关键词: 膜蒸馏, 中空纤维膜, 耐辐照性能, 聚丙烯, 聚四氟乙烯, 聚偏氟乙烯

Abstract: Theeffect of γ ray on the properties of polypropylene (PP), polytetrafluoroethylene (PTFE) and polyvinylidene difluoride (PVDF) hollow fiber membrane materials was studied. The dose rate of 5.1 kGy/h and the doses of 0.5, 1, 5, 10, 30, 50, and 60 kGy were used to irradiate three kinds of membrane materials respectively. The relevant performance characterization parameters of the samples before and after irradiation were tested and compared. The results showed that after irradiation treatment, the thickness, maximum pore size, water permeability pressure and gas flux of the three membrane materials basically have not been changed, while the mechanical properties and hydrophobicity have been changed significantly. With the increase of irradiation dose, the fracture strength, elongation and fracture pressure of PP and PTFE membranes showed a downward trend, while the fracture strength, elongation and fracture pressure of PVDF showed an increasing trend first and then decreasing; When the irradiation dose of the three kinds of membrane materials is 50 and 60 kGy, the water contact angle of some membrane wires will drop significantly, and even hydrophilicity will occur. This shows that 0-60 kGy γ irradiation dose was not enough to change the pore structure of the membrane, but could destroy the surface properties of the membrane and form hydrophilic groups and unsaturated bonds. Through comparison, it is determined that the most suitable material for membrane distillation before irradiation is polyvinylidene fluoride; At the same time, among the three materials, the most radiation resistant material is polyvinylidene fluoride, followed by polypropylene, the most sensitive to radiation is polytetrafluoroethylene.

Key words: membrane distillation, hollow fiber membrane, irradiation resistance, polypropylene, polytetrafluoroethylene, polyvinylidene difluoride