Herein, the numerical simulation of polymeric membrane formation is investigated when a coupling between phase separation and solvent evaporation occurs. A binary polymer/solvent system considered simulations were performed in 2D geometries, first horizontal plan, then vertical cross-section plan. The was simulated using Cahn-Hilliard equations Flory-Huggins theory used to describe thermodynami...

This paper is devoted to the global well-posedness of two Diffuse Interface systems modeling motion an incompressible two-phase fluid mixture in presence capillarity effects a bounded smooth domain $\Omega\subset \mathbb{R}^d$, $d=2,3$. We focus on dissipative mixing originating from mass-conserving Allen-Cahn dynamics with physically relevant Flory-Huggins potential. More precisely, we study N...

This work uses a method based on indentation to characterize a polydimethylsiloxane (PDMS) elastomer submerged in an organic solvent (decane, heptane, pentane, or cyclohexane). An indenter is pressed into a disk of a swollen elastomer to a fixed depth, and the force on the indenter is recorded as a function of time. By examining how the relaxation time scales with the radius of contact, one can...

New experimental data have been collected on thermodynamic properties of solutions of poly(2,6dimethyl-1,4-phenylene oxide) (PPO) in toluene. The Flory-Huggins interaction parameters g have been determined from light scattering measurements. These values are in agreement with values obtained by osmotic measurements a t low concentrations and they allow the calculation of a melting point curve w...

Dissipative particle dynamics (DPD), a mesoscopic simulation approach, is used to investigate the effect of volume fraction of polyethylene (PE) and poly(l-lactide) (PLLA) on the structural property of the immiscible PE/PLLA/carbon nanotube in a system. In this work, the interaction parameter in DPD simulation, related to the Flory-Huggins interaction parameter χ, is estimated by the calculatio...

Macromol. Biosci. 2002, 2, 207 –213 Full Paper: Calcium ions are introduced to sodium polyacrylate gels swollen in sodium chloride solutions and the volume transition is measured by osmotic and small-angle neutron-scattering. The osmotic pressure is found to depend on the sodium chloride con­ centration, indicating that calcium preferen­ tially replaces condensed sodium ions, a result supported...

The phase behavior of a melt of monodisperse rod-coil diblocks is studied. We derive a Landau free energy functional for both a compositional and a nematic order parameter. The excluded volume interaction between the rod blocks is modeled by an attractive Maier-Saupe interaction. The incompatibility between rodand coil blocks is modeled by the usual Flory-Huggins interaction. For a large volume...

In general liquid–liquid demixing processes are responsible for the porous morphology of membranes obtained by immersion precipitation. For rapidly crystallizing polymers, solid–liquid demixing processes also generate porous morphologies. In this study, the interference of both phase transitions has been analyzed theoretically using the Flory–Huggins theory for ternary polymer solutions. It is ...

The aim of this study was to determine and compare the melting (Tm), glass transition (Tg) and mechanical relaxation (Tα) temperatures of a new waxy cassava starch. Thermal transitions measurements were obtained by Differential Scanning Calorimetry (DSC) and Dynamical Mechanical Thermal Analysis (DMTA). The experimental data showed a high correlation between water volume fraction and melting te...

Isothermal phase diagrams for the semicrystalline poly-L-lactide (PLLA) and the amorphous poly-DL-lactide (PDLLA) in combination with several solvent-nonsolvent combinations (dioxane/water, dioxane/methanol, chloroform/methanol, and NMP/water) have been determined. The locations of the liquid-liquid miscibility gap, the solid-liquid miscibility gap and the vitrification boundary in the isotherm...