Synthesis, spectral, and antibacterial screening studies of chelating polymers of bisphenol-A-formaldehyde resin bearing barbituric acid

Article abstract of DOI:10.1080/00958971003728296

A new polymeric ligand was synthesized by the reaction of bisphenol-A and formaldehyde in the basic medium, followed by condensation polymerization with barbituric acid in the acidic medium. Polymer metal complexes were prepared by reaction of this resin with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II). The polymeric resin and its metal polychelates were characterized by elemental analysis, FT-IR, ¹³C-NMR, and ¹H-NMR spectra. The geometry of the polymer metal complexes was evaluated by electronic spectra (UV-Vis) and magnetic moment measurement. Thermal stabilities show an increased thermal stability of the metal polychelates compared to the ligand. The antibacterial activities of all the synthesized polymers were investigated against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli, showing good antibacterial activities against these bacteria. Cu(II) polychelate showed highest biocidal activity.

Full text of DOI:10.1080/00958971003728296

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Synthesis, spectral, and antibacterial
screening studies of chelating polymers
of bisphenol-A–formaldehyde resin
bearing barbituric acid
Nahid Nishat a , M. Zulfequar b , Asma a & Sumaiya Hasnain a
a Department of Chemistry , Jamia Millia Islamia University , New
Delhi 110025, India
b Department of Physics , Jamia Millia Islamia University , New
Delhi 110025, India
Published online: 30 Mar 2010.
To cite this article: Nahid Nishat , M. Zulfequar , Asma & Sumaiya Hasnain (2010) Synthesis,
spectral, and antibacterial screening studies of chelating polymers of bisphenol-A–formaldehyde
resin bearing barbituric acid, Journal of Coordination Chemistry, 63:7, 1273-1281, DOI:
10.1080/00958971003728296
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Journal of Coordination Chemistry
Vol. 63, No. 7, 10 April 2010, 1273–1281
Synthesis, spectral, and antibacterial screening studies
of chelating polymers of bisphenol-A–formaldehyde
resin bearing barbituric acid
NAHID NISHAT*y, M. ZULFEQUARz, ASMAy and SUMAIYA HASNAINy
yDepartment of Chemistry, Jamia Millia Islamia University, New Delhi 110025, India
zDepartment of Physics, Jamia Millia Islamia University, New Delhi 110025, India
(Received 11 July 2009; in final form 9 November 2009)
A new polymeric ligand was synthesized by the reaction of bisphenol-A and formaldehyde
in the basic medium, followed by condensation polymerization with barbituric acid in the acidic
medium. Polymer metal complexes were prepared by reaction of this resin with Mn(II), Co(II),
Ni(II), Cu(II), and Zn(II). The polymeric resin and its metal polychelates were characterized by
elemental analysis, FT-IR, 13C-NMR, and 1H-NMR spectra. The geometry of the polymer
metal complexes was evaluated by electronic spectra (UV-Vis) and magnetic moment
measurement. Thermal stabilities show an increased thermal stability of the metal polychelates
compared to the ligand. The antibacterial activities of all the synthesized polymers were
investigated against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli, showing
good antibacterial activities against these bacteria. Cu(II) polychelate showed highest biocidal
activity.
Keywords: Barbituric acid; Polymer metal complexes; Thermogravimetric analysis
1. Introduction
Metal containing polymers show many potential applications as functional materials
with desirable chemical and physical properties, catalytic activities [1, 2], and models for
bioinorganic systems [3]. After the discovery of barbituric acid by Adolf von Baeyer in
1864, it was concluded that barbituric acid is not pharmacologically active, but its
derivatives could be used as drugs, valuable in medicine as soporifics, hypnotics,
sedatives, and anesthetics [4]. Barbituric acid is nontoxic and thermally stable [5].
The presence of potential donors such as two amine nitrogens and three carbonyl oxygens
makes barbiturates interesting and polyfunctional ligands [6], suitable candidates for
pharmacologically active and useful ligands in coordination and polymer chemistry.
This article reports the synthesis and characterization of bisphenol-A–formaldehyde
resin according to the reported method, and its condensation polymerization to
obtain the polymeric ligand (BFB) containing barbituric acid moiety. Mn(II),
Co(II), Ni(II), Cu(II), and Zn(II) were added to BFB to obtain metal polychelates.
