Acrylic acid (AAc) and 2-acrylamide-2-methylpropanesulfonic acid (AMPS) were successfully grafted on polyterafluoroethylene (PTFE) powder by the fact that γ-ray radiation induced graft coploymerization for preparation of high hydrophilic PTFE powder.The chemical structure and hydrophilicity of the grafted PTFE powder were characterized by Fourier transform infrared spectrometer (FTIR)

X-ray photoelectron spectroscopy (XPS) and contact angle (CA)test.The surface morphology of the grafted PTFE powder was observed through scanning electron microscope (SEM).The electric potential of the grafted PTFE powder dispersion was determined by zeta potential test.The thermal stability of the grafted PTFE powder was analyzed by thermogravimetric analysis (TGA).It was found that the hydrophilicity and dispersion stability of modified PTFE powder was significantly improved with increasing grafting yield of AAc and AMPS.The PTFE powder with a grafting yield of 26.6% can be stably dispersed in water for a long period

which was prepared in the solution with the monomer concerntration of 20% and the AAc/AMPS ratio of 2 at 70℃.Water contact angle of the PTFE powder decreased from 148.8° before grafting to 30.2° after grafting.Simultaneously

the corresponding zeta potential of PTFE dispersion decreased from-4.3 mV to-83.4 mV.