Polyol Compounds Research Articles

Polyols induce acute oxidative stress and mortality in Indian malaria vector Anopheles stephensi (Diptera: Culicidae): potential for use as sugar-cum-toxin source in toxic sugar baits.

Development of insecticide resistance in the major malaria vectors has necessitated the development of novel vector control tools. One such strategy involves the use of toxic sugar baits that targets the sugar-feeding behaviour of mosquito vectors. In this study, we investigated the potential of polyols, as a toxic food (sugar) source in toxic sugar baits against the malaria vector Anopheles stephensi Liston. We examined the acute toxicity of six polyols, namely, erythritol, glycerol, mannitol, propylene glycol (PG), sorbitol, and xylitol on adult female An. stephensi mosquitoes at two different concentrations - 2% and 10%. We also studied changes in fecundity, egg hatchability and mid-gut peroxide levels induced by polyol exposure. Among the six polyol compounds tested, PG was most toxic and lethal followed by glycerol and erythritol (P < 0.001) compared to the control (sucrose). PG induced acute mortality at different tested concentrations. In the erythritol- and glycerol-fed groups, a dose-dependent effect on mortality was observed. Glycerol evidently reduced fecundity and egg-hatchability in gonotrophic cycles G1 and G2. Sucrose was the preferred food source (48%), followed by erythritol (18%), PG (10%) and glycerol (8%). Ingestion of polyols increased peroxide levels in mosquito guts, which persisted for extended durations ultimately resulting in rapid mortality (P < 0.05). The present study highlights the usefulness of sugar polyols for the development of toxic sugar baits with minimal yet effective ingredients. Further research could be focused on field experiments and on the exploration of synergistic effects of different polyols for optimization of field applications. © 2024 Society of Chemical Industry.

Diabetes Mellitus: A Review and Update

Diabetes mellitus is a group of metabolic diseases which are typified by the development of hyperglycaemia which do emanate from defects in insulin secretion, insulin action, or both. The chronic hyperglycaemia of diabetes is associated with long-term damage, dysfunction, and failure of various organs, especially the eyes, kidneys, nerves, heart, and blood vessels. Various types of diabetes mellitus exist which have been discussed in the main part of this article. Many pathogenic processes are involved in the development of diabetes mellitus. These pathogenic processes range from autoimmune destruction of the beta-cells of the pancreas with consequent insulin deficiency to abnormalities which result in resistance to insulin action. The basis of the abnormalities in carbohydrate, fat, and protein metabolism in diabetes is deficient action of insulin on target tissues. Deficient insulin action ensues inadequate insulin secretion and / or diminished tissue responses to insulin at one or more points within the complex pathways of hormone action. Impairment of insulin secretion and defects in insulin action frequently coexist in the same patient, and it is often unclear which abnormality, if either alone, is the primary cause of the hyperglycaemia. The manifestations of marked hyperglycaemia do include: polyuria, polydipsia, weight loss, sometimes with polyphagia, and blurred vision. Impairment of growth and susceptibility to certain infections may also ensue chronic hyperglycaemia. Acute, life-threatening consequences of diabetes mellitus include: hyperglycaemia with ketoacidosis or the nonketotic hyperosmolar syndrome. Long-term complications of diabetes mellitus do include: diabetic retinopathy with potential loss of vision; diabetic nephropathy which leads to kidney (renal) failure; peripheral neuropathy with risk of foot ulcers, amputation, and Charcot joints; as well as autonomic neuropathy which cause gastrointestinal, genitourinary, as well as cardiovascular symptoms and sexual dysfunction. Glycation of tissue proteins and other macromolecules and excess production of polyol compounds from glucose are among the mechanisms that had been postulated to produce tissue damage from chronic hyperglycaemia. Patients who have diabetes mellitus do have an increased incidence of atherosclerotic cardiovascular, peripheral vascular, and cerebrovascular disease. Hypertension, abnormalities of lipoprotein metabolism, and periodontal disease are often found in people who have diabetes mellitus. The emotional and social impact of diabetes mellitus as well as the demands of treatment of diabetes and its complications could cause significant psychosocial dysfunction in patients who have diabetes mellitus as well as their families. Even though there are many types of diabetes mellitus, the vast majority of cases of diabetes mellitus do fall into two broad etiopathogenetic categories which have been extensively discussed in the ensuing article below that has been divided into (a) Overview and (b) miscellaneous narrations. In one category of diabetes mellitus type 1 diabetes mellitus, the cause is an absolute deficiency of insulin secretion. Individuals at increased risk of developing this type of diabetes could often be identified by serological evidence of an autoimmune pathological process that occur within the pancreatic islets and by genetic markers. In the other type of diabetes mellitus, which is the much more prevalent category that is referred to as type 2 diabetes mellitus, the cause of the disease is a combination of resistance to insulin action and an inadequate compensatory insulin secretory response. In the latter category, a degree of hyperglycaemia sufficient to cause pathological and functional changes in various target tissues, but without clinical symptoms, could be present for a long period of time before diabetes mellitus is diagnosed. During this asymptomatic period, it is possible to demonstrate an abnormality in carbohydrate metabolism by measurement of plasma glucose in the fasting state or after a challenge with an oral glucose load. Considering that diabetes mellitus is common as well as the symptoms of diabetes mellitus are non-specific symptoms that may simulate diabetes mellitus, a number of individuals who are afflicted by diabetes mellitus do not know they have diabetes mellitus, there is need for a global educational program on the manifestations and approach that is needed for early diagnosis of the disease so that all clinicians and the entire global population would have a high index of suspicion of the disease. There also a global life style education including regular exercise that would delay onset of or reduce the severity of type 2 diabetes and to improve the quality of life of patients who have diabetes mellitus. It is important to dedicate time to read the article carefully which contains documentations related to the World Health Organization’s global effort to reduce the incidence and severity of diabetes mellitus and all individuals globally should follow carefully recommendations of the World Health organization as well as recommendations of other organizations in the world that have devoted their time to health education on diabetes mellitus. and a number of people

