Dispersed CNT in BA based latex (sphere 200 nm) Carbon nanotube - - PowerPoint PPT Presentation

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Dispersed CNT in BA based latex (sphere 200 nm) Carbon nanotube decorated poly(methyl methacrylate) microbeads Double percolation of CNT and n-Pani

• J. Lu, J.F. Feller, B. Kumar, M. Castro, Y.S. Kim, Y.T. Park and J.C. Grunlan, « Chemo-sensitivity of latex-based films containing segregated networks of carbon nanotubes « , Sensors and Actuators B:

Chemical B 155 (2011) 28–36.

• J. Lu, B. J. Park, B. Kumar, M. Castro, H. J. Choi and J-F. Feller, « Polyaniline nanoparticle–carbon nanotube hybrid network vapour sensors with switchable chemo-electrical polarity « ,

Nanotechnology, 21, 255501 (2010) J-F Feller, J. Lu, K. Zhang, B. Kumar, M. Castro, N. Gatt, H.J. Choi , « Novel architecture of carbon nanotube decorated poly(methyl methacrylate) microbead vapour sensors assembled by spray layer by layer « , Journal of Materials Chemistry, 2011, 21, 4142.

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107-109

t

Percolation Percolation

Transition Insulator / Conductor ρCPC = ρ f Φ − Φ c

( )

−t

threshold threshold Filler content φ (%)

10-1- 102 Φc

First step: establishing percolation curve of CPC, which depends on intrinsic components properties (aspect ratio, interaction,

conductivity ) and processing conditions (shear rate temperature viscosity ) conductivity…) and processing conditions (shear rate, temperature, viscosity…)

Second step: selecting level of conductivity to reach best compromise between sensitivity / stability for different external

sollicitation (chemical, mechanical, heat) (just above percolation threshold) ( , , ) (j p )

J-F. Feller, M. Castro and B. Kumar, « Polymer carbon nanotube conductive nanocomposites for sensing« , in Polymer carbon nanotube composites: Preparation, properties and applications, Edited by T McNally, Queen’s University Belfast, UK and P Pötschke, Leibniz-Institut für Polymerforschung Dresden e.V. (Leibniz Institute of Polymer Research Dresden), Germany, ISBN 1 84569 761 8, ISBN-13: 978 1 84569 761 7, Q1 2011, 750 pages

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Layer by Layer Spray technique offers the opportunity to finely control the 3D architecture of the conductive structure via adjustable parameters (concentration, number of layers, CPC/solvent interaction) Furthermore this technique offers great versatility to match with several kind of external sollicitationation

KUMAR B., LU J., CASTRO M., FELLER J. F.* , « Conductive bio-Polymer nano-Composites (CPC): Chitosan-carbon nanotube transducers assembled via spray layer by layer for volatile organic compound sensing « ,Talanta, Volume 81, Issue 3, 908-915 (2010).

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PS-CNP

500 µm 500 µm 10 µm 30 µm 30 µm

PC-CNT

1 µm

PS-CNP films assembled onto interpenetrated electrodes by sLbL lead to high specific surface transducers hi h b t il d ith PS d CNP t t

200 nm

which can be tailored with PS and CNP structure PC-CNT microdroplets weld during assembly. PC helps structuring CNT network together and brings chemical specificity

FELLER J. F.* , GROHENS Y., « Electrical response of Poly(styrene)/carbon black conductive polymer composites (CPC) to methanol, toluene, chloroform and styrene vapors as a function of filler nature and matrix tacticity « , Synthetic Metals, 154, 1-3, 193-196 (2005). LU J., KUMAR B., CASTRO M., FELLER J. F.* , « Vapour sensing with conductive polymer nanocomposites (CPC): Polycarbonate-carbon nanotubes transducers with hierarchical structure processed by spray layer by layer « ,Sensors & Actuators B: Chemical, 140, 451-460 (2009)

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• N. S. Lewis, Accounts of Chemical Research, 37, 9, 663-672 (2004)
• G. Peng, E. Trock, H. Haick, Nano Lett. 2008, 8 (11), pp 3631–3635

Toluene Ethanol Chloroform Water Methanol THF

CPC sensor matrix Signal processing Data Analysis Pattern recognition Volatile Organic Compounds

Responses from non-specific sensor are analyzed in parallel Summarized results are then further compiled using Principal Component Analysis to get fingerprint of tested vapours Sensitivity, selectivity and reproducibility are still important challenges

• M. Castro, B. Kumar, J. F. Feller, Z. Haddi, A. Amari, B. Bouchikhi, « Novel e-nose for the discrimination of volatile organic biomarkers with an array of carbon nanotube (CNT) conductive polymer

nanocomposite (CPC) sensors « , Sensors and Actuators B: Chemical, 2011, Vol. 159, Issue 1, 213-219.

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m)

ρ resistivity, a and b constant and Z distance between two particles

tivité (Ω.cm Résist

PVC Effect [Vapour] CPC are composites materials which are sensitive to inter-particles distance Electrons can go through the conductive network by tunelling effect Electrons can go through the conductive network by tunelling effect

FELLER J. F.* , GROHENS Y., « Evolution of electrical properties of some conductive polymer composite textiles with organic solvent vapours diffusion .« , Sensors & Actuators B: Chemical, 97, 2-3, 231- 242 (2004).

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Model LHC

de Langmuir adsorption Henry diffusion se amplitud Clustering Ar respon f’ f’’

( )

' L L

. ' . .f) b (1 f).f ' .(f' b

n H r

f f f f k A − + + + − =

φ vapour % bL Langmuir affinity constant, f solvent fraction, f’ solvent fraction when clustering occurs, f solvent fraction when Langmuir is replaced by Henry diffusion, kH Henry solubility coefficient (slope of 2nd region in the curve). In φ vapour % g p y y

H

y y ( p g ) the third region, AR (or Δm/m) increases exponentially, n’ is the average number of water molecule within cluster. This acceleration comes from solvation of the polymer matrix which enhance the solubility of the penetrant molecules.

LU J., KUMAR B., CASTRO M., FELLER J. F.* , « Vapour sensing with conductive polymer nanocomposites (CPC): Polycarbonate-carbon nanotubes transducers with hierarchical structure processed by spray layer by layer « ,Sensors & Actuators B: Chemical, 140, 451-460 (2009)

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8 10

PCLc+PCL-g-1% CNT PCLc-1% CNT PCL-g-1% CNT

Toluene vapour

6 8

PCLs-1% CNT

AR

2 4

A

900 1800 2700 3600 4500

Time/ s Ring Opening Polymerization of ε-caprolacton on CNT, induces both better dispersion and higher compatibility with PCL matrix. PCL-grafted-CNT also induces an increase in chemo-electrical response

CASTRO M., LU J., BRUZAUD S., KUMAR B., FELLER J. F.* , « Carbon nanotube/poly(e-caprolactone) composite vapour sensors « , Carbon, 47, 1930-1942 (2009).

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Relative resistance amplitude is in good agreement with reciprocal interaction parameter χ12

With a and b constants

(Flory Huggins) This could help optimizing the selection of CPC sensor by predicting their selectivity if assembled in electronic nose

KUMAR B., LU J., CASTRO M., FELLER J. F.* , « Conductive bio-Polymer nano-Composites (CPC): Chitosan-carbon nanotube transducers assembled via spray layer by layer for volatile organic compound sensing « ,Talanta, Volume 81, Issue 3, 908-915 (2010).

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• Depending on the formulation, the CPC micro-fibers allow the detection of a specific temperature (boy temperature 35°C, or

p g p p ( y p pain yield temperature 55°C)

• Very encourageing results have been obtained during the Inteltex European Project.

J-F. Feller, M. Castro and B. Kumar, « Polymer carbon nanotube conductive nanocomposites for sensing« , in Polymer carbon nanotube composites: Preparation, properties and applications, Edited by T McNally, Queen’s University Belfast, UK and P Pötschke, Leibniz-Institut für Polymerforschung Dresden e.V. (Leibniz Institute of Polymer Research Dresden), Germany, ISBN 1 84569 761 8, ISBN-13: 978 1 84569 761 7, Q1 2011, 750 pages

Part fixed in l (20

12

clamps (20 mm) Efficient CPC Wire connection Length (100 mm) Efficient CPC gauge (20 mm) Wire connection (2.5 mm) Width (10 mm)

12 14

)

2 2,5

%)

Résistance relative (%) deformation (%)

6 8 10

ésistance ative (%)

1 1,5

rmation (%

2 4

Ré rel

0,5

defor

200 400 600 800

Temps (s)

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M déli ti d t f t d h l t d l diff i d

• Modélisation des transferts de chaleur et de la diffusion des

petites molécules dans les systèmes hétérogènes CPC -> couplage électrique O ti i ti d hit t CPC l i i d té t d

• Optimisation des architecture CPC pour le suivi de santé et de

déformation dans les structures composites

• Nouvelle architectures micro/nano pour les nez électroniques

dédiés au diagnostique précoce des maladies par l’analyse de l’haleine (cancer du poumon …)

• Utilisation

des senseurs CPC pour la caractérisation des performances barrières de films obtenus pas LbL électrostatique p p q