Preparation And Characterization Of Silica Reinforced Micro-porous PVDF Films

Micro-porous films of PVDF/SiO₂ were prepared through solution blending using silica nanoparticles and polyvinylidene fluoride(PVDF)as raw materials and dibutyl phthalate(DBP)as the micro-pore makers.The influence of type and proportion of solvents(Acetone and N,N-Dimethyllformamide)and the surface properties of silica nanoparticles on the films was investigated.The mechanical properties and porous ratio of the prepared films under different preparation conditions were measured,and the appearance of the films were characterized by the scanning electron microscope(SEM). The effect of SiO₂ content on the micro-structure of the film was also investigated.The results showed that the mass proportion of the solvent had a significant influence on the mechanical properties of the obtained films.As the mass proportion of acetone with N,N-Dimethylformamide was 19:1,the obtained PVDF films demonstrated the best mechanical properties.As the content of silica nanoparticles increased,the mechanical property of the film was strengthened first,and then was reduced.The mechanical strength of silica reinforced PVDF films had the maximum value as the silica content achieving 20 wt%,and the tensile strength was 6.36 MPa.Moreover,as the surface property of silica nanoparticles turned to hydrophobic from hydrophilic,the PVDF films were strengthened obviously.The porous ratio of the film increased as the silica content increasing.