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Defence R&D Canada
DEFENCE DÉFENSE&
Synthesis and Characterization of Polyaniline –Carbon
Nanostructure CompositesPreliminary Experiments
Trisha A. HuberDRDC Atlantic
Mary N. DiepDRA – University of Waterloo
Technical Memorandum
DRDC Atlantic TM 2003-206
October 2003
Copy No.________
Defence Research andDevelopment Canada
Recherche et développementpour la défense Canada
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Copy No: _________
Synthesis and Characterization of Polyaniline – Carbon
Nanostructure Composites Preliminary Experiments
Trisha A. Huber DRDC Atlantic
Mary N. Diep DRA – University of Waterloo
Defence R&D Canada Atlantic Technical Memorandum DRDC
Atlantic TM 2003-206 October 2003
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Abstract Recent years have seen much progress in the area of
electronic materials, especially carbon nanostructures (nanofibers
and nanotubes) and conducting polymers. There is evidence in the
literature that a composite, marrying these relatively new
materials, exhibits exceptional properties relative to the parent
materials. We have synthesized composites comprised of polyaniline
and carbon nanostructures by a number a methods. The composites
were subject to electronic characterization in order to assess
whether the presence of both types of materials results in any
electronic synergism. The results will be presented.
Résumé
Les dernières années ont vu beaucoup de progrès dans le secteur
des matériaux électroniques, en particulier les nanostructures
(nanofibres et nanotubes) et des polymères conducteurs. La
littérature semble prouver qu’un composite associant ces matériaux
relativement nouveaux présente des propriétés exceptionnelles par
rapport aux matériaux parents. Nous avons synthétisé par un certain
nombre de méthodes des composites comprenant des nanostructures de
polyaniline et de carbone. Les composites étaient soumis à une
caractérisation électronique afin de déterminer si la présence des
deux types de matériau produisait une synergie électronique. Les
résultats sont présentés.
DRDC Atlantic TM 2003-206 i
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ii DRDC Atlantic TM 2003-206
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Executive summary
Introduction
Two relatively new materials, carbon nanotubes and conducting
polymers, have been the focus of much research of late. Interest in
these materials is largely due to their electrical conductivity,
although the nanotubes are also the focus of many structural
studies as a result of their mechanical strength. Although they
both exhibit good electrical properties, each one also possesses
shortcomings. A composite promises to be interesting as the
strengths of each are complementary. Most notably, the mechanical
strength and thermal properties of the carbon may help to improve
the strength and environmental integrity of the conducting
polymers. In addition, the aggregation tendency and poor matrix
adhesion of the carbon, may be addressed by the presence of the
polymer.
Results
Polyaniline-carbon nanotube and polyaniline-carbon nanofibre
composites have been prepared and the electrical conductivity
measured. The composite conductivity values exhibit an enhancement
over that of the parent materials.
Significance
The existence of a conductivity enhancement, in addition to
improvement in environmental stability and mechanical properties,
yields a composite that is greater than the sum of its parts. Such
a composite would be of use in many areas that currently use
conventional electrically conducting species (electrical
components, displays, rechargeable batteries, sensors, etc.).
Future Plans
Further work into the preparation of these composites, as well
as investigation into the nature of the conductivity enhancement is
planned.
Huber, T.A., Diep, M.N.. 2003. Synthesis and Characterization of
Polyaniline – Carbon Nanostructure Composites. DRDC Atlantic TM
2003-206.
DRDC Atlantic TM 2003-206 iii
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Sommaire
Introduction
Deux matériaux relativement nouveaux, les nanotubes du carbone
et les polymères conducteurs, ont constitué l’objet principal de
beaucoup de recherches ces derniers temps. C’est leur conductivité
électrique qui a attiré en grande partie l’intérêt sur ces
matériaux. Ils présentent tous les deux de bonnes propriétés
électriques, mais ils ont aussi chacun des défauts. Un composite
promet d’être intéressant puisque les résistances de chacun des
matériaux se complémentent. À noter en particulier que les
propriétés mécaniques et thermiques du carbone peuvent contribuer à
améliorer la résistance et l’intégrité environnementale des
polymères conducteurs. De son côté, la présence du polymère peut
traiter la tendance du carbone à l’agrégation et la faible adhésion
à la matrice de celui-ci.
