Coated precipitated calcium carbonate (CPCC) provides an unique combination of beneficial processing properties to the manufacture of rigid cellular PVC.

In order to obtain an optimum level of density reduction, formulations need to feature a compromising set of melt properties. The melt strength and elasticity have to be high but the melt viscosity low. Without these rheological characteristics the generated gas cannot be retained and cell structure will collapse forming voids and even surface bubbles.

CPCC has the effect of providing melt reinforcement which manifests itself as improved melt elongation and elasticity. Some benefits in rapid set up after the die together with possible nucleation effects have also been observed.

Benefits of CPCC in rigid foam: