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The high-efficient development of shale oil is one of the urgent problems in the petroleum industry. The technology of CO2 enhanced oil recovery (EOR) has shown significant effects in developing shale oil. The effects of several glycol ether additives with low molecular weight on the interactions between CO2 and oil were investigated here. The solubility of glycol ether additive in CO2 was firstly characterized. Then, the effects of glycol ether additives on the interfacial tension (IFT) between CO2 and hexadecane and the volume expansion and extraction performance between CO2 and hexadecane under different pressures was investigated. The experimental results show that diethylene glycol dimethyl ether (DEG), triethylene glycol dimethyl ether (TEG), and tetraethylene glycol dimethyl ether (TTEG) all have low cloud point pressure and high affinity with CO2. Under the same mass fraction, DGE has the best effect to reduce the IFT between hexadecane and CO2 by more than 30.0%, while an overall reduction of 20.0%–30.0% for TEG and 10.0%–20.0% for TTEG. A new method to measure the extraction and expansion rates has been established and can calculate the swelling factor accurately. After adding 1.0% DEG, the expansion and extraction amounts of CO2 for hexadecane are respectively increased to 1.75 times and 2.25 times. The results show that glycol ether additives assisted CO2 have potential application for EOR. This study can provide theoretical guidance for the optimization of CO2 composite systems for oil displacement.

Some propylene glycol ethers (PGEs) have been associated with reproductive toxicity. Ethoxypropanol (PGEE) and propoxypropanol (PGPE) are two common PGEs found in many commercial products. Although skin exposure is frequent when handling such products, no studies have investigated their skin absorption. Neat or aqueous concentrations of PGEs were applied with different concentrations on previously frozen human skin according to OECD guidelines. We also explored the use of frozen skin for skin irritation screening. Our results show that both PGEs readily permeate human skin (permeation coefficients: KpPGEE = 0.0005–0.002 cm/h; KpPGPE = 0.0002–0.002 cm/h; rates: JPGEE = 447.5–1075.2 µg/cm2/h; JPGPE = 193.9–826.1 µg/cm2/h; and time lag: 2–5 h). The permeability rate was four times greater for PGPE diluted in water compared to neat, and double for PGEE. Increasing the water content increased PGEE skin permeation but had no effect on PGPE. Cleaning products contain 1–5% PGEs, and water-based paints 10–50%, thus increasing the potential for skin uptake in consumers. Our skin irritation results were inconsistent, so we conclude that skin irritation cannot be assessed with previously frozen human skin. Future studies should assess the irritation using fresh skin and investigate the risk of health effects from PGEs exposures.

The performance of solid polymer electrolytes is characterized by lower ionic conductivity than conventional liquid electrolytes but provides advantages in terms of operational safety. A quasi-solid polymer electrolyte (QSPE) based on a new plasticizer 4,7,10,13-tetraoxahexadecane-1,16-dinitrile (bCN-PEG4) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) incorporated into a polyacrylates matrix was successfully prepared via UV-induced copolymerization. The matrix consists of units of trimethylolpropane ethoxylate triacrylate (ETPTA), poly(ethylene glycol) diacrylate (PEGDA), and the monoacrylate poly(ethylene glycol) methyl ether acrylate (mPEGa). The QSPE containing 55 wt% bCN-PEG4 exhibits highly uniform morphology, thermal stability > 200 °C, ionic conductivity of 1.8 × 10−4 S cm−1 at 30 °C, and 1.3 × 10−3 S cm−1 at 80 °C, coupled with very high electrochemical stability (> 5 V vs. Li/Li+) and a low glass transition temperature (− 55.7 °C). A cycling experiment in a Li/QPSE/Li cell setup demonstrated the compatibility toward lithium metal additionally. The bCN-PEG4 offers an overall satisfying performance as a plasticizer in a poly(ethylene oxide)-based solid polymer electrolyte. The new QSPE is an alternative to dinitrile-based (e.g., succinonitrile) or glycol ether-based (e.g., tetraglyme) plasticizers with application potential in high-voltage lithium-ion batteries.