Résultats
Nous avons préparé des composites, nanotube polyaniline-carbone
et nanofibre polyaniline-carbone, et mesuré leur conductivité
électrique. Les valeurs de conductivité des composites présentent
une amélioration par rapport à celles des matériaux parents.
Importance
Une conductivité accrue, renchérie par une stabilité
environnementale et des propriétés mécaniques renforcées, rend un
composite supérieur à la somme de ses éléments. Ce composite serait
utile dans beaucoup de secteurs où l’on utilise actuellement les
genres de conducteurs électriques conventionnels (composants
électriques, visualisation électrique, piles électriques
rechargeables, capteurs électriques, etc.)
Futurs plans
Nous envisageons de continuer à travailler à la préparation de
ces composites ainsi qu’à fouiller la nature de l’amélioration de
la conductivité.
Huber, T.A., Diep, M.N.. 2003. Synthesis and Characterization of
Polyaniline – Carbon Nanostructure Composites. DRDC Atlantic TM
2003-206 R & D pour la défense Canada – Atlantique.
iv DRDC Atlantic TM 2003-206
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Table of contents
Abstract........................................................................................................................................
i
Résumé
........................................................................................................................................
i
Executive summary
...................................................................................................................
iii
Sommaire...................................................................................................................................
iv
Table of contents
........................................................................................................................
v
List of figures
............................................................................................................................
vi
List of tables
..............................................................................................................................
vi
Introduction
................................................................................................................................
1
Experimental...............................................................................................................................
2 Method I (bulk
solution)................................................................................................
2 Method II (isolation of
solid).........................................................................................
2
Results and Discussion
...............................................................................................................
3 Polyaniline – Nanotube (PAni/DBSA/NT) Composites – Method
I............................. 3 Polyaniline – Nanotube
(PAni/DBSA/NT) Composites – Method II............................ 4
Polyaniline – Nanotube (PAni/DBSA/NT) Composites – Ex-Situ
................................ 5 Polyaniline – Nanofiber
(PAni/DBSA/CNF) Composites – Method I.......................... 5
Polyaniline – Nanofiber (PAni/DBSA/CNF) Composites – Method II
........................ 7 Polyaniline – Nanofiber (PAni/DBSA/CNF)
Composites – Ex-Situ............................. 9
Conclusion................................................................................................................................
11
References
................................................................................................................................
12
List of symbols/abbreviations/acronyms/initialisms
................................................................
13
Distribution list
.........................................................................................................................
14
DRDC Atlantic TM 2003-206 v
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List of figures
Figure 1. A Plot of Conductivity as a Function of Nanotube
Content........................................ 4
Figure 2. A Plot of Composite Conductivity Versus Wt % Carbon
Nanofibers ........................ 6
List of tables
Table 1. Conductivity Data of PAni/DBSA/NT Composites (Method
I)................................... 3
Table 2. Conductivity Data of PAni/DBSA/CNF
Composites................................................... 6
Table 3. Conductivity and Yield Data for PAni/DBSA/CNF
composites (Method II – variable
CNF)....................................................................................................................................
8
Table 4. Conductivity and Yield Data for PAni/DBSA/CNF
composites (Method II – variable
aniline).................................................................................................................................
9
Table5. Conductivity and Content of Isolated Solid
................................................................
10
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Introduction
Carbon nanotubes and conducting polymers have been the focus of
much research in the last decade or so. The former have been the
subject of much scrutiny due to their extraordinary electrical and
mechanical properties, and the latter because of their exceptional
electrical properties. Both materials have been investigated for
their potential as electronic or optical devices.
