The Development of PVDF/Pei Blended Membrane: Effect of Stirring Time on Membrane Characteristics and Performance

Abstract

The increased characteristics and performance of polyvinylidene fluoride (PVDF) membrane were investigated using polyetherimide (PEI) as a high-performance co-polymer for increased porosity, mechanical strength, PWF and thermal also chemical stability. The blend solution was prepared using a composition 2%PVDF/12%PEI/84%NMP/2%PEG-6000 (wt.%) with varying stirring time (7h, 12h, 16h, and 20h). The formation of a solid PVDF/PEI membrane was obtained using a non-solvent induced phase inversion (NIPS) method. Analysis of physical (surface and cross-section morphology, porosity, pore size) and mechanical (Young's modulus) characteristics, performance (PWF), thermal and chemical stability of the blended membranes were performed to evaluate the significance of stirring time effect. The resulting infrared spectra have confirmed the formation of PVDF/PEI blended membrane. All PVDF/PEI blended membranes were found to have symmetric structures with porosity 6.17% -30.64% and pore size 0.204 nm -0.366 nm. The increase in mechanical strength can be seen from changes in Young's modulus values as the stirring time increases up to 12 hours. However, the stirring time for 16 and 20 hours resulted in a cast solution with too high viscosity resulting in a defect in the casting film using the automatic-casting knife. Increasing the homogeneity of PVDF/PEI cast solution as increasing stirring time has led to PEI characteristic properties that are capable of producing high PWF. This PVDF/PEI mixing method is a potential solution to obtain higher PVDF thermal stability and PEI chemical resistance.

Development of a New Polymer Membrane: Polyvinylidene fluoride/Polyetherimide Blend Membrane

“…The narrower pore size distribution on pure PVDF membranes is predicted to be the determinant of this characteristic. This finding is slightly different from previous studies which produced asymmetric PEI membranes with lower pore sizes [35]. This condition is thought to occur due to differences in pyrogen additives.…”

“…3(e3)). Furthermore, detection of fluorine (F) atoms contamination on the M8 membrane also influences membrane formation with characteristics slightly different from previous studies [35]. However, it is important to further analyses the pore size distribution on the membranes of M1, M2, M5, M7 and M8 to strengthen the assumption.…”

Flexible PEI/PVDF Blend Films with an Enhanced Curie Temperature for Piezoelectric Energy Harvesting

“…The reduction in free volume also limits the mobility of molecular chains, resulting in a compact structure. The interchain movement of polymers must therefore be activated by greater heat, which raises the T m in the blend film …”

“…The interchain movement of polymers must therefore be activated by greater heat, which raises the T m in the blend film. 24 Surface Morphology. The surface morphology of the pristine PVDF film and the blend film is shown in Figure 7.…”

Micromechanism Study of Molecular Compatibility of PVDF/PEI Blend Membrane

“…From the surface morphology, it can be seen that all membranes present a symmetric structure, and the addition of PEI does not change the overall structure of the membrane. With the increase in PEI content, the membrane began to appear in a honeycomb structure, this is because PEI is a hydrophilic substance, the hydrophilic influence of amide groups on the surface indicates that PVDF and PEI have a good compatibility [22]. With the increase in PEI content, crude fiber exists at 20%, which may be because the electrostatic force between PEI and PVDF is weakened due to the increase in PEI content, which reduces the diffusion rate between the solvent and the non-solvent.…”