Irradiation‐induced grafting of poly(vinylidene fluoride)‐graft‐poly(styrene sulfonic acid) for the preparation of planar and tube‐shaped air‐drying membranes

Abstract

A novel air-drying membrane was developed and investigated as an alternative for planar and tubeshaped drying membranes composed of Nafion V R . The new membrane is based on poly(vinylidene fluoride) (PVDF) polymer types grafted with polystyrene sulfonic acid. Modification of the PVDF membrane by chemical grafting was initiated via c-irradiation of pre-made film and tube-shaped samples. The grafting was conducted while the pre-irradiated PVDF samples were immersed in styrene monomer solution. Three unique characterization methods were introduced to evaluate the ion exchange and barrier functions of the membrane. This investigation focuses on optimizing the degree of grafting yield, and subsequently the control of the membrane's overall functional performances, through (1) monitoring the PVDF's degree of crystallinity and (2) monitoring the styrene monomer solution temperature, respectively. Different levels of crystallinity were achieved by melt blending the PVDF-copolymer with PVDFhomopolymer, in various mixing ratios. Another variable examined in this investigation was the introduction of an ionic complex on the sulfonic acid end groups, and its effect on the membrane functional performance was studied.

Effect of electron irradiation on electroactive phase and dielectric properties of PVDF films

“…[10][11][12][13] The effect of irradiation on the gel of PVDF was studied, and the results showed that the gel increased quickly at the initial stage at doses below 10 13 cm À2 , which is ascribed to the crosslinking reaction during irradiation greatly affecting the crystal structure of the sample. 14,15 Due to nonlinear effects in the proton irradiation, the number of radicals produced is lower than that of electron irradiation. Dimensional adjustments of adaptive polymer lms depend on charge deposition and require the detailed understanding responses of piezoelectric material which are expected to deteriorate owing to strong vacuum UV, energetic particles and atomic oxygen exposure in space.…”