Polyesteramides from linseed oil for protective coatings low acid-value polymers

Linseed and soybean diethanolamides, from the sodium alkoxide-catalyzed reaction of the corresponding oil with diethanolamine, were used as diols to prepare a series of polyesteramides. The diols and dibasic acids or anhydrides were heated in refluxing xylene until the theoretical amount of water was collected in a trap. Low acid-value linseed polymers were prepared with 10, 20, and 30 mole percent excess diol over the dibasic acid, and the effect of the excess diol on molecular weight, viscosity, and film properties of the polymers was examined. Polyesteramides which contained 10 mole percent excess fatty diethanolamide were made with 11 dibasic acids or anhydrides. The polymers were brown-orange oils with Gardner viscosities of Z7 to >>Z10. Number-average molecular weights ranged from 2,200 to 5,200. Data on drying characteristics, hardness, and chemical resistance of films were obtained. The better polymers air-dried rapidly to give hard, glossy films (Sward rocker 20–60). Films baked at 190C for 10 min were softer than the corresponding air-dried films. Xylene resistance of soybean and linseed polymer films was generally excellent, and alkali resistance was moderate. Soybean films showed the better alkali resistance. Presented at Division of Organic Coatings and Plastics Chemistry, 153rd ACS meeting, Miami Beach, Fla., April 1967. No. Utiliz. Res. Dev. Div., ARS, USDA.     

Synthesis of Thumba,Castor and Sal Fatty Ethanolamide-Based Anionic Surfactants

The study involved the preparation and evaluation of anionic surfactants from non-edible oil based thumba (containing unsaturated-rich fatty acids, 80.9 %), castor (containing ricinoleic acid, a hydroxy fatty acid 89.3 %) and sal (containing saturated-rich fatty acids, 56.5 %). The oils extracted from these seeds (using Soxhlet) were reacted with monoethanolamine and diethanolamine to get corresponding fatty mono- and diethanolamides. The ethanolamides were sulfated using chlorosulfonic acid and the sulfated sodium salts were evaluated for surfactant properties namely surface tension, critical micelle concentration (CMC), emulsifying property, wetting, foaming power and calcium tolerance. The properties were compared with sodium dodecyl sulfate (SDS) a well known anionic surfactant. Among the different sulfated sodium salts of ethanolamides, thumba showed superior surfactant properties compared to castor and sal. Sulfated sodium salt of thumba monoethanolamide showed better properties (CMC, 0.035 mmol/L, surface tension 30.2 mN/m and calcium tolerance >1,000 ml, 0.5 % calcium acetate solution) compared to sulfated sodium salts of thumba diethanolamides, followed by sulfated sodium salts of castor monoethanolamide (CMC 0.037 mmol/L, surface tension 35.3 mN/m and calcium tolerance >1,000 ml, 0.5 % calcium acetate solution). Sal being saturated rich was not properly soluble in water and showed poor surfactant properties compared to the other two. Also the sulfated sodium salts of thumba and castor ethanolamides exhibited superior properties compared to SDS.     

Surface-active properties of sodium salts of sulfated fatty acid monoglycerides

Summary Sodium salts of fatty acid monoglyceride sulfates have been prepared by sulfating purified monoglycerides with chlorosulfonic acid or a pyridine-sulfur trioxide complex and subsequent neutralizing. Surface tension, interfacial tension, wetting, suspending and foaming characteristics, calcium stability, and emulsifying property (including stability of the emulsion obtained) of the aqueous solution of these surfactants from C₁₂, C₁₄, C₁₆, and C₁₈ saturated fatty acids and from oleic acid and linoleic acids have been determined and evaluated. With the exception of the wetting characteristic which was found to be optimum in the case of the more hydrophilic products (like those from lauric and linoleic acids) the remaining properties were found to reach a maximum value when the hydrophilic-hydrophobic balance in the surfactant molecule was seemingly optimum, as attained by myristic and oleic acid products.     

