Triethylene Glycols Research Articles

Iron(III) Sensors Based on the Fluorescence Quenching of Poly(phenylene ethynylene)s and Iron-Detecting PDMS Pads

The detection of Fe ions is critical to environmental monitoring and disease diagnosis. We herein report fluorescent conjugated polymers that exhibit fluorescence quenching upon the addition of Fe (III) ions with the total concentration of 2 ppm. The polymer backbone consists of poly(phenylene ethynylene) (PPE) with side-chains bearing triethylene glycols or alkyl groups. The quenching phenomenon was analyzed by the Stern-Volmer equation, and the resulting Stern-Volmer constants show that the alkyl functional PPE presents higher sensitivity than the triethylene glycol functional PPE, which was unexpected. The polymer sensors showed the selectivity in that the Stern-Volmer constants for Fe3+ are 2–3 times higher than those for Na+, K+, and Ca2+. Time-resolved photoluminescence spectroscopy revealed that the quenching is static, indicating that there may be coordination between Fe (III) and alkyne/phenyl groups in the PPE backbone. For practical applications, we produced a PPE-containing, fluorescent polydimethylsiloxane (PDMS) pad. Dropping Fe solution like an ink on the pad exhibits a dark stain, demonstrating the scheme of producing Fe-detecting flexible pads for future applications in wearable sensor technology.

Volumetric and ultrasonic studies of molecular interactions of glycols in aqueous glutaraldehyde solutions at different temperatures

In the current work, Density and speed of sound (ultrasonic speed) of liquid mixtures of (ethylene, diethylene and triethylene glycols + aqueous glutaraldehyde solutions) have been investigated at the temperature ranges of (293.15 K, 298.15 K, 303.15 K and 308.15 K) and in the concentration of (0.01, 0.02, 0.03 and 0.04) mol·kg−1. Different thermodynamic and acoustic parameters have also been calculated using density and speed of sound experimental values. Vϕ (apparent molar) and Vϕ0 (partial molar) volumes and ΔVϕ0 (partial molar volume of transfer) have been estimated using experimental values of density. Using speed of sound values, Kϕ, s (apparent molar) and Kϕ, s0 (partial molar) isentropic compressions and ΔKϕ, s0 (partial molar isentropic compression of transfer) have been obtained. Using partial molar volume of transfer and partial molar isentropic compression of transfer values, the pair and triplet interaction coefficients have also been computed. The final outcome of the research is studied in terms of solute-solvent interactions between the molecules of liquid mixtures.

Theoretical and experimental ultrasonic velocities Comparison of binary mixtures of triethylene glycols and glycerol at different temperatures

The densities and sound velocities of binary mixtures of triethylene glycol are measured at different temperatures and at frequency of 2 MHz over entire range of mole fraction. Various theoretical models, such as Nomoto, Impedance, Junjie, Van Dael and Vangeel, have been used to measure theoretical ultrasonic velocities. The average percentage error was estimated and the chi-square fitness test was also used to check the validity of theoretical models. The variance from the experimental results is interpreted in terms of molecular interactions between the components of the binary mixtures.

Liquid–Liquid Equilibria for Benzene/Thiophene + Cyclohexane/Hexadecane + Deep Eutectic Solvents: Data and Correlation

The experimental liquid–liquid equilibria (LLE) for several systems containing benzene or thiophene + cyclohexane or hexadecane + choline chloride-based deep eutectic solvents (DESs) including mono-, di-, and triethanolamines and mono-, di-, and triethylene glycols were measured at T = 298.15 to 308.15 K and atmospheric pressure. The distribution coefficients (β) and selectivities (S) were calculated to evaluate the efficiency of the studied solvents for aromatics (benzene or thiophene) extraction from nonaromatic phases. Generally, the selectivity values decrease with increasing of the temperature for our studied DESs. The Othmer–Tobias equation was used to ensure the consistency of the obtained LLE data. The nonrandom two-liquid (NRTL) and universal quasi-chemical (UNIQUAC) models were used to correlate the experimental LLE data. The Hansen solubility parameters confirm the performance of the studied DESs for benzene and thiophene extraction. The measured LLE data in this study shows better performance ...

Synthesis of optically active macrolides bearing di- and triethylene glycol and dicarboxylic acid hydrazide moieties from (-)-α-pinene

Six optically active macroheterocycles bearing ester and dihydrazide moieties were synthesized from available natural (-)-α-pinene through the intermediate keto acid, (31R,33R)- 1-hydroxy-32,32-dimethyl-1,4-dioxopentaphane, using the [2+1] reaction of this keto acid with di- or triethylene glycols and the [1+1] condensation of the resulting α,ω-diketo diesters with dicarboxylic acid dihydrazides in the key steps.