*Corresponding author. Email: nishat_nchem08@yahoo.com
Journal of Coordination Chemistry
ISSN 0095-8972 print/ISSN 1029-0389 online ß 2010 Taylor & Francis
DOI: 10.1080/00958971003728296

1274
N. Nishat et al.
The spectral, magnetic, thermal properties, the type of chelation of the ligand, and
the geometry around the metal center are discussed. In addition, the antimicrobial
activities are tested against several bacteria, Bacillus subtilis, Staphylococcus aureus
(Gram-positive) and Escherichia coli (Gram-negative).
2. Experimental
2.1. Chemicals
The following materials were used as received: bisphenol-A (G.S. Chemicals),
formaldehyde (37–41%) (S.D. Fine Chemicals), barbituric acid, sodium hydroxide
pellets (Merck India), and metal(II) acetate (Qualigens Fine Chemicals, India). Solvents
such as dimethyl sulfoxide (DMSO) and dimethyl formamide (DMF) (Qualigens
Fine Chemicals) were of analytical grade and used without purification.
2.2. Preparation of bacterial strains
The antibacterial activities of the ligand and metal polychelates were screened in vitro
against various bacteria in DMSO. The sample concentration was 20 mg mLꢀ1
.
Antibacterial activity was screened against B. subtilis, S. aureus (Gram positive) and
E. coli (Gram negative) bacteria by the shaking flask method [7] and the number of
viable cells was counted utilizing the spread plate method [8]. One loop full of bacteria
was inoculated in 10 mL of a nutrient broth (peptone, 5 g Lꢀ1; pH 6.8) and incubated at
37ꢁC for 28 h in a test-tube shaker at 100 rpm. The nutrient agar (20 mL) was poured
into sterile Petri plates and allowed to solidify at room temperature. After solidification,
0.1 mL of the bacterial culture was spread on the agar. A circular well was made at the
center of each Petri plate with a sterilized steel borer. The test samples were prepared in
DMSO at 20 mg mLꢀ1, and 0.1 mL of each test solution was added to the well and
incubated at 37ꢁC for 24 h. After incubation, the zones of inhibition were measured
in millimeters and represented as inactive, mildly active, moderately active, and highly
active depending on the diameter and clarity of the zone of inhibition. Kanamycin was
used as positive control and DMSO as negative control.
2.3. Instrumentations
Elemental analyses (C, H, and N) were carried out on an elemental analyzer system
GmbH Vario ELIII with the percentage of metal obtained by complexometric titration
with EDTA after decomposing with conc. HNO3 at room temperature, the results are
given in table 1. Magnetic susceptibility measurements were recorded on a Vibrating
Sample Magnetometer model 155 at room temperature. FT-IR spectra were obtained
on a Perkin Elmer IR spectrophotometer model 621 using KBR pellets. Proton NMR
(1H-NMR) and carbon (13C-NMR) nuclear magnetic resonance spectra were recorded
on a JEOL-GSX 300 MHz FX 1000 FT-NMR spectrometer using DMSO-d6 and
tetramethylsilane (TMS) as an internal standard. UV-Visible spectra were carried out
on a Perkin Elmer Lambda EZ-201 spectrophotometer in DMSO.

Bisphenol-A–formaldehyde resin
Table 1. Elemental analysis data for BFB and BFB–M.
1275
Elemental analysis (%)a
Hydrogen Nitrogen
65.22 (66.30) 5.90 (5.29) 7.55 (7.36)
53.77 (53.74) 4.63 (4.72) 5.87 (5.96) 11.64 (11.70)
53.51 (53.28) 4.35 (4.68) 5.83 (5.91) 12.36 (12.45)
53.51 (53.31) 4.57 (4.68) 5.74 (5.92) 12.31 (12.40)
57.29 (57.07) 4.00 (4.10) 6.26 (6.33) 14.34 (14.37)
57.09 (56.83) 4.01 (4.08) 6.21 (6.31) 14.64 (14.73)
Compound
abbreviation
Empirical
formula
Yield
(%)
Carbon
Metal
BFB
[C21H20N2O5]n
68
74
71
72
68
72
–
BFB–Mn(II) [MnC21H18N2O5 Á 2H2O]n
BFB–Co(II)
BFB–Ni(II)
BFB–Cu(II)
BFB–Zn(II)
[CoC21H18N2O5 Á 2H2O]n
[NiC21H18N2O5 Á 2H2O]n
[CuC21H18N2O5]n
[ZnC21H18N2O5]n
aObserved value (calculated).
