Aerosol filtration properties of nucleating agent containing electret filters

Abstract

This study reports on the effects of nucleating agents on morphology, charging, and electrostatic filtration performance of polypropylene meltblown webs. Two commercial nucleating agents, DMDBS (3:2, 4‐bis(3,4‐dimethyldibenzylidene) sorbitol) and NA11 (sodium 2,2′‐methylene‐bis(4,6‐di‐tertbutylphenyl)‐phosphate) were compared. It is hypothesized that faster solidification brought about by the addition of the nucleating agents may be responsible for the slight increase in fiber diameter and concomitant reduction in web solidity. Samples were charged at room temperature as well as at elevated temperatures. Upon thermal charging, significant enhancement in the electrostatic potential and filtration performance of the webs was observed. Particularly, the stability of electrostatic filtration performance was found to be promising with the addition of these polarizable additives. Dielectric spectroscopy tests confirmed an increase in capacitance for samples containing nucleating agents. POLYM. ENG. SCI., 54:1533–1539, 2014. © 2013 Society of Plastics Engineers

Fabrication, Polarization of Electrospun Polyvinylidene Fluoride Electret Fibers and Effect on Capturing Nanoscale Solid Aerosols

“…Filter media with charged fibers are termed “electrets” [27,28]. In general, an electret is defined as a permanently polarized and electrically insulating material with long-lived internal and/or external quasi-permanent surface charge [29].…”

Electrostatic Capture Efficiency Enhancement of Polypropylene Electret Filters with Barium Titanate

“…After that, absolute difference between front and back values were calculated as the electric field over particles will be close to that value. Detailed explanation of the procedure can be found in our previous work (Kilic et al 2014). …”

Filtration Efficiency of Electret Air Filters Reinforced by Titanium Dioxide

“…At the same time, it also serves as an initial point for heterogeneous nucleation, which facilitates the crystallinity of polymer and effectively enlarges the contact area between crystalline and amorphous regions, which is a trap for charge storage. Hence, the surface potential can be significantly improved [14,15,17]. and 4 wt% of TiO2 exhibit comparable surface voltages in terms of the trend and the value.…”

“…The other approach is to add a nucleating agent that increases the crystallinity of polymers and to obtain greater crystalline and amorphous regions to house more space charges. The nucleating agents are magnesium stearate [13], stearate [14], modified rosin [14], polycarbonate [15], tourmaline [16], DMDBS (3:2, 4-bis(3,4-dimethyldibenzylidene) sorbitol) sorbitol) [17], and NA11 (sodium 2,2 -methylene-bis(4,6-di-tertbutylphenyl)-phosphate) [17].…”