Thermal decomposition process of silver behenate

Article abstract of DOI:10.1016/j.tca.2005.08.030

The thermal decomposition processes of silver behenate have been studied by infrared spectroscopy (IR), X-ray diffraction (XRD), combined thermogravimetry-differential thermal analysis-mass spectrometry (TG-DTA-MS), transmission electron microscopy (TEM) and UV-vis spectroscopy. The TG-DTA and the higher temperature IR and XRD measurements indicated that complicated structural changes took place while heating silver behenate, but there were two distinct thermal transitions. During the first transition at 138 °C, the alkyl chains of silver behenate were transformed from an ordered into a disordered state. During the second transition at about 231 °C, a structural change took place for silver behenate, which was the decomposition of silver behenate. The major products of the thermal decomposition of silver behenate were metallic silver and behenic acid. Upon heating up to 500 °C, the final product of the thermal decomposition was metallic silver. The combined TG-MS analysis showed that the gas products of the thermal decomposition of silver behenate were carbon dioxide, water, hydrogen, acetylene and some small molecule alkenes. TEM and UV-vis spectroscopy were used to investigate the process of the formation and growth of metallic silver nanoparticles.

Full text of DOI:10.1016/j.tca.2005.08.030

Thermochimica Acta 440 (2006) 1–6
Thermal decomposition process of silver behenate
Xianhao Liua,b, Shuxia Luc, Jingchang Zhanga,∗, Weiliang Caoa
a Institute of Modern Catalysis, The Key Laboratory of Science and Technology of Controllable Chemical Reactions of Ministry of Education,
Beijing University of Chemical Technology, Beijing 100029, China
b Institute of Research and Development, China Lucky Film Corp., Hebei Baoding 071054, China
c College of Mathematics and Computer Science, Hebei University, Hebei Baoding 071002, China
Received 15 June 2005; received in revised form 23 August 2005; accepted 26 August 2005
Available online 2 November 2005
Abstract
The thermal decomposition processes of silver behenate have been studied by infrared spectroscopy (IR), X-ray diffraction (XRD), combined
thermogravimetry–differential thermal analysis–mass spectrometry (TG-DTA-MS), transmission electron microscopy (TEM) and UV–vis spec-
troscopy. The TG-DTA and the higher temperature IR and XRD measurements indicated that complicated structural changes took place while
heating silver behenate, but there were two distinct thermal transitions. During the first transition at 138 ◦C, the alkyl chains of silver behenate
were transformed from an ordered into a disordered state. During the second transition at about 231 ◦C, a structural change took place for silver
behenate, which was the decomposition of silver behenate. The major products of the thermal decomposition of silver behenate were metallic silver
and behenic acid. Upon heating up to 500 ◦C, the final product of the thermal decomposition was metallic silver. The combined TG-MS analysis
showed that the gas products of the thermal decomposition of silver behenate were carbon dioxide, water, hydrogen, acetylene and some small
molecule alkenes. TEM and UV–vis spectroscopy were used to investigate the process of the formation and growth of metallic silver nanoparticles.
© 2005 Published by Elsevier B.V.
Keywords: Silver behenate; Combined TG-MS analysis; Thermal analysis; Thermal decomposition process
1. Introduction
ply melt in one step upon heating, but it undergoes a series
of phase transitions before it melts with thermal decomposition
[11,12]. As early as in 1886, Iwig and Hecht reported that silver
butanoate is thermally decomposed into butanoic acid, carbon
dioxide, carbon and metallic silver: 8C3H7COOAg → 8Ag0 +
7C3H7COOH + CO2 + 3C [13]. Griffin et al. reported the ther-
mal decomposition reaction mechanism of silver acetate [14].
The decomposition reaction they proposed is 2CH3COOAg →
2Ag0 + CH3COOH + CO2 + H2 + C. Binnemans et al. [4]
had proposed the decomposition of silver behenate is 2CH3-
(CH2)20COOAg → 2Ag + CO2 + CH3(CH2)20COOH +
CH3(CH2)18CH CH2. The above authors found that the main
decomposition products of the silver alkanoates were metallic
silver and corresponding alkanoic acid, but they were not able
to detect gas products during the thermal decomposition pro-
cess. Although the presence of silver metal and alkanoic acid
can be confirmed by XRD measurement and IR spectroscopy
[15,16], respectively, the reported actual gas products at high
temperatures are only a matter of conjecture.