Synthesis of diethanolamides of N-lauroyl dipeptides and correlation of their structures with surfactant and antibacterial properties

Diethanolamides (DEA) of proteins possess nonionic skin-compatible, biodegradable, surfactant and antibacterial properties. The DEA of dipeptides are, however, too hydrophilic to be effective surfactants. Hence, DEA of N-lauroyl dipeptides were synthesized and their surfactant and antibacterial properties were correlated with the structures of amino acid moieties. N-Lauroyl condensates of five simple amino acids were coupled with the corresponding amino acid methyl esters and the resulting products were condensed with diethanolamine in the presence of sodium methoxide to yield DEA of N-lauroyl dipeptides. The DEA of N-lauroyl glycine dipeptide showed surfactant properties comparable to lauroyl diethanolamide. The thiol group in the cysteine derivative exerted an unfavorable effect on surfactant properties. The isobutyl side chain in the leucine derivative contributed greatly to the antibacterial activity when compared to the other amino acid derivatives studied. IICT Communication No. 2830.     

脂肪酰胺丙基氧化胺的性能及应用研究

测试了不同碳链的脂肪酰胺丙基氧化胺的去污、润湿、泡沫和乳化性能,考察了其在配方中的增稠及耐寒性能,并与椰油基烷醇酰胺对比。实验结果表明,不同碳链的脂肪酰胺丙基氧化胺的去污力和泡沫力均好于椰油基烷醇酰胺,润湿力则不如椰油基烷醇酰胺,前者在配方中的增稠性能均优于后者,耐寒性能方面,月桂基酰胺丙基氧化胺（LAO）、椰油酰胺丙基氧化胺（CAO）与椰油烷醇酰胺（6501）相近,高碳酰胺丙基氧化胺则要差于椰油基烷醇酰胺。     

A comparative study of the thermal stability and reactions of CH2, CH3 and C2H5 species on the Pd(100) surface

Adsorbed CH₂, CH₂ and C₂H₅ moieties were produced on Pd(100) at 90 K by photoinduced dissociation of the corresponding iodo compounds, and their thermal reactions were established.This laboratory is a part of the Center of Catalysis, Surface and Material Science at the University of Szeged.     

A Mechanistic Study of Sulfur Poisoning of the Water-Gas-Shift Reaction over Pd/Ceria

The effect of sulfur on the water-gas-shift (WGS) activity of Pd/ceria catalysts has been studied using steady-state rate measurements, pulse-reactor studies, and FTIR. After exposing Pd/ceria to SO₂ at 673 K in an oxidizing environment, the WGS rates dropped to a value close to that observed on Pd/alumina. Both pulse-reactor and FTIR measurements showed that cerium sulfates can be readily reduced by CO and re-oxidized by O₂ at 723 K; however, unlike reduced ceria, the Ce₂O₂S formed by reduction of the sulfates cannot be re-oxidized by H₂O or CO₂. The implications of these measurements for understanding the oxygen-storage capacity (OSC) of three-way catalysts are discussed.     

Experimental study on membrane wetting in gas–liquid membrane contacting process for CO2 absorption by single and mixed absorbents

The membrane wetting by the liquid absorbents is an important problem in the operation of gas–liquid membrane contacting process. In order to gain a better understanding on the role of absorbents on membrane wetting, monoethanolamine (MEA, primary amine), diethanolamine (DEA, secondary amine), and 2-amino-2-methyl-1-propanol (AMP, sterically hindred amine) were applied as absorbent solutions. The membrane used for the experiments was the hollow fiber polyvinylidenefluoride (PVDF) membrane. The performance of both single and mixed amine solutions on the CO₂ absorption capacity and membrane wetting potential were investigated. In addition, sodium chloride (NaCl, inorganic salt) and sodium glycinate (SG, organic salt) were added into the MEA aqueous solution to observe CO₂ flux and membrane wetting.The results revealed that the use of MEA solution and SG as absorbents gave highest CO₂ flux. The overall mass transfer coefficients obtained from the experiments also showed the same trend as CO₂ flux, i.e, the values were in the following order: MEA> AMP > DEA. However, the long-term flux was monitored and it was found that MEA also gave lowest flux decline due to the membrane wetting. The use of mixed amine solutions and the addition of NaCl did not help protect the membrane wetting. On the contrary, the addition of SG in to MEA solution can improve flux and resulted in stable CO₂ flux indicating that the membrane wetting was negligible.     

The effects of a potassium overlayer on the reaction pathway of CH2 and C2H5 on Rh(111)

The effect of potassium on the reaction pathways of adsorbed CH₂ and C₂H₅ species on Rh(111) was investigated by means of reflection absorption infrared spectroscopy (RAIRS) and temperature programmed desorption (TDS). Hydrocarbon fragments were produced by thermal and photo-induced dissociation of the corresponding iodo compounds. Potassium adatoms markedly stabilized the adsorbed CH₂ and converted it into C₂H₄, the formation of which was not observed for K-free Rh(111). New routes of the surface reactions of C₂H₅ have been also opened in the presence of potassium, namely its transformation into butane and butene.     

