AbstractA study was conducted to evaluate mica‐poly(vinyl chloride) (PVC) composites. A highly filled PVC pipe formulation was selected as reference and a gradual replacement by mica of the calcium carbonate was conducted. The mica improved the fluxing time of the formulation by a factor of three without markedly affecting the equilibrium or maximum, torque. The results are optimized when there is a partial replacement of the calcium carbonate by mica, Orientation of the mica flakes enhances the young's modulus as well as the yield stress. A theoretical analysis shows a discrepancy from experimental results for high levels of mica. The rheological properties were studied with a Brabender plastograph and mechanical properties with a model TM‐SM Inst