Silver alkane carboxylate can be considered as inorganic–
organic hybrid materials due to the structure of inorganic layers
(the carboxylate groups and the silver ions) alternating with an
organic layer (the double layers of alkyl chains) [1]. In the last
few years, increasing attention has been paid to the structure
and thermal behavior of silver carboxylates [1–4]. Silver salts
of the long-chain fatty acids are used as the silver source in ther-
mographic and photothermographic materials [5–8]. The most
often used silver fatty acids in thermographic and photothermo-
graphic materials are silver behenate, silver stearate, or a mixture
thereof [5–8].
Silver alkane carboxylate was reported to have a layered
structure [9,10]. The knowledge of the thermal behavior of the
silver carboxylates is of importance for an understanding of
the thermographic process. Silver carboxylate does not sim-
∗
To develop technologically relevant inorganic–organic
hybrid materials, the whole thermal decomposition process must
Corresponding author. Tel.: +86 10 64434904; fax: +86 10 64434898.
E-mail address: zhangjc1@mail.buct.edu.cn (J. Zhang).
0040-6031/$ – see front matter © 2005 Published by Elsevier B.V.
doi:10.1016/j.tca.2005.08.030

2
X. Liu et al. / Thermochimica Acta 440 (2006) 1–6
be known for their applications. In this paper, the detailed ther-
mal behavior and decomposition process of silver behenate have
been investigated by X-ray diffraction (XRD), Fourier transform
infrared spectroscopy (FT-IR) and thermal analysis (TG-DTA).
In order to confirm the species transported in the gas phase at
different temperatures, the thermal decomposition intermediate
gas products of silver behenate will be discussed by the com-
bined TG-MS. Moreover, the thermal formation and growth of
metallic silver nanoparticles will be characterized using TEM
and UV–vis spectroscopy.
ments). The analysis was carried out in helium atmosphere
(100 mL min−1) between 25 and 600 ◦C.
Transmission electron microscopic (TEM) photographs of
metallic silver nanoparticles were taken on a JEM-1200 EX-II
(JEOL) microscope.
The UV–vis spectra of thermally decomposed samples at dif-
ferent temperatures were taken in toluene solvent with a Hitachi
U-3000 spectrophotometer.
3. Results and discussion
2. Experimental
3.1. The thermal behavior and decomposition processes of
silver behenate
2.1. Synthesis
Fig. 1 shows a series of X-ray diffraction patterns of as-
prepared silver behenate at various temperatures, ranging from
25 to 220 ◦C. In the small angle region a set of well-defined
diffraction peaks is observed at 25 ◦C. These diffraction peaks
belong to the (0 0 l) reflections. Such a diffraction pattern is
consistent with a layer structure [4]. Each layer is separated
from the other by twice the length of the alkyl chain [1]. It
is noticeable from Fig. 1 that a well-produced progression of
intense reflections is invariably seen below 140 ◦C. The pres-
ence of progressional reflections up to 120 ◦C indicates that the
bilayer structural motif is sustained [16]. However, heating to
140–160 ◦C leads to substantial decreases of the layer reflec-
tions d(0 0 l) intensities, and the reflections are broadened. It
can also be noticed from Fig. 1 that the XRD peak indexed as
(0 0 l) abruptly decreases at 160 ◦C and cannot be identified at
all at 190 ◦C. Instead, two new peaks are identified at 38.6◦ (2θ)
and 44.3◦ (2θ) when the sample is heated above 190 ◦C. These
peaks can be assigned to (1 1 1) and (2 0 0) reflections of metallic
silver, showing that the major decomposition product of silver
behenate is metallic silver.
All chemicals were purchased from commercial sources and
used as received. The sodium behenate solution was prepared
by firstly dissolving behenic acid in water-tert butyl alcohol
mixing solvent at 80 ◦C, and then 0.25 mol L−1 sodium hydrox-
ide solution was added with stirring at 1500 rpm. The molar
ratio of behenic acid and sodium hydroxide was 1:1. Subse-
quently, the mixture was left being stirred for 1 h at 80 ◦C to
obtain a solution of sodium behenate. Water-tert butyl alcohol
mixed solvent, 5% (w/w) dodecylbenzene sulfonic acid sodium
solution, tributyl phosphate and 3.0 mol L−1 silver nitrate solu-
tion were added with stirring into a reaction vessel. To enhance
monodispersibility of grains and eliminate the formation of
bubbles, dodecylbenzenesulfonicacidsodiumandtributylphos-
phate were added into the preparation process, respectively.
