Mechanical and electret properties of polypropylene unwoven fabrics reinforced with POSS for electret filter materials

A novel polypropylene/Polyhedral oligomeric silsesquioxanes (PP/POSS) composite unwoven fabric with permanent electret was prepared through melt-blown process with corona charging. Field-emission scanning electron microscope (FESEM) and wide-angle X-ray diffraction (WAXRD) were employed to investigate the morphology of the composite fibers and the distribution of POSS nanoparticles on the surface of the fibers, respectively. POSS acted as nucleating agent and accelerated the crystallization process during nonisothermal cooling. The utmost stable charge density of PP/POSS melt-blown unwoven fabric was improved by 78.4% compared with the neat PP unwoven fabric. The maximum value of collection efficiency measured by monodisperse polystyrene aerosol (PSL) (particle size: 0.3 mu m) collection could reach 97.36% for PP/POSS composite melt-blown unwoven fabric, which improved by 9% compared with neat PP melt-blown unwoven fabric. Moreover, both stress and elongation at break of the PP/POSS melt-blown unwoven fabrics were improved compared with PP unwoven fabric.