Thermal behavior was determined using a Perkin Elmer (Pyris Diamond) Thermal
Analyzer in nitrogen at 20ꢁC minꢀ1. The solubilities of the polymeric ligand and
polymer metal complexes were determined in both polar and non-polar solvents by the
addition of 2 mg of sample to 10 mL of the solvent kept overnight.
2.4. Synthesis of polymeric ligand
Initially, salicyl alcohol was formed by the addition of bisphenol-A and formaldehyde
in the molar ratio of 1 : 2 (2.28 g, 1.5 mL, respectively) in DMSO. Stirring and heating
on a magnetic stirrer was continued in a three-necked round bottom flask equipped
with a thermometer and a water condenser in the presence of NaOH at 60ꢁC for 2.5 h.
Thereafter, salicyl alcohol of bisphenol-A {4,40propane-2,2-diylbis[(2-hydroxymethyl)-
phenol]} was obtained in good yield.
Barbituric acid (barbH2) (0.01 mol, 1.28 g) was added to the formed salicyl alcohol in
slightly acidic medium and stirred magnetically at 70ꢁC giving a light orange sticky
compound. It was precipitated in distilled water and washed several times with acetone
and diethyl ether, giving an orange powdery material. After drying in an oven for 6–8 h
at 40ꢁC, polymeric ligand (BFB) was obtained. This polymeric ligand lost two protons,
so it can be written as (barb). Anal. Calcd for BFB (%): C, 65.22; H, 5.90; N, 7.55.
Found (%): C, 66.30; H, 5.29; N, 7.36.
2.5. Synthesis of metal polychelates
A series of polymer complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II)
were prepared from BFB in 2 : 1 molar ratio. A typical procedure for preparation of
BFB–Co(II) complex follows:
The polymeric ligand was dissolved in DMSO and heated at 60–70ꢁC in a
three-necked round bottom flask fitted to an ice-cooled condenser. Cobalt(II) acetate
(1.24 g, 0.005 mol) dissolved in DMSO was added to this hot solution and maintained
for 8–10 h at the same temperature. Stirring was continued until complete dissolution
and a royal blue viscous solution was obtained. It was then precipitated with distilled
H2O, filtered and washed several times with distilled H2O and diethyl ether, giving a
dark blue precipitate which was oven dried at 45ꢁC for 5–6 h to obtain the polychelate
BFB–Co(II). Similar procedure was adopted for the preparation of polychelates

1276
N. Nishat et al.
of Mn(II), Ni(II), Cu(II), and Zn(II). The percentage yield of the ligand (BFB) and its
metal polychelates (BFB–M) are listed in table 1.
3. Results and discussion
3.1. Chemistry of polymeric ligand and polymer metal complex
Transition metal polychelate and polymeric ligand were prepared according to the
synthetic route, as shown in scheme 1. The reaction of phenol with formaldehyde is
followed by condensation. Formation of phenoxide is the initial step. Then, formal-
dehyde in its hydrated form gives salicyl alcohol. Condensation of barbituric acid
occurs by the removal of water to form the ligand.
All polychelates including the ligand were colored and insoluble in distilled water,
ethanol, methanol, benzene, and chloroform, but soluble in DMSO and DMF. Their
insolubility indicates their polymeric behavior. Elemental analyses of all the polymers
are in very good agreement with calculated values (table 1). The elemental analysis data
also reveal that ligand-to-metal ratio is 2 : 1.