The whole amount of the aforementioned sodium behenate
solution and the equivalent mole amount of 3.0 mol L−1 aque-
ous silver nitrate solution were added at constant flow rates
into the reaction vessel with fast stirring at 30 ◦C. After addi-
tions, the solution was stirred for 40 min at the same tem-
perature and stirring rate. Subsequently, the white precipitate
was filtered, and thoroughly washed with alcohol and distilled
water until electric conductivity of the filtrate became less than
100 ␮S cm−1. Finally, the white silver behenate was dried for
24 h in vacuum. The purity of the silver behenate was checked
by C, H elemental analysis (% calc./found: C 59.05/59.04,
H 9.69/9.67).
2.2. Characterization
The XRD patterns of powder sample were recorded on
a Rigaku D/Max 2500 X-ray diffractometer using Cu K␣1
˚
(1.5406 A) radiation operated at 40 kV and 200 mA for a 2θ
angular range from 3◦ (2θ) to 50◦ (2θ) with a stepsize of 0.02◦
(2θ).
Infrared spectra were measured using a Bruker Vector 22
spectrometer. Pure KBr was used as the background. The pro-
portion of KBr and sample was 1:0.015.
TG-DTA was performed on Pyris Diamond (Perkin-
Elmer). The analyse was conducted in nitrogen atmosphere
(100 mL min−1) between 25 and 600 ◦C. Sample of 10 mg was
put in a Pt cell and heated at a constant rate of 10 ◦C min−1
.
Fig. 1. XRD patterns of silver behenate at different temperatures: (a) 25 ◦C; (b)
100 ◦C; (c) 120 ◦C; (d) 140 ◦C; (e) 160 ◦C; (f) 190 ◦C; (g) 220 ◦C.
MS spectra were measured on ThermostarTM (InProcess Instru-

X. Liu et al. / Thermochimica Acta 440 (2006) 1–6
3
peak at 1416 cm−1 decreases from 25 up to 320 ◦C and shifts
gradually toward lower frequency reaching 1407 cm−1. These
results indicate that the structure change of silver behenate
occurs distinctly above 190 ◦C,◦while the υ(C O) peak at
1716 cm−1 produces around 160 C and the peak at 1700 cm−1
appears at 190 ◦C. In a word, not only the present observation
suggests that a certain structural change takes place, but it is
reasonable to presume that the type of bonding of carboxylate
to silver changes as well. Additionally, the free behenic acid
produced from 190 ◦C has been sustained up to 320 ◦C. It is very
interesting that the alkyl chains assume fully extended all-trans
conformation at higher temperatures [16] and the obtained
metallic silver particles are passivated by behenic acid based
on the analysis of XRD patterns. The IR analysis indicates that
silver behenate is thermal stable below 120 ◦C, above which the
structural change happens. The major products of the thermal
decomposition are metallic silver and behenic acid from190
to 320 ◦C.
TG-DTA curves of as-prepared silver behenate are shown
in Fig. 3. Three intense endothermic peaks at 138, 231, and
318 ◦C are observed. These peakssuggest that structural changes
occurred distinctly around the three temperatures. The peak at
138 ◦C can be assigned to the structural transformation associ-
ated mainly with the disordering of the alkyl chains. The most
intense endothermic peak at 231 ◦C can be attributed to the rapid
thermal decomposition of silver behenate. The broad endother-
mic peak at around 318 ◦C suggests that the thermal decomposi-
tion intermediate products of silver behenate further decompose.
Twoweakendothermicpeaksat159 ◦Cand193 ◦Careobserved.
The endothermic peak at 159 ◦C should be assigned to the crys-
tal phase transition of a mesophase to mesophase transition
[14]. Above 159 ◦C, silver behenate starts to decompose. The
endothermic peak at 193 ◦C should be attributed to the ther-
mal decomposition of silver behenate. The observed exothermic
stages at 460 and 510 ◦C can be rationalized as a result of silver
Fig. 2. Temperature-dependent IR spectra of silver behenate: (a) 25 ◦C; (b)
100 ◦C; (c) 120 ◦C; (d) 140 ◦C; (e) 160 ◦C; (f) 190 ◦C; (g) 220 ◦C; (h) 320 ◦C.
