The work shows that the compounder should know resin properties in order to benefit from processing equipment developments.

Journal of Vinyl & Additive Technology

The increased use of multi-screw (twin) extruders by pipe producers brought on this study of available PVC homopolymer “pipe grade” resins. Basic tests on resin were examined via a “Correlation Matrix” computer program. Highly significant test data were determined to be internal pore volume and centrifuge plasticizer adsorption. Additional compound evaluation proceeded via torque rheometer followed by twin-screw extrusion. Significant resin test values affecting extrusion properties are inherent viscosity, apparent bulk density, porosity uniformity and melt viscosity. The work shows that the compounder should know resin properties in order to benefit from processing equipment developments.

The work shows that the compounder should know resin properties in order to benefit from processing equipment developments.

Effect of PVC resins on multi‐screw pipe extrusion