The Cole–Cole plot for cure: The cure and reversion of natural rubber

Abstract

Cure rheometry is routinely used in the rubber industry for processability assessment and cure-time determination. This article examines these rheological outputs in Cole-Cole format to explore what new insights can be gained from this alternative data plot. It differs from the conventional Cole-Cole treatment in its application to a reacting system. The plots described here are therefore of G 00 (t) vs. G 0 (t). Initially some attention is directed to the basics of the Cole-Cole treatment and the likely features to be expected when applied to systems undergoing both cure and reversion. This article goes on to consider examples of both by studying a natural rubber vulcanization at temperatures of 160 8C and above. Through the Cole-Cole approach, it is thought possible to identify the competition between intermolecular and intramolecular sulfurization, and between crosslink and main-chain scission. The approach offers considerable potential to expand the capabilities of cure rheometry.

Effect of nitrocellulose (NC) on morphology, rheological and mechanical properties of glycidyl azide polymer based energetic thermoplastic elastomer/NC blends

“…A Cole − Cole plot describes the two‐phase microstructures of polymer blends; it shows a plot of the imaginary viscosity ( η ′′) versus the real viscosity ( η ′), where η ′′ = G ′/ ω and η ′ = G ′′/ ω . A smooth, semicircular shape of the graph suggests miscible blends with a homogeneous phase.…”