The demand for energy continues to increase as the global economy continues to grow. The role of oilfield chemicals in the process of oil and gas exploration, development, and production is becoming more and more important, and the demand is rising year by year. The support of national policies and the formulation of environmental protection regulations have put forward higher requirements for oilfield chemical products, which has promoted the innovative research and development and market application of oilfield chemicals. Polyformaldehyde glycol ether polymer (PGEP) is simple to synthesize, easily biodegradable, green and environmentally friendly, and in line with the development trend of chemicals used in oil and gas development. The interfacial tension performance of PGEP after compounding with different surfactants can reach as low as 0.00034 mN/m, which meets the requirements of the oilfield (interfacial tension ≤ 5 × 10−3 mN/m). The best oil washing efficiency performance of PGEP compounded with different surfactants reached 78.2%, which meets the requirements of the oilfield (oil washing efficiency ≥ 40%). The fracturing fluid drainage efficiency of PGEP after compounding with different surfactants reaches 22%, which meets the requirements of the oilfield (drainage efficiency ≥ 15%). The surface interfacial tension of the system remains constant after the concentration exceeds 0.2% and decreases with lower concentrations. The drainage efficiency increases with increasing concentrations in the range below 0.6%. It was determined that PGEP can be used as a surfactant instead of fatty-alcohol ethoxylates (FAE) in oilfield development.

A total of 11 bacterial strains capable of completely degrading 2-butoxyethanol (2-BE) were isolated from forest soil, a biotrickling filter, a bioscrubber, and activated sludge, and identified by 16S rRNA gene sequence analysis. Eight of these strains belong to the genus Pseudomonas; the remaining three strains are Hydrogenophaga pseudoflava BOE3, Gordonia terrae BOE5, and Cupriavidus oxalaticus BOE300. In addition to 2-BE, all isolated strains were able to grow on 2-ethoxyethanol and 2-propoxyethanol, ethanol, n-hexanol, ethyl acetate, 2-butoxyacetic acid (2-BAA), glyoxylic acid, and n-butanol. Apart from the only gram-positive strain isolated, BOE5, none of the strains were able to grow on the nonpolar ethers diethyl ether, di-n-butyl ether, n-butyl vinyl ether, and dibenzyl ether, as well as on 1-butoxy-2-propanol. Strains H. pseudoflava BOE3 and two of the isolated pseudomonads, Pseudomonas putida BOE100 and P. vancouverensis BOE200, were studied in more detail. The maximum growth rates of strains BOE3, BOE100, and BOE200 at 30 °C were 0.204 h−1 at 4 mM, 0.645 h−1 at 5 mM, and 0.395 h−1 at 6 mM 2-BE, respectively. 2-BAA, n-butanol, and butanoic acid were detected as potential metabolites during the degradation of 2-BE. These findings indicate that the degradation of 2-BE by the isolated gram-negative strains proceeds via oxidation to 2-BAA with subsequent cleavage of the ether bond yielding glyoxylate and n-butanol. Since Gordonia terrae BOE5 was the only strain able to degrade nonpolar ethers like diethyl ether, the degradation pathway of 2-BE may be different for this strain.

Two environmentally friendly methodologies based on ultrasound-assisted extraction (UAE) and micro-matrix solid-phase dispersion (µMSPD) followed by gas chromatography-mass spectrometry (GC-MS) analysis are proposed for the first time for the simultaneous analysis of 17 glycols, glycol ethers, and their acetates in cosmetics. These sample preparation approaches result in efficient and low-cost extraction while employing small amounts of sample, with a low consumption of reagents and organic solvents. The use of a highly polar column allows for the direct analysis of the obtained extracts by GC-MS without a previous derivatization step, drastically reducing the sample preparation time and residues and thus complying with green analytical chemistry (GAC) principles. Both the UAE and µMSPD methodologies were validated in terms of linearity, accuracy, and precision, providing satisfactory results. LODs were found to be lower than 0.75 µg g−1, allowing the determination of trace levels of the forbidden target compounds. Finally, the validated methodologies were applied to real cosmetics and personal care products, showing suitability, and providing a reliable and useful tool for cosmetics control laboratories.

