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Inspired by the phenomenon of superhydrophobic plants and animals in nature, 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX)@copper stearate (CS) core-shell composites with similar properties was prepared. A rough shell layer on the surface of the HMX was observed by scanning electron microscopy (SEM), and a series of in-depth characterization confirmed the successful generation of CS and the core-shell structure of the samples. Differential scanning calorimeter (DSC) proves that the crystal transition temperature (204 °C) and high temperature decomposition exothermal temperature (284 °C) of HMX@CS is almost unchanged compared with pure HMX, which means HMX and CS have good compatibility. Then, the H50 of the samples also increased continuously (16.6 cm→33.7 cm) when the CS shell content increased from 1% to 5%, indicating that the CS shell has a certain buffering performance, and CS will absorb some heat and melt under the stimulation of impact due to its low melting point, which improved impact sensitivity of HMX effectively further. Moreover, HMX@CS has excellent hydrophobic and oleophilic performance, shows excellent wettability with lipid binder, and samples with appropriate CS shell content can continue to combustion stably after covering water. This waterproof and low sensitivity coating provides a new way for the development of multifunctional energetic materials.

The gastric healing and gastric ulcer recurrence preventive effect of Lupeol Stearate (LS) was measured in this study. To evaluate the gastric healing effect, rats were submitted to the 80% acetic acid-induced ulcer model and treated with vehicle (1 ml/kg, p.o.), LS (1 mg/kg, p.o.) or omeprazole (20 mg/kg, p.o.) twice a day for seven days. The gastric injury was evaluated macroscopically, histologically and histochemical; and biochemical parameters were also quantified. To evaluate the effects of LS on gastric ulcer recurrence, mice were ulcerated by gastric instillation of 10% acetic acid and treated with vehicle (1 ml/kg, p.o.), LS (1 mg/kg, p.o.) or ranitidine (20 mg/kg, p.o.) twice a day for ten days. Then, the ulcer recurrence in these animals was induced by IL- 1β (1 µg/kg i.p) at five day after the end of the treatment period. The area of the lesion recurred were measured, as well as the activity of myeloperoxidase and TNF levels. Oral treatment with LS accelerated gastric healing by 63% compared to the group treated with vehicle, which was also evidenced by histological improvement and increased production of mucin in the gastric epithelium. LS elevated the activity of the glutathione S-transferase and reduced the activity of myeloperoxidase, but did not change the levels of reduced glutathione or the activity of superoxide dismutase and catalase at the ulcer site in rats. Regarding the recurrence, the LS treatment reduced the recurred lesions, reducing MPO activity but not TNF levels at ulcer site. It can be concluded that LS promotes the healing of gastric lesions by favoring the mucus production and reducing the migration of neutrophils and that it can reduce the severity of the ulcer recurrence.

Cervical cancer is one of the most common cancers among women, and its mortality rate is increasing rapidly. Drugs such as paclitaxel are used to treat this cancer. Unfortunately, the hydrophobic nature of this drug increases its side effects. Polymeric micro-rods are suitable carriers that can be used to transport hydrophobic drugs such as paclitaxel and release the drug in a slow and controlled manner. The aim of this study is to load paclitaxel onto polymeric inulin stearate micro-rods and evaluate these rods for physicochemical properties, drug release, and cytotoxicity. Inulin was reacted with stearoyl chloride in the presence of 4-dimethylaminopyridine until the inulin stearate was made and lyophilized after purification. Using dialysis method, paclitaxel was loaded onto polymeric micro-rods with two final formulations of 10 and 20%. The prepared rods were studied for surface charge, morphology, loading efficiency, drug release, and the effects of cytotoxicity on HeLa cell line. In water solvent and by dialysis method, inulin stearate interacts with paclitaxel and produces micro-rod with self-assembly approach. SEM images prove the structure of micro-rods. The surface charge of 10% and 20% rods were − 8.19 and − 10.5 mV, respectively. Percentage of drug loading for 10% was 6.33% and for 20% was 14.89%. Finally, evaluation of in vitro drug release showed a sustained and slow release of the drug. Analysis of drug release charts for the two formulations showed that 20% formulation is more suitable for slow drug release studies than 10%. Cytotoxicity results for the 20% formulation also showed that the IC50 value for drug-loaded inulin stearate rods on the HeLa cell line was 3.1 μM. In this study, inulin stearate rods containing paclitaxel (20%) exhibited good in vitro slow-release physicochemical properties.

