Development and Applications of
Carbon Nanotube Textiles Korea-US Forum on Nanotechnology
September 30th 2014
Dr. Philip Bradford, Assistant Professor
Department of Textile Engineering Chemistry and Science
NC State University
How are CNTs Usually Processed?
…liquid based processing creates bundled CNTs whose fabrics loose functionality
CNT Powder Gojny et al., Compos. Sci. Tech.
2005
Length/diameter
ratio: 100-1000
How Do We Produce Our MWCNTs?
C2H2 2C + H2
750oC
Iron Catalyst
Length-to-diameter ratio of
~ 100,000
This is same as…
…a human hair that is 30 feet long!
… a pencil that is half a mile long!
Drawable CNT Sheets
Carbon Nanotube Sheet Take-up
CNT Sheet Nonwoven Fabrics If mandrel or CNT sheet is traversed during take-up, larger pieces of fabric can be
created
Applications We are Exploring
7
Aerosol Filtration
1.E-05
1.E-04
1.E-03
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
0.01 0.10 1.00
Pa
rtic
le P
en
etr
atio
n (%
)
Particle Size (µm)
Control
1 layer
2 layer
3 layer
7 layer
Yildiz O. and Bradford P. Carbon, 2013, 64:295-304.
High Strength Hybrid Nanofiber Fabrics
0
50
100
150
200
0 10
Str
ess (
MP
a)
Strain (%)
60%CNT30%CNT
Applications We are Exploring
Battery Electrodes
Fu, K., et al. Advanced
Materials, 2013,
25(36):5109-5114.
High Performance Composites
Wang X, et al, Mater. Res. Lett.,(1) 2012
5μm 2μm
a b
Stano K. et al., ACS Appl. Mater.
& Interfaces, 2013
Applications We are Exploring
Strain Sensing
0
5
10
15
20
0
50
100
150
200
250
300
350
0 0.5 1 1.5 2
Ele
ctri
cal R
esi
stance
Change (%
)
Str
ess
(M
Pa)
Strain (%)
Stress vs. Strain
Resistance Data - CNTs Perpendicular to Loading
Resistance Data - CNTs Parallel to Loading
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0 50 100 150 200 250
Resi
stance
Change (
%)
Str
ain
(%)
Time(s)
Strain (%)
Resistance Change (%)
High Performance Foams
0
10
20
30
40
50
60
70
Latex
(0.1
39)
PU (0
.027
)
Sili
cone
(0.2
72)
PU (0
.038
)
Rid
gid P
U (0
.027
)
Rid
gid P
E (0.0
32)
Al (
0.20
0)
Al (
0.21
6)
Al (
0.27
0)
CNT (0
.049
)
Al (
0.21
6)
Al (
0.20
9)
CNT (0
.079
)
CNT (0
.114
)
Foam Type (Density g/cm3)
Sp
ecif
ic C
om
pre
ssiv
e S
tren
gth
(M
Pa/g
cm
-3)
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 20 40 60 80 100
Co
mp
ressiv
e S
tress (M
Pa
)
Compressive Strain (%)
No anneal
30 min at 500oC in Air
Research Made Possible By:
My group members:
Kelly Stano
Ozkan Yildiz
James Stahl
Shagheyegh Faraji
Kun Fu
Spencer Barbour
Ang Li
Karim Aly
Jincheng Zhu
Funding agencies
AFOSR
ACS
NC Space Grant
Eastman Chemical
NASA
Thank you for
your attention!
Contact Information
919-515-1866
www.go.ncsu.edu/Bradford