Determination of some physical and mechanical properties of parallel-strand lumber manufactured with bamboo (Phyllostachys bambusoides)

Parallel-strand lumber was manufactured with bamboo (Phyllostachys bambusodies). A polyol compound was added to modify the adhesive (pMDI). Bamboo culms were used to manufacture strands 3 mm thick, 19 mm wide, and 65 cm long. Adhesive was applied to the strands at 200 g/m2 with pressing at 110 °C, 15 kg/cm2, and 30 min. Panels were made with width 600 mm, length 600 mm, and thickness 20 mm. Some physical properties (oven-dry density, air-dry density, moisture content, thickness swelling, and water absorption percentage) and mechanical properties (bending resistance, modulus of elasticity, impact resistance, screw-holding capacity in tangential, radial, and transverse directions) of parallel-strand lumber for both adhesive types were determined. Both resin types improved some physical and mechanical properties of parallel-strand lumber. Additionally, the modulus of rupture and flexural modulus of elasticity of the test specimens using pMDI+5%MP adhesive were higher than those of the test specimens using pMDI. The average screw-holding capacity values of the test specimens were affected by the fiber aspect of the specimens rather than the adhesive type. Parallel-strand lumber produced from both pMDI and pMDI+5%MP adhesives can be used in structural applications, especially in places exposed to the disturbing effects of weather.

Synthesis and Characterization of Novel Non-conjugated hyperbranched polysiloxanes with AIE Effect

To obtain unconjugated hyperbranched polysiloxane (HBPSi), the triethoxyvinylsilane (A-151) and simple polyol compounds were used as raw materials, and two kinds of unconjugated HBPSi which the terminal group is -OH group and C=C bond were synthesized via a simply transesterification condensation, and the factors that affecting their luminescence are also further discussed. The results showed that, both of these two HBPSi exhibits excellent aggregate induced emission effect. The structure rich in π electrons or lone pair electrons in the raw materials basically maintains its original state in the polymer, and the spatial conjugation of the two leads to the luminescence of non-conjugated polymers. A large number of -OH groups in the polymer can form hydrogen bonds, and the promotion of hydrogen bonds makes the target products further gather spontaneously, which further enhances the spatial conjugation and improves the rigidity of the molecules. It can be concluded that under certain conditions, the larger steric hindrance of the molecule itself will affect the polymerization degree of the final product and the aggregation degree of the polymer molecule, while low polymerization and aggregation degree will result in higher energy required for the material to fluoresce. This study provides some reference significance for the preparation of non-conjugated luminescent materials with higher fluorescence intensity.

