Electrostatically Active Polymer Hybrid Aerogels for Airborne Nanoparticle Filtration

Abstract

The role of electrostatic force on separation of airborne nanoparticles is evaluated in this work by considering a hybrid monolithic aerogel of syndiotactic polystyrene (sPS) and polyvinylidene fluoride (PVDF). The sPS part accounts for open pore structures in the monolith, while the PVDF chains contribute spontaneous polarity for particle capture by the electrostatic force. The hybrid aerogels are fabricated by thermoreversible gelation of sPS from a solution with PVDF in tetrahydrofuran followed by supercritical drying of the gel. sPS is present as the δ-form clathrate crystalline phase and PVDF as α- and γ-form crystalline phases in the hybrid. The presence of PVDF induces significant static charges on the surfaces of hybrid aerogels. The filtration efficiency is determined by passing airborne NaCl nanoparticles with diameter in the range 25-150 nm through the filter media. The experimental data reveal that air permeability of the hybrid system (∼10 m) is close to that of sPS monoliths. The hybrid materials show filtration efficiency ≥99.999% in comparison to 98.889% observed for a sPS monolith with the same solid content.

Effect of network connectivity on the mechanical and transport properties of block copolymer gels

“…These properties consequently afford gels the capacity to satisfy a number of applications. Such applications include flexible electronics and fuel cells, 1,2 3D printable media, 3 filtration of both liquid 4 and gaseous 5 media, and biomedical applications including soft tissue replacement, 6,7 and drugdelivery vehicles. 8,9 While hydrogels have fulfilled several of these roles, particularly in the realm of drug delivery, lesser-studied organogels are also capable of satisfying many of these applications [10][11][12][13] and have even been proposed recently as transdermal drug delivery devices.…”

Mussel-inspired approach to cross-linked functional 3D nanofibrous aerogels for energy-efficient filtration of ultrafine airborne particles

“…Fe 3+ ions may also offer electrostatic interaction, facilitating the adsorption of negatively charged pollutant particles. 28 Herein we demonstrate that the cross-linked 3D NFAs fabricated using our approach indeed exhibits high porosity and enhanced compression resistance. When such a NFA is combined a commercial high-efficiency particulate arrestance (HEPA) air filter, the hybrid filter exhibits enhanced filtration efficiency for ultrafine particles with only a slight increase in pressure drop.…”

Functionalized Polyvinylidene Fluoride Electrospun Nanofibers and Applications

“…The PVDF materials with modified properties are of significant practical interest. In filtration, for example, an exceptional particle capture efficiency of ≥99.999% was achieved by a hybrid monolithic electret aerogel composed of syndiotactic polystyrene (sPS)/PVDF [54], whereas 98.9% filtration efficiency was recorded with sPS monolithic aerogel comprised of similar solid content. In comparison, performance of cellulose acetate electrospun fibers with diameters in the range from 0.1 to 24 μm challenged with a solid brine aerosol (NaCl) and a liquid aerosol of (diethyl hexyl sebacate) showed a maximum efficiency of 70% and with the most penetrating particle size in the range of 40-270 nm [55].…”