Some observations on the flow behavior of polyvinyl chloride melts

Melt studies on PVC systems at elevated temperature or long times are difficult. One consequence is that measurements may be possible only in the non‐Newtonian region. The results indicate that even in this case the melt viscosity can be related exponentially with the weight average molecular weight by the 3.4 power. Since literature data are scarce, attempts were made to extend the range by mixing polymers. This led to the complication of dispersity both on a molecular scale and on a macroscopic level. The latter point is particularly important for PVC studies since the polymers are frequently blended with materials having different viscosities.