nanoprotective garments

Serving Customer Needs Through Advanced Chemistrywww.NanoScaleCorp.com

ACS Spring 2010 National Meeting and Exposition, March 22, 2010

Shyamala Rajagopalan, Ph.D.Manager, Research & Project Development

NanoScale Corporation, Manhattan, KS

From Nanoparticles to Novel Protective Garments

Sponsored by : NIOSH

Phase II SBIR: Grant No. 2R44OH007963-02A2

Serving Customer Needs Through Advanced Chemistry

• Goal of the Project• Current Technology and Its

Limitations• Project Work Plan• Project Progress• Acknowledgements

Presentation Outline

carbon vs nano


Project Goal and Envisioned Product

• Protective

• Lightweight

• Air-permeable

• Comfortable

Prepare and test materials for clothing to protect against chemical

hazards.


Available Technology• Impermeable materials.

Generally made of rubber or neoprene or other elastomers Heavy and bulky Hot due to lack of air and water vapor permeability Uncomfortable to wear Ex: OSHA approved Level A suit

• Air-permeable materials. Shell fabric; a layer of sorptive material; a liner fabric Low physical burden High water vapor permeability Protection can be low in some instances Ex: JSLIST suit

• Semi-permeable materials. Porous and solution-diffusion membranes Ex: Gore-Tex

• Selectively permeable materials. Thin, lightweight, layered, and flexible Ex: US Army NSC; Gore-Tex; DuPont

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Current Technology - Limitations• Protective textiles based on carbon

materials need REAL enhancement.• Only PARTIAL PROTECTION is

afforded by activated carbon through physical entrapment of toxins.

• Activated carbon DOES NOT NEUTRALIZE adsorbed chemicals; it simply stores them.

• Preferential adsorption of water by carbons or increase in temperature results in OFF-GASSING of adsorbed toxins.

• Untreated carbon has LITTLE EFFECT UPON ACID OR ALKALINE GASES.

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Targeted Laminate Properties

• Weight reduction is targeted to come from the fabric/adhesive.

• Effect of sorbent on the textile’s air permeability is unknown.

• Sorbent immobilization protocol on the textile will also play a critical role in the laminate’s properties.


PropertyCarbon

Bead Laminate

NanoScale Proposed Laminate

Total weight (g/m2) 402 350

Sorbent:Fabric weight (g) 250:152 250:100

Air Permeability (cm3/cm2.s)

63 >63


Project Work PlanTask 1Preparation of granulated mixed nanoparticlesMonth 1 - Month 4

Task 2Performance evaluation and down selectionMonth 1 - Month 5

Task 3Textile/nanoparticle integrationMonth 3 - Month 11

Task 4Permeation testingMonth 6 - Month 12

Task 6Prototype productionMonth 18 - Month 24

Task 5Scale-up studiesMonth 13 - Month 17


Air Filtration Test Apparatus


Compressed Air

Water

SorbentTest Bed

FT-IR w/16 m Gas Cell

Challenge

Agent

Vent to

Hood

Humidity Controller

• Goal is to screen sorbents for initial downselection.

• Challenge and breakthrough concentrations are based on OSHA PEL/IDLH.

Breakthrough Test Results

• Breakthrough time in minutes. • Average of 3 trials.• Single metal oxides.• Bi-metal oxides.• Tri-metal oxides.


Sample NH3 HCN 2-CEES Sample NH3 HCN 2-CEES

1 5.5 17 21 8 5.5 54 19

2 6.9 20 32 9 7.3 25 24

3 7.3 71 29 10 5.0 12 23

4 5.5 1.0 12 11 43 6.5 61

5 7.3 52 41 12 34 22 36

6 3.0 >180 3.0 13 27 30 38

7 6.5 49 28 14 21 45 34

Commercial 31 6.0 29

Downselected Formulation• One nano material formulation was

downselected and optimized based on breakthrough test results.

• Granules based on downselected formulation have ≥70% Ball Pan Hardness.

• No binders were required to harden the granules.

• Used granule sizes: -60+120, -60+80 and -40+60 mesh.


