Synthesis of poly(isopropenylphenoxy propylene carbonate) and its facile side-chain functionalization into hydroxy-polyurethanes

Article abstract of DOI:10.1002/pola.27914

4-Isopropenyl phenol (4-IPP) is a versatile dual functional intermediate that can be prepared readily from bisphenol-A (BPA). Through etherification with epichlorohydrin to the phenolic group of 4-IPP, it can be converted into 4-isopropenyl phenyl glycidyl ether (IPGE). On further reaction with carbon dioxide in the presence of tetra-n-butyl ammonium bromide (TBAB) as the catalyst, IPGE was transformed into 4-isopropenylphenoxy propylene carbonate (IPPC) in 90% yield. Cationic polymerization of IPPC with strong acid such as trifluoromethanesulfonic acid or boron trifluoride diethyl etherate as the catalyst at -40 C gave a linear poly(isopropenylphenoxy propylene carbonate), poly(IPPC), with multicyclic carbonate groups substituted uniformly at the side-chains of the polymer. The cyclic carbonate groups of poly(IPPC) were further reacted with different aliphatic amines and diamines resulting in formation of polymers with hydroxy-polyurethane on side-chains. Syntheses, characterizations of poly(IPPC) and its conversion into hydroxy-polyurethane crosslinked polymers were presented.

Full text of DOI:10.1002/pola.27914

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Synthesis of Poly(isopropenylphenoxy propylene carbonate)
and Its Facile Side-Chain Functionalization
into Hydroxy-Polyurethanes
Chun Chieh Huang, Ching Hsuan Lin, Shenghong A. Dai
Department of Chemical Engineering, National Chung Hsing University, Taichung 40227, Taiwan
Correspondence to: S.A. Dai (E-mail: shdai@nchu.edu.tw)
Received 24 June 2015; accepted 28 August 2015; published online 7 October 2015
DOI: 10.1002/pola.27914
ABSTRACT: 4-Isopropenyl phenol (4-IPP) is a versatile dual func-
tional intermediate that can be prepared readily from
bisphenol-A (BPA). Through etherification with epichlorohydrin
to the phenolic group of 4-IPP, it can be converted into 4-
isopropenyl phenyl glycidyl ether (IPGE). On further reaction
with carbon dioxide in the presence of tetra-n-butyl ammo-
nium bromide (TBAB) as the catalyst, IPGE was transformed
into 4-isopropenylphenoxy propylene carbonate (IPPC) in 90%
yield. Cationic polymerization of IPPC with strong acid such as
trifluoromethanesulfonic acid or boron trifluoride diethyl ether-
ate as the catalyst at 240 8C gave a linear poly(isopropenylphe-
noxy propylene carbonate), poly(IPPC), with multicyclic
carbonate groups substituted uniformly at the side-chains of
the polymer. The cyclic carbonate groups of poly(IPPC) were
further reacted with different aliphatic amines and diamines
resulting in formation of polymers with hydroxy-polyurethane
on side-chains. Syntheses, characterizations of poly(IPPC) and
its conversion into hydroxy-polyurethane crosslinked polymers
were presented. C
V
2015 Wiley Periodicals, Inc. J. Polym. Sci.,
Part A: Polym. Chem. 2016, 54, 802–808
KEYWORDS: cationic polymerization; cyclic carbonate; non-iso-
cyanate route; polyurethanes; side-chained polyurethane; syn-
thesis; thermosetting polymers
8
INTRODUCTION The non-isocyanate route (NIR) for produc-
tion of polyurethanes (PUs) using ring-opening reaction of
polycyclic carbonates with diamines has been touted as one
of the most potentially useful green chemistry routes to PUs
enhancing physical properties. In 1993, G. Chen et al. pre-
pared PU-hydrogel beads for immobilization of enzymes by
reacting poly(vinylene carbonate) with difunctional Jeff-
amines. More recently, several other groups carried out
1
–6
13
in recent years.