A beneficial technique, using glycol ethers, to help reduce the amount of amorphous organic matter (AOM) in palynological preparations is described. A brief history of glycol ethers, and their historical applications, is also discussed. The technique, which is relatively simple, inexpensive and rapid, can easily be applied as a terminal step to most maceration schedules. The technique does not appear to have any deleterious effect on palynomorphs, but testing treated and non-treated residues is recommended. Two examples, one Late Devonian and one Middle Pennsylvanian in age, are provided to illustrate the effectiveness of glycol ethers in removing AOM.

Hydrophobic base stacking is a major contributor to DNA double-helix stability. We report the discovery of specific unstacking effects in certain semihydrophobic environments. Water-miscible ethylene glycol ethers are found to modify structure, dynamics, and reactivity of DNA bymechanisms possibly related to a biologically relevant hydrophobic catalysis. Spectroscopic data and optical tweezers experiments show that base-stacking energies are reduced while base-pair hydrogen bonds are strengthened. We propose that a modulated chemical potential of water can promote “longitudinal breathing” and the formation of unstacked holes while base unpairing is suppressed. Flow linear dichroism in 20% diglyme indicates a 20 to 30% decrease in persistence length of DNA, supported by an increased flexibility in single-molecule nanochannel experiments in poly(ethylene glycol). A limited (3 to 6%) hyperchromicity but unaffected circular dichroism is consistent with transient unstacking events while maintaining an overall average B-DNA conformation. Further information about unstacking dynamics is obtained from the binding kinetics of large thread-intercalating ruthenium complexes, indicating that the hydrophobic effect provides a 10 to 100 times increased DNA unstacking frequency and an “open hole” population on the order of 10−2 compared to 10−4 in normal aqueous solution. Spontaneous DNA strand exchange catalyzed by poly(ethylene glycol) makes us propose that hydrophobic residues in the L2 loop of recombination enzymes RecA and Rad51 may assist gene recombination via modulation of water activity near the DNA helix by hydrophobic interactions, in the manner described here. We speculate that such hydrophobic interactions may have catalytic roles also in other biological contexts, such as in polymerases.

In this study, we aim to synthesize self-assembled amphiphilic diblock poly(PEGA- b -HEA-PCL) copolymers through RAFT living polymerization, targeting the delivery of hydrophobic anticancer drugs. The synthesized self-assembled diblock copolymers polymeric micelles (PMs) comprising poly(ethylene glycol) methyl ether acrylate (PEGA), as a hydrophilic segment and 2-hydroxyethyl acrylate-polyhexanoate monomer (HEA-PCL) with different block lengths, as a hydrophobic segment. The chemical structures, compositions, and self-assembled behavior were identified through 1 H NMR spectroscopy. The thermal stability was assessed through TGA and DSC. Furthermore, DOX was encapsulated into all PMs. The drug-loaded PMs exhibited enhanced drug release profiles in acidic medium. Particle diameter was measured through DLS and TEM techniques. The cell viability of diblock polymers and selected DOX-loaded PMs were evaluated against non-cancerous (L929) and cancerous cells (SK-N-AS), respectively, through well-known MTT assay. Micellar aggregates with mean diameters of approximately 127.2–145.3 nm formed in aqueous solution. The diameters of PMs increased to 141.5–173.1 nm upon the incorporation of DOX. The drug loading content and encapsulation efficiency of PMs were approximately 8.09–18.84% and 30.43–54.07%, respectively. The MTT assay results indicated that all synthesized materials had minimal effects on the viability of L929 cells, while DOX-loaded materials inhibited the viability of neuroblastoma cells by 68.7%. The highest drug release was 89.20% at pH 7.4, while 83.45% at pH 5.0 for 40 h. These findings suggest that the synthesized amphiphilic PMs are promising candidates for drug delivery systems.

The first polymer containing phosphate groups was prepared by esterification of polyacrylic acid with polyethylene glycol phosphate. The second polymer was prepared by copolymerizing ethylene glycol monovinyl polyethylene glycol ether with hydroxy butyl phosphate methacrylate and acrylic acid. Then, the first and second polymers were uniformly mixed in proportion to prepare the highly dispersed and high-slump-resistant polycarboxylate superplasticizer (PCE-P). The structure of PCE-P was characterized by infrared spectroscopy (FTIR) gel chromatography (GPC) and concrete experiments. The results show that PCE-P can be used to control the construction performance of high adsorption machine-made sand concrete, and has strong practical value and broad market prospects.