Oxidation of Monoterpenes to Form Diols and Triols: A Versatile Toolbox for Polymer Synthesis

AbstractPolyols and polyacrylates have a wide range of applications in polymer synthesis as monomers, initiators, or building blocks in a variety of polymerization reaction types. With an ever‐growing need to reduce the global dependency on fossil fuels, finding bio‐based/renewable sources for these compounds is now critical. Herein, the alkene moieties of common, abundant terpenes are functionalized via oxidation to expand the “toolbox” of bio‐based diols and triols. These polyol compounds are readily converted into the corresponding terpene‐derived diacrylates using mild conditions. As a proof of concept, it is demonstrated that these monomers can be used in aza‐Michael polymerizations, forming new (bio)degradable poly‐β‐amino esters.

Molecular mechanism of GylR-mediated regulation of glycerol metabolism in Streptomyces clavuligerus NRRL 3585.

Glycerol is a readily available and low-cost simple polyol compound, which can be used as a carbon source for microorganisms to produce various value-added products. Understanding the underlying regulatory mechanism in glycerol metabolism is critical for making better use of glycerol for diverse applications. In a few reported Streptomyces strains, the glycerol utilization gene cluster (glp operon) was shown to be regulated by the IclR family transcriptional regulator GylR. However, the molecular regulatory mechanism mediated by GylR has not been fully elucidated. In this study, we first analyzed the available Actinobacteria genomes in the NCBI Genome database, and found that the glp operon-like gene clusters are conserved in Streptomyces and several other genera of Actinobacteria. By taking Streptomyces clavuligerus NRRL 3585 as a model system, we identified that GylR represses the expressions of glp operon and gylR by directly binding to their promoter regions. Both glycerol-3-phosphate and dihydroxyacetone phosphate can induce the dissociation of GylR from its binding sequences. Furthermore, we identified a minimal essential operator site (a palindromic 18-bp sequence) of GylR-like regulators in Streptomyces. Our study for the first time reported the binding sequences and effector molecules of GylR-like proteins in Streptomyces. The molecular regulatory mechanism mediated by GylR presumably exists widely in Streptomyces. Our findings would facilitate the design of glycerol utilization pathways for producing valuable products. Moreover, our study provided new basic elements for the development of glycerol-inducible regulatory tools for synthetic biology research in the future.

COMPARING THE GUT METABOLOMIC PROFILES IN HISPANIC AND NON-HISPANIC PEDIATRIC ULCERATIVE COLITIS PATIENTS

Abstract BACKGROUND Diagnosis of ulcerative colitis (UC), a subgroup of inflammatory bowel disease (IBD), is frequently overlooked among the Hispanic population. Although previously thought to impact predominantly white populations, epidemiological studies have shown an increased incidence of UC among Hispanics. Other studies have also noted variations in disease phenotype when comparing Hispanic UC patients to non-Hispanic patients. These variations could be linked to differences in the gut microbiome and shifts in the metabolomic profile. This study aims to compare the profiles of Hispanic UC patients to those of non-Hispanic whites. METHODS Participants aged 7-21 with mild to moderate UC were enrolled at Children’s Hospital of Los Angeles. Eighteen Hispanic and forty non-Hispanic patients were included in this analysis. Metabolite profiling yielded 230 known metabolites. Independent sample T-tests were used to identify significant differences (p&amp;lt;0.05) in metabolites between Hispanic and non-Hispanic UC samples. The average for each metabolite was calculated in Hispanic, non-Hispanic, and healthy patients. Averages were then compared and used to define metabolites as enhanced or diminished. RESULTS 66 metabolites were found to be significantly different between Hispanic and non-Hispanic UC patients. When comparing the profiles of Hispanic to that of non-Hispanic patients, 2 metabolites were enhanced and 64 were diminished. The two enhanced metabolites included 1-monostearin and 1-monopalmitin. Figure 1 depicts the top 10 most diminished metabolites in Hispanic patients compared to non-Hispanic patients. These 10 metabolites were amino acids, amino acid degradation products, and one polyol compound. DISCUSSION This study found a significant difference in the metabolomic profiles of Hispanic UC patients compared to non-Hispanics. This difference could suggest a relationship between ethnicity and the gut’s metabolomic profile. Most notably, Hispanic patients were found to have diminished levels of nearly all significantly different metabolites when compared to non-Hispanic patients. This includes protective fatty acids, amino acids, and amino acid degradation byproducts. Increased deficits of protective anti-inflammatory mediators can be linked to increased risk of severe disease among Hispanic UC patients. These findings support the need for therapeutics targeting specific metabolite deficiencies within Hispanic UC patients.