The study aimed to determine the oil content and identify fatty acid methyl esters such as stearate, palmitate, linolenate, linoleate, and oleate in seeds and nuts like candlenut, peanut, sesame, sunflower, and sacha inchi. Oil extraction was carried out using Soxtec 8000TM and n-hexane solvent. The samples were dried at 50℃. The extraction conditions optimized were temperature 135℃, n-hexane 50 mL, boiling time 40 min, and total extraction time 115 min. Identification of fatty acids was carried out using Attenuated Total Reflection (ATR), Nuclear Magnetic Resonance (NMR), and Gas Chromatography-Flames Ionization Detector (GC-FID). The oil percentage detected in each sample was candlenut (59.95%), peanut (40.08%), sesame (57.06%), sunflower (43.97%), and sacha inchi (51.71). The ATR results show that the flour of nuts and seeds has a strong vibrational frequency of the O−H molecule. Linolenate was detected at a chemical shift of 0.975 ppm in NMR spectra and was found in sacha inchi and candlenut. The ATR, NMR, and GC-FID results showed that all samples contained unsaturated fatty acids. Candlenut, peanut, sesame, and sacha inchi were rich in linoleate (ω-6) as much as 25.68%, 20.15%, 26.38%, and 20.73%, respectively. Oleate was abundant in sesame (21.87%) and sunflower (16.78%). Linolenate was found only in sacha inchi (22.88%). The maximum percentage of stearate was found in sunflower (4.02%) followed by sesame (2.96%), candlenut (1.81%), sacha inchi (1.52%), and peanut (0.71%). This research provides useful information on fatty acid profiles beneficial for health, especially stearic acid, which can substitute trans fatty acids harmful to health.

One of the possible directions of liquid-phase oxidation of α-pinene by atmospheric oxygen leads to the formation of a mixture of terpene oxygen-containing compounds (epoxides, alcohols, ketones, etc.). The problem of this direction is the formation of a large amount of 2,3-epoxypinane which over time turns into trans-sobrerol, campholene aldehyde, trans-pinocarveol, trans-carveol, and trans-3-pinen-2-ol as a result of hydrolysis. One of the abovementioned substances with a solid crystalline structure is trans-sobrerol. Sobrerol is widely used in perfumery for synthesis of synthetically fragrant substances and pharmaceutical industry, in particular, it is a part of medicines with mucolytic action, as well as in the treatment of headaches and diseases such as rhinorrhea and chronic bronchitis. The aim of this work is to identify a crystalline product produced by liquid-phase oxidation of α-pinene with atmospheric oxygen in the presence of cobalt (II) stearate. The process of liquid-phase oxidation was carried out in the following conditions: temperature – 70 °С, air consumption – 16.67 cm3/s, duration – 5 h, amount of catalyst – 0.2–0.5 wt.%. Then the mixture was exposed to steam distillation in order to separate monomers (they contain terpene oxygen-containing compounds and hydrocarbons) from polymers. As a result of settling and storage of the mixture, crystals were found and isolated from the mother liquor solution. Their identification was carried out using IR and 13C NMR spectroscopy as well as scanning electron microscopy. It was found that the spatial organization of the isolated crystals and the standard sample (Sigma Aldrich) is represented by multilayer rectangular plates. Analysis of the IR spectra of the crystals showed that the absorption band at a wave number of 3318 cm–1 corresponds to intramolecular and intermolecular hydrogen bonds in hydroxyl groups, at wave numbers of 2887, 2935,2975 cm–1 it corresponds to methyl groups. The results obtained are comparable with the results of the IR-spectrum of the standard sample. Given the results of previous studies of 1H NMR spectrum [15] and 13C NMR spectrum, it was determined that the resulting crystalline product of liquid-phase oxidation of α-pinene is trans-sobrerol. For citation: Sosnovskaya A.A., Fleisher V.L. Identification of the Crystalline Product of Liquid-Phase Oxidation of α-Pinene with Atmospheric Oxygen in the Presence of Cobalt (II) Stearate. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 4, pp. 173–180. DOI: 10.37482/0536-1036-2021-4-173-180