This ring-opening reaction involving a
homo and copolymerized of acrylic and styrenic interme-
1
4
cyclic carbonate with aliphatic amines will result in b-
diates possessing cyclic carbonates. They did result in
obtaining highly functionalized polycarbonates for curing by
diamines. Through these NIR approaches, highly crossliked
PU-products did show improved solvent resistance and ther-
mal stability.
hydroxyls as side-groups on urethane main chains, and thus
7
,8
this route has been applied to synthesize hydrophilic PUs.
However, this NIR process generally produces PUs with low
molecular weights and low T which have hampered its use-
g
fulness in applications. Recently, several research groups
have tried further modification of side-chained hydroxyl
1
5
Previously, Ito et al. prepared 4-isopropenylphenyl ether
derivatives starting from BPA and they polymerized the iso-
propenyl groups into a linear polymer by cationic polymer-
9
–11
group after ring-opening of cyclic carbonate,
while others
have used tri-functional-cyclic carbonate reacting with dia-
1
6
1
2
ization. Subsequently, Higashimura and coworkers
mines to overcome the performance deficiencies. However,
the quality of films or properties of polymers still have not
been satisfactory, and hence this NIR strategy still needs for
further improvements.
succeeded in making poly(isopropenyl phenyl glycidyl ether),
poly(IPGE), under strong acids such as hydroiodic acid (HI)
as the initiator of choice at low-temperature conditions.
However, no synthesis of poly(IPGE) through its glycidyl
groups have been reported so far. In this study, we followed
the same synthetic routes from BPA to make IPGE but we
have further extended the synthesis to 4-isopropenylphenoxy
propylene carbonate (IPPC) and poly(IPPC) (Scheme 1).
Synthesis of highly functionalized cyclic carbonate prepoly-
mers through polymerization of vinyl-monomers bearing
cyclic carbonates have been reported as yet another NIR-
strategy of making crosslinked polyurethanes as means of
Additional Supporting Information may be found in the online version of this article.
2015 Wiley Periodicals, Inc.
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C
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SCHEME 1 Synthesis and polymerization of IPPC and poly(IPPC) from bisphenol A.
Through the highly functionalized crystalline polymer prede-
cessor, poly(IPPC), as our key PU hard-component raw mate-
rial in this report, PU films were prepared readily with
interesting characteristics. (Scheme 2).
chased from Aldrich. Jeffamine M600 (polyether amine,
M 5 600 g/mol), Jeffamine D230 (polyether diamines,
w
M 5 230 g/mol), D2000 (polyether diamines, M 5 2000 g/
w
w
mol), and 1,3-Bis(3-aminopropyl)21,1,3,3-tetramethyldisilox-
ane (PAM-E, M 5 260 g/mol) were supplied from Great
w
EXPERIMENTAL
Eastern Resins Industrial of Taichung, Taiwan. Acetonitrile
was purchased from Aencore and purified by distillation
under reduced pressure over calcium hydride (Acros) and
stored over molecular sieves (water-content is lower than
Materials. Bisphenol-A, (1/2)epichlorohydrin, methanesul-
fonic acid, trifluoromethanesulfonic acid, boron trifluoride
diethyl etherate and tetra-n-butylammonium bromide
1
00 ppm before each polymerization reaction). All other sol-
(
(
TBAB) were purchased from Alfa Aesar. Isophorondiamine
IPDA), and 1,6-hexanediamine (HDA) were purchased from
vents in the experiments were commercial products used
without further purification.
Acros. 4,4’-Methylene biscyclohexylamine (H MDA) was pur-
1
2
SCHEME 2 Ring-opening reaction of poly(IPPC) with high ratio diamines curing. [Color figure can be viewed in the online issue,
which is available at wileyonlinelibrary.com.]
