Ferric Stearate Research Articles

Permeation of gases through Langmuir-Blodgett films of iron(III) stearate and iron(III) complexes

Ferric stearate and ferric complexes were successfully deposited onto porous support membranes. Langmuir-Blodgett (LB) films of ferric stearate greatly reduced the permeabilities of carbon dioxide and nitrogen through the membrane. Above 65°C, a time-dependent change in the LB film leads to a permeability increase. Permeation through ferric stearate alone was mostly due to a Knudsen diffusion mechanism. LB films selective for carbon dioxide were made by co-depositing poly(2-vinylpyridine) with ferric stearate and with the ferric salt of poly(maleic anhydride 1-octadecene).

Synthesis and characterization of iron stearate compounds

A derivative of a known trinuclear iron(III) stearate cluster was prepared from ferrous sulfate and sodium stearate in ethanol/water solvent with air oxidation. It was also prepared by increasing the pH of a solution of ferrous sulfate stirred with stearic acid. The formula for the trimer as prepared here is [Fe 3O(St) 6(H 2O) 3] +St −(St − = stearate, n-C 17H 35CO 2 −). The reaction of ferric citrate with stearate to form the trimer does not go to completion. The true composition of most iron stearates has not been well established previously. Two iron stearate compounds are available commercially; of these, only “ferrous stearate” appears to be a pure compound, albeit not a simple mononuclear one. The “ferric stearate” of commerce appears to be a mixture of stearic acid and a compound similar to the iron trimer prepared here. References exist to “iron distearate hydroxide” in the literature. The physical and spectroscopic properties of this compound are very similar to those of the iron trimer prepared here. Spectral data (mid- and far-IR, 300 MHz 1H and 75 MHz 13C NMR) and TGA/DSC data are reported for stearic acid, “ferrous stearate,” “ferrie stearate,” and [Fe 3O(St) 6(H 2O) 3][St].

Solid-State Polymerization of Pyrrole within a Langmuir-Blodgett Film of Ferric Stearate

Solid-State Polymerization of Pyrrole within a Langmuir-Blodgett Film of Ferric Stearate

Electrical conduction of polypyrrole in Langmuir-Blodgett films fabricated chemically on ferric stearate substrates

The electrical properties of Langmuir-Blodgett (LB) films of polypyrrole fabricated on a ferric stearate template have been studied. The LB films exhibit a highly organized two-dimensional linear array of polymer granules sandwiched between insulating fatty acid layers. Measured in-plane conductivity is as high as 1.25 S cm −1 whereas conductivity along the film normal is 10 −8 S cm −1, revealing a very high degree of anisotropy. A temperature dependence study suggests charge transport by one-dimensional variable range hopping.

Phase composition of Fe-containing Langmuir-Blodgett layers after thermal treatment in a reactive atmosphere

By the Langmuir-Blodgett technique, mono- and multilayers of ferric stearate were drawn onto silicon wafers. They were thermodesorbed in air at 250–300°C, and the layers formed in this way were found to consist of γ-FeOOH with defective stoichiometry. By heating in H2, the layers can be reduced to Fe2− and even to α-Fe. The latter is magnetically ordered and highly corrosion resistant. Chloride ions, however, induce fast corrosion. FeCl2, formed by this corrosion, is rather unstable and transforms to an Fe3+ phase. The high corrosion resistance of the metallic Fe layer is assumed to be due to its excellent homogeneity. The experiments were performed using XPS, AES, CEMS, and SEM.

Study of the phase composition of iron‐containing Langmuir–Blodgett layers before and after thermal and chemical treatment

AbstractIron‐containing Langmuir–Blodgett mono‐ and multilayers were prepared by depositing ferric stearate onto silicon wafers. Particular care should be taken in order to avoid the presence of alkali ions, which may replace iron ions in the deposited film. By a subsequent heating in air, the fatty acid chains were thermodesorbed. This results in a rather homogeneous coating of the samples by an iron oxide, most probably in the form of crystalline and amorphous γ‐FeOOH, as found by conversion electron Mössbauer, photoelectron and microprobe studies. By a subsequent heating in hydrogen gas or exposure to nascent hydrogen, a partial reduction of the iron oxide layer is possible up to the metallic state (α‐Fe). The Mössbauer spectra show the formation of a mixture of different iron species (Fe3+, Fe2+, Fe0) depending on the reductive treatment.

