% nano-CaCO3 loading. Surface treatment (stearic acid) is critical to prevent nanoparticle agglomeration and ensure intimate polymer-particle interface.