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TABLE 1 The Results of Polymerization of IPPC
4
a
4 a
ꢁ
b
ꢁ
b
Entry
Initiator Type
[M
0
] mmol/L
[I] mmol/L
M
n
(310 )
M
w
(310 )
PDI
T
m
( C)
T
g
( C)
Yield
1
2
3
4
5
6
7
8
9
CF
CF
CF
CF
3
3
3
3
SO
SO
SO
SO
3
3
3
3
H
H
H
H
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.012
0.016
0.022
0.025
0.024
0.035
0.050
0.076
0.015
0.017
0.023
0.029
1.15
0.84
0.47
0.65
0.33
0.34
0.44
0.33
1.59
1.22
1.52
0.83
2.50
1.88
1.40
0.95
0.93
0.83
1.03
0.83
3.55
2.97
2.34
1.79
2.2
2.3
3.0
1.5
2.8
2.5
2.3
2.6
2.2
2.4
1.5
2.2
184
194
193
190
180
185
193
183
n/a
170
156
152
152
132
n/a
135
140
n/a
n/a
n/a
139
83%
90%
88%
80%
44%
26%
31%
27%
83%
88%
85%
52%
CH
CH
CH
CH
3
SO
3
SO
3
SO
3
SO
3
H
H
H
H
3
3
3
BF
BF
BF
BF
3
OEt
OEt
OEt
OEt
2
1
1
1
0
1
2
3
3
3
2
2
2
n/a
190
189
a
b
Measured by GPC under NMP solvent system.
Measured by DSC at a heat rate of 10 8C/min.
Preparation of 4-Isopropenyl Phenol from Bisphenol A
The preparation of 4-isopropenyl phenol was according to
completely. The catalyst was then removed by extraction and
the product was isolated by crystallization using ethanol.
The white solid product (5.27 g; 90%) was isolated. Mp5
107–108 8C. FTIR (KBr): v 5 1797 (C@O of carbonate), 1621,
1
7
the Schnell method
dure. BPA (0.5 mol) and traced NaOH(s) (0.2 g) was added
to a reaction flask, and then the pyrolysis was carried out at
and our previous modified proce-
1
8
2
1 1
1606 (C@C of isopropenyl) cm . H NMR (400 MHz, DMSO-
d , d): 2.07 (s, 3H, CH ), 4.19–4.40 (m, 2H, CH ), 4.65 (d, 2H,
230–250 8C under 15 mmHg. The resulting mixtures of 4-
6
3
2
a
isopropenyl phenol and phenol were collected in a receiving
flask. Then, traced NaOH(s) (0.2 g) was again added to the
mixed products, and the mixture immediately underwent a
fractionation at 150 8C under 20 mmHg to remove phenol.
This was followed by heating the remaining IPP and IPP
oligomers at temperatures of 230–250 8C under the 15
mmHg to produce IPP. Yields of 4-IPP were between 85–
OCH ), 4.98(s, 1H, C@CH ), 5.15 (m, 1H, CH), 5.32 (s, 1H,
2
b
C@CH ), 6.91–6.94 (m, 2H, ArAH), 7.43–7.45 (m, 2H, ArAH).
1
3
C NMR (400 MHz, DMSO-d ): d 21.49, 65.95, 67.50, 74.76,
6
110.91, 114.35, 126.49, 133.49, 141.70, 154.76, 157.47.
1
HRMS (EI, m/z): [M1H] Calcd for C H O , 234.0892;
1
3 14 4
Found, 234.0895.
9
2% stored in anisole as the IPP stabilized solution to pre-
Cationic Polymerization of IPPC
vent its oligomerization.
The 2.00 g (8.5 mmol) of IPPC was dissolved in acetonitrile
(20 mL), and the solution was added into a 50 mL round-
bottom flask with magnetic stirrer under a nitrogen purge.