Efficiency of Osmotic Dehydration of Pomegranate Seeds in Polyols Solutions Using Response Surface Methodology

This study investigates the influence of polyol compounds (sorbitol and erythritol) on the osmotic dehydration process of pomegranate seeds. The efficacy of the osmotic dehydration process was estimated based on the determination of water loss, weight reduction, solid gain, and effective diffusivity and also through a comparison of the results obtained between sucrose and polyol osmotic solutions. Response surface methodology was used to optimize the osmotic process. Quality attributes of pomegranate seeds were determined through the assessment of physical (texture and color) characteristics. This innovative research applies alternative solutions in the osmotic process, which until now, have not been commonly used in the osmotic dehydration of pomegranate seeds processing by researchers worldwide. Results revealed the excellent correlation of experimental values with the model. Erythritol and sorbitol exhibit stronger efficiency than sucrose. However, erythritol was not satisfactory due to the high solid gain. Therefore, the sorbitol osmotic agent seems to be the most suitable for the osmotic dehydration of pomegranate seeds. The optimal condition for maximum water loss (38.61%), weight reduction (37.77%), and effective diffusivity (4.01 × 10−8 m2/s) and minimum solid gain (−0.37%) were 13.03 min, 27.77 °Brix, and 37.7 °C, using a sorbitol solution. Results of texture and color revealed the major impact of erythritol and sorbitol osmotic agents on seed characteristics during the osmotic dehydration process.

Effect of Inoculated Lactic Acid Fermentation on the Fermentable Saccharides and Polyols, Polyphenols and Antioxidant Activity Changes in Wheat Sourdough.

Inoculation of sourdough allows the fermentation medium to be dominated by desired microorganisms, which enables determining the kinetics of the conversion of chemical compounds by individual microorganisms. This knowledge may allow the design of functional food products with health features dedicated to consumers with special needs. The aim of the study was to assess the dynamics of transformations of fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP) compounds from wheat flour as well as their antioxidant activity during inoculated and spontaneous sourdough fermentation. The FODMAP content in grain products was determined by the fructan content with negligible amounts of sugars and polyols. To produce a low-FODMAP cereal product, the fermentation time is essential. The 72 h fermentation time of L. plantarum-inoculated sourdough reduced the FODMAP content by 91%. The sourdough fermentation time of at least 72 h also positively influenced the content of polyphenols and antioxidant activity, regardless of the type of fermentation. The inoculation of both L. plantarum and L. casei contributed to a similar degree to the reduction in FODMAP in sourdough compared to spontaneous fermentation.

Combined Hydrothermal Liquefaction of Polyurethane and Lignocellulosic Biomass for Improved Carbon Recovery

Due to the high versatility of Polyurethane (PUR), its share amongst synthetic polymers to manufacture consumer goods is increasing. This study proposes, tests and validates through pilot processing a highly efficient method for carbon recovery of PUR and in the form of an oil phase concentrated in carbon using hydrothermal liquefaction (HTL). Hot liquid water mixed with PUR residues and a lignocellulosic material (two species of Miscanthus) were treated at subcritical water temperatures, generating an oil-phase rich in hydrocarbons. A high synergistic effect in the co-liquefaction was observed, leading to a carbon and chemical energy recovery to the oil of 71 and 75% respectively. Pilot plant processing, using optimized process parameters, yielded a total process efficiency, accounting heating utilities, of 61%, resulting in a 3.2 ratio of energy return over investment. Using spectroscopic and high-resolution mass spectrometry analysis the oil revealed a high content of nitrogen hetero aromatic and polyol compounds. The high synergy observed for the co-liquefaction of PUR and miscanthus is attributed to recombination of synthetic and biological materials, specifically due to aromatics present in the media and nitrogen-containing compounds recombination. The results show that HTL can be an efficient method for carbon recovery of PUR aided by biomass.