New developments in the Langmuir-Blodgett manipulation of electroactive polymers

The fabrication of Langmuir-Blodgett (LB) thin films containing electroactive conjugated polymers has been accomplished using a variety of new techniques. In one case, monolayer forming polyion complexes have been formed from acid derivatized conjugated polymers and stearylamine. Alternatively, stable, mixed monolayers containing a surface active processing aid and the emeraldine base form of polyaniline were successfully manipulated into multilayer thin films. Another variation involved the in situ formation of electrically conductive chains of polypyrrole within a preformed multilayer thin film of ferric stearate. The resultant multilayer films exhibited well defined molecular organizations and achieved electrical conductivities in some cases as high as 5 S cm .

Formation, phase composition, and transformations of Langmuir-Blodgett multi- and monolayers containing Fe

Mono- and multilayers of ferric stearate were formed by the Langmuir-Blodgett technique. Thermodesorption of the hydrocarbon chains results in well defined thin oxidic films. Their reduction to Fe2+ and α-Fe was followed by conversion electron Mossbauer spectroscopy. Resonance lines can be observed even if the Fe coverage is less than one monolayer.

Photodegradable high density polyethylene‐based shopping bags— environmental hazard or blessing?

AbstractPlastics are popularly regarded as an environmental hazard. Ferric stearate photoinitiated high density polyethylene (HDPE) films manufactured as supermarket shopping bags were found to rapidly photodegrade after exposure to ultraviolet (UV) and visible light irradiation. Our studies confirmed manufacturer's claims that the bags would degrade more rapidly than standard UV stabilised bags. The photodegradable bags had the potential to completely degrade and be resorbed into the biosphere without adverse effects.

Ultrathin metal films and inorganic clusters via thermodesorption of LB films

AbstractLangmuir‐Blodgett multilayers of cadmium arachidate and ferric stearate were investigated during heating in order to derive information on processes involved in thermodesorption and on the inorganic microstructures left on the substrate after thermodesorption. We studied these processes by X‐ray induced photoelectron spectroscopy (XPS), interference enhanced reflection (IeR), Nomarsky microscopy, electron microprobe analysis and in the case of Fe57‐ions by conversion electron Mössbauer spectroscopy (CEMS).Two different mechanisms of desorption were observed. In the case of cadmium arachidate multilayers it is shown that before desorption the film ruptures laterally and then forms droplets. At temperatures between 250°C and 350°C the aliphatic molecular part is desorbed and the inorganic material (Cd) remains on the surface. These threedimensional Cd‐clusters have a rather uniform lateral distribution and dimension (0.5–2μm) and normal extension larger than 1000Å. The size may be controlled via nucleation and growth kinetics.In contrast to this thermodesorption of the aliphatic chains of ferric stearate multilayers leads to a rather uniform continuous oxidic layer. By means of CEMS it could be shown that during desorption under H2‐atmosphere the iron was reduced (e.g. 40% metallic iron). The degree of oxidation can be controlled via temperature and time of reduction.

CEMS/XPS study of iron stearate Langmuir-Blodgett layers

Langmuir-Blodgett mono- and multilayers of ferric stearate have been formed on oxidized silicon wafers. Thermodesorption of these layers was investigated by conversion electron Mossbauer and photoelectron spectroscopy and some complementary methods. Heating of samples in air up to 523 K leads to a desorption of the fatty acid chains, while the ferric ions are left on the substrate surface. These ions do not cluster laterally like it was found for Cd ions. They form a rather homogeneous, closed oxidic layer. This well defined layer may be used afterwards for further studies of surface reactions as well as interface and intra-layer interactions. The surface iron ions were found to exhibit a reasonably high recoilless fraction. Therefore, Mossbauer spectroscopy allows to follow chemical, structural, and magnetic changes of the iron ions even if the surface is covered by less than one monolayer.