Despite their exceptional properties, each material has
shortcomings. Carbon nanotubes are expensive, exhibit poor matrix
adhesion, and tend to aggregate, which makes processing
challenging. Conducting polymers exhibit poor mechanical
properties, and are subject to environmental degradation over
time.
A composite made up of these two materials would be highly
interesting, as the shortcomings of one material may be addressed
by the presence of the other. Coating the nanotubes with a
conducting polymer should reduce the degree of aggregation, thus
improve matrix adhesion and processibility. Moreover, conducting
polymers are far more economical to produce, thereby reducing the
overall cost per device, or per unit mass. The presence of carbon
nanotubes in such a composite would likely improve mechanical
properties, due to their high strength, as well as help to maintain
the integrity of the composite due to their thermal strength and
potential antioxidant behaviour.
Over and above the potential mutually beneficial outcome, there
have been reports of interesting electronic interaction between
these two materials [1-4]. In addition to reports of potential
electronic synergy, there are other findings that suggest that
there is no electronic interaction between conducting polymers and
nanotubes [5-7].
In this paper we report the preparation and characterization of
both polyaniline-carbon nanotube and polyaniline-carbon nanofiber
composites. The composites were prepared by both in-situ
polymerization (aniline was polymerized in the presence of the
nanostructure) and ex-situ polymerization (the nanostructure was
mixed with the pre-formed polyaniline). In an effort to investigate
the discrepancy in the literature, the electronic properties of the
composites were probed by measuring the conductivity of the bulk
product.
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Experimental
Aniline (Aldrich, > 99.5%) was distilled under vacuum before
use; dodecylbenzenesulfonic acid (DBSA) (Aldrich, 70 wt% solution
in 2-propanol), multiwalled nanotubes (Aldrich, > 95%), toluene
(Aldrich, > 99.5 %), and ammonium persulfate (APS) (Fisher
Scientific, 99%) were used as received. The carbon nanofibers
(Pyrograf III carbon fibers, grade PR-24-PS-LD) were ball-milled
before use.
Conductivity of pressed pellets (13 mm diameter, 8 tons,
thickness ca. 1 mm) was performed using the four-point probe
method.
The polyaniline – nanostructure composites were prepared by both
in-situ and ex-situ polymerization. For both the nanotube and the
nanofiber composites, the products were prepared in toluene
solution containing DBSA (0.06 M), but two slightly different
methods for isolation were employed (vide infra). The ex-situ
polymerization simply consists of sonicating the carbon
nanostructures in a toluene solution of PAni/DBSA, followed by
stirring overnight.
Method I (bulk solution)
In one set of in-situ experiments, the nanotubes were dispersed
in toluene containing aniline by high frequency, low power
sonication (12W, 55kHz) for approximately two hours. The APS was
dissolved in ~ 10 mL of water and slowly added dropwise to the
toluene suspension with stirring. After addition was complete the
reaction was allowed to stir overnight to ensure completion of
reaction. The reaction mixture was transferred to a separatory
funnel, and the organic layer was washed twice with ~ 20 mL of a
1:1 acetone:water mixture in order to remove excess DBSA and
reaction by-products. The toluene was allowed to evaporate from the
organic layer (which contains the nanostructures and PAni/DBSA).
The residue was then washed with ethanol, and dried in vacuo at
room temperature for at least 24 hours. After drying, conductivity
measurements were performed on pressed pellets of the product.
Method II (isolation of solid)
This method is similar to Method I up to and including washing
the organic layer with the acetone:water mixture. After washing,
the organic layer was filtered through a track-etched polycarbonate
membrane (Millipore, 0.2 micron diameter pores) to collect the
solid; the toluene was allowed to evaporate from the filtrate, and
the residue was washed, and dried as above.
