Synthesis and optimization ring opening of monoepoxide linoleic acid using p-toluenesulfonic acid

Biolubricant base oils, 9,12-hydroxy-10,13-oleioxy-12-octadecanoic acid (HYOOA) was synthesized based on the esterification reaction of Monoepoxide linoleic acid 9(12)-10(13)-monoepoxy 12(9)-octadecanoic acid (MEOA) with oleic acid (OA) and catalyzed by p-Toluenesulfonic acid. The optimum conditions for the experiment using D-optimal design to obtain high yield% of 84.61, conversion% of 83.54 and lowest OOC% of 0.05 were predicted at OA/MEOA ratio of 0.2:1 (mol/mol), PTSA/MEOA ratio of 0.4:1 (mol/mol), reaction temperature at 110°C, and reaction time at 4.5 h. The FTIR peaks of HYOOA indicate the disappearance of the absorption band at 820 cm(−1), which belongs to the oxirane ring. (13)C and (1)H NMR spectra analyses confirmed the result of HYOOA with appearance carbon-ester (C = O) chemical shift at 174.1 ppm and at 4.06 ppm for (13)C and (1)H NMR respectively

Synthesis and Applications of Organotin (IV) Compounds: Mini Review

Organotin (IV) compounds have seen a marked increase in industry utilization over the years and exhibited enormous economic benefits as well as environmental costs due to their numerous industrial, medical, and agricultural uses and other applications. The present review is a continuation of a series of reviews on the use of organotin (IV), chemicals, synthesis, characteristics and geometry as well as the industrial and biological applications

Synthesis and characterization of bubble wrap-like hollow barium silicate–carbonate nanospheres for the epoxidation of styrene

Novel porous bubble wrap-like hollow barium silicate–carbonate nanospheres were successfully prepared at a barium/CTAB molar ratio of 0.75 and 1.00. The average pore size, BET surface area and total pore volume of the most catalytically active catalyst in the epoxidation of styrene, 1.00BaMST were 5.0 nm, 42 m2 g−1 and 0.0771 cm3 g−1, respectively. The styrene epoxidation reaction was carried out using H2O2 as an oxidant. Barium silicate and carbonate groups detected on the catalyst’s surface are proposed to activate the H2O2 and selectively oxidize the styrene to styrene oxide. The 1.00BaMST achieved 63.3% of styrene conversion and 77.8% of epoxide selectivity at mild conditions (3 h, 60 ◦C). The reaction energy barrier was calculated to be 17.3 kJ mol−1

Fabrication and Characterization of Nickel Chloride Doped PMMA Films

Films of PMMA and PMMA doped with NiCl2 with different contents were prepared using the casting technique. The optical properties of all films were investigated using spectrophotometric measurements of absorbance and transmittance in the wavelength range 200–800 nm. The change of the calculated values of the optical energy gaps with increasing NiCl2 content has been interpreted in terms of the structural modifications of the PMMA matrix. The optical energy gap decreased from 3.6 to 3.05 eV with increasing the NiCl2 concentration to 0.4%. The effect of doping on the optical constants of films such as refractive index, extinction coefficient, real and imaginary parts of dielectric constant, optical conductivity, and skin depth has been reported. All these constants were increased with increasing NiCl2 concentration with the exception of skin depth which is different result

Effect of Nano ZnO on the Optical Properties of Poly(vinyl chloride) Films

Optical properties of pure and doped poly(vinyl chloride) (PVC) films, prepared by using casting technique, with different nanosize zinc oxide (ZnO) concentrations (1-20) wt% have been studied. Parameters such as extinction coefficient, refractive index, real and imaginary parts, Urbach energy, optical conductivity, infinitely high frequency dielectric constant, and average refractive index were studied by using the absorbance and transmittance measurement from computerized UV-visible spectrophotometer (Shimadzu UV-1601 PC) in the spectral range 200-800 nm. This study reveals that the optical properties of PVC are affected by the doping of ZnO where the absorption increases and transmission decreases as ZnO concentration increases. The extinction coefficient, refractive index, real and imaginary parts, infinitely high frequency dielectric constant, and average refractive index values were found to increase with increasing impurity percentage. The Urbach energy values are found to be decreasing with increasing ZnO concentration. The optical conductivity increased with photon energy after being doped and with the increase of ZnO concentration