3.2. FT-IR spectral studies
Barbituric acid has two donors, nitrogen and oxygen, but the metals discussed here
prefer nitrogen [9]. Similarity of FT-IR spectra of the complexes shows binding through
deprotonated nitrogen for all the metals. The absorption at 3422 cmꢀ1 from phenolic–
OH stretching in the polymeric ligand (BFB) is a very broad band which disappears in
the spectra of metal polychelates, suggesting the involvement of hydroxyl oxygen in
bond formation [10]. In the ligand, a band at 1244 cmꢀ1 corresponds to phenolic
(C–OH) group vibration; in metal complexes, these bands shift to lower frequency by
10–14 cmꢀ1, indicating the coordination of metal to oxygen [11]. Sharp signal at
1718–1721 cmꢀ1 is due to C¼O; no change in the frequency of C¼O in the ligand and
metal polychelate shows that the oxygen of barbituric acid is not involved in bond
formation. Aromatic ring has C¼C stretching vibrations at 1654–1620 cmꢀ1
.
The isopropyl group of bisphenol-A shows peaks of almost equal intensity at
1363 cmꢀ1 [12]. The peak at 1458–1452 cmꢀ1 from C–N stretching is a strong evidence
for the polymerization of bisphenol-A–formaldehyde resin with barbituric acid [13]. A
band at 541–530 cmꢀ1 indicates M–N bonding [14] while M–O appears at 618–610 cmꢀ1
[15]. Medium-to-weak intensity bands are due to coordinated water at 952–950 cmꢀ1
(rocking) and 774–770 cmꢀ1 (wagging) in the spectra of Mn(II), Co(II), and Ni(II)
polymer complexes but are not observed in the spectra of Cu(II) and Zn(II)
polychelates. This difference suggests that water is present in Mn(II), Co(II), and
Ni(II) polymer metal complexes.
3.3. NMR spectrum analyses
1H-NMR spectra of BFB and its Zn(II) polychelate were carried out in DMSO at room
temperature using TMS as internal standard (Supplementary material). Dimethyls of

Bisphenol-A–formaldehyde resin
1277
Scheme 1. Proposed synthetic route to polymer metal complexes.
bisphenol-A are between 1.3 and 1.7 ppm in BFB and BFB–Zn(II) [16] while
the resonance signals for the aromatic rings appear as multiplets at 6.6–6.9 ppm [17].
Phenolic OH is at 11.5 ppm [18] for BFB but is absent in the spectrum of BFB–Zn(II),
indicating the coordination of phenolic oxygen. CH2 at ꢀ 4.1 and 4.4 ppm [19] in
the ligand and metal polychelate, respectively, shows the polymerization of
bisphenol-A–formaldehyde unit with barbituric acid.
The 13C-NMR spectra of BFB and its Zn(II) polychelate show carbonyl carbons
(Ca,Cc) at 154.87 and 164.51 ppm, respectively [20]. Methylene of barbituric acid (Cb)

1278
N. Nishat et al.
and formaldehyde (Cd) show peaks at 43.64 and 40.33 ppm, respectively [21]. Aromatic
carbons show multiple overlapping peaks between 39.22 and 39.78 ppm, and at 114.56
and 127.29 ppm. The characteristic peak for the carbon to which hydroxyl is attached
may have shifted to lower frequency after complexation but was not clearly visible in
the spectrum due to several overlapped peaks. Methyl carbon of bisphenol-A (Cg) is
at 31.88 ppm [22].
1
Thus, H-NMR and 13C-NMR spectra reveal that the metal is attached through the
phenolic oxygen of bisphenol-A and nitrogen of barbituric acid.
3.4. UV-Visible analysis
Electronic spectra were recorded in DMSO and various parameters 10 Dq (crystal field
parameter), B (Racah interelectronic repulsion parameter), ꢁ (nephelauxetic ratio) and
ꢁꢁ (covalency parameter) calculated (table 2). The nephelauxetic parameter, ꢁ, is
obtained by using the relation ꢁ ¼ Bcomplex/Bfree ion, where Bfree ion ¼ 960, 1120, and 1080
for Mn(II), Co(II), and Ni(II), respectively.
The magnetic moment of BFB–Mn(II) is 5.72 B.M. corresponding to five unpaired
electrons. The electronic spectrum has three absorptions at 15,562, 19,850, and
24,341 cmꢀ1, assigned to 4T1g(G) 6A1g(F), 4T2g(G) 6A1g(F), and 4Eg(G) 6A1g(F),
respectively. The assignments obtained by fitting the observed spectrum to the
Tanabe–Sugano diagram suggest octahedral geometry [23]. The 10 Dq and B are 4126
and 825 cmꢀ1 while ꢁ and ꢁꢁ values are 0.85 and 0.15, respectively.
