Butyl Glycol Research Articles

Effect of Food-Simulating Liquids on the Leachability of Plasticizers from Dental Tissue Conditioners.

Tissue conditioners are composed of poly(ethyl methacrylate) (PEMA) powder and plasticizer/ethanol mix liquid. Butyl phthalyl butyl glycolate (BPBG) plasticizer is commonly used in tissue conditioners, but the main concern with phthalate plasticizer is its leachability and biocompatibility, especially the estrogenic activity and cytotoxicity of phthalate. Therefore, acetyl tributyl citrate (ATBC) plasticizer has been introduced and formulated as plasticizer in tissue conditioner; however its leachability characteristics are still unknown. Furthermore, the effect of foodsimulating liquids toward leachability of BPBG and ATBC plasticizers has not been documented. The objective of this study was to compare the effect of food-simulating liquids on the leachability of plasticizers and hardness of two experimental tissue conditioners containing BPBG and ATBC plasticizers. Ten experimental materials were prepared using PEMA polymer powder with 95% plasticizer (BPBG and ATBC) and 5% ethanol by volume, using powder to liquid ratio of 1.67:1, and the thickness was controlled at 3 mm. Shore A hardness value was measured after immersion in distilled water, artificial saliva, 25% ethanol/water mix, 3% citric acid, and coconut oil at 37°C. Measurements were taken at 2 hours and 1, 2, 3, 4, 7, 10, 14, 21, 28, 42, 56, and 84 days. Six readings were taken for each sample and hardness change was calculated and statistically analyzed using Wilcoxon signed-rank test. Increase in hardness value was noted for both plasticizers over time with the highest increase was when immersed in coconut oil. Shore A hardness value was significantly higher in ATBC after 84 days of immersion in all food-simulating liquids. The increase in hardness is due to plasticizer/ethanol leaching; however, as ethanol content was the same (5%), the hardness change is attributed to the leaching of plasticizers. Leaching of both plasticizers was highest in coconut oil indicating that tissue conditioners may have a shorter intraoral lifetime in patients eating high-fat diet.

Effects of Adding Waste Oil Ethylene Glycol Butyl Ether to Diesel Fuel

This study focuses on the improvement of fuel properties of waste frying oils and their direct use without chemical processing. For this purpose, 10% filtered waste frying oil was added to the diesel fuel. Afterwards, the test fuels were formed by adding 5%, 10% and 20% volumes of Di Ethylene Butyl Glycol Ether to this mixture. The obtained fuel mixtures were run in a diesel engine at a con-stant engine speed of 3000 rpm at 20%, 40%, 60% and 80% engine loads, and the changes in engine fuel consumption, exhaust gas temperature and ego emissions were investigated. The results showed that all the goose emissions increased with the direct use of waste oil, but the exhaust emissions decreased with the addition of Di Ethylene Butyl Glycol Ether. With the addition of Di Ethylene Butyl Glycol Ether, the viscosity and density values decreased and the heating value in-creased. The best fuel mixture was obtained with DAGD20 mixture with 20% Di Ethylene Butyl Glycol Ether added. In this fuel mixture, BSFC decreased, Ex-haust Gas Temperature increased, NOx increased, CO increased, CO2 decreased, HC increased, and smoke decreased.

Synergistic Effect of Frequently Found Ions in the Flotation of Pb-Zn Sulfide Ores on Air/Water Interface

