Facile and scalable synthesis of nanoporous materials based on poly(ionic liquid)s

Article abstract of DOI:10.1002/cssc.201402593

A simple, fast, sustainable, and scalable strategy to prepare nanoporous materials based on poly(ionic liquid)s (PILs) is presented. The synthetic strategy relies on the radical polymerization of crosslinker-type ionic liquid (IL) monomers in the presence of an analogous IL, which acts as a porogenic solvent. This IL can be extracted easily after polymerization and recycled for further use. The great advantages of this synthetic approach are the atom-efficiency and lack of waste. The effects of different monomer/porogen ratios on the specific surface area, porosity, and pore size have been investigated. Finally, the potential of the materials as CO₂ sorbents has been evaluated.

Full text of DOI:10.1002/cssc.201402593

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DOI: 10.1002/cssc.201402593
Facile and Scalable Synthesis of Nanoporous Materials
Based on Poly(ionic liquid)s
[a]
[a]
[a]
[a]
[b]
Itxaso Azcune,* Ignacio Garcꢀa, Pedro M. Carrasco, Aratz Genua, Marek Tanczyk,
[b]
[b]
[a]
[a]
Manfred Jaschik, Krzysztof Warmuzinski, Germꢁn CabaÇero, and Ibon Odriozola*
A simple, fast, sustainable, and scalable strategy to prepare
nanoporous materials based on poly(ionic liquid)s (PILs) is pre-
sented. The synthetic strategy relies on the radical polymeri-
zation of crosslinker-type ionic liquid (IL) monomers in the
presence of an analogous IL, which acts as a porogenic sol-
vent. This IL can be extracted easily after polymerization and
recycled for further use. The great advantages of this synthetic
approach are the atom-efficiency and lack of waste. The effects
of different monomer/porogen ratios on the specific surface
area, porosity, and pore size have been investigated. Finally,
the potential of the materials as CO sorbents has been evalu-
2
ated.
Introduction
[
7]
Poly(ionic liquid)s (PILs) have emerged as a new class of func-
tional polymers with multiple applications in materials science,
CO transfer through the polymer matrix. However, this syn-
2
thetic strategy was time and energy consuming, and sacrificial
components were needed to generate the pores, which result-
ed in a low utilization efficiency of the starting materials. This
is not ideal, and modern synthetic chemists and materials sci-
entists are in pursuit of environmentally friendly processes that
are able to decrease resource and energy consumption as well
as to provide scalability.
such as solid ionic conductors, dispersants/stabilizers, CO ab-
2
[
1]
sorbents, and carbonaceous materials precursors. PILs derive
from IL monomers, and therefore, they combine the chemical
versatility of ILs with the spatial architecture and mechanical
properties inherent to polymers.
The porosity in polymers is a highly valued structural feature
for certain applications (gas storage and separation, catalysts,
Recently, an alternative strategy was reported for the prepa-
ration of mesoporous PILs through electrostatic complexation
[
2]
packaging materials in chromatography, etc). CO adsorbents
2
[8]
and absorbents with large surface areas have been investigat-
between PILs and polyacids. However, this approach was
only useful to provide materials with pendant carboxylate
anions and could not be tailored with any desired anions. Con-
sequently, scalable, straightforward, and versatile synthetic
strategies that provide mesoporous PILs are still required.