A variable temperature IR measurement is performed in
order to obtain further information on the phase transition of
silver behenate. Fig. 2 presents a series of IR spectra obtained
as a function of temperature for silver behenate. The high-
frequency region from 2800 to 3000 cm−1 reveals the C H
stretching modes of the methyl and the methylene groups of
silver behenate. The two intense bands at 2849 and 2918 cm−1
at 25 ◦C are assigned, respectively, to the symmetric (υs(CH2),
d+) and the antisymmetric (υas(CH2), d−) stretching vibrations
of the methylene groups. The d+ and d− modes usually lie in
the narrow ranges of 2846–2850 cm−1and 2915–2918 cm−1
,
respectively, for all-trans extended chains and in the distinctly
different ranges of 2854–2856 cm−1 and 2924–2928 cm−1
for disordered chains characterized by a significant presence
of gauche conformers [16]. On this basis, the observed peak
frequencies of 2849 and 2918 cm−1 suggest that the alkyl
chains in silver behenate are in an all-trans conformational state
at 25 ◦C. Regarding the d+ and d− modes, the peak positions
in Fig. 2 are invariant from 25 to 140 ◦C. This implies that
the initial all-trans conformational order of the alkyl chains is
preserved up to 140 ◦C. Upon increasing the temperature, the
d+ and d− modes shift toward higher frequencies reaching 2855
and 2923 cm−1, respectively, at 160 ◦C. These results indicate
that a premelting event is characterized by the formation of
gauche conformers. Additionally, silver carboxylate provides
a rare opportunity to observe the effect of temperature on the
headgroup structure. Regarding this matter, it is informative
that the υas(COO−) peak at 1519 cm−1 is rather invariant up
to 120 ◦C and then slightly changes at 140 ◦C and disappears at
190 ◦C. The present observation suggests that the alkyl chains
of silver behenate were transformed from an ordered into a dis-
ordered state around 140 ◦C. On the other hand, the υs(COO−)
Fig. 3. TG-DTA curves of silver behenate.

4
X. Liu et al. / Thermochimica Acta 440 (2006) 1–6
different species, while the thermogravimetric plot shows three
weight losses. Among the three, the first very small one cen-
tred at about 230 ◦C can be attributed mainly to the evolved gas
of carbon dioxide, as confirmed by the following MS analyses.
The m/z value of 44 is characteristic of carbon dioxide which
indicates the carbon dioxide gas product begins to appear at
about 230 ◦C. The m/z values of 18 and 2 are characteristics of
water and hydrogen, respectively. These species at about 260 ◦C
are the second thermal decomposition gas products. From the
analysis of DTG curve, the first and second thermal decomposi-
tion processes are two overlapping stages that dissociate in the
two subsequent processes. The third decomposition gas prod-
ucts appear in the temperature range centred at about 350 ◦C.
The characteristic m/z values of the different species are as
follows: 2(hydrogen), 44(carbon dioxide), 18(water), 26(acety-
lene), 42(propylene), 56(butene), 70(pentene) and 84(hexene).
The mass loss commences at about 230 ◦C in the TG curve
and concludes around 500 ◦C. The actual mass loss amounts
to 75.0% from 230 to 500 ◦C, which is close to that calculated
theoretically (75.8%). The residue from the remaining decom-
position calculates to metallic silver, which agrees with its visual
white appearance. So, it is well confirmed from TG-MS analysis
of silver behenate that the final product of the thermal decom-
position at high temperature (above 500 ◦C) is metallic silver.
3.2. The nature and morphology of silver nanoparticles
Lee et al. [16,17] ascertained from IR spectroscopy that the
silver nanoparticles were passivated by stearates or perfluoro-
carboxylates. In this study, the major solid state products of the
thermal decomposition of silver behenate from 190 to 320 ◦C
are metallic silver and behenic acid. The heated silver behen-
ates were rinsed thoroughly with methanol to remove possible
impurities, and were then dispersed in toluene. Fig. 5 shows
the TEM images and size distribution histograms of the sam-
ples taken after vaporizing the toluene solvent on the surface
of the copper grid. The particle size distribution histograms in
Fig. 5 were measured from an analysis of 350 particles (the
equivalent circular grain diameter of each grain can be deter-
mined). The images reveal that the sizes of the nanoparticles are
quite uniform with an average diameter of 7(2) nm at 190 ◦C and
the size of the silver nanoparticles increases as the temperature
increases. Meanwhile, more and more large silver nanoparticles
with an average diameter of 10(2) nm are formed at 220 ◦C due
to aggregation with increasing the temperature. For growth by
Oswald ripening, aggregation and precipitation lead to a broad
distribution. As a result, it is remarkable that the sizes of silver
nanoparticles are uniform with an average diameter of 18(3) nm
at 320 ◦C. However, more dramatic aggregation is observed as
the heating temperature increases.