The aqueous ions influence the properties of air bubbles and, therefore, the recovery of flotation. This study aims to reveal the synergistic effect of frequently found ions in the flotation of Pb-Zn sulfide ores. In this context, dynamic surface tension measurements, bubble coalescence time, Sauter mean diameter (SMD), bubble size distribution (BSD), and dynamic foam stability (DFS) measurements were carried out using artificial process waters (APWs). APW with the minimum ion concentration is expressed as “APW1” with the ionic strength (I) of 0.03 mol/dm3. The concentration of the ions in APW1 was increased by 3, 5, and 10 times, and thus APW3 (I = 0.08 mol/dm3), APW5 (I = 0.13 mol/dm3), and APW10 (I = 0.26 mol/dm3) were prepared, respectively. The results of this study indicated that the surface tension increased slightly in the presence of APW related to the ion concentration. Potassium ethyl xanthate (KEX) at high concentrations was effective in the reduction of surface tension. As the APW concentration increased, finer bubbles were obtained with a narrower size range. The stability of the foam increased with butyl glycol (BG) and APW concentration. There was no need to use a frother (BG) for the flotation experiments in the presence of APW1 or APWs with higher ionic strength.

Experimental investigation to elucidate the hydrate Anti-Agglomerating characteristics of 2-Butoxyethanol

To alleviate the severity of hydrate formation in subsea oil and gas pipelines, the injection of anti-agglomerants (AAs) is one of the promising approaches. In this work, we investigate the hydrate anti-agglomerating characteristics of 2-butoxyethanol, also called butyl glycol ether (BGE), which has been reported in the literature as an effective synergist for kinetic hydrate inhibitors (KHIs), and a solvent for low dosage hydrate inhibitors (LDHIs). In view of its hydrophobic and hydrophilic moieties, we evaluate the adsorption affinity of BGE for the oil–water interface employing the interfacial tensiometer (IFT) apparatus. Moreover, a micromechanical force (MMF) apparatus was used to probe the interfacial behavior of hydrate particles, wherein we measured the cohesive forces between cyclopentane hydrate particles in the presence of BGE at atmospheric pressure and 274.2 K. The kinetics of methane hydrate formation and resistance-to-flow were assessed while measuring the dynamic pressure–temperature data and motor torque signals alongside with visual observations, respectively, employing a high-pressure visual autoclave (HPVA). IFT results reveal the strong surface active properties of BGE with a substantial reduction in oil–water interfacial tension at ambient conditions. However, no considerable change in the cohesive forces between cyclopentane hydrate particles was observed through MMF measurements. In contrast, HPVA results reveal that the addition of BGE enhanced the kinetics of methane hydrate formation; however, the corresponding torque pattern/visual interpretations indicated an anti-agglomerating action of BGE. While synergistically combining the BGE with under-inhibited dosages of mono-ethylene glycol, we further demonstrated a significant improvement in the hydrate transportability, wherein this synergism led to a non-plugging scenario (flowable hydrate slurry). Our findings will offer new insights into the development of new anti-agglomerant chemistries.

Elucidating the Impact of Thermodynamic Hydrate Inhibitors and Kinetic Hydrate Inhibitors on a Complex System of Natural Gas Hydrates: Application in Flow Assurance

To alleviate the hydrate blockage risk in oil and gas pipelines/production facilities, thermodynamic hydrate inhibitors (THIs) and kinetic hydrate inhibitors (KHIs) are the frequently used additives/chemicals. While these additives are highly effective, the impact of low dosage of THIs (under inhibited systems) and performance of KHIs at high water cut and/or high subcooling is not well understood. In this work, a high-pressure visual stirred tank reactor was employed to investigate the impact of THIs and KHIs on the kinetics of the complex hydrates of natural gas mixtures (CH4/C2H6/C3H8) and cyclopentane at high water-cut and high subcooling (∼21 °C). Various concentrations of a THI, mono-ethylene glycol (MEG) with a dosage ranging from 0.1 to 25 wt %, and multiple KHIs (polyvinylpyrrolidone (PVP k-30, PVP k-90), caprolactam, butyl glycol ether (BGE), and polyglycerin with 0.1 wt % dosage) were evaluated for hydrate formation kinetics, onset hydrate formation/nucleation temperature, and morphological changes. Gas uptake results reveal that hydrate blockage risk is higher at low MEG content (0.1 to 10 wt %) compared to the baseline, while a significant reduction in gas uptake was observed for the high MEG content trials (20–25 wt %). With 20 and 25 wt % MEG, the hydrate nucleation temperature was reduced by 10–12 °C compared to the baseline. In context to KHIs impact, 0.1 wt % BGE and caprolactam promoted the nucleation temperature and the rate of hydrate formation/gas uptake. However, PVPs not only reduced the gas uptake kinetics but also lessened the hydrate nucleation temperature by 6–8 °C compared to the baseline data. Our results may offer new insights into optimizing hydrate inhibitors dosage to diminish the risk of hydrate blockage in subsea pipelines.