The use of porogenic solvents to create porous polymers
has been documented widely. ILs exhibit unique properties
that include negligible vapor pressure, nonflammability, high
ionic conductivity, a wide electrochemical window, and good
ed extensively because of their large CO sorption capacity
2
[
3]
and high sorption and desorption rates. Tang et al. showed
that PILs that have a porous structure presented a higher sur-
face area and faster CO sorption/desorption rates than those
2
[
4]
with nonporous structures. Nanoporous materials are classi-
fied according to their pore size by IUPAC as microporous (<
2
1
nm), mesoporous (2–50 nm), and macroporous (50–
000 nm). The synthesis of microporous PILs by the seed-swel-
[
5]
[9]
ling method has been reported recently. However, the majori-
ty of published studies have focused on the synthesis of mac-
chemical and thermal stability. These distinct properties make
them ideal candidates to replace harmful volatile organic sol-
vents to be used as reaction media in polymerization process-
[
6]
roporous PILs. Following the colloidal crystal templating strat-
egy, Wilke et al. showed that mesoporous PILs with an en-
[10]
es. ILs have become particularly useful for the synthesis of
2
À1
[11]
larged specific surface area (150–220 m g ) showed enhanced
molecularly imprinted polymers (MIPs) and for the creation
of porosity in the fabrication of sorbent phases for capillary mi-
[
12]
[13]
[
a] Dr. I. Azcune, Dr. I. Garcꢀa, Dr. P. M. Carrasco, Dr. A. Genua, G. CabaÇero,
Dr. I. Odriozola
Materials Division
IK4-CIDETEC Research Centre
Paseo Miramꢁn 196, 20009 Donostia-San Sebastiꢂn (Spain)
E-mail: iazcune@cidetec.es
croextraction and monolithic stationary phases. The use of
ILs as solvents for the synthesis of (hyper-)crosslinked poly-
[14]
[15]
mers, both neutral and ionic, has also been reported. Pav-
lova et al. prepared porous hyper-crosslinked hydrophilic net-
works by the simultaneous alkylation and polymerization of 4-
vinylpyridine in 1-butyl-3-methylimidazolium tetrafluorobo-
iodriozola@cidetec.es
[15]
[b] Dr. M. Tanczyk, Dr. M. Jaschik, Prof. K. Warmuzinski
rate. The anion of the resulting porous PIL was the leaving
group of the corresponding alkylation reagent. Further struc-
tural modification of such polymers by standard anion-ex-
change procedures is troublesome and difficult. For example, if
the incorporation of fluorinated anions such as bis(triflurosulfo-
Institute of Chemical Engineering
Polish Academy of Sciences
ul. Baltycka 5, 44-100 Gliwice (Poland)
Supporting Information for this article is available on the WWW under
http://dx.doi.org/10.1002/cssc.201402593.
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nyl)imide (TFSI) is desired to confer hydrophobicity to the ma-
terial. This anion might be of interest for certain applications,
such as postcombustion CO capture, in which water might
2
compete in the absorption process. As acknowledged recently,
the impact of water coadsorption with CO in microporous or-
2
[
16]
ganic polymer (MOP) sorbents is dramatic. The performance
of hydrophobic MOPs in terms of CO uptake is less affected
2
by moisture than that of their hydrophilic analogues, which
show decreases of 5 and 50%, respectively.
In this paper we describe a simple, scalable, and universal
approach for the synthesis of nanoporous materials based on
PILs. To this end, we have explored the radical polymerization
of bisvinyl-ended ILs in the presence of analogous nonpoly-
merizable ILs, which act as porogenic solvents and can be ex-
tracted easily after polymerization for reuse. It is known that
porogenic solvents control the porous properties of the mono-
lith through the solvation of the polymer chains in the reaction
[
17]
Scheme 1. Synthetic pathway for nanoporous PILs.
medium. Small pores are created if the monomers and poro-
genic solvents are miscible, whereas macropores result from
systems that present poor miscibility. In this sense, ILs that
have the same chemical nature as PILs might be regarded as
ideal solvents to obtain materials with small pores. The princi-
pal advantages of this synthetic approach are the atom-effi-
ciency and lack of waste, as all the reagents and solvents can
be recycled. In addition, we have investigated the effect of the
percentage of the porogenic solvent on the properties of the
porous PIL. The chemical and thermal properties of the PILs
were analyzed by FTIR spectroscopy and thermogravimetric
analysis (TGA). The surface morphologies of the products were
determined by field-emission scanning electron microscopy
(
FE-SEM), and N adsorption–desorption measurements were
2
performed to determine the specific surface area, average pore
size, and porosity of the materials. Finally, the CO uptake of
2
the samples was measured.
Results and Discussion
The studied crosslinkable IL monomer was prepared by the re-
action of 1-vinylimidazole with 1,4-dibromobutane followed by
a standard anion-exchange procedure with a hydrophobic
LiTFSI salt (Scheme 1).
