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The choice of plasticizer for extrusion of flexible vinyl profiles is usually made for product performance properties. This paper deals with plasticizer influence on the entire extrusion process from dry‐blend preparation to final extruded profile. Undestanding the effect of plasticizer throughout the extrusion line helps the compounder optimize for higher production rates, lower energy input, improved profile quality and better final physical properties. This study focused on the effect of low molecular weight, fast fusing plasticizers in the extrusion processing of general purpose formulations. Butyl benzyl phthalate was used as partial replacement for dialkyl phthalates. A positive influence of this replacement was observed in dry‐blend preparation, in the compound extrusion step, in the finished extrusion step and in final product quality.

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Investigations of chemically‐blown vinyl foam systems, based on electrical grade plasticizers, have shown that the inclusion of 2,2′‐bis (4‐hydroxyphenyl) propane (BPA) as an antioxidant results in color formation in the finished foam. Color formation appears to be due to interactions between BPA and the azodicarbonamide blowing agent. Metal ion(s) present in vinyl stabilizer/kickers are also shown to have an effect on color hue though not on color development per se. Mechanisms for the development of quinoidal and diazo color bodies, based on the reaction of BPA and azodicarbonamide are postulated. Based on these reaction mechanisms, it is shown that it is possible to choose an antioxidant that will not interact with azodicarbonamide. A rudimentary screening procedure is described for evaluating these systems.