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Results and Discussion
Polyaniline – Nanotube (PAni/DBSA/NT) Composites – Method I
For the nanotube experiments, the only variable was the quantity
of nanotubes added; all other parameters were constant. Most
nanotube experiments were performed according to Method I; the
solids obtained from the organic layer were obtained by evaporation
of the toluene after washing – these data are denoted by the use of
the term bulk solution. The conductivity data for the bulk solution
composites are presented in Table 1. The quoted weight % nanotubes
(wt % NT) is based on the mass of nanotubes relative to the total
mass of aniline and nanotube; the actual weight % nanotubes has not
yet been determined, but thermogravimetric analysis (TGA) may be
used to obtain a more accurate value of nanotube content.
Table 1. Conductivity Data of PAni/DBSA/NT Composites (Method
I)
Mass NT (mg) Wt % NT‡ Conductivity (S/cm)
0 0 0.34
25 4.6 0.62
51 9.1 1.5
100 16 6.3
‡ (mass NT/(mass NT + mass of aniline))x100%
Due to the cost of nanotubes and the desire to use nanotubes
from the same batch, replicate experiments were not performed.
Although these are preliminary results, it is evident that the
conductivity of the composites increases with increasing nanotube
content (see Figure 1). The sudden increase in conductivity at 20
wt% nanotubes might indicate that this system is consistent with
percolation theory, in which a highly conducting species is
distributed within a matrix. Generally, percolation theory applies
to a highly conducting species dispersed in a nonconductive matrix,
however in this case, the PAni/DBSA would be considered to be the
matrix, and is conductive, albeit, less so than the highly
conducting species. It is reasonable to assume that the highly
conductive species could simply be nanotubes dispersed throughout a
matrix of PAni/DBSA, however, other results indicate that the
highly conducting species is more complex (vide infra).
DRDC Atlantic TM 2003-206 3
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0
4
8
12
16
20
0 20 40 60 80 100Wt % NT
Con
duct
ivity
(S/c
m)
Figure 1. A Plot of Conductivity as a Function of Nanotube
Content
Polyaniline – Nanotube (PAni/DBSA/NT) Composites – Method II
Polyaniline doped with DBSA (PAni/DBSA) is soluble to a certain
extent in toluene, thus the reaction mixture is a very dark green.
It was thought that if the polyaniline interacted with the
nanostructures, that perhaps the polyaniline – nanostructure
complex would be soluble to some extent. This is not unreasonable,
as there is evidence in the literature for
poly(m-phenylene-co-2,5-dioctoxy-p-phenylenevinylene (PmPV), which
is a conjugated polymer, wrapping around nanotubes, and effectively
solubilizing them in toluene [8]. In order to employ spectroscopy
to investigate any potential electronic interaction, UV-visible
spectra were acquired of the various nanotube weight % reaction
mixtures, and were found to be identical to the spectrum of
PAni/DBSA produced in the absence of carbon nanotubes. Based on the
literature, it is reasonable to expect that any electronic
interaction between nanotubes and polyaniline would be evident in
the ultraviolet-visible (UV-vis) spectrum [9-11]. The absence of
new charge-transfer bands indicate that the PAni/DBSA is either not
soluble enough in toluene to solubilize the nanotubes, or the
PAni/DBSA does not interact well enough with the nanotubes to
effect solubilization. Filtration of the very dark green reaction
mixture revealed the presence of solid (hence the use of the Method
II workup), which was
4 DRDC Atlantic TM 2003-206
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washed and dried as above. The mass of the isolated solid was
found to exceed that of the nanotubes used in the reaction,
indicating the presence of polyaniline, in addition to the
nanotubes. At this point, it was not clear whether the solid was
simply a mixture of nanotubes and polyaniline, or whether the
polymer was interacting with the nanotubes.