The magnetic moment of polymer Co(II) complex was 4.41 B.M. and electronic
transitions at 9632, 14,670, and 18,980 cmꢀ1 correspond to 4T2g 4T1g, 4A2g(P) 4T1g,
4
and T1g(P) 4T1g, respectively. The positions of bands indicate the octahedral
geometry [24]. The value of Dq was calculated from the Orgel energy diagram. The
spectral parameters are 10 Dq ¼ 4694 cmꢀ1, B ¼ 670.6 cmꢀ1, ꢁ ¼ 0.59, and ꢁꢁ ¼ 0.41,
suggesting the covalent nature of the compound.
The magnetic moment of BFB–Ni(II) was 2.62 B.M. Bands at 8942, 16,880, and
3
3
3
21,443 cmꢀ1 correspond to T2g 3A2g, T1g 3A2g, and T1g(P) 3A2g transitions,
respectively, suggesting octahedral complex [25]. Spectral parameters for this
Table 2. Magnetic susceptibility, electronic spectra, and their ligand field parameters.
Magnetic Electronic
moment transitions
a
Abbreviation
BFB–Mn(II)
(ꢂeff
)
(cmꢀ1
)
Assignment
Geometry
"
B
10Dq
ꢁ
ꢁꢁ
5.72
4.41
15,562
19,850
24,341
9632
4T1g(G) 6A1g(F) Octahedral
4T2g(G) 6A1g(F)
11 825 4126 0.85 0.15
13
16
10 670 4694 0.59 0.41
4Eg(G) 6A1g(F)
BFB–Co(II)
BFB–Ni(II)
BFB–Cu(II)
4T2g 4T1g
Octahedral
14,670
18,980
8942
4A2g(P) 4T1g
4T1g(P) 4T1g
3T2g 3A2g
12
14
2.62
1.75
Octahedral
15 794 9530 0.73 0.27
12
16,880
3T1g 3A2g
21,443
14,685
21,872
3T1g(P) 3A2g
2A1g 2B1g(F)
Charge transfer
13
Square planar 14
15
ꢂ
eff, effective magnetic moment in B.M.; "a, dm3 molꢀ1 cmꢀ1
.

Bisphenol-A–formaldehyde resin
1279
polychelate are 10 Dq ¼ 9530.1 cmꢀ1, B ¼ 794.18 cmꢀ1, ꢁ ¼ 0.73, and ꢁ ¼ 0.27, obtained
from the Orgel diagram.
The BFB–Cu(II) has a magnetic moment of 1.75 B.M. and shows bands at 14,685 and
2
21,872 cm 1 assigned to A1g 2B1g and charge transfer indicative of square planar
geometry. The BFB–Zn(II) is diamagnetic and no d–d transitions are observed.
Bfree ion value in the metal complexes is reduced revealing that the complexation
of the metal ion occurs. Thus, the electronic spectral study further supports the
structure proposed for the polymeric ligand and its metal polychelates.
3.5. Thermogravimetric analysis
Degradation was carried out at a heating rate of 20ꢁC minꢀ1 in nitrogen to 850ꢁC.
The weight loss fractions of resin were calculated and the TGA thermograms of BFB
and BFB–M are depicted in the ‘‘Supplementary material’’. The polymers start
decomposing at 100ꢁC with 2–8% weight loss due to the elimination of water/solvent.
For Mn(II), Co(II), and Ni(II) polychelates, the curve showed 10–20% weight loss
corresponding to two coordinated waters in the temperature range of 100–150ꢁC, while
Cu(II) and Zn(II) polychelates do not show weight loss in this temperature range,
indicating the absence of coordinated water and thus favoring four coordinate
geometry for Cu(II) and Zn(II) polychelates. Above 200ꢁC, a gradual mass loss was
observed, but the rate of decomposition was quite rapid between 300ꢁC and 600ꢁC,
which can be attributed to the decomposition of the chelate polymer followed by the
formation of metal oxides (MnO, CoO, NiO, CuO, and ZnO). Greater stabilities of the
polymer metal complexes than the ligand may be attributed to the formation of stable
six-membered rings in all the polymeric complexes. The thermal stability of polymeric
chelates was Cu 4 Ni 4 Zn 4 Co 4 Mn. The greater stability of BFB–Cu(II)
compared with the other polychelates is in agreement with the spectrochemical series,
where Cu(II) complexes are always more stable than other complexes.