Survival of Nematode Larvae Strongyloides papillosus and Haemonchus contortus under the Influence of Various Groups of Organic Compounds

Many chemically synthesized xenobiotics can significantly inhibit the vitality of parasitic nematodes. However, there is yet too little research on the toxicity of such contaminating compounds toward nematodes. Compounds that are present in plants are able to inhibit the vitality of parasitic organisms as well. According to the results of our laboratory studies of toxicity, the following xenobiotics caused no decrease in the vitality of the larvae of Strongyloides papillosus and Haemonchus contortus: methanol, propan-2-ol, propylene glycol-1,2, octadecanol-1, 4-methyl-2-pen-tanol, 2-ethoxyethanol, butyl glycol, 2-pentanone, cyclopentanol, ortho-dimethylbenzene, dibutyl phthalate, succinic anhydride, 2-methylfuran, 2-methyl-5-nitroimidazole. Strong toxicity towards the nematode larvae was exerted by glutaraldehyde, 1,4-diethyl 2-methyl-3-oxobutanedioate, hexylamine, diethyl malonate, allyl acetoacetate, tert butyl carboxylic acid, butyl acrylate, 3-methyl-2-butanone, isobutyraldehyde, methyl acetoacetate, ethyl acetoacetate, ethyl pyruvate, 3-methylbutanal, cyclohexanol, cyclooctanone, phenol, pyrocatechin, resorcinol, naphthol-2, phenyl ether, piperonyl alcohol, 3-furoic acid, maleic anhydrid, 5-methylfurfural, thioacetic acid, butan-1-amine, dimethylformamide, 1-phenylethan-1-amine, 3-aminobenzoic acid. Widespread natural compounds (phytol, 3-hydroxy-2-butanone, maleic acid, oleic acid, hydroquinone, gallic acid-1-hydrate, taurine, 6-aminocaproic acid, glutamic acid, carnitine, ornithine monohydrochloride) had no negative effect on the larvae of S. papillosus and H. contortus. A powerful decrease in the vitality of nematode larvae was produced by 3,7-dimethyl-6-octenoic acid, isovaleric acid, glycolic acid, 2-oxopentanedioic acid, 2-methylbutanoic acid, anisole, 4-hydroxy-3-methoxybenzyl alcohol, furfuryl alcohol. The results of our studies allow us to consider 28 of the 62 compounds we studied as promising for further research on anti-nematode activity in manufacturing conditions.

Production of ethylene glycol monobutyl ether through etherification of ethylene glycol using a nanostructured heterogeneous catalyst of amyberlyst-15

This work aims to produce butyl glycol from the etherification of ethylene glycol (EG) and n-butanol (NB) using different heterogenous Amyberlyst-15 catalysts in a pressurized reactor tank. Experiments were designed by response surface methodology according to the central composite design (RSM-CCD). Three operating conditions of temperature (140–200 °C), reaction time (2–22 h), and EG: NB molar ratio (1:1–1:9) were considered to model and optimize the EG conversion under fixed pressure and catalyst weight. A quadratic conversion model was proposed as a function of independent and combined studied parameters, predicting the experimental data with high accuracy (R2 > 0.98). According to the response surface results, all variables positively affected the response. The optimal reaction condition for maximizing conversion was at 1:8.2, 4.1 h, and 200 °C, achieving the EG conversion of 86.12 %. Furthermore, the catalyst reusability was checked after four cycles, indicating a reduction of about 15 % in conversion after each cycle. The FESEM, FTIR, XRD, BET, and TGA analyses characterized the fresh catalyst and used catalyst after the fourth cycle. Both samples had a spherical morphology, and the used catalyst contained carbon-based sediments, intensifying the stretching vibration of C-O bond peaks. The pore diameter and volume of the fresh catalyst were 18.93 nm and 2.38 cm3/g, respectively, while these values were 22.07 nm and 0.36 cm3/g for the used catalysts after the fourth cycle. The reduction in the catalytic activity of the used sample can be because of the pore deformation.