Electron affinity and structure of Langmuir-Blodgett films of cadmium arachidate by means of low-energy electron transmission

The results of low-energy electron transmission experiments on Langmuir-Blodgett (LB) films of cadmium arachidate deposited on copper substrates precoated with ferric stearate are described. The energy location of the bottom of the conduction band ( V 0) for the ordered alkyl tails in the LB film was directly determined to be 0.46±0.02 eV above the vacuum level at −120 to −130°C, that is, the electron affinity ( V A = − V 0) is −0.46±0.02eV. Further, it is demonstrated that the band structure is significantly blurred by the thermal excitation of molecular vibrations and by poor crystallinity. The crystallinity of the films is dependent on the number of layers deposited, and the results are consistent with those obtained by angle-resolved photoemission experiments. The present results strongly suggest that the electron affinities (2.25 and 2.3 eV) obtained by other workers for a metal/monolayer/metal junction, using fatty acid salts, are not those of the ordered parts of the alkyl tails.

Deposition of Langmuir-Blodgett films of ferric stearate

Deposition of Langmuir-Blodgett films of ferric stearate

Protection of styrene-butadiene copolymer film with bound synergistic stabilizers against ferric stearate — catalysed photo-oxidative degradation at elevated temperature

The thermal and photo-oxidative stability at 90°C against 365 nm light in air of commercial styrene-butadiene copolymer (SBR) film in the absence and presence of ferric stearate as an oxidation accelerator was compared with that of SBR in which a synergistic mixture of an antioxidant 3,5-di- t-butyl-4-hydroxybenzylmercaptan (BHBM) in combination with a stabilizer, 1,1,5-triphenyl-2-s-(3′,5′-di- t-butyl-4′-hydroxy) benzyl-iso-4-thiobiuret (PBHBT) bounded with the polymer. The chain-scission and crosslinking reactions were followed by measurement of molecular weight, degree of degradation, gel fraction, elongation-to-break, density, hydroperoxide, carbonyl and hydroxyl groups contents. The newly developed metal-deactivator and photostabilizer PBHBT, has been found to possess a very high efficiency in SBR. It is also shown that the bound PBHBT in combination with BHBM results in improved physical, mechanical and chemical properties of SBR even in the presence of ferric stearate.

Magnetic properties of quasi two-dimensional ferric stearate

Results are given of measurements of magnetic susceptibility, electron spin resonance, and Mössbauer effect of ferric stearate. The stearates have long chain hydrocarbons separating by about 50 Å the planes of metal ions. Thus they are excellent examples of quasi two-dimensional magnetic structures. An interesting sample seems to contain some hydroxy-ferric stearate. In this sample we observed that at high temperatures (295 K≥T≥60 K) the magnetization scaled as H/T, as for superparamagnets. Below 60 K there were deviations from this scaling, shifts in electron spin resonance fields, and splittings of the Mössbauer spectrum, indicating a transition to a state of time-independent magnetic order.

Micronets for electron microscopy

Quantities of grids can be easily and reliably prepared with supporting nets of carbonized Parlodion if just a few principles and procedures are understood and practiced 1. Film nets are best cast on properly prepared, hydrophobic glass slides. Highly consistent results are achieved if slides receive a protracted soaking in a saturated solution of ferric stearate in benzene. Excess then is washed away, presumably leaving little but the adsorbed layer. 2. Nets are most reliably formed by exposing wet films of 0.4–0.6% Parlodion in amyl acetate to steam. 3. The same Parlodion solutions then can be painted on the slides to outline selected areas of nets. This serves the additional purpose of simplifying the floatation of the nets. 4. Grids with dried nets then require baking at 170–180°C to eliminate attenuated films which otherwise span the meshwork. 5. Finally the nets are heavily coated with carbon to achieve stability, and a wetting agent then can be used to render them hydrophilic.