Fig. 4. TG-DTG plot and mass analyses of silver behenate.
cluster formation, and their further transformation to the metallic
form.
Fig. 4 presents the TG-MS analysis of silver behenate. In
Table 1 are the detailed characteristic m/z values of the analyzed
Table 1
Selected mass-ions
The formation of silver nanoparticles can be supported by the
results of a UV–vis spectroscopic study. The UV–vis absorption
spectra of the toluene solutions containing silver nanoparticles
for samples formed at three different temperatures are shown in
Fig. 6. For the samples at 190 ◦C and 220 ◦C, narrow absorption
maxima are seen at 425 nm and 450 nm, respectively. In the case
of the sample at 320 ◦C, the absorption maximum is red-shifted
Temperature (◦C)
m/z
Assignment (fragments)
∼230 ◦C
∼260 ◦C
∼350 ◦C
44
2, 18
2, 44, 18, 26, 42,
56, 70, 84
Carbon dioxide
Hydrogen, water
Hydrogen, carbon dioxide,
water, acetylene, propylene,
butene, pentene, hexene

X. Liu et al. / Thermochimica Acta 440 (2006) 1–6
5
Fig. 5. TEM images and size distribution histograms of the obtained silver nanoparticles at different temperatures (a) 190 ◦C; (b) 220 ◦C; (c) 320 ◦C.
to 480 nm. Presumably, this is associated with the increase in the
particle size. Absorption spectra of larger metal colloidal disper-
sions can exhibit broad bands in the UV–vis range due to the
excitation of plasma resonances [18]. In addition, densely aggre-
gation particles exhibit surface plasmon resonance features that
are broadened considerably by dipole–dipole interactions and
can have either red or blue-shifted excitation spectra compared
with those of isolated particles [19].
dioxide, the corresponding acid, and products of the organic
radical reaction were produced upon heating long-chain silver
carboxylates. The organic radicals were supposed to recombine
with the formation of paraffins, or to undergo further reactions.
The obtained products are most likely formed by free radical
pathway by the pyrolysis of silver behenate. In our work, the
thermal decomposition of silver behenate was observed to
occur above 190 ◦C. The C O stretching peak was clearly
identified at ∼1700 cm−1 above 190 ◦C, which must have
arisen from a free acid. Hydrogen atoms required for forming
free acid are provided by the dehydrogenation reaction that may
occur during the thermal decomposition of the organic moiety
of silver behenate. The dehydrogenation of the hydrocarbon
chains has been reported to be the representative reaction of
such materials [21]. During the first transition at ∼230 ◦C, the
3.3. Proposed reaction mechanism of thermal
decomposition of silver behenate
The above results can be discussed by use of the following
reaction mechanism for thermal decomposition of silver behen-
ate. Andreev et al. [20] reported that metallic silver, carbon

6
X. Liu et al. / Thermochimica Acta 440 (2006) 1–6
structural change took place indicating the decomposition of sil-
ver behenate. The major decomposition products were metallic
silver and behenic acid. The combined TG-MS analysis showed
that the intermediate gas products of the thermal decomposition
of silver behenate were carbon dioxide, water, hydrogen, acety-
lene and some small molecule alkenes. The TEM and UV–vis
results indicated that the formation and growth of silver nanopar-
ticles were followed by ablation process due to Oswald ripening
and reached the quite uniform particle distribution. As silver
behenate was continuously heated up to 500 ◦C, the behenic
acid-stabilized silver nanoparticles gradually lost organic moi-
eties due to further thermal decomposition of behenic acid. The
final product of the thermal decomposition was metallic silver.
References
[1] S.J. Lee, S.W. Han, H.J. Choi, K. Kim, Eur. Phys. J. D 16 (2001) 293.
[2] B.B. Bokhonov, L.P. Burleva, D.R. Whitcomb, M.V. Sahyun, Microsc.
