论文部分内容阅读
In order to control the surface pore sizes of polyvinylidene fluoride membranes andtheir distribution,low temperature plasma-induced grafting modifications of PVDF were studiedto prepare hydrophobe membranes.By argon(Ar)treating and subsequent grafting reaction,ahydrophobe monomer,styrene,was introduced into the PVDF membrane.Fourier transform in-frared attenuated total reflection(FTIR-ATR)was utilized to characterize the chemical and physi-cal changes in the Ar plasma modified membrane.The surface modifications of PVDF membraneswere investigated by using scanning electron microscopy(SEM),atomic force microscopy(AFM)and differential scanning calorimeter(DSC).The water permeability and the solute rejection weremeasured by PVDF membrane modified in different graft conditions.Results demonstrated thatthe pores in the modified membranes get smaller and the distribution of pores gets narrowedwith the increase in grafting reaction duration.Longer graft time caused the water flux of PVDFmembrane to decrease from 578 kg/(m~2·h)to 23 kg/(m~2·h)and the solute rejection to increasefrom 73% to 92%.
In order to control the surface pore sizes of polyvinylidene fluoride membranes and the distribution of low temperature plasma-induced grafting modifications of PVDF were studied to prepare hydrophobe membranes. By argon (Ar) treating and subsequent grafting reaction, ahydrophobe monomer, styrene, was introduced into the PVDF membrane. Fourier transform in-frared attenuated total reflection (FTIR-ATR) was utilized to characterize the chemical and physi-cal changes in the Ar plasma modified membrane. The surface modifications of PVDF membranes were investigated by using scanning electron microscopy (SEM), . The water permeability and the solute rejection were measurable by PVDF membrane modified in different graft conditions. Results that the pores in the modified membranes get smaller and the distribution of pores gets narrowed with the increase in grafting reaction duration. Longer graft time caused the water flux of PVDF megabytes ane to decrease from 578 kg / (m ~ 2 · h) to 23 kg / (m ~ 2 · h) and the solute rejection to increase from 73% to 92%.