Supporting Information
Orientation and Mechanical Properties of Laser-Induced Photothermally Drawn Fibers
Composed of Multi-walled Carbon Nanotubes and Poly(ethylene terephthalate)
Jin Wuk Hur, Hye Jin Yoo, Jae Whan Cho,* Kyoung Hou Kim*
Figure S1 Dependence of the applied drawing stress on the draw ratio in the photothermal
drawing of the PET/MWCNT fibers performed at a laser power density of 3.75 W/cm-1.
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Figure S2 The stress-strain curves of photothermally drawn PET/MWCNT fibers at (a) 0.5 and
(b) 1.0 wt% of MWCNT content, and (c) the toughness of photothermally drawn PET/MWCNT
fibers.
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Figure S3 (a) The breaking stress, (b) modulus, and (c) elongation-at-break of hot drawn PET,
PET/MWCNT (0.5 wt%) and PET/MWCNT (1.0 wt%) at different draw ratios.
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FIGURE S4 (a) WAXD images and X-ray diffractograms along (b) the equatorial and (c)
meridional directions of undrawn (i) pure PET, (ii) PET/MWCNT (0.5 wt%), and (iii)
PET/MWCNT (1.0 wt%) fibers.
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FIGURE S5 Equatorial intensity profiles with peak fitting and separation for the photothermally
drawn PET/MWCNT fibers at a draw ratio of (a) 4.0 and (b) 5.0.
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FIGURE S6 Crystallinity of the photothermally drawn PET/MWCNT (0.5 wt%) fibers with
different draw ratios, which was obtained from DSC melting curves using a perfect heat of
fusion of 140 J/g for PET.1
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FIGURE S7 The polarized Raman spectra of photothermally drawn PET/MWCNT (0.5 wt%)
fibers at a draw ratio of (a) 2.0, (b) 3.0, (c) 4.0 and (d) 4.5.
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Evaluation of Orientation Factor from WAXD Results
The intensity profiles along the diffraction angle were taken from the obtained images. The size
of crystallite dimension was estimated from the diffraction peaks of the profiles. The position θ0
and full width at half maximum σ of the diffractions were determined by fitting a Gaussian
function (Eq. 1). The beam divergence effect on σ was corrected by the width of the intensity
profiles of StPb. The crystallite dimension D was calculated by Scherer's equation (Eq. 2), where
the constant k in Eq. 2 was 0.918. The crystal orientation factor f was estimated from the
azimuthal intensity profiles for the (010), (-110) and (100) planes. For this purpose, azimuthal
intensity profiles were fitted by a Pearson VII equation (Eq. 3), assuming equal width for the
three diffractions. The crystal orientation f was estimated using Eq. 4 by integrating the fitted
profiles.
2
   0  

I    I 0 exp 4 ln 2  
 
   

k
D
 sin  0
I ( )  
f 
(1)
(2)
I0

   0  
1  4 
 2
   

2
3 cos 2   1
2
1
2.5
 
 1 
 
 2
,
cos 
2


0
(3)
2.5
I (  ) cos 2  sin d
 2

0
I (  ) sin d
(4)
REFERENCES
1 A. Metha, U. Gaur, B. Wunderich, J. Polym. Sci., Part B: Polym. Phys. 1978, 16, 289-296.
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