The resulting mixtures were then slowly cooled by acetone/
Preparation of 4-Isopropenylphenoxy Propylene
Carbonate (IPPC)
The solution of 4-IPP (0.12 mol 4-IPP in 30 mL anisole), epi-
chlorohydrin (0.24 mol) and triethylene amine (0.012 mol)
liquid nitrogen bath and kept at 240 8C. CF SO H was
3 3
1
9
was added into a 250 mL three-neck flask. The reaction
solution was heated and stirred vigorously at 90 8C under
dry nitrogen atmosphere. After 1 h, the reaction was cooled
to 40 8C, and then 5N NaOH(aq) (25.2 mL) was slowly added
to the solution. The mixture was further stirred for 2 h at 40
injected into the reaction solution by a syringe, and the solu-
tion was stirred for 2 h. Finally, the solution was poured into
an ethanol containing dilute ammonium hydroxide. The pre-
cipitated polymer product was collected by filtration (see
Table 1 for the weights of acid added and resulting yield).
8C. The organic layers were washed with 2N NaOH(aq) and
DI-water until the solution became neutral. The excess epi-
chlorohydrin and anisole were removed by fractionation
under reduced pressure. Finally, 17.0 g (75%) of the IPP-
glycidyl ether (IPGE) was obtained by recrystallization using
Curing Reaction of Poly(IPPC) with Amines via
Ring-Opening of Cyclic Carbonate
Poly(IPPC) (0.5 g; M 5 23,000 g/mol) and diamines [ꢀ0.8
w
1
9
equivalnet relative to poly(IPPC)] were dissolved in 4.5 g of
N-methyl-2-pyrrolidone (NMP). The solution of the reaction
mixture was heated at 100–130 8C for 12 h. Then, the result-
ing solution was poured into a circle Teflon mold of 4.0 cm
(Diameter) in size, which was placed into an oven at 60 8C
for about 24 hours to remove NMP. The melt-product was
shaped into PU film to get the final films for testing.
ethanol. Mp5 25–26 8C (lit. 44–45 8C).
Then, IPGE (0.025 mol), toluene (60 mL) and TBAB
(
0.01 mol) were added into a three-neck flask, and the mix-
ture was then purged with carbon dioxide gas at 80 8C for
h while being monitored by FTIR. The reaction was termi-
8
2
1
nated when the epoxy absorption at 910 cm disappeared
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Characterization
Fourier transform infrared (FTIR) were recorded over the
2
1
range from 4000–450 cm using a Perkin-Elmer Spectrum
One FTIR spectrometer. NMR spectra were recorded on a
Varian Inova 400 NMR in DMSO-d6 and the chemical shifts
were calibrated by setting the chemical shift of DMSO-d at
6
€
2
5
.49 ppm. Melting points were measured using a BUCHI B-
40 melting-point apparatus operated at a heating rate at
raising rate of 3 8C/min. Electron ionization (EI) mass spec-
tra were recorded using a Finnigan/Thermo Quest MAT
95XL apparatus. Differential scanning calorimetry (DSC)
scans were obtained using a Seiko SII model SSC/6200
under a nitrogen atmosphere at a heating rate of 10 8C/min.
Thermal gravimetric analysis (TGA) was performed with a
Seiko SII model SSC/5200 at a heating rate of 10 8C/min
under nitrogen atmosphere. Gel permeation chromatography
FIGURE 1 FTIR monitoring conversion of epoxy into cyclic car-
TM
(
GPC) was conducted on a Viscotek
MBLMW-3078 utiliz-
2
bonate functions from IPGE by CO -carbonylation. [Color figure
ing MBHMW-3078 column and utilizing N-methyl-2-
pyrrolidone (NMP) as mobile phase at rate of 1.0 mL/min
under 40 8C. The molecular weight of polymer products was
calibrated by using polystyrene as the standard. Mechanical
properties of the product were performed on a Universal
can be viewed in the online issue, which is available at
wileyonlinelibrary.com.]
found to be unsatisfactory in our case because of their poor
solubility for IPPC under the low-temperature condition. It
was found that the polymerization of IPPC is best done in ace-
tonitrile at 240 8C. Furthermore, highly strong acid initiators
seemed essential in the cationic polymerization of IPPC. Based
on effectiveness and selectivity of the polymerization, tri-
fluoromethanesulfonic acid has been found to be the best acid
initiator among all initiators tried so far. Trifluoromethanesul-
2
Shimatsu HT-8504 by a 20.0 3 10.0 mm sample film with a
testing rate set at 100 mm/min.