The role of C2 intermediates in Fischer-Tropsch synthesis over ruthenium

The C₂ products formed over Ru during Fischer-Tropsch synthesis often lie well below the Anderson-Schulz-Flory line describing the C₄₊ products. This has led to speculation that either the surface precursor to C₂ hydrocarbons is exceptionally long lived, or that the ethylene formed by CO hydrogenation readsorbs and thereby reenters the chain growth process. In this study, the role of ethylene readsorption on the dynamics of chain initiation and growth is investigated using¹³CO/H₂ and¹²C₂H₄ to differentiate between the carbon sources. Ethylene addition is found to suppress the rate of methanation and increase the rates of formation of C₃₊ hydrocarbons. Ethylene serves as an effective chain initiator, as well as a source of C₁ monomer species which participate in chain propagation. No evidence is seen, though, for the participation of C₂ species in chain propagation.     

Preparation and properties of C60-containing poly(vinyl alcohol)

Poly(vinyl alcohol) (PVA) was reacted with strong base NaH to yield pendant oxy anions, followed with nucleophilic addition to C₆₀. The resulted PVA(C₆₀-Na⁺)_n products were then converted to PVA(C₆₀H)_n by stirring with a strong acid cation exchanger of H⁺-form. Extraction of the C₆₀-containing PVAs by toluene, which is a good solvent for C₆₀, exhibits no color transfer to the toluene phase. The C₆₀-containing PVAs were identified by the characteristic IR and UV-Vis absorptions of C₆₀. The electrochemical behaviors in solution or in film state were investigated by cyclic voltammetric methods. The cyclic voltammogram of 4a shows a reduction peak at −2.30 V which should be due to the bonded C₆₀ chromophores. In the film state, obtained by coating C₆₀-containing PVA solution on graphite electrode, PVA(C₆₀-Na⁺)_n is much easily reduced and oxidized than PVA(C₆₀H)_n. Furthermore, the difference in this reduction and oxidation feasibility is enhanced with increasing C₆₀ content. However, coating with PVA(C₆₀H)_n or PVA(C₆₀-Na⁺)_n reduces the redox ability of the graphite electrode.     

Synthesis of Alkanolamide: a Nonionic Surfactant from the Oil of Gliricidia sepium

Oil of Gliricidia sepium with high contents of C18:2 (32.2 ± 0.3%) and C18:1 (23.8 ± 0.5%) fatty acids was used in the preparation of diethanolamide and epoxidised diethanolamide via transamidation. The epoxidised diethanolamide was synthesized by peroxyformic acid generated in situ by reacting formic acid and hydrogen peroxide with the oil of G. sepium, a renewable resource. The formation of the amide was monitored and confirmed using Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance. The epoxidised diethanolamide showed better surface-active properties than the diethanolamide in terms of emulsion stability, wetting property and foaming power.     

Decomposition and oxidation of CH3 13CH2OH on A12O3, Pd/Al2O3, and PdO/Al2O3 catalysts

Temperature-programmed desorption (TPD) and oxidation (TPO) were used to investigate the decomposition and oxidation of ethanol on Al₂O₃, Pd/Al₂O₃, and PdO/Al₂O₃. Ethyl--¹³C alcohol (CH₃ ¹³CH₂OH) was adsorbed on the catalysts so that reaction pathways of the two carbons could be distinguished. Alumina was mainly a dehydration catalyst, but dehydrogenation was also observed and some carbon remained on the surface. In the presence of O₂, A1₂O₃ oxidized the decomposition products and the-carbon was oxidized faster. Ethanol, which was adsorbed on A1₂O₃, decomposed much faster on Pd/A1₂O₃ by diffusing to Pd and undergoing CO elimination to form CH₄,¹³CO, H₂, and surface carbon. On PdO/A1₂O₃, the decomposition was slower than on Pd/A1₂O₃ until lattice oxygen was extracted above 450 K; the decomposition products were oxidized by lattice oxygen. In the presence of gas phase O₂, Pd/Al₂O₃ was an active oxidation catalyst at low temperature, but lattice oxygen had to be extracted from PdO/A1₂O₃ before it had significant oxidation activity.     