1-Butyl-3-methylimidazolium
bis(trifluoromethylsulfonyl)i-
mide was selected as the porogen IL as it is chemically similar
to the monomer, which thus ensures compatibility and good
miscibility. Different monomer/porogen weight ratios (M/P=
1
:0, 1:0.5, 1:1, 1:2, 1:3, 1:5, and 1:10) were used to investigate
the effect of concentration on the formation of the porous PIL.
The polymerization reactions were performed upon addition of
a radical initiator, azobisisobutyronitrile (AIBN; 2 wt%), by heat-
ing at 1008C for 24 h. The solidified porous material was then
washed repeatedly with acetone in a centrifugal vessel and
dried under vacuum (95–98% yield). Interestingly, the IL was
recovered quantitatively (100% yield) by evaporation of the
Figure 1. a) FTIR spectra of the M and P. b) Magnification of the 1750–
À1
1400 cm region of the FTIR spectra of M, P, and PIL samples.
porogen presented the characteristic bands of the TFSI anion
À1
at n˜ =1347, 1328, 1179, 1132, and 1050 cm (Figure 1a). The
À1
bands between n˜ 2879 and 2965 cm were attributed to the
CÀH stretch of the butyl side-chain of the porogen, whereas
1
À1
acetone with high purity as shown by H NMR analysis (Figur-
the signals above n˜ 3000 cm belonged to the imidazole ring
es S2 and S3).
and CÀH stretch of the vinyl group. In addition, the monomer
À1
FTIR spectroscopy was performed to investigate the pres-
ence of unreacted vinyl groups. Both the monomer and the
presented characteristic bands at n˜ 1675–1650 and 1600 cm ,
which correspond to the C=C stretch of the vinyl group, which
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the application of the Brunauer-
Emmett-Teller (BET) theory are
depicted in Figure 4a. The larg-
est surface area was exhibited
2
À1
by PIL1:1 (86.2 m g ) followed
2
À1
by PIL1:2 (20.10 m g ). The
values for the other samples
were close to that of PIL , syn-
1
:0
thesized in bulk. According to
these results, there should be an
optimum M/P ratio that would
provide the required degree of
crosslinking to ensure a perma-
nent
nanoporous
structure.
Beyond that dilution, the forma-
tion of a stable nanostructure
was not detected by the analyti-
cal techniques used. The hyste-
resis of the isotherm of PIL ,
Figure 2. Swelling test in water and acetone. PIL samples from left to right: PIL1:0, PIL1:0.5, PIL1:1, PIL1:2, PIL1:3, PIL1:5
and PIL1:10. a) Dry PIL samples. b) PIL samples in water. c) PIL samples in acetone. d) Percentage of swelling of PIL
samples in acetone.
,
1
:1
classified as type IV, indicated
can be used to ascertain the degree of polymerization. This set
of signals did not arise in the FTIR spectra of the PILs, which
proves that the polymerization occurred quantitatively
the presence of capillary condensation (Figure 4b). Barret–
Joyner–Halenda (BJH) theory predicts an adsorption average
pore diameter of 8.5 nm and a desorption average pore diame-
(Figure 1). All polymers showed similar absorption spectra as
they had the same chemical composition. In addition, all the
PILs prepared in the presence of the porogen showed the
same FTIR spectra as PIL , which confirms the complete elimi-
1
:0
nation of the porogen in the washing step.
Once the porous PILs from different M/P ratios were pre-
pared, their swelling behavior was studied. Dry samples ar-
ranged in order of the increasing amount of porogen from
PIL1:0 to PIL1:10 are shown in Figure 2a. The samples presented
very limited swelling in water, probably because of the pres-
ence of hydrophobic TFSI anions (Figure 2b). In contrast, the
samples showed a nonlinear degree of swelling in acetone
(Figure 2c). Here, the degree of swelling showed a linear in-
crease (correlated to the porogen quantity) until a maximum
of 500 vol% was reached for PIL . If the amount of porogen
1
:5
was doubled (PIL1:10), a decrease of the swelling volume was
observed clearly (Figure 2d). This could be explained by the di-
lution of the monomer in the mixture, which avoids the forma-
tion of a highly cross-linked network.