Effect of Nano ZnO on the Optical Properties of Poly(vinyl chloride) Films

Optical properties of pure and doped poly(vinyl chloride) (PVC) films, prepared by using casting technique, with different nanosize zinc oxide (ZnO) concentrations (1–20) wt% have been studied. Parameters such as extinction coefficient, refractive index, real and imaginary parts, Urbach energy, optical conductivity, infinitely high frequency dielectric constant, and average refractive index were studied by using the absorbance and transmittance measurement from computerized UV-visible spectrophotometer (Shimadzu UV-1601 PC) in the spectral range 200–800 nm. This study reveals that the optical properties of PVC are affected by the doping of ZnO where the absorption increases and transmission decreases as ZnO concentration increases. The extinction coefficient, refractive index, real and imaginary parts, infinitely high frequency dielectric constant, and average refractive index values were found to increase with increasing impurity percentage. The Urbach energy values are found to be decreasing with increasing ZnO concentration. The optical conductivity increased with photon energy after being doped and with the increase of ZnO concentration

Palladium nanoparticles supported on fluorine-doped tin oxide as an efficient heterogeneous catalyst for Suzuki coupling and 4-nitrophenol reduction

Immobilization of palladium nanoparticles onto the fluorine-doped tin oxide (FTO) as support Pd/FTO, resulted in a highly active heterogeneous catalyst for Suzuki-Miyaura cross-coupling reactions and 4-nitrophenol reduction. The Pd/FTO catalyst has been synthesized by immobilization of palladium nanoparticles onto FTO via a simple impregnation method. ICP-MS analysis confirmed that there is 0.11 mmol/g of palladium was loaded successfully on FTO support. The crystallinity, morphologies, compositions and surface properties of Pd/FTO were fully characterized by various techniques. It was further examined for its catalytic activity and robustness in Suzuki coupling reaction with different aryl halides and solvents. The yields obtained from Suzuki coupling reactions were basically over 80%. The prepared catalyst was also tested on mild reaction such as reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). Pd/FTO catalyst exhibited high catalytic activity towards 4-NP reduction with a rate constant of 1.776 min(-1) and turnover frequency (TOF) value of 29.1 hr(-1). The findings revealed that Pd/FTO also maintained its high stability for five consecutive runs in Suzuki reactions and 4-NP reductions. The catalyst showed excellent catalytic activities by using a small amount of Pd/FTO for the Suzuki coupling reaction and 4-NP reduction

Spectroscopic and photochemical stability of polystyrene films in the presence of metal complexes

Five metal complexes containing Ni(II), Cu(II), Zn(II), Cd(II) and Sn (II) metals and 4-amino-5-(pyridine-4-yl)-4H-1,2,4-triazole-3-thiol have been prepared for use as polystyrene photostabilizers. The additives (0.5% by weight) were mixed with polystyrene in chloroform to produce modified PS using the casting method. PS films were irradiated (λ = 250â380 nm) with a light absorption intensity of 6.02 Ã 10â9 ein dmâ3 sâ1 at room temperature. The photostabilization activity of the films was determined by monitoring various changes, such as the carbonyl index, hydroxyl index, weight loss, viscosity average molecular weight, surface morphology and quantum yield of the chain scission. Keywords: Polystyrene films, Metal complexes, Photostabilization, 4-Amino-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiole, Quantum yiel

Date Palm Seed Extract for Mild Steel Corrosion Prevention in HCl Medium

The inhibition effects of the date palm seed extract corrosion of mild steel in 0.5 M HCl at different concentrations are investigated by potentiodynamic polarisation (PDP), electrochemical impedance spectroscopy (EIS) and weight loss tests. Additionally, this study provides a fundamental understanding of aromatic adsorption on iron (Fe) surfaces. Furthermore, the surface morphology and the extracts are performed using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The maximum inhibition efficiency of 95, 96, and 91% were realised at 1400 mg/L for PDP, EIS, and weight loss, respectively. The inhibitive action of the DPS extract against mild steel corrosion in an acid solution has been supported by SEM analysis. The FTIR showed that the extract contained hydroxyl (−OH) and methoxyl (−OCH3) functional groups. The DFT depicted the adsorption sites at the oxygen (O) and carbon (C) atoms as deduced from the Fukui functions, Mulliken atomic charge, and the highest occupied molecular orbital-lowest occupied molecular orbital (HOMO-LUMO) analysis. The DPS preferred to form chemical bonds by donating electrons to the Fe surface. The coordinate bonds between the O and C atoms and the metal surface resulted in a high inhibition efficiency value. In conclusion, date palm seed extract is an effective inhibitor to protect mild steel from corrosion in an acidic medium