IR spectroscopic study of the decomposition of dimers of oleic and elaidic acids

Noskov, A. M.; Komlev, A. M.; Вершинин, Е. А.

doi:10.1007/bf01100269

Cited by 3 publications

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“…The absorption band at 1711 cm −1 in both cases can be attributed to stretching vibrations of C=O in one of the types of (cyclic or acyclic) dimer binding observed for the majority of aliphatic carboxylic acids in nonpolar environments [32]. It is also confirmed the absence of the absorption band of the OH group at 3300-3500 cm −1 and the presence of the absorption band at 2677-2688 cm −1 , referring to -OH stretching oleic/undecylenic acids in dimer form in the spectra of OA and UA (see Figure S2, Figure S3, respectively, in Supporting Information File 1) [33]. In the reaction mixture spectra at the end of the first stage of the synthesis, the intensity of the band at 1711 cm −1 is reduced compared to that at the beginning of this stage (spectra S0 Stage1) due to the consumption of acid and formation of a complex with Fe(III).…”

Section: Resultssupporting

confidence: 70%

Two-step single-reactor synthesis of oleic acid- or undecylenic acid-stabilized magnetic nanoparticles by thermal decomposition

Nahorniak¹,

Pasetto²,

Grenèche³

et al. 2023

Beilstein J. Nanotechnol.

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Different iron oxides (i.e., magnetite, maghemite, goethite, wüstite), particularly nanosized particles, show distinct effects on living organisms. Thus, it is of primary importance for their biomedical applications that the morphology and phase-structural state of these materials are investigated. The aim of this work was to obtain magnetic nanoparticles in a single reactor using Fe(III) acetylacetonate as the initial precursor for the synthesis of Fe(III) oleate or Fe(III) undecylate followed by their thermolysis in situ. We proposed a new approach, according to which the essential magnetite precursor (a complex salt of higher acids – Fe(III) alkanoates) is obtained in a solvent with a high boiling point via displacement reaction of acetylacetone with a higher acid from Fe(III) acetylacetonate during its elimination from the reaction mixture under vacuum conditions. Magnetic nanoparticles (NPM) were characterized in terms of morphology, hydrodynamic diameter, and composition via several techniques, such as transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, Fourier-transform infrared spectroscopy/attenuated total reflectance, 57Fe Mössbauer spectroscopy, and X-ray diffraction. The effect of unsaturated oleic (OA) and undecylenic (UA) acids, which are both used as a reagent and as a nanoparticle stabilizer, as well as the influence of their ratio to Fe(III) acetylacetonate on the properties of particles were investigated. Stable dispersions of NPM were obtained in 1-octadecene within the OA or UA ratio from 3.3 mol to 1 mol of acetylacetonate and up to 5.5 mol/mol. Below the mentioned limit, NPM dispersions were colloidally unstable, and at higher ratios no NPM were formed which could be precipitated by an applied magnetic field. Monodisperse nanoparticles of iron oxides were synthesized with a diameter of 8–13 nm and 11–16 nm using OA and UA, respectively. The organic shell that enables the particle to be dispersed in organic media, in the case of oleic acid, covers their inorganic core only with a layer similar to the monomolecular layer, whereas the undecylenic acid forms a thicker layer, which is 65% of the particle mass. The result is a significantly different resistance to oxidation of the nanoparticle inorganic cores. The core of the particles synthesized using oleic acid is composed of more than 90% of maghemite. When undecylenic acid is used for the synthesis, the core is composed of 75% of magnetite.

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Section: Resultssupporting

confidence: 70%

Two-step single-reactor synthesis of oleic acid- or undecylenic acid-stabilized magnetic nanoparticles by thermal decomposition

Nahorniak¹,

Pasetto²,

Grenèche³

et al. 2023

Beilstein J. Nanotechnol.

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“…The peak observed at 2989 cm À1 is associated with the CH 3 stretching vibration whereas the 1709 cm À1 peak is characteristic of the CQO bond of the carboxylic acid. [20][21][22] In addition to the peaks usually associated with oleic acid, a shoulder appears at 1544 cm À1 which may indicate the existence of a carboxylic acid salt. The continuing presence of the 1710 cm À1 band implies that only a proportion is electrostatically bonded as oleate on the PbO surface, and that free oleic acid appears to still be present in the nanocrystal sample.…”

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confidence: 99%

Colloidal synthesis of lead oxide nanocrystals for photovoltaics

et al. 2010

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“…This was also seen here by the intense band at 1708 cm -1 (Figure 4c) for the carbonyl group (C=O), characteristic of the dimer form of oleic acid formed due to hydrogen bonding. However, with the increase in temperature, dimers may change (gradually) into the monomer form (Noskov et al 1980). The carbonyl group of the monomer appears at approximately around 1745 cm -1 Figure 4c).…”

Section: Resultsmentioning

confidence: 99%

Thermal Aging of Bitumen and Biorejuvenator Blends: Triglyceride versus Free Fatty Acids

Santos

Kakar

Partl

et al. 2022

J. Mater. Civ. Eng.

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When added to aged bitumen, oil-based rejuvenators are expected to restore its original properties to some degree. The extent of the rejuvenation depends on the composition of the oils. In this study, the effect of individual components of vegetable oils on blends with bitumen was investigated. 5 and 10 wt% of two free fatty acids, oleic acid and linoleic acid, and one triglyceride, triolein, was blended with bitumen and thereafter the blends underwent thermal aging at high temperatures under air in a ventilated oven. The fatty acids and triglyceride are referred to as rejuvenators in this context. Upon thermal aging, the free fatty acids did not produce any effect or were much less effective in decreasing the complex shear modulus (stiffness) of bitumen as compared with the triglyceride. One reason for this result may be the favorable chemical changes of the triglyceride at high temperatures compared with the free fatty acids. Above all, this study provides basic

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IR spectroscopic study of the decomposition of dimers of oleic and elaidic acids

Cited by 3 publications

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Two-step single-reactor synthesis of oleic acid- or undecylenic acid-stabilized magnetic nanoparticles by thermal decomposition

Two-step single-reactor synthesis of oleic acid- or undecylenic acid-stabilized magnetic nanoparticles by thermal decomposition

Colloidal synthesis of lead oxide nanocrystals for photovoltaics

Thermal Aging of Bitumen and Biorejuvenator Blends: Triglyceride versus Free Fatty Acids

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