The present study investigated the active corrosion protection provided by superhydrophobic cerium stearate coatings. Superhydrophobic cerium stearate was deposited on anodized AA2024-T3 at 40 V with different electrodeposition times using a simple DC electrodeposition technique to know the role of electrodeposition time on surface morphology, hydrophobicity, and corrosion resistance. The structure and morphology of cerium stearate was characterized to understand its formation mechanism. Electrodeposition process at 40 V for 120 min resulted in the formation of dual-scale Allium giganteum like micro/nano hierarchical texture of cerium stearate with a water contact angle of 165±1.6°. The cerium stearate coating obtained for 120 min process time had excellent self-cleaning property and good chemical stability, environmental stability, and mechanical durability acceptable for industrial applications. Electrochemical impedance spectroscopy and scanning vibrating electrode technique were used to investigate the active corrosion protection of cerium stearate coating. The electrodeposited cerium stearate coating showed active corrosion protection based on self-healing ability by releasing cerium (Ce3+) ions.

A simple and affordable method for preparing copper-containing tribological nanomaterials by thermolysis of copper(II) stearate at 300°C was developed. The materials produced were studied by X-ray diffraction, atomic force microscopy, and sedimentation analysis. It was shown that the crystallite size does not depend on the thermolysis time. The tribological properties of lubricants with additives of the produced copper-containing nanomaterials (0.025–0.2%) were studied on an end-face friction test machine. At the optimum concentration of nanomaterials (0.05%), the coefficient of friction is the lowest.

Lead zirconate titanate-based piezoelectric ceramics (Pb0·91La0·06(Zr0·58Ti0.42)0.975Nb0·02O3, PLZT) were prepared by water-soluble defatted powder injection molding using bismuth stearate as surfactant. The effects of bismuth stearate surfactant amount on the feed viscosity, water degreasing rate and electrical properties were studied. The results showed that the bismuth stearate coating reduces agglomeration between the PLZT powders and decreases the viscosity of the feed. During sintering, bismuth stearate is decomposed into bismuth oxide, which acts as sintering aid to increase the density of the sintered bismuth stearate-coated PLZT ceramics. Bi3+ dissolves into the perovskite crystal lattice, which increases the tetragonality factor and the content of tetragonal phase, and improves the dielectric, ferroelectric and piezoelectric properties of the bismuth stearate-coated PLZT ceramics. This study provides a novel modification method for the production of injection molded ceramics using a water-soluble binder system.

Made available in DSpace on 2021-06-25T12:16:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-19 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Six lipases were immobilized on a styrene-divinylbenzene support and evaluated on the batch esterification reaction of stearic acid with fusel oil. After a screening design, the two most appropriate lipases were assayed on a packed-bed system, achieving high conversion rates (90-93%) and productivities of isoamyl stearate up to 3144 mmol g(-1) min(-1), which can be used as a substitute to fossil-derived lubricants. Graphic Univ Sao Paulo, Engn Sch Lorena, Lorena, SP, Brazil Sao Paulo State Univ, Sch Pharmaceut Sci, Araraquara, SP, Brazil EARTH Univ, Guacimo, Limon, Costa Rica Univ Fed Rural Rio de Janeiro, Seropedica, RJ, Brazil Univ Fed Alfenas, Inst Chem, Alfenas, MG, Brazil Sao Paulo State Univ, Sch Pharmaceut Sci, Araraquara, SP, Brazil FAPESP: 2016/10636-8 FAPESP: 2020/15513-7 CAPES: 001

By IR spectroscopy and the elemental analysis the composition of the synthesized mixed-ligand complex compound of gadolinium stearate with benzoyltrifluoroacetone (GdSt2BTFA·2H2O) is determined. By optical microscopy and powder X-ray diffraction it is found that the compound is a well-crystallized powder. EPR spectra of the gadolinium stearate powder with benzoyltrifluoroacetone are measured in the range 103-293 K. The zero field splitting parameter is D = 1329.6 MHz. By DFT calculations it is established that the most probable symmetry point group of the synthesized mixed-ligand complex of gadolinium stearate with benzoyltrifluoroacetone is D2d. The Curie temperature θ = 13.52 K and the Curie constant С = 2.42 m3·K/kg are determined and the effective magnetic moment μeff = 7.93 is calculated in the entire temperature range studied for the gadolinium stearate benzoyltrifluoroacetone powder.

