U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Reactive Materials Research for Self-Detoxifying
CB Protective Clothing
Heidi Schreuder-GibsonU.S. Army Natick Soldier Center
Natick, MA
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Concept
HD Catalyst
Poly(vinyl)amines
O
HO OH
H2COCH2
O
NN
O
O
CH3CH3
Cl
n
CHLORAMINEBactericide, Agent Decon
Place reactive materials in fabrics that detoxifyContaminants on clothing within hours of exposure.
CH2 CH CH
OH NH2m n
CH2
ModifiedCyclodextrins
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
ApproachChloramides & Quats -Shell Fabric
Sporicide and Agent Decon, Water RepellancyPOM Catalysts – Liner Materials
Carbon SurfacesPolymer Film Surfaces
Nanoparticles – Attached to Fabrics, Blended into FibersParticulate Absorbants
Reactive Permselective Membranes - Liners
Bio, HD, VX
HD
HD, VX
G, VX
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
NanoparticleReaction Rate Studies
Depletion of 2-CEES- In Solution- In Vapor
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Comparison of Old and New POMs
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0 5 10 15 20 25 30
Exposure Time (hours)
CEE
S R
emai
ning
(mg)
TiO2New POM
Solution Depletion of 2-CEESNanoparticle TiO2 vs POM Catalyst
Very reactive catalyst
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Equilibrium Vapor Adsorption Measurements
% CEES ADSORBANT Vapor Uptake
Carbon Spheres 56NanoAl2O3 - PLUS 99NanoAl2O3 10NanoTiO2 17
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Thermal Desorption GC/MSSample in Tube
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
NanoA
lumina
PLUS
Shell
Shell+Chlo
ramide
Shell+Nan
o/Chlo
ramide
Diethyl sulfide
Ethyl vinyl SulfideCEES Oxide
Ethylthio ethanolCEES
0
20000000
40000000
60000000
80000000
100000000
120000000
140000000
160000000
180000000
Mas
s Sp
ec (C
ount
s)
Depletion of CEESFormation of Products
(CEES-OH)(CEES=O)
Oxidation
Dehalogenation
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
0.50 1.00 1.50 2.00 2.50 3.00 3.500
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
110000
120000
130000
140000
150000
Time-->
2.12
2.24
3.06
CH2-CH2S
CH2-CH2Thiirane
SO2
ChloroethyleneCl-CH=CH2
Some Products from Oxidation Reactions of 2-CEES
Cyclization
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
NMR (HRMAS) Sample preparation
Vapor chamber for exposing catalyst to vaporous agent/simulant
SAMPLE
4 mm HRMAS rotor for examining small volumes of sample (< 100 µl)
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
1H 1D Spectra Reaction Kinetics
4.5 hrs
24.6 hrs
10.4 hrs
27.8 hrs
63.3 hrs
71.4 hrs
94.8 hrs
CEES Peaks at 2.8 and 2.6 disappear upon vapor exposure to nano-Al2O3
2.8 2.6
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Normalized 2-CEES Degradation KineticsBy Solid State NMR
0
20
40
60
80
100
0 10 20 30 40 50 60 70 80 90 100
Time (hrs)
% C
EES
Rem
aini
n
Alumina
Alumina Plus
Titania
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Rate of CEES Vapor Depletion in HRMAS NMR Studies
Rate Activity% CEES/hr mgCEES/24hr
mgNanoparticleNanoAl2O3 0.83 0.020NanoTiO2 2.3 0.094NanoAl2O3-PLUS 3.1 0.74*
*30 g/m2 of nanoAl2O3-PLUS needed to meet current protection requirements. 100 g/m2 of nanoTiO2
needed.
