Fig. 4: Mechanisms of regenerated membrane formation.
From: Regenerating end-of-life membranes for enhanced sustainability and unexpected performance
The determination of plateau modulus of various casting solutions: (a) Loss modulus as a function of angular velocity. The gray shaded region refers to the maximum of loss modulus (G”max) of membranes. b Plateau modulus. The rheology characterization of casting solutions: (c) Viscosity as a function of shear rate. d K and n values. e Optical image and transmission intensity profiles along the vertical direction of the Ref, EOL-CR, and EOL-R casting solutions. f Reconstructed images of three casting solutions from Turbiscan Tower. The Left vessel in each reconstructed diagram shows the initial existing status of the casting solution sample and the height-time plot shows the changes of existing status throughout the measurement period. Density functional theory calculations: (g) Illustration of diffusion of NMP molecules near low and high entanglement of PVDF chains in initial state (IS), transition state (TS) and final state (FS). h Migration energy barrier of NMP. i A schematic phase diagram of the PVDF/NMP/water ternary system for regenerated and reference systems. The two cloud point curves were determined through titration experiments. Source data are provided as a Source Data file.
