SUPPLEMENTARY INFORMATION
Spectral and elemental analysis data of the PEIs obtained
PEI-1:
g
f
h
CH3 a' b'
b' a'
O
g
O
C
f
b
C
c
b
CH3 a
a
e
O
b
d
O
1
i
CH3 a
O
C
g
a
b
e
C
N
CH3 a' b'
a'
b'
f
O
g
f
O
C
N
c
d
C
n
O
H NMR (CDCl3, ppm, ): 1.69 (s, 6H, Hi), 1.75 (s, 6H, Hh), 6.96-7.25 (m, 16H, Ha, Hb, Ha’,
Hb’), 7.31-7.36 (m, 10H, Hc, Hf, Hg), 7.41-7.43 (d, 2H, He), 7.86-7.89 (d, 2H, Hd). FTIR (KBr,
cm –1): 2963 (C-H), 1777 (imide C=O stretch), 1724 (imide C=O stretch), 1375 (C-N stretch),
1240 (C-O-C), 744 (imide ring deformation). Anal. Calcd for (C58H42N2O8)n (894.96)n: C
77.83; H 4.73; N 3.13; Found: C 77.27; H 4.78; N 3.04.
PEI-2:
O
j
k
j
k
f
j
j
l
CH3 a
b
C
b
a
CH3
a
C
N
c
b
d
d
O
O
e
O
C
O
n
h
i
1
c
C
k
g
f
a
O
N
C
k
g
h
b
e
C
i
H NMR (CDCl3, ppm, ): 1.73 (s, 6H, Hl), 6.96-7.03 (m, 4H, Ha), 7.27-7.40 (m, 20H, Hb, Hc,
He, Hg, Hh, Hj, Hk), 7.42-7.44 (d, 2H, Hi), 7.75-7.78 (d, 2H, Hf), 7.84-7.87 (d, 2H, Hd). FTIR
(KBr, cm
–1
): 2967 (C-H), 1777 (imide C=O stretch), 1726 (imide C=O stretch), 1369 (C-N
stretch), 1239 (C-O-C), 751 (imide ring deformation). Anal. Calcd for (C56H36N2O6)n
(832.89)n: C 80.75; H 4.36; N 3.36; Found: C 79.40; H 4.61; N 3.72.
PEI-3:
O
f
C
b' a'
e'
1
g
h
C
O
c'
b
C
O
N
i
H3C
j
CH3 a
b'
a'
CH3 a
e
O
b
O
C
N
c
d'
d
C
n
O
H NMR (CDCl3, ppm, ): 1.75 (s, 6H, Hj), 2.24 (s, 3H, Hi), 7.00-7.06 (m, 4H, Ha), 7.30-7.37
(m, 6H, Hb,Hc), 7.37-7.41 (d, 2H, He), 7.41-7.43 (m, 1H, Hf), 7.44-7.51 (m, 2H, Hg, Hh), 7.847.90 (m, 2H, Hd). FTIR (KBr, cm
–1
): 2969 (C-H), 1777 (imide C=O stretch), 1723 (imide
C=O stretch), 1360 (C-N stretch), 1237 (C-O-C), 747 (imide ring deformation). Anal. Calcd
for (C38H26N2O6)n (606.62)n: C 75.23; H 4.32; N 4.62; Found: C 74.48; H 4.36; N 4.61.
