Assessment of Blend PVDF Membranes, and the Effect of Polymer Concentration and Blend Composition

Abstract

In this work, PVDF homopolymer was blended with PVDF-co-HFP copolymer and studied in terms of morphology, porosity, pore size, hydrophobicity, permeability, and mechanical properties. Different solvents, namely N-Methyl-2 pyrrolidone (NMP), Tetrahydrofuran (THF), and Dimethylformamide (DMF) solvents, were used to fabricate blended PVDF flat sheet membranes without the introduction of any pore forming agent, through a non-solvent induced phase separation (NIPS) technique. Furthermore, the performance of the fabricated membranes was investigated for pressure and thermal driven applications. The porosity of the membranes was slightly increased with the increase in the overall content of PVDF and by the inclusion of PVDF copolymer. Total PVDF content, copolymer content, and mixed-solvent have a positive effect on mechanical properties. The addition of copolymer increased the hydrophobicity when the total PVDF content was 20%. At 25% and with the inclusion of mixed-solvent, the hydrophobicity was adversely affected. The permeability of the membranes increased with the increase in the overall content of PVDF. Mixed-solvents significantly improved permeability.

Polysulfone‐based amphiphilic copolymers: Effect of hydrophilic content on morphology and performance of ultrafiltration membranes

“…Effect of kinetic hindrance (increasing viscosity) might be defeated by the enhanced demixing as a result of increased hydrophilicity. Miscibility of P 70 and PSf might be inhibited by the dominant hydrophilic character of the copolymer, which can be resulted in the nonsolvent effect . The size of the macropores increased and skin layer thickness decreased with the dosage of PSf‐ g ‐PEGMA copolymers (P 70 ).…”

Performance Evaluation and Kinetic Analysis of Photocatalytic Membrane Reactor in Wastewater Treatment

“…Although there are four main configurations used for membrane distillation (MD) [ 5 , 6 ], as shown in Figure 1 , the direct contact membrane distillation (DCMD) configuration [ 7 ] is the most widely used due to its simplicity and ease of application. Moreover, the performance of different membrane fabrication materials was investigated, and it was found that polyvinylidene fluoride (PVDF), as a material for membrane fabrication, is a promising one due to its good film-forming ability, thermal stability, high mechanical strength, and excellent chemical and aging resistance [ 8 ]. However, adopting MD for wastewater management was hindered due to some limitations; such as membrane fouling, wetting, high level of feed pretreatment requirements, and inability of some membranes to remove microcontaminants [ 9 ].…”

Preparation of an Ultrafiltration (UF) Membrane with Narrow and Uniform Pore Size Distribution via Etching of SiO2 Nano-Particles in a Membrane Matrix

“…The results of blend methods for PVDF/ PV, PVDF/PS, PVDF/PAN, PVDF/PMMA/CA, and PVDF/SPS systems showed that the blend method is a convenient, widespread and effective method without destroying the structure of the polymer chains [ 22 , 23 , 24 ] in order to prepare a high-quality antifouling PVDF membrane [ 25 , 26 , 27 , 28 , 29 , 30 ]. For example, when high-quality hydrophilicity materials, CA and PMMA, are blended with PVDF, the hydrophilicity and antifouling characteristics of a PVDF membranes can be improved, their lifetime can be prolonged and membrane operating costs can be reduced [ 31 ].…”