The desulphurization process of diesel fuel is carried out to reduce the amount of SO2 emissions that can cause acid rain. However, the desulphurization process in diesel fuel not only removes the sulfur compounds but polyaromatic and polar compounds are also eliminated during this process. The loss of these two compounds can reduce the lubricity properties of diesel fuel. Therefore, it is necessary to add an additive compound that can increase the lubricity properties. In this research, 2-hydroxyethyl ester (HEE) was synthesized as an additive to increase the lubricity of diesel fuel. This compound was synthesized through the transesterification reaction of soybean oil and ethylene glycol with K2CO3 as the base catalyst. The composition of the synthesized additives was analyzed using the Gas Chromatography-Mass Spectrometry (GC-MS). Based on the results of GC-MS spectrum analysis, it is known that the 2-hydroxyethyl ester compound has been formed with a yield of 66.5% (relative to the area of the chromatogram peak). The HEE compound obtained is a mixture of 2 hydroxyethyl palmitate, 2 hydroxyethyl linoleate, 2 hydroxyethyl stearate, 2 hydroxyethyl arachidonate, 2 hydroxyethyl nervate, and 2 hydroxyethyl behenate.

Gadolinium stearate is synthesized in the form of a micropowder. Its composition is determined by elemental and energy dispersive X-ray analyses: [Gd(C17H35COO)3]·(H2O)2.42. The splitting parameters in the zero field (D and E) are determined for the EPR spectrum of the gadolinium stearate powder synthesized at 77 K. The magnetic susceptibility is calculated from the integral intensities of the EPR spectra of the gadolinium stearate powder recorded in a range of 77–293 K. The Curie temperature (θ = 0.16 K) and Weiss constant (С = 7.53 cm3 K mol–1) are determined. The effective magnetic moment is calculated (μeff = 7.8 ± 0.14 μВ), which is constant in the whole temperature range studied for the synthesized gadolinium stearate powder.

Water-mixable oil (WMO) paints are a relatively new addition to the artists’ palette that have increased in usage and popularity over the past few decades. Understanding the composition and properties of WMO paint is essential for the artists who use them and for the people who work with WMO paintings—particularly art conservators. However, the formulations that make WMO paints possible remain undisclosed by paint manufacturers. In this research, fresh paint and naturally-aged paint-outs from Winsor & Newton’s Artisan WMO products were used to study the chemistry of WMO paints. The development of a unique high-pressure liquid chromatography mass spectrometry (HPLC-MS) method enabled the separation and detection of the non-ionic surfactants in the Artisan WMO paints. A data visualization strategy using contour plots was applied for interpretation of results, affording, for the first time, complete structural identifications of surfactant molecules in a WMO paint. The paints were found to contain a complex mixture of ethoxylated molecules, including polyoxyethylene (POE) fatty acid esters derived from the fatty acid mixture of linseed oil. An exudate that formed from the cured paints was also analyzed. More-saturated fatty acid esters, POE oleate and POE stearate, were detected; however, more-reactive POE fatty acid esters were found absent, providing insight relating to the stability of surfactants in the Artisan WMO paints as well as potential curing reactions. HPLC-MS studies were contextualized with physical observations and surface measurements that were performed on the cured samples. Tacky surfaces observed on the cured paint films showed significantly higher surface gloss and surface hydrophilicity; these observations were quantified using glossimetry and droplet contact angle measurements. These results provide insight into the unique chemistry present in WMO paints and provide a basis for future studies for art conservators and conservation scientists working with this new media.