The nature of the interaction between the nanotubes and the
polyaniline became clearer upon measurement of the conductivity of
the isolated solid. It is reasonable to assume that the composite
conductivity would increase as the nanotube content increases, and
approach that of the pure nanotubes. However, the conductivity of
the solid significantly exceeded that of the pure nanotubes; the
conductivity of the composite was measured to be 33 S/cm, whereas
the pure nanotubes exhibit a conductivity of 17 S/cm. The nature of
this extraordinary increase is not yet clear, although these data
suggest that the polyaniline and the nanotubes do indeed interact.
This experiment was repeated, and the conductivity of the isolated
solid was found to be 36 S/cm.
Polyaniline – Nanotube (PAni/DBSA/NT) Composites – Ex-Situ
A solution of PAni/DBSA prepared in the absence of any carbon
nanostructures, then sonicated and stirred in the presence of the
nanotubes (~ 10 wt.%), was filtered. The solid isolated from the
mixture was dried in vacuo, and the yield was determined to greatly
exceed the amount of nanotubes used. The conductivity of a pressed
pellet was found to be 7.3 S/cm, which is higher than the 10 wt%
composite made by Method I (bulk solution, 1.5 S/cm), but much
lower than that made by Method II (isolated solid, ~ 34 S/cm). It
would appear that the in-situ polymerization yields a more
conductive product – this may be attributable to better interaction
between the polymer and the nanotubes, due to pre-polymerization
monomer – nanotube adsorption, or perhaps more favourable polymer
morphology. The origin of these differences will be subject to
further study.
Polyaniline – Nanofiber (PAni/DBSA/CNF) Composites – Method
I
The investigation with the carbon nanofibers (CNF) was carried
out more rigorously due to their lower cost, and larger batch size.
Replicate experiments in which the amount of CNF was varied
relative to aniline, and vice versa were performed.
Conductivity data for the experiments involving increasing
amounts of CNF are presented in Table 2. Unlike the nanotubes,
which are much more conductive relative to PAni/DBSA (17 S/cm
versus ~ 0.3 S/cm), the conductivity of the nanofibers was measured
to be ~ 1 S/cm, which is effectively the same as the polyaniline,
within experimental error. Thus, in a simple mixture, one would not
expect to see any dramatic variation in conductivity with varying
amounts of nanofibers, however, there does appear to be a trend as
the nanofiber content increases. Conductivity as a function of
carbon nanofiber content is illustrated in Figure 2, and there is
an obvious increase as the CNF content increases. Interestingly, at
nanofiber contents equal to and greater than 30 wt%, the composite
conductivity exceeds that of the nanofibers alone, and appears to
level off at ~ 60 wt%.
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Table 2. Conductivity Data of PAni/DBSA/CNF Composites
Mass CNF (mg) Wt % CNF‡ Conductivity* (S/cm)
0 0 0.34
25 4.7 0.68
50 8.9 0.84
100 16 0.81 ± 0.17
200 28 3.26 ± 0.03
300 37 4.8
400 44 4.45
100 1.13
* Errors given are standard deviation of 2-3 replicate
experiments
‡ (mass CNF/(mass CNF + mass of aniline))x100%
0
1
2
3
4
5
6
0 20 40 60 80 10Wt % CNF
Con
duct
ivity
(S/c
m)
0
Figure 2. A Plot of Composite Conductivity Versus Wt % Carbon
Nanofibers
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It is not unusual for conductivity values to vary for reaction
products prepared identically, or even for samples from the same
synthetic batch; the variation may be as high as 1 – 2 S/cm,
although the PAni/DBSA conductivity values appear to be
consistently between 0.25 and 0.5 S/cm, even under varying DBSA
concentration (0.03 – 1.0 M), and therefore varying pH. In
addition, several measurements of the CNFs consistently yield
conductivities of 1.1 ± 0.1 S/cm. This, in conjunction with the
consistence of the PAni/DBSA conductivities, would suggest that the
conductivity values for the high % nanofiber composites (30 – 80 %)
are statistically significant.