Organometallics derived (Pd + Ln)/SiO2 catalysts for the reactions of synthesis gas conversion

C₃H₆ hydroformylation and CH₃OH synthesis on organometallics derived (Pd + Ln)/ SiO₂ and Pd/SiO₂ catalysts have been studied. The activity and selectivity towards methanol in CO + H₂ reaction were observed to increase for all the modified catalysts while both the hydroformylation activity and selectivity towards oxygenates in C₃H₆ hydroformylation decreased for the catalysts in comparison to those of Pd/SiO₂. The FTIR, TPD data and characteristic catalytic properties of the catalysts studied allow to suggest that C₃H₆ hydroformylation on (Pd + Ln)/SiO₂ catalysts occurs on monometallic Pd clusters without participation of mixed active sites and CO complexes activated thereon.     

Characterization Of C60/Bi2TiO4F2 as a Potential Visible Spectrum Photocatalyst for The Depolymerization of Lignin

Effects of a photocatalyst, C₆₀-modified Bi₂TiO₄F₂, on pine kraft lignin under visible light irradiation were investigated, along with those of Bi₂TiO₄F₂ and C₆₀/TiO₂ as references. The influences of pH, C₆₀ mass fraction, and the initial lignin concentration on lignin conversion and yields of mono-phenolic products were investigated. Seven products were determined by GC/MS, including phenol, 2-methoxyphenol, 4-ethyl-2-methoxyphenol, 2-methoxy-4-vinylphenol, vanillin, acetovanillone, and homovanillic acid. The yields of products and lignin conversion were higher by C₆₀/Bi₂TiO₄F₂ than Bi₂TiO₄F₂ and C₆₀/TiO₂. C₆₀/Bi₂TiO₄F₂ and C₆₀/TiO₂ were more stable than Bi₂TiO₄F₂ upon repetitive recycling of catalyst. The effectiveness of C₆₀/Bi₂TiO₄F₂ declines 25%, whereas that of Bi₂TiO₄F₂ declines 56.4% after being recycled five times. FTIR and HRTEM indicated that the deactivation of photocatalysts might be caused by lignin adsorbed on the surface of photocatalysts and the change in the crystal structure.     

Partial oxidation of ethanol over Pd/CeO2 and Pd/Y2O3 catalysts

The effect of the support nature on the performance of Pd catalysts during partial oxidation of ethanol was studied. H₂, CO₂ and acetaldehyde formation was favored on Pd/CeO₂, whereas CO production was facilitated over Pd/Y₂O₃ catalyst. According to the reaction mechanism, determined by DRIFTS analyses, some reaction pathways are favored depending on the support nature, which can explain the differences observed on products distribution. On Pd/Y₂O₃ catalyst, the production of acetate species was promoted, which explain the higher CO formation, since acetate species can be decomposed to CH₄ and CO at high temperatures. On Pd/CeO₂ catalyst, the acetaldehyde preferentially desorbs and/or decomposes to H₂, CH₄ and CO. The CO formed is further oxidized to CO₂, which seems to be promoted on Pd/CeO₂ catalyst.     

Electrochemical properties of two-component polymers of palladium and pyrrolidine and piperazine derivatives of C60

Redox-active films have been generated via electrochemical reduction in a solution containing palladium(II) acetate and [C₆₀]fullerene, or derivatives of C₆₀. The C₆₀ derivatives include piperazine (piperazine-C₆₀), pyrrolidine (CH₃-pyr-C₆₀), and a pyrrolidine salt, [(CH₃)₂-pyr-C₆₀]⁺ attached to the fullerene unit. In these films, fullerene moieties are covalently bonded to palladium atoms to form a polymeric network. The polymer yields involving the piperazine and pyrrolidine derivatives of C₆₀ are significantly lower than the yield of the C₆₀/Pd film. The CH₃-pyr-C₆₀/Pd and [(CH₃)₂-pyr-C₆₀]⁺/Pd films are electrochemically active in the negative potential region due to the reduction of the fullerene moiety. Reduction of the CH₃-pyr-C₆₀/Pd film is accompanied by the transport of supporting electrolyte cations from the solution into the film. In the first reduction step of the [(CH₃)₂-pyr-C₆₀]⁺/Pd film, both cations and anions of the supporting electrolyte are involved. The piperazine-C₆₀/Pd film exhibits electrochemical activity at both negative and positive potentials. In the negative potential region, reduction of the fullerene cage takes place. Oxidation of the piperazine moiety is responsible for the observed current in the positive potential range. Here, the oxidation process of this polymer is significantly influenced by the presence of metallic palladium particles in the film.     