Studies on the Metal-Protein Complex. IV.

In the previous papers the authors obseved that the amount of metal adduct to casein increased with the longer storage days in the system of aqueous solution and oil. It was also found that the rancidity of oil was seriously effected by metal as compared with casein or metal-casein complex.In this paper, authors investigated the relation between the binding ability of inorganic metalfood constituent complexes and the effect of the inorganic metal, food constituents and these complexes on the racidification of oil.Some inorganic metals (copper sulfate, ferric chloride, zinc nitrate) were mixed with non-fat casein, albumin, gluten, soluble starch, and some free fatty acids in soybean oil or aqueous solution. Thus, the amount of adduct formed with these materials and the variation of peroxid value were measured during storage periods.The results obtained were as follows : It was found that the rancidity of oil was seriously effected by metal, starch, unsaturated fatty acids and copper-fatty acid mixture, therefore, the increase of peroxide value was the most highest in the case of copper-fatty acid mixture as compared with free copper and iron-fatty acid mixture system. Namely, it became clear that the easy formation of metal-protein complex and the metalprotein complex thus formed did not promote the rancidity of oil. A correlation existed between the binding ability of inorganic metal-protein complex and rancidity ratios of oil.On the other hand, the marked difference seen between the case of copper-fatty acid mixture and iron-fatty acid mixture systems on the rancidity of oil is not yet clarified. This phenomenon can be considered from only fact that fatty acids reacted with metals (copper and iron). These reaction products were detected as metallic soaps by thin-layer chromatography. It was concluded that the cupric stearate (purchased from Yoneyama Yakuhin Co.) apparently promoted the rancidity of oil, but ferric stearate did not promote the rancidity of oil.

Electron spin resonance study of polyethylene irradiated with ultraviolet light: Effect of addition of ferric stearate

Journal of Polymer Science: Polymer Letters EditionVolume 11, Issue 6 p. 351-355 Article Electron spin resonance study of polyethylene irradiated with ultraviolet light: Effect of addition of ferric stearate Kozo Tsuji, Kozo Tsuji Central Research Laboratory, Sumitomo Chemical Co., Ltd., Takatsuki, Osaka, JapanSearch for more papers by this author Kozo Tsuji, Kozo Tsuji Central Research Laboratory, Sumitomo Chemical Co., Ltd., Takatsuki, Osaka, JapanSearch for more papers by this author First published: June 1973 https://doi.org/10.1002/pol.1973.130110602Citations: 12AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume11, Issue6June 1973Pages 351-355 RelatedInformation

A study of reactions between cupric or ferric sulphate solutions and a stearic acid monolayer

Monomolecular layers have been formed by spreading solutions of stearic acid, copper stearate, ferric stearate, or mixtures of these last on water, 10 −4 M CuSO 4, and 10 −4 M Fe 2(SO 4) 3; the copper and iron contents of the layers were measured over a wide range of pH. An unexpected chemical stability was found in films formed from a mixture of copper and ferric stearates; the metal passed into acid subphase much more slowly than from either stearate alone. Earlier workers' descriptions of the behavior of films formed from stearic acid on Fe 2(SO 4) 3 solution are explained in terms of the iron content, and the important role of Fe (OH 3) is shown. The effect of the colloidal condition of the hydroxide is discussed.

Some New Procedures and Instruments Useful for Microbiological Antibiotic Testing by Diffusion Methods. : IV. Apparatus for a New Method Employing Linear Diffusion into Inoculated Agar-Filled Glass Capillaries

A description of apparatus designed for the routine large-scale assay of antibiotics employing as a basis linear diffusion in glass capillary tubes is presented. The apparatus described includes the glass capillaries, a device for filling large numbers of them simultaneously with seeded agar, a zone reader for the semiautomatic reading of zone lengths, and an assembly suitable for the rapid cleansing of capillary tubes, test tubes, and bottles. The capillaries used were treated with a water-repellent coating such as ferric stearate which caused the agar column to bond more tightly to the glass.