Tacrolimus as an immunosuppressive drug shows poor solubility in aqueous media, accompanied by a low/variable bioavailability in peroral administration due to its high first-pass metabolism. Therefore, in this study, drug-loaded chitosan-coated nanostructured lipid carriers (CCNLCs) were prepared to overcome these limitations. Tacrolimus-loaded NLCs were prepared via solvent displacement technique and were optimized. Stearic acid (SA) and glyceryl mono stearate (GMS) were used as solid lipids, oleic acid (OA) and tween 80 were used as liquid lipid and stabilizer, respectively, in the structure of NLC. The prepared nanoparticles were characterized by size and zeta potential measurements, drug loading determinations, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) analysis. Release profile of tacrolimus from NLCs and CCNLCs was also studied. The results indicated the effect of some preparation parameters on particle size as a dependent parameter. The selected formulations had particle sizes under 100 nm. Conversion of negative zeta potential of NLCs into positive quantities in CCNLCs was attributed to the effect of chitosan coating. SEM images of nanocarriers proved nanoscale dimensions and FTIR analysis showed no unwanted chemical reactions between drug and excipients. NLCs and CCNLCs released the drug in a sustained release pattern. However, chitosan-coating attenuated the burst effect and caused more extended release. The results of this study demonstrated formation of tacrolimus-loaded NLCs and coating them with chitosan with desirable characteristics. These findings suggested that this carrier is a good candidate to overcome serious bioavailability problems of common peroral formulations of tacrolimus.

Thermal reaction process of paraffin/stearate mixtures was studied by thermogravimetric–differential scanning calorimetry–Fourier transform infrared spectroscopy (TG–DSC–FTIR) simultaneous experiments under argon and oxygen atmospheres, and the thermal reaction kinetics were estimated through the non-isothermal measurements and model-free isoconversional methods. The results show that all stearates except for magnesium stearate have a positive effect on the oxidation of paraffin at lower temperature, but only cobalt stearate plays a positive effect during the whole oxidation process; the oxidation of paraffin/cobalt stearate mixture could be divided into three stages, and cobalt stearate could decrease the oxidation reaction temperature of paraffin obviously concerning the first stage; however, the catalytic effects could not be improved markedly by adding more cobalt stearate; the increase in activation energy (Ea) with the increase of cobalt stearate may be attributed to the adsorption catalysis system of the oxidation process.

A heteroligand complex of gadolinium stearate with acetylacetone is synthesized. Its composition is determined via thermogravimetry and energy dispersive analysis. Scanning electron microscopy shows that the synthesized material consists of layered particles with an average size of 50–60 μm. According to data from X-ray phase analysis, the complex of gadolinium stearate with acetylacetone has a tetragonal crystal lattice with parameters a = b = 24.03 A and c = 27.81 A. Diffuse light reflectance spectra of the complex are used to determine its band gap (3.04 eV). The magnetic susceptibility of the complex in the 2 MHz–2.5 GHz range is calculated from the experimentally measured impedances using a vector network analyzer.

This work aims at modeling and characterizing the kinetics of biodegradation of polypropylene loaded with cobalt stearate as pro-oxidant after abiotic treatment. Eight films of these composites were prepared using different pro-oxidant loadings. These films were treated abiotically using accelerated weathering for 40 h, and biotically using aerobic composting as per ASTM D 5338. The experimental data were analyzed using an eight-parameter Komilis model containing a flat lag phase. The model formulations involved hydrolysis of primary solid carbon and its subsequent mineralization. The first step was rate controlling and it included hydrolysis of slowly (Cs), moderately (Cm), and readily (Cr) hydrolyzable carbon fractions in parallel. The model parameters were evaluated by means of nonlinear regression technique. The surface morphology of the films before and after the biodegradability test supported the biodegradation results. The model parameters and undegraded/hydrolyzable/mineralizable carbon evolutions involved moderately and readily hydrolyzable carbons but with the absence of slowly hydrolyzable carbon. These exhibit degradability in the range of 11.20-36.42% in 45 days. Biodegradability increases with progressive increase in pro-oxidant loading. The rate of degradation reaches maximum (0.322-0.897% per day) at around the 39th-12th day. For all the films, readily hydrolyzable carbon fractions and their hydrolysis rate constants (kr) are appreciably increased with increasing pro-oxidant loading. All the films show the presence of growth phase because of their high initial readily hydrolyzable carbon fractions. The SEM images after the abiotic and subsequently biotic treatments were progressively rougher. The methods presented here can be used for the design and control of other similar systems.

