Polymer molecular‐weight distribution from dynamic melt viscoelasticity

A method is developed by which polymer molecular weight and its distribution can be accurately determined by deconvolution of dynamic melt viscoelastic properties in the terminal and plateau zones. The method is illustrated with a series of monodisperse (narrow-distribution) and polydisperse (broaddistribution) polystyrenes. The Mn, Mw, and Mn/Mw values obtained are in excellent agreement with those determined by light scattering, osmometry and gel permeation chromatography with less than 5 to 10 percent error. The differential molecular-weight distribution curves obtained coincide wall with those obtained by gel permeation chromatography. The method is applicable to insoluble as well as soluble polymers.

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