Characteristics and Catalytic Properties of Pd/SiO2 Synthesized by One-step Flame Spray Pyrolysis in Liquid-phase Hydrogenation of 1-Heptyne

In this study, Pd/SiO₂ catalysts with 0.5–10 wt.% Pd loadings were prepared by one-step flame spray pyrolysis (FSP) and characterized by N₂ physisorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), CO chemisorption, and X-ray photoelectron spectroscopy (XPS). The average cluster/particles size of Pd as revealed by TEM were ca. 0.5–3 nm. The turnover frequencies (TOFs) of the flame-made catalysts decreased from 66.2 to 4.3 per s as Pd loading increased from 0.5 to 10 wt.%, suggesting that the catalytic activity was dependent on Pd particle/cluster size. However, there were no appreciable influences on 1-heptene selectivity. The flame-made Pd/SiO₂ showed better properties than the conventional prepared catalysts. Their advantages are not only the presence of large pores that facilitates diffusion of the reactants and products, but also the high-catalytic activity of as-synthesized catalysts so that further pretreatment is not necessary.     

Studies on kinetics and preparation of C36 dimer acid esters

C₃₆ Dimer acids were esterified with various short-chain alcohols, namely 2-propanol, n-butanol, n-hexanol, n-octanol, 2-octanol and 2-ethyl-1-hexanol by using sulfuric acid as catalyst and benzene as an azeotropic solvent. Various reaction parameters were standardized. In case of isopropyl esters, acid-to-alcohol mole ratio of 1:5 and sulfuric acid concentration of 2% based on the weight of dimer acids were found to be optimum. In case of straight-chain primary alcohols, namely n-butanol, n-hexanol and n-octanol, 1:2.5 mole ratio of acid to alcohol and 1% by weight of sulfuric acid were found satisfactory. Esterification reaction rates were determined from the fall in acid value of the product. The reaction followed pseudo first order kinetics. The reaction rates increased with the increase in chainlength of straight-chain primary alcohols from n-butanol to n-octanol. The rate of reaction decreased from n-octanol to 2-ethyl-1-hexanol to 2-octanol due to the branching of the chain in 2-ethyl-1-hexanol and secondary nature of the −OH group in 2-octanol.     

Preparation and antibacterial activity of C2-benzaldehyde-C6-aniline double Schiff base derivatives of chitosan

C₂-benzaldehyde-C₆-aniline double Schiff base derivatives of chitosan were synthesized with positioning protection method for the first time. The structures and properties of the new synthesized products were characterized by Fourier transform infrared spectroscopy, ¹³C nuclear magnetic resonance, scanning electron microscope image, X-ray diffraction, and elemental analysis. The elemental analysis results indicated that the degrees of substitution of the products were from 39.6% to 48.2%. The synthesized compounds exhibited an excellent solubility in organic solvents. The antibacterial activities of all of the derivatives were tested in the experiment, and the results showed that the prepared chitosan derivatives had significantly improved antibacterial activity of chitosan and C₂-benzaldehyde Schiff bases of chitosan toward Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 35218). Antibacterial activity of the Schiff bases against E. coli differs from the substituent at the same position of different anilines and increases as the sequence aniline?>?p-toluidine?>?o-toluidine, and the antibacterial activity of the Schiff bases against S. aureus increases as the sequence p-toluidine?>?aniline?>?o-toluidine. The I_C50 of the C₂-benzaldehyde-C₆-aniline double Schiff base derivatives of chitosan against E. coli and S. aureus is 0.0035 and 0.0031?mg?L^?1, respectively, much lower than that of chitosan (0.0064?mg?L^?1) and C₂-benzaldehyde Schiff bases of chitosan (0.0054?mg?L^?1). The cytotoxicity test showed that compared with chitosan and C₂-benzaldehyde Schiff bases of chitosan, the prepared chitosan derivatives had lower cytotoxicity against SCG-7901. This paper provided a new method for the synthesis of Schiff bases of chitosan, which was enlightening.