Viscosity of liquid diethylene, triethylene and tetraethylene glycols at moderately high pressures using a vibrating wire instrument

New viscosity measurements of compressed liquid diethylene glycol (DiEG), triethylene glycol (TriEG) and tetraethylene glycol (TeEG) have been performed using a vibrating wire instrument operated in the forced oscillation mode. The measurements have been carried out in a range of pressures up to 70 MPa and temperatures from (293–363) K, covering a total range of viscosities from (3.46–1.15 × 102) mPa⋅s.Complementary experimental density data were obtained for the same glycols using an Anton Paar vibrating U-tube densimeter. These measurements have been performed in a range of temperatures from about (283–363) K and at pressures up to about 70 MPa.The viscosity results were correlated with density, using a modified hard-spheres scheme. The experimental density data were correlated, as a function of temperature and pressure, with a modified Tait-type equation.The expanded uncertainty of the present viscosity results at a 95% confidence level is estimated to be less than ±2.0% for viscosities up to 68 mPa s and less than ±2.6% for higher viscosities. The densities have an expanded uncertainty of ±0.2% at a 95% confidence level.

Effect of Ethylene, Diethylene, and Triethylene Glycols and Glycerol on the Physicochemical Properties and Phase Behavior of Benzyltrimethyl and Benzyltributylammonium Chloride Based Deep Eutectic Solvents at 283.15–343.15 K

Deep eutectic solvents (DESs) are regarded as a promising and emerging alternative for volatile organic compounds (VOCs) due to their cost-effectiveness and environmentally sustainable nature. Formulation of new DESs and thorough investigation of their physicochemical properties have been on the rise ever since potential applications of DES have been realized. The present study reports a new series of DES based on benzyltrimethylammonium chloride and benzyltributylammonium chloride as hydrogen bond acceptor (HBAs) with three ethylene glycols and glycerols as hydrogen bond donors (HBDs). The current work includes the synthesis, characterization, and investigation of the thermophysical properties of a series of DES systems. The studied properties include density, ρ, speed of sound, u, viscosity, η, refractive index, nD, and electrical conductivity, σ, for all DESs in the temperature range from 283.15 to 343.15 K. The observed trends in properties like density, speed of sound, viscosity, and refractive indic...

Effect of Replacing Alkyl Side Chains with Triethylene Glycols on Photovoltaic Properties of Easily Accessible Fluorene-Based Non-Fullerene Molecular Acceptors: Improve or Deteriorate?

Hydrophilic oligo(ethylene glycol) (OEG) side chains are more flexible than alkyl chains and can facilitate the π–π stacking of conjugated polymer backbones, which has been proven to be a key structural feature leading to better device performance in polymer:fullerene blend polymer solar cells (PSCs). So far, little has been known about the influence of OEG side chains on the performance of non-fullerene acceptors in polymer:non-fullerene acceptor blends. Based on an easily accessible conjugated backbone of dicyanomethylene indanone–thiophene–fluorene–thiophene–dicyanometnylene indanone (DICTF), two non-fullerene molecular acceptors were synthesized with decyl (DICTF-C10) and triethylene glycol monoether (DICTF-TEG) side chains to blend with the polymer donor of PTB7-Th for PSCs. Replacing the decyl side chains with the TEGs on DICTF does improve the π–π stacking between the conjugated backbones as expected. For DICTF-TEG, nevertheless, forming the BHJ blend with the PTB7-Th donor leads to unfavorable fil...

Effect of Replacing Alkyl Side Chains with Triethylene Glycols on Photovoltaic Properties of Easily Accessible Fluorene-Based Non-Fullerene Molecular Acceptors: Improve or Deteriorate?

Effect of Replacing Alkyl Side Chains with Triethylene Glycols on Photovoltaic Properties of Easily Accessible Fluorene-Based Non-Fullerene Molecular Acceptors: Improve or Deteriorate?

Diketopyrrolopyrrole-Based Conjugated Polymer Entailing Triethylene Glycols as Side Chains with High Thin-Film Charge Mobility without Post-Treatments.

Side chain engineering of conjugated donor–acceptor polymers is a new way to manipulate their optoelectronic properties. Two new diketopyrrolopyrrole (DPP)‐terthiophene‐based conjugated polymers PDPP3T‐1 and PDPP3T‐2, with both hydrophilic triethylene glycol (TEG) and hydrophobic alkyl chains, are reported. It is demonstrated that the incorporation of TEG chains has a significant effect on the interchain packing and thin‐film morphology with noticeable effect on charge transport. Polymer chains of PDPP3T‐1 in which TEG chains are uniformly distributed can self‐assemble spontaneously into a more ordered thin film. As a result, the thin film of PDPP3T‐1 exhibits high saturated hole mobility up to 2.6 cm2 V−1 s−1 without any post‐treatment. This is superior to those of PDPP3T with just alkyl chains and PDPP3T‐2. Moreover, the respective field effect transistors made of PDPP3T‐1 can be utilized for sensing ethanol vapor with high sensitivity (down to 100 ppb) and good selectivity.