PEI-4:
-1-
f
g
f
O
g
b
e
C
1
i
c
C
h
b
C
O
N
h
j
CH3 a
a
b
a
C
O
CH3
a
N
c
b
C
d
d
O
O
e
O
n
H NMR (CDCl3, ppm, ): 1.75 (s, 6H, Hj), 3.99 (s, 2H, Hi), 7.02-7.07 (m, 4H, Ha), 7.31-7.35
(m, 6H, Hb, Hc), 7.36-7.44 (d, 2H, Hg), 7.44-7.47 (d, 2H, He), 7.57-7.61 (d, 2H, Hh), 7.84-7.92
(m, 4H, Hf, Hd). FTIR (KBr, cm –1): 2966 (C-H), 1776 (imide C=O stretch), 1720 (imide C=O
stretch), 1364 (C-N stretch), 1238 (C-O-C), 742 (imide ring deformation). Anal. Calcd for
(C44H28N2O6)n (680.70)n: C 77.63; H 4.14; N 4.11; Found: C 76.44; H 4.22; N 4.07
PEI-5:
O
g
f
g
CF3 f
C
1
a
d
O
h
CH3 a
b
C
b
c
C
g
CF3 f
f
a
O
N
C
g
b
e
e
O
CH3 a
h
C
N
c
b
O
d
C
O
n
H NMR (CDCl3):  1.75 (s, 6H, Hh), 7.03-7.04 (d, 4H, Hb), 7.25-7.36 (m, 6H, Ha, Hc), 7.43
(s, 2H, He), 7.51-7.55 (m, 8H, Hf, Hg), 7.89-7.90 (d, 2H, Hd). FTIR (KBr, cm –1):  2970 (CH), 1780 (C=O), 1730 (C=O), 1370 (C-N), 1241 (C-O-C), 1209, 1175 (C-F), 746 (C-N)
Anal. Calcd for (C46H28N2O6F6)n (818.71)n: C, 67.48; H, 3.44; N, 3.42; Found: C, 65.47; H,
3.42; N, 3.47
PEI-6:
d
c
b
a
h
CH3 a
a
CH3 a
C
O
d
c
b
b
c
O
b
O
d
C
c
d
CF3
e
C
N
O
C
N
f
C
O
1
e
g
f CF3
g
C
n
O
H NMR (CDCl3, ppm, ): 1.70 (s, 6H, Hh), 6.96-7.00 (d, 4H, Ha), 7.09-7.12 (d, 4 H, Hb),
7.22-7.25 (d, 4H, Hd), 7.33-7.36 (d, 4H, Hc), 7.85-7.88 (d, 2H, Hf), 7.92 (s, 2H, He), 8.01-8.04
(d, 2H, Hg). FTIR (KBr, cm
–1
): 2970 (C-H), 1784 (imide C=O stretch), 1725 (imide C=O
stretch), 1379 (C-N stretch), 1242 (C-O-C), 1209, 1192 (C-F), 742 (imide ring deformation).
Anal. Calcd for (C46H28N2O6F6)n (818.71)n: C 67.48; H 3.44; N 3.42; Found: C 65.94; H 3.58;
N 3.63.
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Figure 1S. Aromatic regions of the 1H NMR spectra of PEI-1 (a), PEI-3 (b), PEI-4 (c), PEI-5
(d), and PEI-6 (e)
a)
b)
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c)
d)
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e) PEI-6
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Discussion of the 1H-NMR spectra of PEIs
In the PEI-1 spectrum, the sensitivity of the aromatic protons of the isopropylidene diphenyl
unit to the differences in their vicinity, despite rather similar chemical environment, is clearly
seen that results in four distinct AB doublets observed for two such group in the repeating unit
of PEI-1 (protons a, a’, b, b’). Aromatic portion of PEI-3 reflects again sensitivity of the
isopropylidene diphenyl protons to slight differences in their vicinity, this time due to
asymmetry of the repeating unit. Introduction of the asymmetric methylophenyl structure in
the main chain results in discrimination of two different parts in the isopropylidene diphenyl
structure, that is, left and right with respect to the central linking carbon. In consequence,
analogous protons (denoted by prims) resonate at slightly different frequencies, yielding
separate signals. Therefore, for the signals well separated from the superimposed ones, two
distinct doublets are observed, for example for d and d’ protons, as well as for a and a’ ones,
however, the latter exhibit apparent triplet due to coincident superposition of the internal
doublet lines. 1H NMR spectrum of PEI-4 is relatively simple. Chemical shifts, relative
intensities obtained from integration of the separated regions and spin couplings confirm well
the chemical structure of the polymer repeating unit. 1H NMR spectrum of PEI-6 reflects well
the symmetry of the repeating unit exhibiting four clear AB doublets for the isopropylidene
diphenyl and phenyl protons. Relatively high chemical shifts of the f, e and g protons at 7.86,
7.92 and 8.02 ppm, respectively, are due to the deshielding effects of the neighboring fluorine
atoms. The chemical structure of the repeating unit of PEI-5 is also well confirmed by
chemicals shifts, relative intensities as well as spin couplings of the respective signals.
