Poly Ethylene Oxide
Mostrando 1-12 de 60 artigos, teses e dissertações.
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1. Per-Aqueous Liquid Chromatography for the Separation of Polar Compounds Preparation and Characterization of Poly(ethylene oxide co dimethylsiloxane) Based Stationary Phase
Poly(ethylene oxide-co-dimethylsiloxane) was thermally immobilized on silica particles-Si(PEO)-to separate small polar compounds with water-rich mobile phases. Poly(ethylene oxide-co-dimethylsiloxane) content on Si(PEO) stationary phase was optimized using a central composite design. Infrared spectroscopy, scanning electron microscopy, and thermogravimetric
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Incorporation of Fluorescent Dyes in Electrospun Chitosan/Poly(ethylene oxide)
Polymeric films have been increasingly investigated due to the ease of miniaturization and integration in several sensor devices. Films obtained from the electrospinning technique have a controlled diameter and homogeneity, and substances can be incorporated into the polymeric network. Electrospinning fiber of chitosan (Ch) and poly(ethylene oxide) (PEO) was
J. Braz. Chem. Soc.. Publicado em: 2021-05
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3. New Insights into the Partitioning of Phenothiazine Dyes in Aqueous Two-Phase Systems
Aqueous two-phase systems (ATPSs) have proven to be efficient and environmentally safe methods for extracting chemical species. However, the driving forces behind the partition of solutes in these systems are still little understood. A complete thermodynamic partitioning of phenothiazine dyes was investigated in poly(ethylene oxide) (PEO) + salt + water ATPS
J. Braz. Chem. Soc.. Publicado em: 2020-08
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4. A Sustainable Methodology to Extract Bismuth from Secondary Sources
Bismuth is a critical metal broadly used in cosmetic, medicine and metallurgy. However, its scarcity in Earth’s crust may impair further applications. An alternative is to recover bismuth from secondary sources. In this work, a methodology to extract bismuth from safety valves of discharged gas cylinders is proposed. Extraction and purification of bismuth
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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5. Micellar propolis nanoformulation of high antioxidant and hepatoprotective activity
ABSTRACT The present study reports a promising antioxidant protection by a recently developed micellar propolis formulation, against oxidative stress in in vitro and in vivo models of toxicity. The formulation, based on poplar propolis encapsulated in poly(ethylene oxide)–β-poly(propylene oxide)–β-poly(ethylene oxide) triblock copolymer (PEO26–PPO40�
Rev. bras. farmacogn.. Publicado em: 26/08/2019
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6. Synthesis and characterization of amphiphilic block copolymers by transesterification for nanoparticle production
Abstract Poly(ε-caprolactone)-block-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, triblock) and Poly(ε-caprolactone)-block-(poly(ethylene oxide)−poly(propylene oxide)−poly(ethylene oxide)-poly (ε-caprolactone) (PCL-PEO-PPO-PEO-PCL, pentablock) copolymers were synthesized by transesterification with reduction of PCL molecular mass, enabling
Polímeros. Publicado em: 04/07/2019
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7. Soil Biodegradation of PLA/CNW Nanocomposites Modified with Ethylene Oxide Derivatives
Due to its ester bonds, poly(lactic acid) (PLA) undergoes biodegradation in humid environments, attracting market attention. The goal of this work was to observe the biodegradation in garden soil of PLA nanocomposites with neat (PLA/CNW) and surfactant modified cellulose nanowhiskers (PLA/CNW/S). Three types of surfactants were tested: poly(ethylene glycol)
Mat. Res.. Publicado em: 01/03/2018
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8. Degradation of Poly(Ethylene Oxide) Films Using Crystal Violet
The present study aimed to investigate the degradation of poly(ethylene oxide) (PEO) in the presence of cationic dye crystal violet irradiated under visible light. The preparation of the samples was done in the form of films obtained by casting. Degradation tests were carried out by 120 hours at room temperature. The degradation kinetics of the dye and polym
Mat. Res.. Publicado em: 01/02/2018
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9. Effect of Acetonitrile and N,N-Dimethylformamide on the Formation of Poly(ethylene oxide)-Sodium Alkyl Sulfate Aggregates
The effects of low contents of acetonitrile (AN) or N,N-dimethylformamide (DMF) on the aggregation of sodium alkyl sulfate surfactants, in the absence and presence of poly(ethylene oxide) (PEO), were investigated using conductivity and isothermal titration calorimetry. The cosolvents slightly changed the critical micellar concentrations and did not alter the
J. Braz. Chem. Soc.. Publicado em: 2018-01
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10. Synergistic Effect in Drug Solubility by New Binary Micelles of Poly(ε-caprolactone)-poly(ethylene oxide) and F127®
Binary mixtures of block copolymers E114CL20 and E97P69E97 (F127(®)) were prepared in order to tailor a drug delivery system with synergistic effect, concerning dilution stability and high drug solubility. Both reduction of the critical micelle concentrations (CMC) values and enhance hydrophobic drug solubility in F127/E114CL20 mixtures (30-50 wt.%) were ob
J. Braz. Chem. Soc.. Publicado em: 2017-07
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11. Hydrocortisone release from tablets based on bioresorbable poly(ether-ester-urethane)s
Abstract Bioresorbable linear poly(ether-ester-urethane)s with different hydrophilic characteristics were synthesized from triblock copolymers of poly(ε-caprolactone)-poly(ethylene oxide)-poly(ε-caprolactone) (PCL-PEO) as macrodiols, and L-lysine diisocyanate (LDI) or hexamethylenediisocyanate (HDI) were used as the required diisocyanates. Macrodiols were
Braz. J. Pharm. Sci.. Publicado em: 20/04/2017
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12. Preparation of Polymeric Micelles of Poly(Ethylene Oxide-b-Lactic Acid) and their Encapsulation With Lavender Oil
Nanoparticles comprised of the poly(ethylene oxide)-b-poly (lactic acid) diblock copolymer (PEO-b-PLA) with and without the incorporation of lavender oil were prepared by nanoprecipitation. Diblock copolymers based on a fixed PEO block (5KDa) and two different PLA segments (4.5 or 10KDa) were used. The morphology, encapsulation efficiency, essential oil-poly
Mat. Res.. Publicado em: 03/10/2016