RESULTS AND DISCUSSION
Synthesis and Characterization of IPPC
4-Isopropenylphenoxy propylene carbonate (IPPC) was pre-
fonic acid gave 83–90% isolated yields of homopolymer at
pared from 4-isopropenyl phenyl glycidyl ether (IPGE)
1
2
40 8C in 1.5 h. As H-NMR spectrum of poly(IPPC) shown in
according to the CO -carbonylation method reported by
2
1
9
Supporting Information Figure S2-a, all original vinylic protons
of poly(IPPC) disappeared. All proton chemical shifts of the
new product in the NMR spectrum could be assigned as indi-
cated in Supporting Information Figure S2. The molecular
weight of final poly(IPPC) were found to be ranging from
Heinrich et al. In the first step of our synthetic sequence,
-IPP and epichlorohydrin were mixed in anisole in the pres-
4
ence of triethylamine as the catalyst, and the solution was
stirred at 90 8C for converting phenolic group into the epox-
ide intermediate. After 1h, the reaction was then cooled to
8000 to 35,000 g/mol (with DP of 1.5–3.0), which appear to
40 8C followed by treatment with 5N NaOH(aq) to effect the
be determined by the amount of trifluoromethanesulfonic acid
added. The plots of the polymer’s Mw versus catalyst concen-
tration were exhibited in Figure 2, where a straight line could
be drawn only in the runs of trifluoromethanesulfonic acid. In
boron trifluoride diethyl etherate and methanesulfonic acid
initiated polymerizations both showed comparatively lower
efficiency of initiators and thus giving higher molecular
weights of poly(IPPC) but their polymer products seem to be
less structurally regioselective as those from trifluoromethan-
sulfonic acid as indicated in molecular weight data (Support-
ing Information Fig. S3) with thermal analysis data shown in
Table 1. The most optimal concentration of trifluoromethane-
sulfonic acid was found at 0.012 mmol/L (Run 1, Table 1)
since it gave high molecular weights of the product in 1.5 h
ring-closure in formation of glycidyl ether intermediate. After
the isolation and recrystallization of the products in metha-
nol, IPGE was isolated in 75% yield (Mp 5 25–26 8C). This
1
9
melting point was lower than previous literature data (lit.
4–45 8C) and the dis-agreement may be due to (1/2) epi-
4
chlorohydrin was used as the epoxidation agent in our run
as the starting material, which was different from the
1
9
Heinrich’s method . After that, IPGE was treated with CO
2
2
0,21
in toluene solution using TBAB
as catalyst, and the car-
bonylation further transformed IPGE into the corresponding
carbonate at 80 8C under the monitoring of FTIR (Fig. 1).
The isolated yield of IPPC was 90% (Mp 5 107–108 8C) and
1
its chemical structure was firmly established by its H-NMR
(
Supporting Information Fig. S1) and HRMS analyses.
and highest glass transition temperature (T
170 8C (M 5 25,000) among all runs. In Run 5 to 8 initiated
by methanesulfonic aicd, the T has been recorded as low as
g
) of poly(IPPC) at
Synthesis, Characterization and End-Group
Stabilization of Poly(IPPC)
w
g
In our cationic polymerization experiments of IPPC, both
methylene chloride and toluene used in previous Higa-
shimura’s synthesis of poly(IPGE) as the solvents were
130 8C which seems correlated to its small M (8000–10,000).
w
In TGA analysis, the 5% weight loss (T ) of most poly(IPPC)s
d
1
6
were found to be at around 260 8C.
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FIGURE 2 Correlation between molecular weights of poly
IPPC)s with catalyst concentrations [I]. [Color figure can be
(
FIGURE 3 FTIR of ring-opening reaction of cyclic carbonate
from poly(IPPC) by Jeffamine M600. [Color figure can be
viewed in the online issue, which is available at wileyonlineli-
brary.com.]
viewed in the online issue, which is available at wileyonlineli-
brary.com.]
