Effect of Triton-X on the preparation of Nafion/PTFE composite membranes

The composite membranes were prepared by impregnation of porous poly(tetrafluoroethylene) (PTFE) membranes with Nafion solutions containing various contents of surfactant Triton® X-100 (polyethylene glycol tert-octylphenyl ether). Dynamic light scattering (DLS) was used to investigate the polymer aggregations sizes distributions of Nafion solutions. The scanning electron microscope (SEM) and energy dispersion X-ray (EDX) analyzer were used to study the morphology of the surface of composite membranes. The experimental results revealed that mixing 1–3 wt.% of Triton® X-100 into the Nafion solutions causes the dissociation of Nafion aggregations in the solutions. Thus, the Nafion molecules are easy to penetrate into the pores of PTFE membranes, leading to a better ionic conductivity and lower gas permeability of composite membranes.