1. Introduction
Poly(vinylidene fluoride) (PVDF), owning good heat, corrosion and solvent resistance[l], be
prepared into flat sheet membranes and hollow fiber membranes [2], which are widely applied to
various fields such as water purification, organic solvent refining and membrane distillation. So
PVDF membranes, as a kind of functional material, their preferential separation process is of high
efficiency, low energy consumption, easy manipulation and no secondary pollution. However, PVDF
is a hydrophobic polymer [3], so PVDF membranes are vulnerable to the pollution of some
hydrophobic substance especially organics, which brings about decreasing their permeability,
separation performance and service life.