Synthesis of 2-(diphenylphosphoryl)phenyl ethers of ethylene glycols and structure of their sodium and potassium complexes

Phase-transfer catalysis and template assembly on sodium and cesium cations were used to prepare 2-(diphenylphosphoryl)phenyl ethers of ethylene glycols L n with varied number of polyether units (n = 3–8). Previously unknown dinitro and disulfo derivatives of 2-(diphenylphosphoryl)phenyl ethers of di- and triethylene glycols were synthesized. Complexes [NaL4]NCS·C6H6, [NaL4]ClO4, [KL5]NCS, and [KL5]ReO4 were synthesized, and their crystal structure was studied. Structure–stability constant correlations were found for alkali metal complexes with phosphoryl podands L n and isodentate crown ethers.

Self-organization of TiO2 nanotubes in mono-, di- and tri-ethylene glycol electrolytes

Self-organization of TiO2 nanotubes was studied by means of titanium anodizing in electrolytes containing 1, 2 and 3 oxyethylene units in the organic chain of solvent molecule, named mono-, di-, and tri-ethylene glycols. A fundamentally different nanostructures were formed in mono- and di-electrolytes in view of their self-organization; close pack nanotubes are formed in mono-electrolyte, whereas nanotubes with large spaceing in-between are formed in di-electrolyte. The analysis of the tube bottoms and dimples formed in substrate shows formation of conical-type (alumina like) and frustum-type dimples in mono- and di-electrolytes, respectively. We discuss on the formation of frustum-type dimples with the size corresponding to the space in-between the nanotubes and link their formation to the mechanism of nanostructure growth.

Modeling of Toluene Sulfonic Acid Catalyzed Oxide Addition Reaction for Soy-Based Polyol

Polyol oligomers formed from reactions of mono-, di-, and triethylene glycols with epoxidized soybean oil were synthesized and the reaction conversions were modeled. The data verified the effectiveness of a model that is based on the simultaneous solution of eight ordinary differential equations. In addition, the data demonstrated that di- and triethylene glycols produced lower viscosity oligomers than monoethylene glycol. Since the model is fundamentally based, it provides insight into the reaction mechanisms and allows for simulation of reaction conditions with reasonable extrapolation. Within the accuracy of the data, the reaction rate coefficients for all alcohol and epoxy moieties were equal, independent of the molecule to which they were attached—reaction rates varied based only on temperature and dilution of reacting moieties. The model provides an effective means to simulating concentration, viscosity, and temperature profiles including estimates of degrees of polymerization, which are dependent on a parameter related to inter versus intra-oligomerization.

Alkoxylation of 4-chloronitrobenzene with aliphatic alcohols and glycols in the presence of NaOH

The reaction of 4-chloronitrobenzene with aliphatic C1−n-C4 alcohols and with mono-, di-, and triethylene glycols in the presence of NaOH in liquid ammonia at 15–50°C was studied.

Alkoxylation of 3,6-di-tert-butyl-1,2-benzoquinone. New bis-1,2-benzoquinones

Alkoxylation of 3,6-di-tert-butyl-1,2-benzoquinone with a number of diols, including propane-1,3-diol, butane-1,4-diol, di-, and triethylene glycols, and cyclohexane-1,4-diyldimethanol, was studied. Nine new 4-alkoxy-3,6-di-tert-butyl-1,2-benzoquinones were synthesized, four of which were bis-1,2-benzoquinones with different tethers (6–13 atoms) between the quinone fragments. Depending on the length of the chain between the hydroxy groups in glycols, bicyclic 4,5-disubstituted 3,6-di-tert-butyl-1,2-benzoquinones were formed or their stepwise alkoxylation occurred. The newly synthesized o-benzoquinone derivatives can be reduced with alkali metals to give radical anions and converted into semiquinone chelates with manganese carbonyl.

