XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
142
T1: P–9
FT-IR and FT-Raman studies of cross-linking processes
with glutaraldehyde and microwave radiation for polymer composition
of poly(acrylic acid)/carboxymethyl cellulose (PAA/CMC)
Beata Grabowska
1
, Maciej Sitarz
2
, Karolina Kaczmarska
1
, and Alena Pribulová
3
1
AGH University of Science and Technology, Faculty of Foundry Engineering, Reymonta 23, 30 059
Cracow, Poland beata.grabowska@agh.edu.pl
2
AGH University of Science and Technology, Faculty of Materials Science and Ceramics,
Mickiewicza 30, 30–059 Cracow, Poland
3
Technical University of Košice, Department of Ferrous Metallurgy and Foundry, Letna 9.042 00
Košice, Slovakia
The spectroscopic FT-IR and FT-Raman methods confirmed the possibility of cross-linking
of the poly(acrylic acid)/carboxymethyl cellulose composition (PAA/CMC) by the selected
chemical (glutaraldehyde) and physical agents (microwave field). Glutaraldehyde (OHC–
(CH
2
)
3
–CHO) can generate the cross-linking bonds formation between polymer chains by means
of the addition reaction in the carbonyl group with the participation of hydroxyl groups, present
in the CMC structure and the formation of hemiacetal or acetal groups.
In the microwave radiation field (800 W, 2.45 GHz) the resonance stabilisation will be
disturbed in the carboxyl group and the hydroxyl fragment in this group will be the substituent
easier for splitting off. Therefore under the influence in microwave field the cross-linking
reaction occurs by the PAA dehydration. The supplied energy is sufficient for transferring a part
of the microwave energy into heat as well as for the resonance excitation to rotations of polar
groups within the composition polymer chains (carboxylic, carboxylate and hydroxyl groups)
and the formation the stable cross-linked structures with the participation of intermolecular
hydrogen bonds.
The obtained knowledge of the cross-linking process will make it possible to conduct further
research in the foundry engineering of the forming and consolidating polymer-silicate systems
with the method of 3D printing.
Keywords: poly(acrylic acid); carboxymethyl cellulose; polymer composition; cross-linking, glutaraldehyde;
microwave; spectroscopy
Acknowledgment
The work was supported by the Project AGH No 11.11.170.318/13
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
143
T1: P–10
Sulfamates and methanesulfonates of L-arginine and L-histidine
Aram M. Petrosyan
1
, Vahram V. Ghazaryan
1
, Gerald Giester
2
, and Michel Fleck
2
1
Crystal growth lab, Institute of Applied Problems of Physics, NAS of Armenia, 25 Nersessyan Str.,
0014 Yerevan, Armenia, e-mail: aram.m.petrosyan@gmail.com
2
Institute of Mineralogy and Crystallography, University of Vienna, Althanstr. 14, A-1090 Vienna,
Austria
Salts of L-arginine and L-histidine are the most studied among salts of amino acids [1].
However, methanesulfonates of L-arginine and L-histidine are not known and only
spectroscopic characterization of L-histidinium sulfamate was communicated without details of
crystal structure [2]. In the present work, we report our results on obtaining, crystal growth,
structure determination at 200 K and spectroscopic characterization of sulfamate and
methanesulfonate salts of L-arginine and L-histidine.
The salt (L-ArgH)(NH
2
SO
3
) crystallizes in the triclinic space group P1, Z=2 (a=5.7026(2) Å,
b
=8.5315(3) Å, c=12.1240(4) Å, α=89.604(2)°, β=87.254(2)°, γ=79.738(2)°). Protonated
guanidyl and amino groups of L-ArgH cations as well as NH
2
groups of sulfamate anions form
N-H···O hydrogen bonds with COO carboxylate groups of cations and SO
3
groups of anions.
The salt (L-HisH)(NH
2
SO
3
) crystallizes in the orthorhombic space group P2
1
2
1
2
1
, Z=4
(a=4.9729(2) Å, b=8.2645(3) Å, c=25.1111(8) Å). Protonated imidazole and amino groups of
the L-HisH cation as well as the NH2 group of the sulfamate anion form N-H···O hydrogen
bonds with COO carboxylate groups of cation and SO
3
group of anion. ATR-IR spectrum
registered by us differs from IR spectrum shown in [2] registered by KBr pellet technique. In
addition to (L-HisH)(NH
2
SO
3
) we obtained also a new salt (L-HisH
2
)(NH
2
SO
3
)
2
in this system.
The salt (L-HisH
2
)(NH
2
SO
3
)
2
crystallizes in the monoclinic space group P2
1
, Z=2
(a=5.0188(2) Å, b=8.6042(3) Å, c=15.0165(6) Å, β=93.159(2)°). The carboxyl group COOH of
the L-HisH
2
cation forms O-H···O hydrogen bond with one of SO
3
group of anions. Remaining
hydrogen bonds are N-H···O type formed by protonated imidazole, amino group as well as NH
2
groups of sulfamate anions.
Two salts were found in the L-arginine-CH
3
SO
3
H-H
2
O system: (L-ArgH)(CH
3
SO
3
) and (L-
ArgH
2
)(CH
3
SO
3
)
2
. The first crystallizes with highest symmetry (space group P6
5
22, Z=12,
a
=b=9.2740(1) Å, c=52.7314(15) Å, γ=120.00°) observed among salts of amino acids, while the
second one crystallizes in lowest symmetry (space group P1, Z=2, a=5.2528(2) Å, b=10.3678(3)
Å, c=15.8737(5) Å, α=105.922(2)°, β=94.522(2)°, γ=93.978(2)°).
In the system L-histidine-CH
3
SO
3
H-H
2
O also two salts were found: (L-
HisH)(CH
3
SO
3
)·2H
2
O and (L-HisH
2
)(CH
3
SO
3
)
2
. Both are monoclinic with space group P21 and
Z=8, a=9.2990(3) Å, b=18.8237(5) Å, c=15.2750(4) Å, β=98.538(2)° and Z=2, a=6.1016(1) Å,
b
=7.3693(2) Å, c=16.1581(4) Å, β=92.6210(10)°, respectively. Vibrational spectra contain
characteristic modes of singly and doubly charged L-HisH and L-HisH
2
cations, the
methanesulfonate anion as well as of hydrogen bonds present in the structures.
Keywords: sulfamate; methanesulfonate; L-arginine; L-histidine; vibrational spectroscopy; crystal structure
References
[1] M. Fleck, A.M. Petrosyan, Salts of amino acids: crystallization, structure and properties. Springer,
Dordrecht, 2014.
[2] Beulah J.M. Rajkumar, V. Ramakrishnan, S. Asath Bahadur, J. Raman Spectr. 30 (1999) 589.
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