Article

Effect of processing parameters on fusion and mechanical properties of a twin‐screw extruded rigid PVC pipe

Journal of Vinyl and Additive Technology (Impact Factor: 1.11). 04/2004; 9(2):81 - 89. DOI: 10.1002/vnl.10067

ABSTRACT The effect of varying mass temperature and screw speed on the fusion level and mechanical properties of a rigid PVC pipe produced by a twin-screw extruder has been investigated. Differential Scanning Calorimetry (DSC) and capillary rheometry have been used to determine pipe fusion levels. While yield stress was shown to be completely insensitive to fusion level, a very distinct maximum of falling weight and notched Charpy impact strengths and elongation at break was observed at moderate fusion level. Short-term burst strength values increased with degree of fusion while hydrostatic internal pressure tests revealed optimum resistance for pipes of varying fusion level. The effect of processing temperature on fusion in the Brabender Plasticorder was also examined.

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