THE POTENTIAL OF Azadirachta indica (NEEM TREE) LEAVES FOR BIOETHANOL PRODUCTION USING Zymomanas mobilis AS FERMENTING ORGANISMS

Bioethanol is a renewable energy produced from lignocellulosic biomass mainly by the fermentation process. It is used as an alternative to fossil fuel which doesn’t contribute to global warming. This research work was carried out to determining the potential of Neem tree leaves for bioethanol production. The process used in this study include pretreatment, hydrolysis fermentation and distillation. Hot water and Acid methods were used for the pretreatment. The hydrolysis of the substrate was carried out using Aspergillus niger for five days. Benedict test method was used to determine the reducing sugar concentration of the hydrolysate. The highest yield of 1500-2000 (mg/dl) was obtained equally for both the pre-treatment method. After hydrolysis, fermentation process was carried out for seven days using Zymomonas mobilis to ferment the hydrolysate. The fermented broth was separate using fractional distillation. Acid potassium dichromate was used to determine the concentration of the bioethanol produced. The results obtained shows that liquid hot water pretreatment produced the highest yield of 0.294±0.882 (mg/L) whereas alkaline method produced 0.282±.882 (mg/L) yield. Gas chromatography and mass spectroscopy analysis was also carried out to determine the presence of volatile compounds in the bioethanol produced. The highest volatile compound was Ethanol with 33.12% where Butyl Glycol was found to be least volatile compound with 6.22%. This result shows that Neem tree leaves is a good biomass for bioethanol production and pretreatment using Hot water method produced more bioethanol than Alkaline method of pretreatment.

Temporary 3D printed fixed dental prosthesis materials: Impact of post printing cleaning methods on degree of conversion as well as surface and mechanical properties.

To investigate the influence of different cleaning methods for additively manufactured fixed dental prostheses (FDPs) for long-term temporary use on the degree of conversion (DC), surface roughness, Martens parameters, and biaxial flexural strength. A total of 180 specimens per material (3Delta Etemp, DeltaMed; Freeprint Temp, Detax; Temp PRINT, GC Europe; Temp C&B and C&B MFH, NextDent; N = 180) were additively manufactured (D20 II, Rapid Shape) and subsequently cleaned by different methods: by rinsing for 5 minutes in acetone (Höfer Chemie; 99.5%); butyl glycol (Algin Chemie; 100%); ethanol (Otto Fischar; 96%); isopropanol (SAV LP; 100%); Yellow Magic 7 (Bradley Systems; 100%); or by applying centrifugal force for 4 minutes (n = 30 per subgroup). After postpolymerization (Otoflash G171, NK-Optik), the DC was measured using Raman spectroscopy, and the surface roughness, as well as the Martens parameters, were recorded. Biaxial flexural strength was investigated after artificial aging (thermocycling for 10,000 cycles). Data were statistically analyzed (Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests, and Pearson correlation coefficient). The highest DC was recorded after the use of butyl glycol or isopropyl (P < .001 to P = .047). The highest surface roughness was measured after the use of butyl glycol (P < .001 to P = .024). The use of centrifugal force or Yellow Magic resulted in the highest Martens parameter values (P < .001 to P = .036) and the highest biaxial flexural strength (P < .001 to P = .013), while acetone and butyl glycol led to the lowest values. The use of centrifugal force and Yellow Magic resulted in the highest Martens parameter values and the highest biaxial flexural strength. Concerning Yellow Magic, no negative effect on the mechanical properties was observed. The 3Delta Etemp material especially was prone to degradation after chemical cleaning.

