A tutorial review of linear rheology for polymer chemists: basics and best practices for covalent adaptable networks

Abstract

This tutorial review of linear viscoelasticity is targeted at polymer chemists working with covalent adaptable networks. It provides an overview of concepts, analysis, misconceptions, and best practices for rheological experiments.

Thermoswitchable catalysis to inhibit and promote plastic flow in vitrimers

“…Given what is known about the molecular basis of vitrimer rheology, 15,19,36,69 we propose that the observed peculiar dynamic behaviour can be explained by a change in the availability of protonated ammonium species [RNH 3 + ]. More particularly, it can be rationalised for stronger (sulfonic) acids that the amount of available acidic protons remains the same at each investigated temperature and that the acid-base equilibrium is shifted to the catalytic active protonated side and subsequently leads to an Arrhenian behaviour.…”

Photocurable acylhydrazone covalent adaptable networks with fast dynamic exchange and tunable viscoelastic properties

“…The characteristic relaxation time ( τ ) was obtained from the fitting of the double Maxwell function 62 , 63 (eqn (S1)†), and the activation energy ( E a ) was calculated from the slope of the curve of ln ( τ ) vs . 1000/ T (seen in Fig.…”

The multifaceted role of water as an accelerator of the crosslinking reaction of isocyanate-free polyurethane net-works

“…5CC:NH2 = 1:1), without any additives, before introduction in the rheometer (parallel plates, Ø 25 mm) preheated at 40 °C. Their crosslinking reaction was investigated through small amplitude oscillatory shear (SAOS) experiments, 32,33 using Fourier transform mechanical spectroscopy (FTMS) 34 to record the storage (G'(𝜔)) and the loss Scheme 1: Molecular formulae of the reactants used in this study, TMPTC and EDR148, and schematic representation of the solgel transition (G''(𝜔)) moduli at different frequencies, 𝜔, simultaneously (i.e. multiwave mode of the rheometer).…”