1
Under closer inspection of H-NMR spectra of all prepared
poly(IPPC), the polymers showed several tiny NMR peaks of
olefin protons located at 4.99, 5.33, and 4.88 ppm in the
NMR, which were assigned to the terminal exo- and endo-
In a similar thermoset PU synthesis, poly(IPPC) dissolved in
NMP, was added to polypropylene ether diamine of 2000
molecular weight (Jeffamine D-2000) with the relative ratio
of 1/0.8 equivalent weight at 130 8C. After the resulting
solution was vigorous stirred for 12 h, the solution was
poured into a Teflon mold for the solvent removal under
reduced pressure. By doing so, a highly crosslinked PU with
new urethane absorption at 1710 cm in FTIR spectra was
obtained. The product, NIPU-A (Table 2), exhibited as a light
yellow opaque film with only slight cyclic carbonate and
urea-absorption detected in its FTIR spectrum. (Fig. 5).
Another interesting phenomenon was observed in the run
where the relative equivalent ratios of Jeffamine D2000 to
poly(IPPC) was decreased to 1/0.6 or lower, respectively. In
all those runs, insoluble crosslinked polymeric products
formed rapidly. For example, NIPU-B (Table 2) was obtained
in the run with 50% equivalent ratio of Jeffamine D2000
1
6
protons, respectively (Supporting Information Fig. S2-b). In
order to stabilize the polymers from further chemical com-
1
8
plications such as acid initiated dispropornations, cumene
hydroperoxide (80% solution) treatment of poly(IPPC) in
the presence of CuCl2 was carried out to effectively oxidize
these terminal groups leading to new carbonyl functions as
21
2
2
the terminal group. Without this oxidation treatment, poly
IPPC) has been observed to undergo acid-catalyzed equili-
(
brations resulting in lower molecular weight distributions.
Amination of Poly(IPPC) for Its Side-Chain
Functionalization into Hydroxy-Polyurethanes
In an attempt to introduce b-hydroxy-polyurethane side-
chains into poly(IPPC) via amination of its cyclic carbonate
groups, we added aliphatic mono- or diamines as the
reagents in various equivalent ratios relative to cyclic car-
bonate of poly(IPPC) to promote ring-opening reactions.
These functionalizations were done primarily on the poly(-
IPPC) with M 5 23,000 g/mol, the trifluoromethanesulfonic
w
acid initiated polymers (entry 2, Table 1).
As a typical run, 0.5g of poly(IPPC) dissolved in 3.5 g NMP
was treated with 1.03 g of Jeffamine M600, a mono-
polypropylene etheramine of 600 g/mol molecular-weight.
The relative molar equivalent of poly(IPPC) to Jeffamine
M600 is calculated to be approximately 1/0.8 and the reac-
tion was done at 130 8C with vigorously stirred for 12 h. As
shown in Figure 3, the IR spectra indicated that the intensity
21
of the initial carbonate carbonyl absorption at 1799 cm
reduced substantially after 6 h, while the new carbonyl
groups of urethane intensified with the new absorption at
2
1
1
710 cm . In Figure 4, the GPC spectra of the resulting
FIGURE 4 GPC analysis of poly(IPPC) and poly(IPPC)-M600.
[Color figure can be viewed in the online issue, which is avail-
able at wileyonlinelibrary.com.]
adduct concurrently showed a distinct molecular-weight
increase.