Designing anti-migration furan-based plasticizers and their plasticization properties in poly (vinyl chloride) blends

The use of bio-based plasticizers with low toxicity and good compatibility with polyvinyl chloride (PVC) has attracted more attention in the recent years. With bio-based 2, 5-furandicarboxylic acid (FDCA) and butyl oligo-glycol ethers as raw materials, three liquid furan-based plasticizers of di(butyl glycol) furan-2,5-dicarboxylate, di(butyldiglycol) furan-2,5-dicarboxylate and di(butyltriglycol) furan-2,5-dicarboxylate were synthesized by direct esterification. The chemical structure of three plasticizers was characterized with FTIR, 1H NMR and 13C NMR. From DMA measurement, the glass transition temperature (Tg) of the plasticized PVC was decreased gradually when furan-based plasticizers were added to PVC formulation from 30 up to 50 phr. Due to lots of ether bonds in furan-based plasticizers, they expressed over two-fold lower migration in organic solvent compared with the traditional plasticizer diethylhexyl phthalate (DEHP). Through the characterization of elongation at break, hardness and thermal stability, furan-based plasticizers presented the same plasticization properties as DEHP, and had potential industrial application prospects.

Effect of coalescents on properties of protective styrene-acrylate latex coatings of oriented particle chipboards

It is necessary to note that in the production of finishing and protective materials for the surfaces of oriented chipboards, the most effective film former today is considered to be styrene-acrylate latex. However, the known styrene-acrylate dispersions have a minimum film formation temperature within 14–20 ° C, which doesn’t satisfy mass construction works. In order to obtain high-quality films in a wide range of temperatures, it is necessary to use special additives - coalescents. It was decided to use methoxypropanol, ethylene glycol and butyl glycol as coalescents. Their main selection criterion was the homogeneity of the resulting film and the absence of external defects. Based on the studies conducted, it was determined that the butyl glycol additive in the composition leads to the reduction in the elastic modulus of film coatings, which, in its turn, invariably leads to the increase in the relative elongation at break. The butyl glycol additive also enhances the film-forming and adhesive properties of styrene-acrylate latexes. According to the results of the experiments a composition with 4% wt. butyl glycol content as a coalescent was selected for further research.

Influence on Hydrate Dissociation for Methane Hydrates Formed in the Presence of PolyVinylCaprolactam versus PolyVinylCaprolactam + Butyl Glycol Ether

It has previously been shown that hydrates formed in the presence of efficient kinetic hydrate inhibitors (KHI) such as PolyVinylCaprolactam (PVCap) dissociate at temperatures above the equilibrium dissociation temperature of the uninhibited hydrates. The question regarding how hydrates form and dissociate as a function of time is an important issue for the industry. As KHI, commercial PVCap is commonly supplied in a solvent, e.g., butyl glycol ether (BGE), and the solvent acts as a synergist and improves the KHI performance of PVCap. In the present paper, the effect of BGE on dissociation of methane hydrates formed in the presence of PVCap has been examined. The pure BGE solvent showed no effect on the dissociation temperature at the applied concentrations. Two different molecular weight fractions of PVCap (Mw = 2k and 6k) have been tested either as pure substance or in mixture with BGE. The PVCap polymers have been synthesized in different solvents and stored for different periods of time prior to testi...

