Shear Rheology and ~1H TD-NMR Combined to Low-Field RheoNMR: Set-Up and Application to Quiescent and Flow-Induced Crystallization of Polymers

摘要

Rheology provides access to the flow properties of soft matter, while ~1H TD-NMR is a useful technique for the characterization of molecular dynamics. To achieve greater insight into the interplay of these domains, especially under flow, it is desirable to combine these two methods in one set-up. We present a low-field RheoNMR set-up based on a portable 30 MHz ~1H NMR unit that was integrated into a commercial strain-controlled shear rheometer. This unique combination can simultaneously conduct a full rheological characterization (G', G", |n*|, FT-Rheology: I_(3/1), Q_0) while monitoring molecular dynamics in-situ via ~1H TD-NMR for temperatures from -15 to +210 °C. Possible applications include the quantitative measurement of the composition in multiphase systems (fats, polymers, etc.) and soft matter during the application of flow, e.g. measurements on the flow-induced crystallization of polymers.