Presence Of Diethylene Glycol Research Articles

A novel route to α,ω-telechelic poly(ɛ-caprolactone) diols, precursors of biodegradable polyurethanes, using catalysis by decamolybdate anion

A new convenient route for the synthesis of poly(ɛ-caprolactone) (PCL) with α,ω-telechelic diols' end-groups is presented. Synthesis of α,ω-telechelic PCL diols (HOPCLOH) was achieved by ring-opening polymerization (ROP) of ɛ-caprolactone (CL) catalyzed with ammonium decamolybdate (NH 4) 8[Mo 10O 34] and using diethylene glycol (DEG) as initiator. Obtained HOPCLOH was characterized by 1H and 13C NMR, FT-IR, GPC and MALDI-TOF. Comparative studies demonstrate that ammonium decamolybdate (NH 4) 8[Mo 10O 34] is better catalyst than Sn-octanoate (SnOct 2) toward CL polymerization in presence of DEG, under the conditions tested. A biodegradable poly(ester-urethane-urea) derivative was efficiently prepared from synthesized HOPCLOH. Obtained polymer shows minor differences with respect to the properties recorded for a poly(ester-urethane-urea) obtained from commercial HOPCLOH.

Fatal Encephalopathy and Renal Failure Caused by Diethylene Glycol Poisoning

Diethylene glycol poisoning results in multiorgan dysfunction and requires a high index of suspicion for diagnosis. We report 11 patients of diethylene glycol poisoning, all of whom had renal failure and severe encephalopathy. The diagnosis was established by the presence of diethylene glycol in the paracetamol elixir consumed by these children; the amount of which ranged from 2.3 to 23% w/W. Consumption of large amount of toxin resulted in severe encephalopathy and high mortality in these children.

Effect of adding glycols to the micellar properties of Tween: small-angle neutron scattering and turbidity measurements

Small-angle neutron scattering (SANS) and turbidity measurements have been carried out on the nonionic surfactants Tween 20 and Tween 80, in the presence of diethyleneglycol (DEG), triethyleneglycol (TEG), ethylene glycol monoethyl ether (EGMEE), and ethyleneglycol mono butyl ether (EGMBE). SANS measurements show that the shapes of the Tween 20 and Tween 80 micelles are oblate ellipsoidal, which do not change predominantly in the presence of DEG and TEG. However, the presence of EGMBE and EGMEE reduces the aggregation number of Tween. This has been attributed to the solubilization of EGMBE and EGMEE in the Tween micelles, providing them with additional hydrophobicity.

Biosynthesis of natural-synthetic hybrid copolymers: polyhydroxyoctanoate-diethylene glycol.

A new natural-synthetic hybrid biomaterial has been isolated from the growth of Pseudomonas oleovorans in the presence of diethylene glycol (DEG). DEG was consumed by P. oleovorans with 20 mM sodium octanoate in modified E* medium, but its presence in the fermentation medium retarded cell growth and viability, influencing production and composition of polyhydroxyalkanoates with medium chain length substituents (mclPHAs) and consequently attenuating PHA yield. DEG affected the composition of the mclPHA with an increase in the C8 component: polyhydroxyoctanoate (PHO). Gas chromatography-mass spectrometry (GC-MS) was used to quantitatively monitor DEG in the system and reveal its cellular adsorption and penetration. Intracellularly, the DEG significantly reduced the molar mass of the mclPHA; PHO with a bimodal distribution of high and low molecular weight fractions was observed. 1H NMR, 2-D COSY, and heteronuclear single quantum coherence spectra confirmed that the high molecular weight fraction consisted of PHO chains terminated by DEG. Thus, the synthesis of this natural-synthetic hybrid copolymer, PHO-DEG, opens the way for microbial synthesis of a wide variety of PHA-DEG copolymers with a range of bioactive properties.

Preparation and chain-extension of P(LLA-b-TMC-b-LLA) triblock copolymers and their elastomeric properties

ABA triblock copolymers ofL-lactide and trimethylene carbonate with several different compositions were prepared by sequential ring-opening polymerization in the presence of diethylene glycol. Also chain-extension reactions of the resulting copolymers were carried out using hexamethylene diisocyanate to produce relatively high molecular weight polymers, which could be cast into elastomeric tough films. The polymers with certainL-lactide contents were partially crystalline, exhibiting two-phase morphology. The polymer films showed reversible elastic behavior under tensile tension, providing a novel thermoplastic elastomer possessing desirable properties such as biodegradability and good mechanical properties.

Equilibrium Data for Methane, Ethane, and Propane Incipient Hydrate Formation in Aqueous Solutions of Ethylene Glycol and Diethylene Glycol

Equilibrium experimental data for methane, ethane, and propane incipient hydrate formation in the presence of diethylene glycol and that for propane in the presence of ethylene glycol were obtained. Forty-six experiments were performed in the temperature and pressure ranges (264 to 283) K and (0.181 to 4.5) MPa, respectively, using the pressure search method. The experimental data were compared with predictions made using a hydrate equilibrium calculation method. The average deviation between the experimental data and calculated values was found to be 4.91%.

Change in permselectivity between sulfate and chloride ions through anion exchange membrane with hydrophilicity of the membrane

The transport number of sulfate ions relative to chloride ions through an anion exchange membrane was measured by electrodialyzing a sodium sulfate and sodium chloride mixed solution containing diethylene glycol after immersing the membrane in diethylene glycol because the membrane had good affinity to ethylene glycol and diethylene glycol. The transport number of sulfate ions relative to chloride ions increased in the presence of diethylene glycol in the membrane. This is due to the increase in the uptake of sulfate ions in the membrane compared with chloride ions, not to the change in a ratio of mobilities of both anions.

Investigation of the effects of diethylene glycol on the hydration of C3S and C3A pastes

The effects of diethylene glycol on the hydration characteristics of tricalcium silicate and tricalcium aluminate pastes were studied. Diethylene glycol acts as a retarder in the hydration of C3S, and as an accelerator in the hydration of C3A. The amount of Ca(OH)2 found in pastes of C3S treated with diethylene glycol was lower, the induction period increased and the formation of hydrates was retarded. For C3A pastes, hydration in the presence of diethylene glycol accelerated the formation of the hexagonal aluminate hydrates and promoted the conversion to the cubic form.