3.6. Antimicrobial effects
Antibacterial activities show that the newly synthesized ligand and polymer metal
complexes have biological activity (table 3 and figure 1). Polymer metal complexes of
Cu(II) exhibited the highest activity against both Gram positive and Gram negative
bacteria, the polymeric ligand was inactive to moderately active while other polychelate
complexes were moderately active. Co(II) and Zn(II) polychelates were highly active
against S. aureus but moderately active against E. coli and B. subtilis. Mn(II)
polychelates were highly active against E. coli but moderately active against B. subtilis
and S. aureus. Ni(II) polychelates exhibited high activity against E. coli while moderate
activity against S. aureus. Metal containing polyesters with an antimicrobial activity
have been published [26], and further increasing the biological activity including this
work is still in progress.
The possible mode of biocidal action can be explained with the help of chelation
theory [27, 28]. More activity of the Cu(II) polychelate can be attributed to its higher
stability with N and O donors having strong interaction toward the central metal,
by which its lipophilic nature was increased. The higher activity of Gram positive
bacteria can be explained on the basis that there is a thick outer membrane made up of

1280
N. Nishat et al.
Table 3. Antibacterial analysis (zones of inhibition in mm).
Compounds
B. subtilis
S. aureus
E. coli
BFB
3 ꢂ 2
14 ꢂ 1
12 ꢂ 1
8 ꢂ 2
5 ꢂ 1
16 ꢂ 1
19 ꢂ 2
12 ꢂ 2
16 ꢂ 2
22 ꢂ 3
23 ꢂ 1
4 ꢂ 1
20 ꢂ 2
17 ꢂ 1
21 ꢂ 2
18 ꢂ 3
19 ꢂ 2
25 ꢂ 2
BFB–Mn(II)
BFB–Co(II)
BFB–Ni(II)
BFB–Cu(II)
BFB–Zn(II)
Kanamycin
23 ꢂ 2
6 ꢂ 3
22 ꢂ 1
Figure 1. Antibacterial activity data.
lipopolysaccharide and protein in the Gram negative bacteria which inhibits or partially
permits the penetration of polymer metal complexes into the bacterial cell, but such
membrane is not present in the Gram positive bacteria; instead, a wall of peptidoglycan
is present which easily permits the penetration of polymer metal complexes.
Various other biocidal activities of coordination polymers have been published
[29, 30] with various mechanisms of the inhibition of bacteria. The new polymers
containing metal complexes are not expected to have toxicities to humans; however, a
toxicity study for these polymers should be carried out before their use in vivo. Although
allergies may develop to formaldehyde, in general, this should not be a concern
for formaldehyde-based polymers. As these polymers cause fewer allergic responses
compared with the formaldehyde monomers, however, this issue should also be clarified
before any internal use of these polymers.
4. Conclusions
The new polymeric ligand (BFB) has been synthesized by condensation polymerization
and coordinated with several transition metals. The insolubility of the ligand and metal
complexes indicate their polymeric nature. Cu(II) chelated polymer showed more
antibacterial activity than other polymers. Further work will be done on some of the
polychelates to enhance their properties and make them applicable in biomedical fields.

Bisphenol-A–formaldehyde resin
1281
Acknowledgments
The authors express their sincere thanks to ‘‘The Third World Academy of Sciences
Italy’’ for UV-Vis spectrophotometer EZ-201 (PerkinElmer) through research grant
scheme No. 00-047 RG/CHE/AS.
References
[1] K.C. Gupta, A.K. Sutar. React. Funct. Polym., 68, 12 (2008).
[2] O.E. Woisetschlager, K. Sunkel, W. Weigand, W. Beck. J. Organomet. Chem., 584, 122 (1999).