The porous morphology of the PILs was analyzed by FE-SEM
under the same experimental conditions to enable a direct
comparison (Figure 3). All the PILs synthesized in the presence
of porogen exhibited a nanoporous sponge-like surface mor-
phology, in contrast to the smooth surface of PIL , synthe-
1
:0
sized in bulk in the absence of the porogenic solvent. Follow-
ing the IUPAC criteria for nanoporous materials, the vast major-
ity of the detected pores fell into the mesoporous type. In the
case of PIL1:1 and PIL , the presence of macropores was also
1:2
observed. However, the existence of micropores could not be
determined by this technique because of the insufficient reso-
lution of the FE-SEM microscope.
N adsorption isotherms were measured at 77 K to deter-
2
mine the specific surface area, average pore size, and porosity
of the materials. The specific surface area values obtained by
Figure 3. FE-SEM micrographs of PIL1:0, PIL1:0.5, PIL1:1, PIL1:2, PIL1:3, PIL1:5, and
PIL1:10. Scale bar corresponds to 200 nm in all cases.
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gen) may disintegrate and thus, the surface area may not in-
crease with an increase in the porogen mass fraction. The po-
rosity of PIL1:1 was calculated to be roughly 22%.
Although the obtained surface area values were lower than
those reported for materials obtained through the hard-tem-
plating pathway, for which specific surface areas of 150–
2
À1
[7]
2
20 m g were reported, the present methodology still re-
mains valuable from the point of view of preparation efficiency
and practical convenience. The values of the surface area, pore
diameter, adsorption kinetics, and CO2 uptake are listed in
Table 1.
Table 1. List of the synthesized PILs and their surface area, pore diameter,
adsorption kinetics, and CO uptake.
2
[a]
[c]
2
PILM/P P/M BETsurface area Pore diameter Time constant [CO ]
2
À1
[b]
À1
[
m g
]
[nm]
(t) [s]
[molkg ]
PIL1:0
PIL1:0.5
PIL1:1
PIL1:2
PIL1:3
PIL1:5
0
0.00
–
–
2877.22
323.67
32.82
0.057
0.083
0.098
0.100
0.095
0.081
0.074
0.5 0.08
1
2
3
5
86.21
20.10
0.00
0.06
0.11
8.5–6.8
7.3–4.0
–
–
–
69.67
1545.25
1920.26
564.05
PIL1:10 10
[
a] In the case of negligible surface area, the values of pore diameters
were not considered. [b] Time constant at 400–600 mbar and 208C.
c] CO concentration at 1 bar and 208C.
[
2
The CO uptake and adsorption kinetics of the seven PILs
2
were then investigated. Before the measurements the samples
À6
were degassed for 24 h under high vacuum (10 mbar) at
908C. Only a minor decrease in mass during degassing was ob-
served (0.9 to 1.7%). The CO adsorption isotherms measured
2
at 293 K are shown in Figure 5a. The largest uptake was ach-
ieved by the polymers with the largest surface areas, PIL and
1
:1
À1
PIL1:2 (0.1 molkg ), but an almost identical value was reached
by PIL , which showed a negligible surface area. The uptake
1
:3
decreased for PIL1:5 and PIL1:10, and the lowest value was ob-
À1
served for PIL1:0 (0.06 molkg ). The results showed that the
uptake of CO was not related solely to the surface area, which
2
suggests that the CO uptake is not an adsorption phenomen-
2
on but rather absorption in the polymer matrix. These observa-
[4a]
tions are in accordance with the results of Tang et al. and
[7]
Wilke et al. for a variety of nonporous and mesoporous PILs.
Tang et al. stated plainly that the CO sorption capacity de-
2
pends mainly on the chemical structure of PILs, whereas the
rate of CO sorption is affected by the surface area of the poly-
2
mers. The larger the surface area, the shorter the time required
to reach the absorption equilibrium. The absorption kinetics of
each PIL are depicted in Figure 5b. It was observed clearly that
the equilibrium was reached 80 times faster by PIL1:1 than by
the PILs with negligible surface areas, such as PIL . These re-
2
Figure 4. a) BET surface area versus porogen proportion. b) N adsorption–
desorption isotherms of mesoporous PIL1:1 measured at 77 K. c) Pore size dis-
tribution and cumulative pore volume.