Influence of cosolvent retention on film formation and surface mechanical properties of water based acrylic coatings by atomic force microscopy

Abstract The influence of several common cosolvents on the level of film formation and surface mechanical properties of water-based acrylic coatings is investigated by atomic force microscopy (AFM) and AFM based nano-indentation technique. The amount of residual cosolvents in the coatings is determined and it is found that the aforementioned properties of coatings with the exact same polymer composition can be significantly different depending on the amount of residual cosolvents, which is related to the evaporation rate of the solvent as well as the interaction between the solvent, water and the polymer. Butyl glycol, for example, has good interaction with the acrylic polymer and water but due to its fast evaporation, does not improve film formation. Texanol, on the other hand, presents in the film at a large amount but it reduces the surface stiffness of the film and can have a detrimental effect on the surface mechanical properties of the coating.

Evaluation of chemical and mechanical resistance of virgin and recycled poly (ethylene terephthalate) and poly(methylene oxide) when applied as gravel pack in petroleum wells

Nowadays more and more unexpected uses for common materials have been observed, especially when recycled polymers are concerned. In this work, the viability for application of virgin and recycled poly(ethylene terephthalate) (PETvir and PETrec, respectively) and also poly(methylene oxide) (PMO) as granular materials (gravel) for gravel packing in sand control systems for unconsolidated sandstone reservoirs was studied. Polymer samples were tested in conditions similar to those observed in Campos Basin sandstone formations, in Brazilian Southwest (70 °C and 24.1 MPa). Samples were individually confined in roller cells with chemicals used in formation treatment: hydrochloric acid, pentapotassic DTPA salt (chelant Trilon CK) and in a mixture of diesel, xylene and butyl glycol. Mass loss was measured and the changes in molecular mass verified by size exclusion chromatography (SEC). Physical shape and grain size distribution were verified by scanning electron microscopy (SEM) and sieving tests. The effects over the polymeric gravel pack confinement resistance and permeability were evaluated using an API permeability cell. PMO proved to have a limited use, whereas PETrec and PETvir samples were not significantly affected, suggesting the viability of applying that recycled polymer in gravel packing for sand control in petroleum wells.

Development of new tissue conditioner using acetyl tributyl citrate and novel hyperbranched polyester to improve viscoelastic stability

ObjectiveThe objective was to develop a new tissue conditioner using acetyl tributyl citrate (ATBC), tributyl citrate (TBC), and a novel hyperbranched polyester (TAH) with long-term stable viscoelasticity. MethodsPlasticizers, i.e., ATBC, TBC, TAH (number-average molecular weight, 1306g/mol; weight-average molecular weight, 4245g/mol), butyl phthalyl butyl glycolate (BPBG), dibutyl phthalate (DBP), benzyl benzoate (BB), Shofu Tissue Conditioner II (Shofu), and GC Soft-Liner (GC), in nine combinations (ATBC+TAH, TBC+TAH, ATBC, TBC, BPBG, DBP, BB, Shofu, and GC), with gelation times between 120 and 180s were used; Shofu and GC were used for comparison. The dynamic viscoelasticity properties, i.e., shear storage modulus (G′), shear loss modulus (G″), loss tangent (tanδ), and complex dynamic shear modulus (G*) were determined at 37°C, using a rheometer, after immersion in water for 0, 1, 3, 7, 14, and 28 d. The surface hydrophobicity was examined using a static contact angle analyzer, and the biocompatibility was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Weight changes, solubility, and water absorption were measured using an analytical balance. ResultsTAH addition increased the viscoelastic stability; ATBC+TAH was the most stable among the tested groups. TAH decreased the contact angle and increased the water absorption, but decreased the ATBC solubility. The ATBC+TAH group biocompatibility was similar to those of the control group. SignificanceThe developed ATBC+TAH plasticizer has potential applications as a new tissue conditioner. Its clinical efficacy needs to be evaluated in clinical trials.