Design of Intelligent Interface Based on Cytocompatible Polymers for Control on Cell Function

Bioinspired polymeric biomaterials with excellent cytocompatibility have been designed in this study. 2-Methacryloyloxyehtyl phosphorylcholine (MPC) is a phospholipid polymer and an essential polymeric biomaterial, which has been used in various biomedical and pharmaceutical applications including implantable medical devices. Furthermore, it is a methacrylate monomer unit and can be copolymerized with other vinyl monomers via conventional radical polymerization. The water-solubility of MPC polymers depends on the molecular composition and molecular weight of the polymers. PMB is a water-soluble polymer copolymerized with hydrophobic n-butyl methacrylate, and can be used as a solubilizing agent for poorly soluble drugs. The phospholipid polymers showed low cytotoxicity, and the solubilized drugs effectively not only penetrated into the cells but also into the surrounding tissues. In addition, the water-soluble MPC polymer containing a phenylboronic acid moiety was observed to spontaneously form polymeric hydrogels with polyol compounds. The reversible polymer hydrogels were used as artificial extracellular matrices for cell immobilization and cell engineering. Polymeric biomaterials with intelligent interfaces might be explored as innovative techniques for application in pharmaceutical and life sciences.

High internal phase emulsion hierarchical porous polymer grafting polyol compounds for boron removal

Removing micro-pollutants is an important global challenge for the development of good adsorbents and environmental engineering issues. In this work, the structure of hierarchically and interconnected porous polymer has been fabricated by a high internal phase emulsion (HIPE) with water-in-oil and used for removing boron from water. This porous polymer was synthesized via monomer radical polymerization and utilized the active sites of monomer –Cl. In this way the vicinal hydroxyl group of N-Methyl-d-glucamine (NMG) was successfully introduced and grafted into HIPE by nucleophilic substitution reaction under the catalysis of triethylamine. The maximum boron uptake capacity was 2.54 mmol/g at a boron concentration of 100 mg/L, and reached adsorption equilibrium after about 2 h. Compared to traditional adsorption membrane materials, the HIPE porous polymer had better mechanical strength and able to resist acid and alkaline in the long-term. Meanwhile the regeneration efficiency of the HIPE30 %-g-PNMG porous polymer remained at 100 % after being used for 10 cycles.

Open-cell polyurethane foams of very low density modified with various palm oil-based bio-polyols in accordance with cleaner production

Abstract Commercially available polyurethane foams are produced mainly from raw materials of petrochemical origin. Vegetable oils have the potential to be inexpensive and widely available resources for the synthesis of polyol compounds. The research presented here describes use of renewable and waste materials for synthesis of open-cell polyurethane foams. This paper discusses the results of studies on the influence of the palm oil’s origin on the properties of bio-polyols. Three oil versions have been chosen: refined, unrefined, as well as used cooking palm oil. A two-stage method based on epoxidation and oxirane ring opening was used to synthesize bio-polyols and these were characterized by hydroxyl values from 150 to 156 mgKOH/g. The open-cell polyurethane foam was synthesized and modified by replacing 20 wt% of petrochemical polyol with bio-polyols synthesized from palm oil. It was found that the modified polyurethane foams comply with requirements for commercial products. The modified foams were characterized by thermal conductivity ranging from 39 to 42 mW/m·K, and apparent densities between ca. 13 and 15 kg/m3. What is more, addition of bio-polyol from unrefined oil and used cooking oil had a beneficial effect on the mechanical strength of the resulting foams. The foams were characterized by more than 95% open-cell content.