Res. Techniq. 42 (1998) 152.
Fig. 6. Optical absorbance of silver nanoparticle/toluene solution of the heated
sample (a) 190 ◦C; (b) 220 ◦C; (c) 320 ◦C.
[3] B.B. Bokhonov, L.P. Burleva, D.R. Whitcomb, M.L. Brostrom, J. Imag-
ing Sci. Technol. 48 (2004) 1.
[4] K. Binnemans, R.V. Deun, B. Thijs, I. Vanwelkenhuysen, I. Geuens,
Chem. Mater. 16 (2004) 2021.
[5] P.J. Cowdery-Corvan, D.R. Whitcomb, Handbook of Imaging Materials,
A.S. Diamond, D.S. Weiss (Eds.), Marcel Dekker, Inc., New York, 2002,
p. 473.
[6] M.R.V. Sahyun, J. Imaging Sci. Technol. 42 (1998) 23.
[7] P.M. Zavlin, A.N. Batrakov, P.Z. Velinzon, S.I. Gaft, L.L. Kuznetsov, J.
Imaging Sci. Technol. 43 (1999) 540.
[8] I. Geuens, I. Vanwelkenhuysen, J. Imaging Sci. Technol. 43 (1999) 521.
[9] F.W. Matthews, G.G. Waren, J.H. Michell, Anal. Chem. 22 (1950) 514.
[10] R. Gilles, U. Keiderling, A. Wiedenmann, J. Appl. Crystallogr. 31 (1998)
957.
[11] N.F. Uvarov, N.F. Burleva, M.B. Mizen, D.R. Whitcomb, C.F. Zou, Solid
State Ionics 107 (1998) 31.
[12] B.B. Bokhonov, L.P. Burleva, D.R. Whitcomb, Y.E. Usanov, J. Imaging
Sci. Technol. 45 (2001) 259.
[13] F. Iwig, O. Hecht, Ber. Dtsch. Chem. Ges. 19 (1886) 238.
[14] R.G. Griffin, J.D. Ellett Jr., M. Mehring, J.G. Bullitt, J.S. Waugh, J.
Chem. Phys. 57 (1972) 2147.
[15] S.J. Lee, S.W. Han, K. Kim, Chem. Commun. (2003) 212.
[16] S.J. Lee, S.W. Han, H.J. Choi, K. Kim, J. Phys. Chem. 106 (2002) 2892.
[17] S.J. Lee, S.W. Han, K. Kim, Chem. Commun. (2002) 442.
[18] P.V. Kamat, M. Flumiani, G.V. Hartland, J. Phys. Chem. B 102 (1998)
3123.
[19] R.P. Van Duyne, J.C. Hulteen, D.A. Treichel, J. Chem. Phys. 99 (1993)
2101.
[20] V.M. Andreev, L.P. Burleva, V.V. Boldyrev, I.Y. Mikhaliv, Izv. SO AN
USSR, Serkhim. Nauk 2 (1983) 58.
TG-MS shows carbon dioxide evolving. The most probable
thermal decomposition scheme for silver behenate may be:
2CH3(CH2)20COOAg → 2Ag + CO2 + CH3(CH2)20COOH
+ CH3(CH2)18CH CH2, which is in accordance to the reaction
pattern proposed by Binnemans et al. As temperature increases,
behenic acids condense to form anhydrides and expel water.
The dehydrogenation of the hydrocarbon chains results in the
formation of hydrogen. The characteristic m/z values at ∼260
and ∼350 ◦C conformed the presence of water and hydrogen,
and the formation of acetylene and some small molecule
alkenes due to the pyrolysis of silver behenate at ∼350 ◦C.
In fact, the thermal decomposition of behenic acid occurs at
∼350 ◦C, and its thermal decomposition gaseous products are
close to that of silver behenate, which are identified by the
TG-MS of pure behenic acid.
4. Conclusions
These results analyzed by infrared spectroscopy (IR), X-
ray diffraction (XRD), thermogravimetry–differential thermal
analysis (TG-DTA) demonstrated that complicated structural
changes took place with heating silver behenate, there were two
distinct transitions. During the first transition at 138 ◦C, the alkyl
chains of silver behenate were transformed from an ordered into
a disordered state. During the second transition at 231 ◦C, a
[21] M.J. Blazso, B. Zelei, E. Jakab, J. Anal. Appl. Pyrol. 35 (1995) 221.