Polyaniline – Nanofiber (PAni/DBSA/CNF) Composites – Method
II
Two sets of experiments were performed using the Method II
procedure, in which the solid product was isolated from the
dissolved PAni/DBSA. In the first set, the amount of CNFs was
varied, and in the second set, the aniline was varied.
In the first set, the amount of aniline, and therefore aniline
concentration, was constant (0.055 M). Conductivity results for
these experiments are presented in Table 3. As the amount of CNF
increases, there appears to be little effect on the conductivity of
the isolated solid – varying the weight % CNF from 9 to 44, yielded
isolated solids having conductivity within a fairly narrow range
(5.4 ± 0.8 S/cm). In addition, the conductivity of the products
obtained from each reaction mixture filtrate falls within the
expected range of 0.25 to 0.5 S/cm for PAni/DBSA (0.3 ± 0.1 S/cm).
Based on the conductivity, it would appear that the solid isolated
in each experiment is of comparable composition. This is in
contrast to the composites obtained by precipitation of all
products (bulk solution, Table 2), in which the conductivity
increases with increasing nanofiber mass. Since the isolated solids
contain polyaniline, this method was performed in the absence of
any carbon nanostructures in order to rule out the possibility that
the polyaniline is simply an insoluble, high molecular weight, and
therefore more conductive fraction. Several pellets of PAni/DBSA
prepared by this method were pressed and the conductivity was found
to be 1.2 ± 0.6 S/cm.
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Table 3. Conductivity and Yield Data for PAni/DBSA/CNF
composites (Method II – variable CNF)
Conductivity* (S/cm) Yield (g) Mass CNF (mg)
Wt % CNF‡
solid filtrate residue solid filtrate residue
0 0 1.2 ± 0.6
50 8.9 5.66 0.45 0.065 0.065
100 16 6.3 ±0.8 0.27 ± 0.17 0.122 0.444
200 28 4.2 ± 0.6 0.14 ± 0.04 0.228 0.333
300 37 5.21 0.287 0.352 0.417
400 44 5.63 0.153 0.455 0.386
average 5.4 ± 0.8 0.3 ± 0.1
* Errors are standard deviation of values of replicate
experiments
‡ (mass CNF/(mass CNF + mass of aniline))x100%
The results for the increasing aniline concentration are
presented in Table 4. As the aniline concentration increases, the
yield increases dramatically, as expected, but the conductivity
remains fairly high and roughly constant. If the aniline is indeed
coating or wrapping around the nanofibers, there must be a point at
which the carbon surface is fully covered, and is therefore
saturated. At this point, the PAni/DBSA may either deposit or
polymerize onto itself (on the coating), or it may simply
precipitate without any interaction with the coated nanostructures.
Should the latter occur, it is reasonable to assume that the
overall conductivity of the isolated solid should decrease with
increasing proportion of PAni/DBSA relative to the PAni/DBSA –
coated nanofibers. The fact that the conductivity values remain
fairly high, and exhibit no trend as aniline content increases,
suggests that the PAni/DBSA is affected by the presence of the
nanotubes. Transmission electron microscopy (TEM) would be helpful
in determining if indeed the PAni/DBSA coating is simply becoming
thicker with increasing aniline content.
8 DRDC Atlantic TM 2003-206
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Table 4. Conductivity and Yield Data for PAni/DBSA/CNF
composites (Method II – variable aniline)
Conductivity* (S/cm) Yield (g) Mass CNF (mg)
Wt % CNF‡
solid filtrate residue solid filtrate residue
200 0.5 28 4.2 0.13 0.228
200 1.0 20 4.0 0.09 0.897
205 1.5 13 4.4 1.24
204 2.0 10 5.6 1.53
average 4.7 ± 0.7
* Errors are standard deviation of values of replicate
experiments
‡ (mass CNF/(mass CNF + mass of aniline))x100%
Polyaniline – Nanofiber (PAni/DBSA/CNF) Composites – Ex-Situ
As with the nanotubes, a composite was prepared by sonicating
then stirring a solution of PAni-DBSA with nanofibers (40 wt.%).