A Review of Catalytic Upgrading of Biodiesel Waste Glycerol to Valuable Products

Glycerol is an organic polyol compound, and is an important raw material with extensive applications in daily/petrochemical and pharmaceutical industry. Glycerol is typically obtained by propylene chlorination, while the method used is complicated process and requires high energy consumption. Interestingly, glycerol is recognized as a major by-product of biodiesel production. Approximately 100 kg of glycerol is yielded for 1 tonne of biodiesel production. With the rapid development of the biodiesel industry, glycerol production capacity has been a serious surplus. This review introduces the selective conversion of glycerol into a variety of value-added chemicals such as propylene glycol, propanol, glyceraldehyde, and dihydroxyacetone via selective hydrogenation and oxidation, as well as hydrocarbons and ethers via pyrolysis, gasification and etherification, respectively. The efficiency of different types of catalysts and the influence of reaction parameters on the valorisation of glycerol have been elucidated. Emphasis is also laid on the study of catalytic mechanisms and pathways for some specific reactions.

Site-selective and Stereoselective Syntheses Controlled by the Electron-withdrawing Properties of Cationic Heterocycles

This article describes our stereoselective and site-selective chemical methods for exploiting cationic heterocycles as electron-withdrawing groups (EWGs). We envisioned that the phosphoramide N-H proton of a pyridyl phosphoramide 3 would be activated by the cationic pyridinium moiety that is formed upon protonation. The resulting imide-like N-H proton and the acidic pyridinium proton of the pyridinium phosphoramide 3⋅HX cooperate together, making 3⋅HX a highly acidic dual Brønsted acid. The catalytic ability of 3⋅HX was demonstrated in the development of the first asymmetric Diels-Alder reaction between 1-amide dienes and maleimides. Focusing on the activation of N-bromosuccinimide (NBS) because of its structural similarity to maleimides, the enantioselective bromolactonization of trisubstituted olefinic acids was accomplished utilizing pyridyl phosphoramide 3f as a Brønsted base catalyst bearing an acidic N-H proton. Lastly, our strategy for the site-selective acylation of polyol compounds is described. In our system, a pyridine aldoxime ester 10, used as a mild acylating reagent, was activated by a catalytic amount of Lewis acid via the inductive effect of the cationic pyridinium moiety. The resulting metal complex preferentially attracted the alcohol with a Lewis basic site, thereby facilitating selective acylation via a template effect. This metal-template-driven strategy allowed for the site-selective acylation of diverse α-hydroxyamides, including unprotected N-glycolyl aminosugars.

Tautomeric Study of Schiff Bases Derived from o‐Dihydroxybenzaldehyde by UV‐Vis, IR, 1H NMR, 13C NMR Spectroscopy and Computational Modeling.

AbstractTautomeric equilibria at room temperature were studied for three aromatic imine polyol compounds, previously reported 2‐((2‐hydroxybenzylidene)amino)‐2‐(hydroxymethyl)propane‐1,3‐diol 1 and two new compounds 2‐(((1,3‐dihydroxy‐2‐(hydroxymethyl)propan‐2‐yl)imino)methyl)benzene‐1,4‐diol 2 and 3‐(((1,3‐dihydroxy‐2‐(hydroxymethyl)propan‐2 yl)imino)methyl)benzene‐1,2‐diol 3. The dynamic behavior of these equilibria is described by a combination of IR, UV‐Vis and NMR spectroscopic measurements with DFT and TDDFT calculations in condensed phase. Among the different approaches, the combination of UV‐Vis experimental spectra with the oscillator strengths values estimated from TDDFT calculations allowed for the assessment of the tautomeric populations in DMSO and methanol. These results were consistent with different functionals employed GGA, Hybrid and MetaGGA.

Amdigenol D, a long carbon-chain polyol, isolated from the marine dinoflagellate Amphidinium sp.

A novel polyol compound, amdigenol D, produced by the dinoflagellate Amphidinium sp. has been isolated. Its structure was elucidated by NMR spectroscopy and MS/MS analyses. Amdigenol D consists of a C101-linear carbon backbone including two core structures of amphidinol analogs. Amdigenol D is the longest amdigenol analog identified to date.