1
:0
À1
ter 6.8 nm (4 VA ; Figure 4c). Although these values are small-
sults are consistent with the hypothesis that the sorption into
the highly crosslinked PIL1:0 was much slower than into the
mesostructured PILs. However, by increasing the surface area
er than those achieved for materials obtained by hard-templat-
[
7]
ing pathways, they are still within the mesoporous range. Ac-
[
7]
cording to Wilke et al., the pore size depends on the tem-
plate size and stability of the porous structure obtained,
among other factors. Unstable structures obtained with
a higher mass fraction of the template (or, in our case, poro-
by four times, PIL1:2 and PIL , the kinetics was only twice
1:1
faster. Clearly, the experiments showed that, for the materials
2
À1
studied, even a small surface area such as 20 m g was suffi-
cient from the standpoint of the rate of CO transport and the
2
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within the values reported in the literature, with enhanced ki-
netics for the porous materials. The sorption capacity of the
materials could be further enhanced by modifying the chemi-
cal structure of the IL monomers by selecting cation, anion,
and core structure with higher affinity towards CO , for exam-
2
[19]
ple, by increasing the ion polarity.
Conclusions
A simple and rapid synthetic procedure to prepare nanoporous
poly(ionic liquid)s using ionic liquids (ILs) as porogens is de-
scribed. The proposed strategy is robust and scalable (batches
of 30 g have been prepared). In addition, no waste material is
generated, and the porogen is recovered and recycled. Like-
wise, the synthetic advantages overcome some difficulties that
other approaches might face in terms of scalability, energy
consumption (e.g., sintering of hard templates), and safety
(
e.g., the use of harmful volatile solvents). Moreover, the tailor-
able structure of an IL makes it possible to design the most
compatible IL porogen for each IL monomer. Therefore, this
approach could be extended easily to the synthesis of poly(-
ionic liquid)s with other chemical structures with higher a affini-
ty towards CO uptake. Further investigation in this sense is in
2
progress.
Experimental Section
Materials and methods
1
,4-Dibromobutane (99%) and 1-vinylimidazole (99%) were pur-
2
Figure 5. a) CO adsorption isotherm of the PILM/P samples at 293 K. b) 1/t (t,
time constant) vs. P/M ratio.
chased from Sigma–Aldrich. AIBN (98%) was purchased from Acros
Organics. Acetone (99.5%), acetonitrile, and ethyl acetate were
purchased from Scharlab. 1-Butyl-1-methylimidazolium chloride
and bis(trifluoromethane)sulfonimide lithium salt (LiTFSI) were pur-
chased from IoLiTec. IR spectra were recorded by using an ATR-
FTIR Jasco 4100 spectrometer. NMR spectra were recorded by
using a Bruker Avance III NMR spectrometer in appropriate deuter-
ated solvents. TGA was performed by using a Q500 TG-DTA ana-
sorption capacity of these materials. Thus, it is not always ad-
visable to maximize the surface area at all cost.
In this study, polymers based on imidazolium and TFSI
anions were synthesized as a proof-of-concept of a new prepa-
lyzer manufactured by TA Instruments in the temperature range
between 25 and 6008C under N at a heating rate of 108Cmin
ration method for nanoporous PILs. The CO sorption capaci-
2
À1
2
ties of these PILs were comparable to literature values, and we
(Supporting Information). A Carl Zeiss Ultra Plus field-emission
were mindful that the CO loading capacity of a given PIL de-
2
scanning electron microscope was used to compare the morpholo-
pends on temperature and pressure. Therefore, measurement
conditions must be taken into account if literature values are
compared directly. CO2 loading capacities of imidazolium-
based nonporous PILs have been reported in the range of
gy of the obtained polymers. The N adsorption isotherms meas-
urements were performed at 77 K by using a Micromeritics ASAP
2
2020 analyzer. The CO adsorption isotherm measurements at were
2
performed at 298 K by using a Hiden Isochema IGA-003 gravimetric
analyzer (Supporting Information).
