High-performance electret and antibacterial meltblown nonwovens doped
with nanoparticles of boehmite and ZnO for air filtration
Abstract
The current pandemic caused by Covid-19 triggered intensively the
development of high-performance air filters. Polypropylene (PP) is
widely used as the raw material of meltblown nonwovens that is the core
layer in air filters, such as, masks. In this study, an electret PP
meltblown nonwoven with antibacterial activity was developed, and nano
boehmite (AlOOH) and nano-ZnO employed as electret and antibacterial
agent, respectively. 0.5-2.0 wt% of AlOOH and 1.0 wt% of ZnO were
doped into PP matrix using a twin-screw extruder and the resulting
masterbatches applied as raw materials to afford nonwovens via a
meltblown process. The as-prepared nonwovens were characterized by means
of SEM, IR and DSC/TG, and after corona charging, the filtration
efficiency, charge decay and antibacterial properties were evaluated.
More than 1.0 wt% dosage of AlOOH endowed the nonwoven with high
filtration efficiency and 1.0 wt% of ZnO brought about antibacterial
activity. Corona charging was an effective means to make the nonwovens
electret charged and the charges were quicker to decay in air than in a
sealed bag. The as-prepared meltblown nonwoven would be a remarkably
promising filter in air filtration.