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TABLE 2 The Results and Analyses of NIPU Synthesized from Poly(IPPC) and Different Diamines
Eq. ratio of
Diamine
Wt % of
Diamine
Tensile Strength
(MPa)
Elongation
(%)
a
a
b
Sample
Diamines
T
m
(8C)
T
g
(8C)
Td5% (8C)
NIPU-A
NIPU-B
NIPU-C
NIPU-D
NIPU-E
NIPU-F
NIPU-G
IONIPU
D2000
80%
77%
n/a
207
181
n/a
n/a
194
n/a
208
n/a
n/a
n/a
85
297
295
234
246
240
260
253
190
0.26
0.36
n/a
n/a
n/a
n/a
1.3
71.2
89.2
n/a
D2000
50%
68%
HDA
80%
17%
H12-MDA
IPDA
80%
26%
n/a
80%
23%
98
n/a
D230
80%
28%
83
n/a
D2000/D230
PAM-E
80%/20%
80%
76%/2%
31%
143
n/a
9.6
2.4
26.2
a
b
Measured by DSC at a heat rate of 10 8C/min.
Temperature corresponding to 5% weight loss by themogravimetry at
a heat rate of 10 8C/min in the atmosphere of nitrogen.
different molar ratios are intriguing (Fig. 6). In parts, the
reason of insolubility may be because of less soluble cross-
linked poly(IPPC) that still possessed higher rigid-cyclic car-
bonate groups in the products. On the other hand, another
probable reason may be due to the result of forming a fence-
like polymer product between two homo-poly(IPPC) chains
and diamines as shown in Scheme 2 particularly when high
concentrations of diamines were added all at once to poly
(IPPC). In SEM and AFM analysis of D2000 cured sample of
NIPU-A, the results appear to support the postulated mor-
phologies comprising of numerous fence-like structures.
(
Supporting Information Fig. S4-S5).
Since NIPU-A cured by Jeffamine D2000 yielded a very soft
film which is lack of mechanical properties, we have carried
out similar syntheses of NIPU by addition of several short-
chained diamines such as HAD, H12MDA, IPDA, and D-230
FIGURE 5 FTIR of curing reaction of poly(IPPC) via ring-
opening of cyclic carbonate by Jeffamine D2000. [Color figure
can be viewed in the online issue, which is available at
wileyonlinelibrary.com.]
(NIPU-C, -D, -E, and -F, respectively) under 100 8C for 6 h
for comparison as shown in Table 2. All these NIPUs turned
into highly rigid PU films. However, when 1,3-Bis(3-amino-
propyl)-1,1,3,3-tetramethyldisiloxane, PAM-E, were applied in
equivalent ratio of 0.8 to poly(IPPC) as the curing agent, and
we obtained an elastic hybrid PU’s film (IONIPU). Clearly,
siloxane-based diamines could impart necessary flexibility to
additon, and this product seemed much harder than NIPU-A,
but its tensile stress is much poorer. The different rates of
crosslinked product formations from same diamine but in
FIGURE 6 Fluidity of cured poly(IPPC) with D2000 in ratio of (a) 1/0.8 (b) 1/0.3. [Color figure can be viewed in the online issue,
which is available at wileyonlinelibrary.com.]
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ACKNOWLEDGEMENTS
The financial support of this research is provided in part by
Ministry of Science and Technology of Taiwan. We like to thank
Prof. T. M. Wu of NCHU for helpful suggestions in our spectral
interpretation, and Ms. Karin K. Kelley for her proofreading of
our manuscript.
REFERENCES
1
2
M. J. David, U.S. Patent 2,627,524, 1953.
M. Eissen, J. O. Metzger, E. Schmidt, U. Schneidewind,
Angew. Chem. Int. Ed. 2002, 41, 414–436.
B. Ochiai, Y. Satoh, T. Endo, J. Polym. Sci. Part A: Polym.
Chem. 2009, 47, 4629–4635.
3
FIGURE 7 TGA thermograms of the crosslinked NIPUs. [Color
figure can be viewed in the online issue, which is available at
wileyonlinelibrary.com.]
4
5
E. K. Drechsel, S. J. Groszos, U.S. Patent 2,802,022, 1957.
J. Guan, Y. Song, Y. Lin, X. Yin, M. Zuo, Y. Zhao, X. Tao, Q.
Zheng, Ind. Eng. Chem. Res. 2011, 50, 6517–6527.
S. Matsumura, Y. Soeda, K. Toshima, Appl. Microbiol. Bio-
technol. 2006, 70, 12–20.