DEVELOPMENT AND OPTIMIZATION OF WATER BASED PAINT FORMULA IN ORDER TO REDUCE VOCs EMISSIONS

The interest in waterborne paints amelioration increased lately due to the toxicological effect of certain ingredients on human health, the restrictive environmental legislation and the depletion and escalation in price of raw materials. Research efforts in formulating waterborne paints are directed to insure low volatile organic compounds (VOCs) emission while maintaining and even improving their properties. This paper presents a waterborne paint formulation process. The required main ingredient was an alkydic resin with 51.3 % w/w non-volatile-matter content, 51.6 mg KOH/g acidity, 8.5 pH, 80 s flow time. Aiming the highest values for paint viscosity, elasticity and hardness and the lowest VOCs emission, the optimal composition concerning the resin neutralization, type and amounts of neutralization agents, co-solvents and water were determined by Response Surface Methodology (RSM). As consequence, the resin was neutralized with a mixture of ammonia and triethylamine in 1:1.8 ratio and solubilized with butanol and butyl glycol co-solvents (2.8:1 ratio). Pigments and filling material were used in a 2.6:1 ratio reported at resin content. The final product can be described as a homogenous, viscos fluid, with 152 s flow time and 22.5% VOCs content. In the optimized drying conditions, it formed a film with a fineness of 40 m, a semi-gloss aspect, a good adherence, an elasticity (after 7 days) of

Study on Preparation and Properties for Epoxy Shape Memory Polymer

A thermosetting epoxy shape memory polymer was obtained by adding modifier end thioglycolic acid butyl glycol ester which prepared in our lab into E-44/D-230. The results show that the tensile and impact strength of modified epoxy are improved, and it can be bended as U style in thermal transition temperature, shape fixed rate is 100% after removing external force. When temperature is raised to thermal transition temperature again, the shape of modified epoxy can be restored completely. The time of recovery is between 178~183s and not effected by cycle times.

Synthesis and Mechanical Property of Magnetic Polyurethane

Magnetic Polyurethane is synthesized by prepolymerization body method using PBA 2000, MDI, 1-4 butyl glycol and magnetic chain extender, which is synthesized by a method involving the use of dimethylol propionic acid (DMPA) and ferrous powder in dimethylformamide as solvent conditions. The mechanical property of magnetic polyurethane is measured by servo control computer system tension tester,Shore hardness of magnetic polyurethane is measured by LX-A type Shore rubber hardness tester.

Solubilisation of preservatives: interaction of benzoic acid with short-chain glycol ethers in water and in aqueous polysorbate 80 solution

Abstract Using a potentiometric titration technique, ethylene glycol mono-ethers (Me, Et, n-Bu, Ph) and diglycol mono-ethers (Me, Et) have been shown to cause elevation of pH in benzoic acid-sodium benzoate solutions. The butyl glycol ether is shown to form micelles; critical micelle concentration values are given and the “loss” of benzoic acid from aqueous solution is considered. In mixtures with polysorbate 80, the glycol ethers increase the uptake of benzoic acid by the micelles.

Sol–gel preparation and characterization of anti-reflective and self-cleaning SiO 2–TiO 2 double-layer nanometric films

Glass substrates were first coated with SiO 2 and then TiO 2 by dipping into sols which were prepared by two different methods involving complex formation and hydrolysis, using ethanol (EtOH) or butyl glycol (BG). Concentration of TiO 2 in the sols was kept at 0.1 and 0.5 wt%. Prepared coatings were investigated by field-emission scanning electron microscope (FESEM), atomic force microscope (AFM), hazemeter, UV–visible spectrophotometer and goniometer. Rhodamine B (RhB) photodegradation tests were performed in order to evaluate photocatalytic activity. Application of SiO 2 as the bottom layer increased the transmittance by 6% points, thereby compensated for the loss of transmittance caused by the TiO 2 self-cleaning top layer. Pencil-hardness values of the obtained coatings were in 5B–3H range. TiO 2 coatings obtained from sols containing 0.5% TiO 2 and BG solvent represented the highest photocatalytic activity, with a rate constant of 0.44 ppm −1 h −1 and a half period of 5.5 h. Self-cleaning surfaces were obtained while maintaining the anti-reflectance.