Health Effects and Safety• Acute toxicology testing done at the U.S. Army’s Center for Health

Promotion and Preventative Medicine (USACHPPM) under GLP.– NanoActive materials are no more toxic than their commercial

counterparts Several materials have been tested.– Sub-chronic toxicology testing showed no detrimental effects (FAST-

ACT).• Human immune cell testing by Prof. Paul Wright, Toxicology Unit,

School of Medical Sciences RMIT in Melbourne, Australia.– No cytotoxicity to human immune cells in this study (FAST-ACT).

• Dermal penetration study by Dr. Deon van der Merwe, Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS.– No penetration of intact human skin (FAST-ACT).

• Lung effect study by Dr. John Pickrell, Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS.– No lasting detrimental effects (FAST-ACT).



Permeation Set Up – Initial Test

Vessel + Comfort Layer

Vessel + Comfort Layer + Sorbent

Vessel + Comfort Layer + Sorbent + Black Liner +

Cover Fabric

Vessel + Comfort Layer + Sorbent + Black Liner

Complete Permeation Test Set Up

• For DMMP testing: Water in inner vessel.

• For 2-CEES testing: Carbon beads in inner vessel and water in outer jar.

Laminated Carbon Fabric -Key Points

• A single layer of carbon beads is glued between black silk and comfort layers.

• Adhesive Web Glue Sheet is used in the gluing of the carbon beads.

• Fabric is stiff.

• Fabric is slightly breathable.

• Adhesive Web Glue Sheet also helps to contain the contaminant.

• No agent permeation was seen.

• No agent was seen on the cover fabric.

• Solvent extraction showed intact agents from the laminate.


Sample2-CEES,

%DMMP, %

Permeated 0 0

Extracted from the laminate

100 97


ASTM F739:Fabric Permeation Testing• ASTM F739 is designed to measure the permeation of liquids or gases under

conditions of continuous contact: Liquid agents are tested in the closed top/open loop configuration. Gaseous agents are tested in the open top/open loop configuration.


NFPA Standard Testing Conditions• Liquid agent.

Chamber temperature at 32˚ C (±3˚ C). Relative humidity of 80% (±5%). Collection gas flow at 1 LPM.

• Gaseous agents are tested under the same conditions with the gas flowing at 1 LPM through the challenge side.

• Tests are run for 1h.• Select fabric samples were further extracted for retained

chemicals and byproducts.

Liquid2 CEES (HD simulant)

DMMP (GD simulant)

GasHCN

NH3

Reactive Liner - 2- LayersKey Points:• Granules were well immobilized.• No shedding was observed.

Challenges:• Weighs 442 g/m2. • Stiff.• Air permeability: 6.12 cm3/cm2.s.• Did not meet requirements of a Class 2 Protective

Garment.

Interfacing I

Adhesive Sheet A

Nano Material

Adhesive Sheet A

Interfacing I

Heat Bond Fleece

Nano Material

Heat Bond Fleece

Key Points:• Weighs 338 g/m2.• Air permeation: 57 cm3/cm2.s.• Granules were well immobilized.• No shedding was observed.• More flexible.• Passed permeation tests as Class 2 protective

garment.Challenges:• Problems with locating the same fabric. • Little stiffer than the carbon bead laminate.


2nd Reactive Liner

1st Reactive Liner

Reactive Liner – 3 - LayersKey Points:• Laminate weighs 377 g/m2.• Air permeability 71.9 cm3/cm2/s.• Passes Class 2 Protective Garment requirements.Challenges:• Laminate weight.• Mobile granules. • Granules are smaller than the pore size of the

interfacing.• Shedding is an issue.• Manufacturability of a 3-layer configuration.

Interfacing I

Nano Material

Fleece 1 with Spray Adhesive D on both sides

Nano Material

Interfacing I

Interfacing I

Nano Material & Powder Adhesive B

Fleece 1

Nano Material & Powder Adhesive B

Interfacing I

Key Points: • Weight: 387 g/m2

• Air Permeability: 73 cm3/cm2/s.• Granules fairly well secured, very minimal

shedding. • Passes as a Class 2 protective garment.

