Electroosmotic Water Vapor Transport across Novel, Smart, Functionalized Conducting Polymer Microporous Membranes in Active Mode at Very High Rates, with Concomitant Chemical Warfare (CW) Agent Blocking

Abstract

<span><span style="font-family:Verdana;">Electroosmotic water vapor transport (WVT) across very thin, flexible, functionalized conducting polymer (CP) microporous (μP) membranes at a very high rate is reported. Both </span><i><span style="font-family:Verdana;">passive </span></i><span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">active </span></i><span style="font-family:Verdana;">(6 VDC applied) WVT are reported, the latter</span></span><span> </span><i><span style="font-family:Verdana;">for the first time ever</span></i><span><span style="font-family:Verdana;">. WVT occurs with concomitant, effective blocking of chemical warfare (CW) agents, again demonstrated for the first time ever. Initial </span><i><span style="font-family:Verdana;">active</span></i><span style="font-family:Verdana;"> liquid||membrane||liquid interface studies demonstrated WVT rates of >1.7 × 10^-5g</span>^{<span style="font-family:Verdana;vertical-align:baseline;"> .</span>}<span style="font-family:Verdana;">mm^-2</span><span style="font-family:Verdana;">s^-1</span><span style="font-family:Verdana;">, >3 × the highest prior reported values of 5 × 10^-6g.</span><span style="font-family:Verdana;">mm^-2</span><span style="font-family:Verdana;">s^-1</span><span style="font-family:Verdana;">. Subsequent vapor||membrane||</span></span><span> </span><span><span style="font-family:Verdana;">vapor interface studies using industry-standard methods (including ASTM E96B Upright Cup (“WVT”), ASTM F2298 (“Dynamic Moisture Permeation Cell”) and ASTM F1868 (“Sweating Guard Hotplate”) were done at independent, external labs for independent corroboration. These yielded, e.g., WVT values of2564.4 g.m².</span><span style="font-family:Verdana;">d^-1</span><span style="font-family:Verdana;"> (</span><i><span style="font-family:Verdana;">passive</span></i><span style="font-family:Verdana;">) and3706.7 g.m²</span><span style="font-family:Verdana;">d^-1</span><span style="font-family:Verdana;"> (</span><i><span style="font-family:Verdana;">active</span></i><span style="font-family:Verdana;">), to be compared with the highest (</span><i><span style="font-family:Verdana;">passive</span></i><span style="font-family:Verdana;">) value ever reported previously,984.8 g.m².</span><span style="font-family:Verdana;">d^-1</span><span style="font-family:Verdana;"> for a μP-Nylon membrane. More than 15 different membrane configurations, porosities and types were studied, including membranes with CP + organophosphate hydrolase (OPH), an enzyme reactive to CW agents. Efficient blocking of the actual CW agents GB, HD, VX is also reported, using the TOP-8-2-501standard. Membranes also passed all Industry</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">standard durability tests, e.g. ASTM D2261 (Tearing), ASTM D5034 (Breaking), ASTM D3886 (Abrasion), ASTM F392 (Gelbo Flex). Inco...

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