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
POM Catalyst Reactionswith 2-CEES
- POM on Carbon Surface- Effect of Copper Content
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
0 POM POM POM1Cu
POM2Cu
POM5Cu
POM10Cu
Diethyl sulfideEthyl vinyl Sulfide
CEES OxideEthylthio ethanol
CEES
0
2000000
4000000
6000000
8000000
10000000
12000000
14000000
16000000
18000000
Mas
s Sp
ec (C
ount
s)POM/Carbon Reduces 2-CEES
in GC/MS
New Reaction Products Found
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Reaction Product from Carbon/POM + 2-CEES
Isopropanol+Water Isopropanol
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Dimer of 2-CEES from Oxidation Reaction
SS+
Cl-
OH
Dimerization
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
CEES Vapor Diffusion Studies
Thick vs Thin SupportedSelectively Permeable Films
ReactivePVAM (polyvinyl amine-co-vinyl alcohol)
Non-ReactiveNafion, Membrane C, Membrane T
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Reactive SelectivelyPermeable Membranes
CH2 CH CH
OH NH2m n
CH2Polyvinyl alcohol-co-amine, PVA-Am
PVA-Am Film
After DFP VaporExposure
PVA-Am Film Hydrolyzes DFP, G-agent Simulant
(Seen by pH indicator).
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
0
300
600
900
1200
1500
0 0.2 0.4 0.6 0.8 1.0
Polyvinyl Alcohol / Polyvinyl Amine Copolymer(PVA-Am)
PVA-Am M6
PVA-Am M12
PVA-Am L12
PVA-Am L6Nafion (140 µm)
Expanded Polytetrafluorethylene (ePTFE)
Gore-Tex Laminate
Mean Relative Humidity
Wat
er V
apor
Diff
usio
n R
esis
tanc
e (s
/m)
High
Water VaporDiffusion Resistance
Low
(Worst)
(Best)
Water Vapor Diffusion(Thin, Supported)
(Thick)
(Thick)
(Thick)
(Thick)
(Thick)
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
12
Gore-Tex
MembraneT
MembraneC
M12
Nafion
0
2000
4000
6000
8000
10000
12000
14000W
ater
Vap
or F
lux
at 5
0% R
H (g
/m2/
da
Number of Film Layers
Water Vapor Flux of Supported Membranes
Water Vapor DiffusionThin, Supported Films
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
CEES Vapor DiffusionThin, Supported Films
3mg CEESapplied
Weatherpr
oof M
embNafi
on 1-La
yer
Nafion
3-Laye
rMem
brane T
Membran
e CM12
1-Laye
rM12
2-Laye
r
80RH50RH
0RH0
10
20
30
40
50
60
70
CEE
S Va
por P
enet
ratio
n (%
) .
80RH50RH
0RH
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Conclusions
Chloramide-treated fabrics break down 2-CEES in solution and in vapor challenge tests.
One of the major by-products was the nontoxic sulfoxide. Other by-products include dimers.
Chloramides bound to nanoparticles of alumina were reactive, but not as active as the chloramides alone.
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
NanoAl2O3-PLUS more adsorptive than activated carbon.
NMR found that NanoAl2O3-PLUS depleted 2-CEES at a rate of 0.74 mgCEES/mgNanoparticle/day.
A fabric weight of 1-33 grams per square meter of NanoAl2O3-PLUS needed to meet the 1mg/cm2/day protection requirement for clothing systems.
100 gsm of nanoTiO2 would be needed for protective fabrics to meet Chemical Protection requirements.
Conclusions
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Conclusions
Carbon-bound POMs faster than free POM in the decomposition of 2-CEES.
Carbon-bound POMs can be optimized with Cu to increase depletion of 2-CEES by 7x.
Copper-containing POMs completely neutralize 2-CEES in 30 min. Produce CEES-oxide (sulfoxide) product.
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Conclusions
Thin supported PVAM films have high water vapor permeation, similar to commerical permselectivemembranes C and T.
Thin supported Nafion has the highest water vapor permeation.
Thin supported Nafion and MembraneC allow CEES penetration above 50RH
Thin supported PVAM films and MembraneT block CEES below 80RH.
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
Reactive Fabric System Design
SHELL
QuaternaryAmine on TopSporicide Water-Repellent
ChloramideUnderneathBio, HD & VX
Reactive Permselective Liner
Nanoparticle “sandwich”
Carbon-Nylon Tricot Knit Scrim
U.S. Army Research, Development & Engineering Command Natick Soldier Center, • Natick, MA
AcknowledgementsProfessor Craig Hill and Dr. Nelya Okun, Emory
University for POM Catalysts
Gentex Corporation for spherical carbon
Reactive Materials Team at Tyndall AFBFor Chloramides & Test Data
Edgewood NMR Group for MAS Results
Erkol, Ltd. for PVAM Polymers
Phil Gibson, Joel Carlson, John Walker at Natick