Discussion of the elemental analysis data
The chemical composition of the obtained polymers was also confirmed by the elemental
analysis data. Considering the content of nitrogen and hydrogen in the proposed structures,
the results of the elemental analyses show a good agreement with the calculated values.
However, a deficiency in carbon content of 0.56-1.93% was observed. The observed deviation
of the experimental values from the calculated ones can be explained by one or all of the
following facts: (i) influence of the end group of the polymeric chain, (ii) dispersity of molar
masses due to polycondensation reaction, and (iii) a result of the difficulties in burning of
these polymers.[1S]
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Thermal behavior of PEIs
Figure 2S. TGA thermograms of PEI-2
Discussion of Tg obtained from DMA measurements
In DMA analysis, Tg can be defined in three ways:[28] (i) the temperature at which dynamic
storage modulus (E’) has fallen to a certain value; (ii) the temperature at which tan  has its
maximum value; and (iii) the temperature at which loss modulus (E”) has its maximum value.
The temperature dependence of the dynamic storage modulus (E’), loss modulus (E”) and tan
 is shown in Figure 3S for PEI-6 as the exemplary polymer.
Figure 3S. Viscoelastic spectrum of the PEI-6 film
The glass transition temperature, determined based on the results of DMA measurements in
the three varied ways mentioned above, ranges from 198 C to 300 C. These values are
comparable with the Tg ones obtained from the DSC runs within the difference range between
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5-25 C. It was found that Tg, determined as the temperature, at which tan  attains its
maximum value, was higher than or equal to Tg from the DSC measurements (see Tables 4
and 5 in the main text). If Tg was defined as E’ inflection point (I in Table 5), its values, in
most cases, were lower (by about 5-18 C) than those obtained from the DSC thermograms.
The differences between the DSC and DMA data can be attributed to the different response of
PEIs to the evaluation system.[2S] However, considering the polymer chemical structure, the
similar tendency in Tg values determined from both DSC and DMA measurements was
observed.
Mechanical properties of PEIs
As can be seen from Table 6 in the main text, tensile strengths of the synthesized PEIs were
similar and only slightly lower than that of Ultem, except for PEI-4 derived from IPDA and
4,4’-(9-fluorenylidene)dianiline. It is suspected that a low molecular weight is responsible for
the lower tensile strength value determined for this polymer. However, the above explanation
cannot reach a definitive conclusion since any GPC characterization was carried out for PEI-4
because of its insolubility in DMF. On the other hand, PEI-4 showed the high value of tensile
modulus, similar to that of Ultem. Considering elongation at breakage, PEI-6 prepared from
4,4’-(4,4’-isopropylidene-diphenyl-1,1‘-diyldioxy)dianiline and 6FDA was found to exhibit
the highest value comparing to the other PEIs tested. This value is a few times higher than
those obtained for PEI-2, PEI-3, and PEI-4, and not much lower than that measured for
Ultem. Generally, the tensile stress parameters of PEIs indicate that they are strong and tough
polymeric materials.
Additional references
1S. Yang, C.-J., Jenekhe, S. A. Conjugated Aromatic Polyimines. 2. Synthesis, Structure, and
Properties of New Aromatic Polyazomethines. Macromolecules 28, 1180-1196 (1995)
2S. Rieger, J. The glass transition temperature Tg of polymers-Comparison of the values from
differential thermal analysis (DTA, DSC) and dynamic mechanical measurements (torsion
pendulum). Polym. Test. 20, 199-204 (2001)
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