Preparation of Lateral Flow PVDF Membrane via Combined Vapor- and Non-Solvent-Induced Phase Separation (V-NIPS)

Abstract

A large pore size Poly(vinylidene fluoride) (PVDF) membrane was prepared by the V-NIPS method using PVDF/N, N-dimethylacetamide (DMAc)/Polyvinyl pyrrolidone (PVP)/Polyethylene glycol (PEG) system. Firstly, the effect of different additive ratios on the membrane morphology and pore size was studied, and it was found that when the PVP:PEG ratio was 8:2, PVDF membranes with a relatively large pore size tend to be formed; the pore size is about 7.5 µm. Then, the effects of different exposure time on the membrane morphology and pore size were investigated, and it was found that as the vapor temperature increased, the pores on the surface of the membrane first became slightly smaller and then increased. Finally, the effects of different vapor temperatures on the membrane properties were discussed. The results showed that the as-prepared membrane exhibited suitable capillary flow rate and similar performance compared with a commercially available membrane in colloidal gold tests. The likely cause is that the amount of negative charge is less and the capillary migration rate is too fast. This paper provides a reference for the preparation of PVDF colloidal gold detection membrane.

Effect of Zn–Fe2O3 nanomaterials on the phase separated morphologies of polyvinylidene fluoride piezoelectric nanogenerators

“…Phase separation is an emerging structural modication method for enriching the electroactive phases in PVDF-based polymers, making dipole alignment feasible for piezoelectricity. Quick and low-cost phase separation processes involving liquid or vapour solventnon-solvent molecule interactions 16 on the polymer chains report outstanding crystallinity enhancement and piezoelectric sensitivity. 17 Iron(III) oxide (Fe 2 O 3 ) is a well-known semiconductor material with interesting properties.…”