Vitamin C (VC)-loaded oleogel (VCOG) with corn oil and monoglyceride stearate was used to replace lipid phase of margarine completely. The oxidative stability of VCOG was evaluated at 60±1°C in a lightproof oven for 18 days and the result showed that VCOG peroxide (6 days) and p-anisidine value (4 days) was significantly lower than that of bulk oil and VC-free oleogel (p0.05). Then, the margarine containing 79.70% VCOG (VCOGM) was in comparison with four commercial butter in sensory and physical characteristic. Results showed that firmness, solid fat content and trans fatty acid of VCOGM were in the lowest values while unsaturated fatty acid and adhesiveness of VCOGM was in the highest values. Furthermore, VCOGM presented the similar springiness, cohesiveness, gumminess, score appearance, texture, taste and overall impression to some/all commercial butters selected in this research (p0.05). These results implied that VC-loaded oleogel was an excellent alternative of lipid phase in margarine which confirmed by 55% "definitely buy" and 25% "try once-then decide".

Nonionic surfactant interfaces are often considered to be unaffected by aqueous ions. However, ions often localize to interfaces and, as such, can interact with surfactants either via direct contact or by affecting interfacial hydrogen bond structures in water. Characterizing these effects is essential to understanding how ions affect interfacial properties at the oil-water interface in the presence of nonionic surfactants. Here, we use two-dimensional infrared (2D IR) spectroscopy in combination with atomistic molecular dynamics (MD) simulations to study the effects of high-concentration Na+ and Ca2+ ions on interfacial hydrogen bond dynamics in heterogeneous sorbitan stearate reverse micelles. Experiments show only minor changes in interfacial hydrogen bond populations when salts are added but those interfacial water network dynamics are slowed by nearly 300%. Molecular dynamics simulations show the slowdown results from an increased disorder in surfactant headgroup orientation and packing density, which stabilizes hydrogen bonding interactions between surfactants and interfacial water.

In this paper, the application of food-grade magnesium stearate microparticles as a stabilizer in the preparation of a novel biocompatible Pickering emulsions was reported. Water-in-oil (W/O) Pickering emulsions were successfully prepared in various solvents such as n-heptane, silicone oil, and food/cooking-grade olive oil, which are all acceptable solvents in the pharmaceutical, cosmetic, and food industries. To the best of our knowledge, there are no available reports on the application of safe and easily available Pickering emulsions prepared using stearate solid particles. It was found that the emulsions could be prepared using mild agitation methods such as shaking by hand, magnetic stirring, and vortex mixing. In contrast, vigorous agitations such as using a homogenizer prevented emulsion formation. It was realized that inorganic salts are a requisite for stable emulsion formations and CaCl2 produced the most stable emulsion. The size of the emulsion was dependent upon the concentration of the microparticle; therefore, its concentration was optimized in this study. The Sauter mean diameter of the emulsions was proportional to agitation speed, which is consistent with those of surfactant-free emulsion systems. We have shown that consistent preparation of emulsions is possible using the novel Pickering emulsion systems in comparison to the conventional surfactant-based emulsion systems. We demonstrated that safe and biocompatible Pickering emulsions can be prepared using easily available food-grade magnesium stearate microparticles without the need for artificial surfactants.