[3] M.S. Niasari. J. Mol. Catal. A: Chem., 283, 120 (2008).
[4] H.A.A. Medien, A.A. Zahran. Phosphorus, Sulfur Silicon, 178, 1069 (2003).
[5] N.A. Mohamed, A.A. Yassin, Kh.D. Khalil, M.W. Sabaa. Polym. Degrad. Stab., 70, 121 (2000).
[6] V.T. Yilmaz, F. Yilmaz, H. Karakaya, O. Buyukgungor, W.T.A. Harrison. Polyhedron, 25, 2829 (2006).
[7] W.S. Moon, J.C. Kim, K.H. Chung, E.S. Park, M.N. Kim, J.S. Yoon. J. Appl. Polym. Sci., 90, 1797
(2003).
[8] J.J. Merianos, Surface Active Agents. In Disinfection, Sterilization and Preservation, S.S. Block (Ed.),
5th Edn, Lippincott Williams and Wilkins, Philadelphia (2001).
[9] A. Bult, H.B. Klasen. Spectrosc. Lett., 9, 81 (1976).
[10] N. Chantarasiri, T. Damrongkosit, W. Jangwong, D. Sridaeng, S. Suebphan. Eur. Polym. J., 40, 1867
(2004).
[11] S. Saydam, E. Yilmaz. Spectrochim. Acta, Part A, 63, 506 (2006).
[12] R.M. Silverstein, G.C. Bassler, T.C. Morrill. Spectroscopic Identification of Organic Compounds, 5th Edn,
John Wiley and Sons, New York (1991).
[13] A. Chaudhary, R. Saroop, R. Singh. Bol. Soc. Chil. Quim., 47, 203 (2002).
[14] H. Mart. J. Macromol. Sci. Part A: Pure and Appl. Chem., 42, 1197 (2005).
[15] A. Manimaran, R. Prabhakaran, T. Deepa, K. Natarajan, C. Jayabalakrishnan. Appl. Org. Chem., 22,
353 (2008).
[16] C. Soykan, I. Erol, S. Kirbag. J. Appl. Polym. Sci., 90, 3244 (2004).
[17] H. Keypour, S. Salehzadeh, R.V. Parish. Molecules, 7, 140 (2002).
[18] A.W. Nashed, T.A. Elbokl, T.E. Khalil, W. Haase, M.F. Iskander. J. Coord. Chem., 58, 153 (2005).
[19] D. Habibi, V. Izadkhah. Phosphorus, Sulfur Silicon, 179, 1197 (2004).
[20] M. Guzman-Chozas, I.M. Vicario-Romero, R. Guillen-Sans. J. Am. Oil Chem. Soc., 75, 1711 (1998).
[21] E. Mendez, M.F. Cerda, J.S. Gancheff, J. Torres, C. Kremer, J. Castiglioni, M. Kieninger, O.N. Ventura.
J. Phys. Chem. C, 111, 3369 (2007).
[22] D. Casarini, R.K. Harris, A.M. Kenwright. J. Mol. Struct., 355, 121 (1995).
[23] M. John, J. Jose, B. Mathew. J. Appl. Polym. Sci., 92, 272 (2004).
[24] F. Cotton, G. Wilkinson, C. Murillo, M. Bochmann. Advanced Inorganic Chemistry, 6th Edn, Wiley
Interscience, New York (1999).
[25] G.R. Nath, T. Radhakrishnan. Synth. React. Inorg. Met.-Org. Nano Metal Chem., 35, 491 (2005).
[26] N. Nishat, S. Parveen, S. Dhyani, Asma. J. Coord. Chem., 62, 1091 (2009).
[27] Z.S. Chohan, M. Arif, M. Sarfaraz. Appl. Organomet. Chem., 21, 294 (2007).
[28] Z.S. Chohan, M. Arif, M.A. Akhtar, C.T. Supuran. Bioinorg. Chem. Appl., 14, 13 (2006).
[29] L. Yu, Z. Tang, P. Yi, S. Liu, X. Li. J. Coord. Chem., 62, 903 (2009).
[30] A.A. Abu-Hussen, W. Linert. J. Coord. Chem., 62, 1388 (2009).