The isolated solid was dried and two pellets were pressed. The
average pellet conductivity was 3.5 ± 0.2 S/cm, which is higher
than the individual components, but somewhat lower than the in-situ
Method II products. It would appear that the nanofibers are
interacting with the polymer, which is consistent with the ex-situ
nanotube results, but not to the same extent as with the in-situ
approach.
For all experiments performed by Method II (isolate solid),
selected data are presented in Table 5. What is interesting about
the compiled data, is the consistence of the conductivity, 5.1 ±
0.8 S/cm, despite the wide range of carbon nanofiber content. It is
reasonable to anticipate that as the PAni/DBSA content increases,
that the conductivity would decrease, but this is not the case
here.
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Table 5. Conductivity and Content of Isolated Solid
Mass CNF (mg) Yield (g) Calculated CNF wt %a Conductivity
(S/cm)
50 0.065 77 5.66
100 0.122 82.0 6.3 ±0.8
200 0.228 87.7 4.2 ± 0.6
300 0.352 85.2 5.21
400 0.455 87.9 5.63
200 0.897 22.2 4.0
205 1.24 16.1 4.4
204 1.53 13.1 5.6
average 5.1 ± 0.8
a assuming no loss of carbon
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Conclusion These results, although preliminary, suggest the
formation of a highly conducting polyaniline – carbon nanostructure
composite, whose conductivity exceeds that of both components
individually. The nature of this electrical enhancement is not
clear, but there are several possibilities. The enhancement may be
due to a templating effect of the nanostructure, in which the
organization of the aniline prior to polymerization results in a
more favourable morphology. Alternatively, as has been suggested in
the literature, the presence of a synergistic electrical
interaction between the conducting polymer and the nanostructure
(and/or residual impurities in the nanostructure) could result in
conductivity enhancement. Lastly, the increased electrical
interaction between the two components could simply result from the
formation of a more efficient composite, perhaps due to greater
electrical contact between the carbon nanostructures via
polyaniline chains.
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9. McCarthy, B., Dalton, A.B., Coleman, J.N., Byrne, H.J.,
Bernier, P., Blau, W.J., Spectroscopic investigation of conjugated
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11. Zhang, J., Lee, J.-K., Wu, Y., Murray, R.W.,
Photoluminescence and Electronic Interaction of Anthracene
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DRDC Atlantic TM 2003-206 12
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List of symbols/abbreviations/acronyms/initialisms
APS ammonium persulfate
cm centimeter
CNF carbon nanofibers
DBSA dodecylbenzenesulfonic acid
DND Department of National Defence
g gram
kHz kiloHertz
M moles/liter
mg milligram
mm millimeter
mL milliliter
NT nanotube
PAni polyaniline
PmPV poly(m-phenylene-co-2,5-dioctoxy-p-phenylenevinylene
S Siemens
TEM transmission electron microscopy
TGA thermal gravimetric analysis
UV-vis ultraviolet-visible
W Watts
Wt weight
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AbstractRésuméExecutive summarySommaireTable of contentsList of
figuresList of tablesIntroductionExperimentalMethod I (bulk
solution)Method II (isolation of solid)
Results and DiscussionPolyaniline – Nanotube (PAni/DBSA/NT)
Composites – Method IPolyaniline – Nanotube (PAni/DBSA/NT)
Composites – Method IIPolyaniline – Nanotube (PAni/DBSA/NT)
Composites – Ex-SituPolyaniline – Nanofiber (PAni/DBSA/CNF)
Composites – Method Polyaniline – Nanofiber (PAni/DBSA/CNF)
Composites – Method Polyaniline – Nanofiber (PAni/DBSA/CNF)
Composites – Ex-Situ
ConclusionReferencesList ofDistribution list