J. Z. Hwang, S. C. Wang, P. C. Chen, C. Y. Huang, J. T. Yeh,
K. N. Chen, J. Polym. Res. 2012, 19, 1–10.
G. Chen, L. V. D. Does, A. Bantjes, J. Appl. Polym. Sci. 1993,
48, 1189–1198.
N. Kihara, T. Endo, J. Polym. Sci. Part A: Polym. Chem. 1993,
31, 2765–2773.
0 B. Ochiai, S. I. Sato, T. Endo, J. Polym. Sci. Part A: Polym.
Chem. 2007, 45, 3408–3414.
1 B. Ochiai, S. Inoue, T. Endo, J. Polym. Sci. Part A: Polym.
Chem. 2005, 43, 6613–6618.
6
the crosslinked polymers with an improved elongation
(
25%). In the TGA analysis, the 5 wt % degradation temper-
7
ature ranges from 190 to 297 8C for these crosslinked PUs,
and PUs which were cured by polyether diamines had a
much higher degradation temperature. (Fig. 7).
8
9
CONCLUSIONS
1
The poly(IPPC) which structurally possesses a linear repeat-
ing p-substituted-methylstyrene backbone has been newly
synthesized from bisphenol-A as the starting raw material.
Homopolymers of poly(IPPC) in a medium molecular weight
range (9500–25,000 g/mol) with isolated yield of over 80%
could be realized with trifluoromethanesulfonic acid as the
initiator at 240 8C. These polymers are characterized by
possessing side-chained propylene cyclic carbonates groups
at para-position of each phenylene ring. They possess high
Tg of up to 170 8C along with a Tm of 180–190 8C, which
reflects its structural homogeneity. The side-chained cyclic
carbonate of poly(IPPC) can be easily functionalized into
polyurethanes using ring-opening reactions with aliphatic
amines at around 100 8C. Furthermore, when poly(IPPC)
was modified into polyurethane at a high equivalent ratio of
diamines relative to cyclic carbonate, the resulting polymers
stay as stable solution throughout the reaction. Hence, the
ease of urethane formation from poly(IPPC)-diamine reaction
and non-gelling phenomenon of the crosslinked PU in NMP
both will provide substantial processing advantages for
film-making or coating operations. Further research on the
formulation optimization is in progress to enhance the physi-
cal properties of the crosslinked PUs and PU foams through
poly(IPPC) with various diamine combinations.
1
1
2 M. Bahr, R. Mulhaupt, Green Chem. 2012, 14, 483–489.
1
3 D. C. Webster, A. L. Crain, Prog. Org. Coat. 2000, 40, 275–
2
82.
1
4 T. Miyata, K. Matsumoto, S. Yonemori, S. Watanabe, T.
Endo, Nettowaku Porima. 2013, 34, 316–322.
5 H. Ito, C. G. Willson, J. M. J. Frechet, M. J. Farrall, E.
Eichler, Macromolecules 1983, 16, 510–517.
6 T. Hashimoto, M. Sawamoto, T. Higashimura, N. Saito, J.
Polym. Sci. Part A: Polym. Chem. 1987, 25, 1073–1084.
1
1
1
7 H. Schnell, H. Krimm, Angew. Chem. Int. Ed. 1963, 2, 373–
3
79.
1
8 W. F. Chen, H. Y. Lin, S. A. Dai, Org. Lett. 2004, 6, 2341–
2
343.
1
1
9 K. Heinrich, M. Helmut, S. Herman, U.S. Patent 3,327,019,
967.
2
0 V. Cal oꢀ , A. Nacci, A. Monopoli, A. Fanizzi, Org. Lett. 2002, 4,
2561–2563.
2
1 K. Kossev, N. Koseva, K. Troev, J. Mol. Catal. A: Chem.
2003, 194, 29–37.
22 M. M. Hossain, W. K. Huang, H. J. Chen, P. H. Wang, S. G.
Shyu, Green Chem. 2014, 16, 3013–3017.
808
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