À1
À
1
.53–3.31 mgCO2 gPIL for TFSI and PF6 anions, respectively,
À1
and up to 12.46 mgCO2 gPIL for the PIL with acetate anions at
[
18]
258C and atmospheric pressure. In addition, Wilke et al. re-
Preparation of 1,4-di(N,N’-vinylimidazolium)butane di-
ported nonporous, highly cross-linked, imidazolium TFSI-based
[
bis(trifluoromethanesulfonyl)imide] (M)
À1
PILs with a loading capacity of 5.2 mg gPIL
at 08C and at-
CO2
[
7]
mospheric pressure. For nonporous PIL , CO loading capaci-
To a solution of 1-vinylimidazole (420 mmol, 39.9 g) in acetonitrile
(150 mL) at 608C was added 1,4-dibromobutane (200 mmol,
43.6 g) dropwise. After 24 h, the product was precipitated, washed
in ethyl acetate, and dried under reduced pressure. The reaction
yielded 77.8 g (96%) of white powder. The resulting dibromide salt
1
:0
2
À1
À1
À1
ties of 2.64 mg gPIL
(0.06 molkg ) and 4.18 mg gPIL
CO2
CO2
À1
(
0.095 molkg ) were measured at 20 and 08C, respectively,
under the same pressure (Supporting Information). The CO2
uptake of a given PIL is decreased by increasing the tempera-
ture. In our experiments, the sorption capacity of PIL1:0 at 208C
was reduced by 60% compared to that at 1 bar and 08C. In
(91.55 mmol, 37.0 g) was dissolved in deionized water (400 mL),
and a solution of LiTFSI (201.0 mmol, 57.7 g) in deionized water
(50 mL) was added. After 1 h, the solid was collected by filtration
and washed thoroughly with deionized water. The reaction yielded
any case, the CO uptake values reported in this paper fall
2
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1
7
0 g (98%) of white powder. M.p. 83.198C; H NMR (500 MHz,
Keywords: absorption · ionic liquids · materials science ·
mesoporous materials · polymers
CDCl , 258C, Me Si): d=9.43 (s, 2H, CH), 8.20 (s, 2H, CH), 7.90 (s,
3
4
3
2
H, CH), 7.29 (dd, J(H,H)=15.6 Hz, 8.7 Hz, 2H, CH), 5.94 (dd,
3
3
J(H,H)=2.4 Hz, 15.6 Hz, 2H, CH ), 5.44 (dd, J(H,H)=8.7 Hz, 2.4 Hz,
2
2
H, CH ), 4.23 (m, 4H, CH ), 1.84 ppm (m, 4H, CH ).
2 2 2
[
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1
7.47 g) in deionized water (100 mL) was added a solution of
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[
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oil. H NMR (500 MHz, CDCl , 258C, Me Si): d=8.73 (s, 1H, CH), 7.30
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3
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3
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2
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(
s, 3H, CH ), 1.84 (m, 2H, CH ), 1.36 (m, 2H, CH ), 0.95 ppm (t,
J(H,H)=7.4 Hz, 3H, CH3).
3
2
2
3
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[
[
General procedure for the synthesis of PILs
M, P, and AIBN were blended together. The homogenous mixture
2
010, 46, 967–969; c) X. Hu, J. Huang, W. Zhang, M. Li, C. Tao, G. Li,
was degassed and kept under a N atmosphere. The mixture was
2
Adv. Mater. 2008, 20, 4074–4078; d) F. Yan, J. Texter, Angew. Chem. Int.
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then heated to 1008C for 24 h. The resulting composite material
was then transferred to a centrifuge vessel and washed with ace-
tone until the total weight of IL porogen (100%) was recovered.
The solid was dried under vacuum.
[
[
Synthesis of PIL1:0: The general procedure was followed starting
from M (35 g) and AIBN (0.70 g) to give 33.5 g of PIL1:0 (96% yield).
Synthesis of PIL1:0.5: The general procedure was followed starting
from M (7 g), P (3.5 g), and AIBN (0.14 g) to give 6.65 g of PIL1:0.5
[
9] N. V. Plechkova, K. R. Seddon, Chem. Soc. Rev. 2008, 37, 123–150.
[
[
10] P. Kubisa, Prog. Polym. Sci. 2004, 29, 3–12.
(
95% yield).