The catalytic performance with high conversion and high selectivity of Ti-based oxide catalysts have been widely investigated. Besides, stability, which is an essential parameter in the industrial process, lacked fundamental understanding. In this work, we combined computational and experimental techniques to provide insight into the deactivation of P25 and TS-1 Ti-based oxide catalysts during the methyl oleate (MO) epoxidation. The considered deactivation mechanisms are fouling and surface oxygen vacancy (OV). The fouling causes temporary catalyst deactivation through active site blockage but can be removed via calcination in air at high temperature. However, in this work, the OV formation plays an important role in the overall performance of the spent catalyst as the deactivated catalyst after regeneration, cannot be restored to the initial activity. Also, the effects of OV in spent catalysts caused (i) the formation of more Ti3+ species on the surface as evident by XPS and Bader charge analysis, (ii) the activity modification of the active region on the catalyst surface as the reduction in energy gap (Eg) occurred from the formation of the interstates observed in the density of states profiles of spent catalyst modeled by the O-vacant P25 and TS-1 models. This reduction in Eg affects directly the strength of Ti–OOH active site and MO bonding, in which high binding energy contributes to a low conversion because the MO needed an O atom from Ti–OOH site to form the methyl-9,10-epoxy stearate. Hence, the deactivation of the Ti-based oxide catalysts is caused not only by the insoluble by-products blocking the active region but also mainly from the OV. Note that the design of reactive and stable Ti-based oxide catalysts for MO epoxidation needed strategies to prevent OV formation that permanently deactivated the active region. Thus, the interrelation and magnitude between fouling and OV formation on catalyst deactivation will be investigated in future works.

Novel three biologically active itaconimido thiourea derivatives (DI, DII and DIII) were synthesized via reaction of N-[4-(isothiocyanatecarbonyl)phenyl] itaconimide with either aniline, p-toluidine or p- amino benzoic acid, respectively. The radical polymerization of DI, DII and DIII in dimethyl sulfoxide using azobisisobutyronitrile initiator was successfully performed to produce three polymers that were denoted as PI, PII and PIII, respectively. Their chemical structures were confirmed by elemental analyses, FTIR, 1H-NMR and mass spectra. They showed a high potency for growth inhibition of E. faecalis, S. epidermidis, E. coli, A. niger, C. neoformans and C. tropicalis. This is not only illustrated by their high inhibition zone diameters but also by their low minimum inhibitory concentrations. Some of them showed activities better than the reference drug Amphotericin B against all the tested fungi. DIII and PIII were safe on normal fibroblast cells of the lungs of the human (MRC-5 cells) through their evaluation using cytotoxic activity measurement. The thermal stability of PVC in the presence of DI–DIII and their polymers PI–PIII was evaluated. In comparison with DBLC, Cd–Ba–Zn stearate and n-OTM as reference stabilizers, DI–DIII and PI–PIII greatly stabilize PVC against thermal degradation. This is evidenced by increased initial decomposition temperatures and decreased weight losses at particular temperatures. It was found that the substituent group having an electron releasing nature that incorporated into DII and PII enhances their performance for PVC stabilization. DI–DIII and PI–PIII achieve a lower degree of discoloration and molecular weight alteration of PVC than the industrial stabilizers.

In this study, the changes in the properties of polypropylene (PP) after loading of modified pro-oxidant were studied. Different proportions of modified-cobalt stearate (CoSt) pro-oxidant were filled in PP, and composites were prepared in a twin-screw extruder through compounding technique. Five films of these composites were prepared using hot press moulding. The modified pro-oxidant loaded PP films were characterized for chemical, physical, thermal, and morphological properties (before and after the biodegradation test). The biodegradability of the modified pro-oxidant loaded PP films was measured according to ASTM D 5338, and the biodegradation intermediate products were evaluated for their eco-toxicological effect. The changes (with respect to PP) in FTIR spectra of modified pro-oxidant loaded PP were noticed before and after accelerated ageing. The tensile properties and thermal stability of modified pro-oxidant loaded PP films decreased as confirmed by universal testing machine (UTM) and thermogravimetric analysis (TGA). Using differential scanning calorimetry (DSC) and XRD analysis, it was found that the percentage crystallinity of modified pro-oxidant loaded PP films has decreased and this led to increased degradability of PP. After the biodegradability test, SEM results of modified pro-oxidant loaded PP films revealed rougher morphology than before the biodegradability test. The highest biodegradability (28.87%) was obtained in PP100T30 film containing 30 phr of modified pro-oxidant. All the eco-toxicity tests of the degraded product materials demonstrated that the degraded products were nontoxic. Hence, the prepared composites can be effectively used as biodegradable flexible packaging materials.