Synthesis of poly(p-phenyleneethynylene)s bearing oligo-ethylene glycols and their gas permeation properties

1,4-Diiodobenzenes bearing oligo-ethylene glycols [IRC6H2IR, R = OCH2CH2OCH3 (1a), O(CH2CH2O)2CH3 (1b), O(CH2CH2O)3CH3 (1c)] were polymerized with 1,4-diethynylbenzene in the presence of Pd/Cu catalyst to afford poly(p-phenyleneethynylene)s bearing oligo-ethylene glycols (2a–c), respectively. Polymer 2a was insoluble in any solvents, but the other polymers (2b, 2c) were soluble in CHCl3. The weight-average molecular weights of 2b and 2c were 5.4 × 104 and 9.6 × 104, respectively, and they gave free-standing membranes by solution-casting method. The densities of membranes of 2b and 2c were 1.26 and 1.22 g/cm3, respectively, and their carbon dioxide permeability coefficients were 12.9 and 13.5 barrers, respectively. The CO2/N2 separation factor of membrane of 2b was as large as 33.7. Membrane of 3b, which contains triethylene glycols, exhibited higher CO2 permselectivity, and the CO2/N2 separation factor was 50.0.

A determination of the activity of water in water–alcohol mixtures using mobile order thermodynamics

The non-ergodic theory of mobile order thermodynamics (MOT) is employed to study how the structure of ethylene glycol and several common alcohols influences the activity of water in binary mixtures. Results suggest that alcohol molecules with a smaller alkyl group or a greater number of hydroxyl groups are more effective at lowering the activity of water. The influence of alcohol branching among isomers is examined as well. Calculations are in good agreement with widely used algorithms such as the UNIQAC equation. With more complex alcohols like diethylene and triethylene glycols, the MOT framework requires additional development. Alcohols are known to be thermodynamic inhibitors that hinder the formation of gas hydrates. Since hydrate stability is determined by an equilibrium condition of equal chemical potentials for water in the hydrate and liquid phases, the present study may help clarify the inhibition mechanism for alcohols.

Spectral characterization and colloidal properties of 1-hexadecylpyridinium chloride in aqueous binary mixtures of different glycols

The influence of various water–glycol mixed solvents on the self-assembly of 1-hexadecylpyridinium chloride (CPyCl) was investigated using electrical conductivity and spectroscopic measurements. Temperature studies were performed in aqueous mixtures of ethylene, diethylene, triethylene and tetraethylene glycols (abbreviated as EG, DEG, TEG and TeEG, respectively). The correlation among critical micellization concentration (cmc) and degree of ionization ( β) was discussed in term of thermodynamic parameters or the changes in the Gibbs free energy, enthalpy and entropy upon micelle formation ( Δ G m 0 , Δ H m 0 and Δ S m 0 ). The differences in the Gibbs energies of micellization of CPyCl between water and binary solvents were determined to evaluate the influence of the cosolvent. This study allowed us to conclude that the ability of glycols to act, as a structure breaker and its interaction with the surfactant hydrophilic groups are the controlling factors of the micellization process. The effect of cosolvents on the size of the aggregates was analyzed by means of density measurements. Micellar micropolarity and solute solvent parameters were examined spectrophotometrically using methyl orange (MO) as a probe. The increase in micellar microviscosity was revealed from fluorescence measurements. The mechanism of docking of surfactant and the probe molecules in the system were obtained by using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy.

Formation of poly(ethylene phosphates) in polycondensation of H3PO4 with ethylene glycol. Kinetic and mechanistic study

AbstractConditions of synthesis of poly(ethylene phosphates) in reaction of H3PO4 with HOCH2CH2OH (EG), the actual path of polycondensation, and structure of the obtained polymers (mostly oligomers) and kinetics of reaction are described. Preliminary kinetic information, based on the comparison of the MALDI‐TOF‐ms and 31P{1H} NMR spectra as a function of conversion is given as well. Because of the dealkylation process fragments derived from di‐ and triethylene glycols are also present in the repeating units. Structures of the end groups (CH2CH2OH or OP(O)(OH)2) depend on the starting ratio of [EG]0/[H3PO4]0, although even at the excess of EG the acidic end groups prevail because of the dealkylation process. In MALDI‐TOF‐ms products with Pn equal up to 21 have been observed. The average polymerization degrees (Pn) are lower and have been calculated from the proportion of the end groups. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 830–843, 2008

Excess molar volumes and deviations of the relative permittivity of the binary mixtures of 2-propoxyethanol with diethylene, triethylene, and tetraethylene glycols at various temperatures

Densities and relative permittivities at T = (293.15, 298.15, and 303.15) K in the binary liquid mixtures of 2-propoxyethanol with diethylene glycol, triethylene glycol, and tetraethylene glycol have been measured over the entire mixture compositions. These data have been used to compute the excess molar volumes and deviations of the relative permittivity. The results are discussed in terms of intermolecular interactions in the bulk of studied the binary mixtures.