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355; b) A. M. Shearrow, G. A. Harris, L. Fang, P. K. Sekhar, L. T. Nguyen,
E. B. Turner, S. Bhansali, A. Malik, J. Chromatogr. A 2009, 1216, 5449–
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6, 4549–4556; b) A. I. Cooper, K. Scott, P. Sneddon, N. Winterton,
Synthesis of PIL1:1: The general procedure was followed starting
from M (37 g), P (37 g), and AIBN (0.74 g) to give 35.6 g of PIL1:1
(
96% yield).
Synthesis of PIL1:2: The general procedure was followed starting
from M (7 g), P (14 g), and AIBN (0.14 g) to give 6.74 g of PIL1:2
3
[
(
96% yield).
6
Synthesis of PIL1:3: The general procedure was followed starting
from M (7 g), P (21 g), and AIBN (0.14 g) to give 6.79 g of PIL1:3
5
[
(
97% yield).
7
Synthesis of PIL1:5: The general procedure was followed starting
from M (7 g), P (35 g), and AIBN (0.14 g) to give 6.86 g of PIL1:5
3
Polym. Prepr. 2004, 45, 291–292; c) L. Peng, J. Zhang, J. Li, B. Han, Z.
Xue, G. Yang, Angew. Chem. Int. Ed. 2013, 52, 1792–1795; Angew. Chem.
2013, 125, 1836–1839; d) Y.-H. Shih, B. Singco, W.-L. Liu, C.-H. Hsu, H.-Y.
Huang, Green Chem. 2011, 13, 296–299; e) L. Zhu, C.-Y. Huang, Y. H.
Patel, J. Wu, S. V. Malhotra, Macromol. Rapid Commun. 2006, 27, 1306–
(
98% yield).
Synthesis of PIL1:10: The general procedure was followed starting
from M (20 g), P (200 g), and AIBN (0.40 g) to give 19.6 g of PIL1:10
(
98% yield).
1311.
[
[
15] L. A. Pavlova, M. V. Pavlov, V. A. Davankov, Dokl. Chem. 2006, 406, 6–8.
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Adams, A. I. Cooper, J. Am. Chem. Soc. 2012, 134, 10741–10744.
Acknowledgements
[
[
17] C. Viklund, F. Svec, J. M. J. Frꢄchet, Chem. Mater. 1996, 8, 744–750.
18] E. I. Privalova, E. Karjalainen, M. Nurmi, P. Mꢃki-Arvela, K. Erꢃnen, H.
Tenhu, D. Y. Murzin, J.-P. Mikkola, ChemSusChem 2013, 6, 1500–1509.
19] R. S. Bhavsar, S. C. Kumbharkar, U. K. Kharul, J. Membr. Sci. 2012, 389,
The authors acknowledge financial support from the European
Commission through the INTERACT project funded by the Europe-
an Union’s Seventh Framework Program for Research, Technolog-
ical Development and Demonstration under grant agreement
number 608535. The authors acknowledge the collaboration of
SOLVIONIC in the framework of the PIL-TO-MARKET project (FP7-
PEOPLE-IAPP-2008-230747).
[
3
05–315.
Received: June 26, 2014
Revised: July 30, 2014
Published online on && &&, 0000
ꢂ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
ChemSusChem 0000, 00, 1 – 7
&
6
&
ÞÞ
These are not the final page numbers!

FULL PAPERS
Jagged little PIL: We present a very
simple and convenient strategy to pre-
pare nanoporous poly(ionic liquid)s
I. Azcune,* I. Garcꢀa, P. M. Carrasco,
A. Genua, M. Tanczyk, M. Jaschik,
K. Warmuzinski, G. CabaÇero,
I. Odriozola*
(PILs) in a sustainable and scalable
manner. An ionic liquid (IL) analogous
to the polymerizable IL is used as the
solvent and porogen, which can be ex-
tracted after polymerization and recy-
cled for further use. The resulting nano-
porous materials have been investigat-
&
& – &&
Facile and Scalable Synthesis of
Nanoporous Materials Based on
Poly(ionic liquid)s
ed as CO sorbents.
2
ꢂ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
ChemSusChem 0000, 00, 1 – 7
&
7
&
ÞÞ
These are not the final page numbers!