Synthesis of Epoxide and Polyol Compounds as Intermediates for Biolubricant from Soybean Oil

Biolubricant derived from vegetable oils is one of alternatives to substitute petroleum based lubricant. The biolubricant is environmental friendly, biodegradable, non toxic and renewable since it is derived from the vegetable oils. Soybean oil is potential as raw material for synthesis epoxide compound as intermediate substances for biolubricant since it has properties of high viscosity, low volatility, thermal stablity, vaporization stability and biodegradable. Polyol compound was produced through hydroxylation process of epoxide compound derived from the vegetable oils. The research aims to synthesize the epoxide compound from soybean oil, polyol compound synthesis from the epoxide compound and to determine kinetic reaction constants of the epoxidation and hydroxylation reactions. The process synthesis of the epoxide compound, as well as, polyol was carried out in a stirred glass reactors equipped with temperature measurement. The epoxidation reaction was carried out at 60 oC, 70 oC, and 80 oC with reaction time of 30 to 180 minutes with 30 minutes interval, while the hydroxylation reaction was carried out at 45 oC, 50 oC, 55 oC, and 60 oC with reaction time of 30 to 120 minutes with 30 minute interval. The highest conversion of soybean oil in epoxidation process was achieved 53.90 % at 70 oC and 120 minutes reaction time. The kinetic reaction constant for epoxidation reaction was achieved kep = 0.0046 min-1 at 70 oC. The highest conversion of hydroxylation process was achieved 91.52 % at 45 oC and 120 minutes reaction time. The kinetic reaction constant for hydroxylation reaction was achieved khd = 0.5528 min-1 at at 45 oC.

Excellent performance of aluminium anode based on dithiothreitol additives for alkaline aluminium/air batteries

For alkaline aluminium/air battery, two original polyol compounds of butantetraol and dithiothreitol are proposed to act as electrolyte additives. It shows that they can retard the self-corrosion of aluminium anode, and enhance its performance effectively. Dithiothreitol has a stronger ability to increase the discharge capacity than butantetraol. The improvement is mainly attributed to the suppression of the side reaction of hydrogen evolution. The formation of the six-membered ring complexes formed by dithiothreitol and aluminium ions is certified by the Fourier transform infrared spectroscopy (FT-IR). The surface morphology and composition of the aluminium anode are characterised by the scanning electron microscope (SEM) and the X-ray photoelectron spectroscopy (XPS) analysis. It shows that dithiothreitol can form a uniform and stable protective layer through dynamic covalent bonds on aluminium anode surface.

Evaluation of application potential of used cooking oils in the synthesis of polyol compounds

According to a new trend related with the circular economy, it is necessary to develop new chemical components based on waste. Used cooking oil (UCO) constitutes an economic and environmental alternative for fresh vegetable oil used in the synthesis of epoxidized oil and polyol. Ten different samples of UCO were collected from local restaurants and their physical and chemical properties were evaluated. The samples were studied by the means of infrared spectroscopy and gel permeation chromatography, and also by determination of the acid, iodine, peroxide, p-anisidine and viscosity values as well as in terms of the presence of polycyclic aromatic hydrocarbons and polychlorinated biphenyls. The UCO samples were characterized by acid values in the range of 1.50–5.21 mgKOH/g and iodine values of 105.7–111.9 gI2/100 g, which is interesting in terms of a potential modification of the oils by the two-step method of epoxidation and oxirane ring opening. Our analysis of the oil properties showed that these materials cannot be reused for food purposes due to oxidative changes confirmed by high peroxide and anisidine values, as well as the presence of polycyclic aromatic hydrocarbons and polychlorinated biphenyls. The most informative indicator describing the susceptibility of oil to oxidation is the parameter TOTOX which in this experiment was in the range 60.5–141.7 for UCOs and 4.7 for the reference oil. However, this research shows that such municipal waste can be used in the synthesis of epoxidized oil and bio-polyol. The properties of the bio-components based on UCO were comparable to the properties of the epoxidized oil and polyols obtained from the fresh rapeseed oil which was used as a reference sample. The epoxy value of the modified UCO was in the range of 0.30-0.33 mol/100 g and for the modified rapeseed oil it was 0.34 mol/100 g. UCO offers potential industrial applications in the field of the synthesis of bio-components for the preparation of polymeric materials.