Challenges:• Laminate weight.• Manufacturability of a 3-layer configuration.


1st Reactive Liner

2nd Reactive Liner


Products from Agent Chemisorption


Permeation Test Samples from 2-CEES Experiments

Samples(% Extracted)

2-CEES (% Permeated)

2-CEES EVS HEES

Non-Laminated carbonTextile (commercial) <1 0 0

4.7Sorbent 85 0 0

Non-Laminated Nano sorbent

Textile (commercial) 0 0 046

Sorbent <1 <1 4

Laminated carbon Textile (commercial) 92 0 0 6.1

Laminated carbon Textile (NanoScale) 86 0 0 0

Laminated Nano sorbent Textile (NanoScale) <1 <1 27 1.4

Protocol • Loose sorbent was separated from textile and extracted with ethyl ether .• Separated textile was extracted with ethyl ether .• Laminated swatch containing sorbent was extracted as whole with ethyl ether .• All samples were analyzed by GC-FPD.

Outcome

Conclusions• Commercial textile (non-laminated) did not trap any 2-CEES or by-products.

• Textile (Commercial & NanoScale) containing carbons only physisorbs 2-CEES.

• NanoActive material containing swatch provided the least amount of extractable 2-CEES.

• Lamination is critical to reduce permeation.

• Destructive adsorption by nano materials was confirmed .


Permeation Test Samples from DMMP Experiments

Samples DMMP (% Extracted)

DMMP (% Permeated)

Laminated control (no sorbent) Textile (Commercial)

10 69

Laminated control (no sorbent) Textile (NanoScale)

7 54

Laminated carbon Textile (Commercial) 85 0

Laminated carbon Textile (NanoScale) 78 0

Laminated Nano sorbent Textile (NanoScale) 20 0

Protocol

• Laminated control was extracted with ethyl ether.

• Laminated swatch containing sorbent was extracted with ethyl ether.

• All samples were analyzed by GC-FPD.

Outcome

Conclusions• Laminated textile controls (no sorbent) contained low amounts of extractable DMMP with high

permeation.• Carbon containing textile swatches yielded large amount of extractable DMMP with low permeation.• NanoActive material containing textile swatches yielded the least amount of extractable DMMP with

low permeation. • By-product characterization is in progress.• Agent exposure threat is lower with nano materials containing textiles.

Attestation of Agent - Sorbent Interaction

Agent SorbentTemperature Range

(onset to conclusion,°C)

2-CEESCarbon 179-345

NanoScale sorbent 270-360

DMMPCarbon 170-320

NanoScale sorbent 285-370

Protocol• Carbon and nano formulation were challenged against CWA simulants 2-CEES and

DMMP.

• Samples were analyzed using TGA up to 600°C (10°C/min heating rate).

• Temperature at which agent off-gassing from sorbent was recorded as reflection of binding strength.

Conclusions:

NanoScale sorbent exhibited higher binding strength than carbon for 2-CEES and DMMP as reflected by higher onset and conclusion temperatures.


Where are We Now?

• Defining overall product concept/clothing system (classification by design, performance, and service life etc.).

• Defining market needs and identification of user needs (fire fighters, first responders, war fighters, drug raid, agriculture workers, chemical labs etc.).

• Performance and cost.


PropertyCarbon Bead

Laminate

Reactive Liner-2-Layer

Reactive Liner-3-Layer

NanoScale

Proposed Fabric

Total Weight (g/m2) 402 338 387 350

Sorbent:Fabric Weight (g)

250:152 250:88 250:137 250:100

Air Permeability (cm3/cm2.s)

63 57 73 >63


Acknowledgements

Team Members at NanoScale Corp.Chris Aikens

Shuvo Alam

Dennis Karote

Jane Langemeier

Cherry Leaym

Justin Millette

NIH/CDC/NIOSH

Fabric Suppliers

nanoprotective garments

Documents

customer needs

project progress

advanced chemistryproject

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advanced chemistryacs

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test materialsfor clothing

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