Study on the preparation of porous polyethylene glycol terephthalate film and the influencing factors of etching rate

Porous polyethylene glycol terephthalate (PET) film is a kind of mesopore structure template with pore size ranging from nanometer to micrometer by chemical etching after irradiation of heavy ions. The etching rate is an important factor affecting the pore morphology and quality of the membrane. In this paper, four stacked PET film were irradiated with 140 MeV 32S ions at room temperature and vacuum. During chemical etching of irradiated samples, the path etching rate Vt was determined by conduction method, and the bulk etching rate Vb was determined by weighing method. The relationship between etching temperature, concentration, sensitization time, and etching rate was studied. The results show that the etching rate is exponentially correlated with the etching temperature, and increases linearly with the increase of the etching solution concentration. When the concentration of NaOH is 3 mol center dot L-1 and the etching temperature is 75 degrees C, the formation of cylindrical micropores is the most favorable. The pore size of porous PET film can be adjusted, and the relationship between pore size and etching time is dnm=15nm+0.24t$$ d\left(\mathrm{nm}\right)=15\mathrm{nm}+0.24t $$. This is of great significance for the preparation of nanowires with uniform size and stable properties.Highlights We have obtained the optimal conditions for obtaining cylindrical holes. The relationship between the diameter of holes and etching time were determined. The optimal etching conditions and the etching rate for preparing cylindrical pores on PET films. image