Conductivity of Porous Phosphate-Silicate Glass Synthesized with Non-Ionic Surfactant

Porous, phosphate-silicate glass with high-conductivity and nano-size pores was synthesized through a xero-gel route, using non-ionic surfactant polyethylene glycol monocetyl ether (Brij 56) to control pore size. The influences of Brij 56 concentration on pore size and conductivity under different humidity were studied by measuring conductivity and calculating the volume ratio of adsorbed-water to pore volume. Samples prepared with 0.1 wt% Brij 56 had 5.2 nm pore size, 0.91 volume ratio, and narrower pore size distribution than other samples. The nano-size pores were filled with water, which in pores of 5.2 nm is mostly chemically bonded with the hydroxyl groups on the pore surfaces, resulting in higher conductivity than other samples in high relative humidity (over 55%).

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Spectroscopic study of the surface of zeolite Y. Part 4.—Infra-red studies of structural hydroxyl groups and adsorbed water on some transition metal ion-exchanged zeolites

Transactions of the Faraday Society ◽

10.1039/tf9716701489 ◽

1971 ◽

Vol 67 (0) ◽

pp. 1489-1499 ◽

Cited By ~ 12

Author(s):

John W. Ward

Keyword(s):

Transition Metal ◽

Spectroscopic Study ◽

Metal Ion ◽

Zeolite Y ◽

Adsorbed Water ◽

Hydroxyl Groups ◽

Transition Metal Ion ◽

Infra Red ◽

Structural Hydroxyl

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Surface-Ionized thermosensitive poly(N-isopropylacryl amide) hydrogels with faster response

e-Polymers ◽

10.1515/epoly.2007.7.1.1052 ◽

2007 ◽

Vol 7 (1) ◽

Author(s):

Xiao Xin-Cai

Keyword(s):

Volume Ratio ◽

Temperature Cycling ◽

Solution Temperature ◽

Hydroxyl Groups ◽

Critical Solution Temperature ◽

Temperature Responsive ◽

Microgel Particles ◽

Concentrated Sulfuric Acid ◽

Response To Temperature ◽

First Time

AbstractPoly(N-isopropylacrylamide) hydrogels have been successfully modified by concentrated sulfuric acid for the first time. The modified hydrogels displayed faster, larger magnitude and hydration/dehydration dynamic response to temperature cycling without increasing the lower critical solution temperature (LCST). These contributions were attributed to sulphate ester groups resulting from terminal hydroxyl groups of poly(N-isopropylacrylamide). These results may lead to technological application for temperature-responsive thin film and microgel particles with higher surface-to-volume ratio.

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A Robust, Tough and Multifunctional Polyurethane/Tannic Acid Hydrogel Fabricated by Physical-Chemical Dual Crosslinking

Polymers ◽

10.3390/polym12010239 ◽

2020 ◽

Vol 12 (1) ◽

pp. 239 ◽

Cited By ~ 1

Author(s):

Jie Wen ◽

Xiaopeng Zhang ◽

Mingwang Pan ◽

Jinfeng Yuan ◽

Zhanyu Jia ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Polyethylene Glycol ◽

Hydrogen Bonds ◽

Tannic Acid ◽

Hydroxyl Groups ◽

Self Healing ◽

Physical Chemical ◽

Biomedical Field ◽

Physical Crosslinking

Commonly synthetic polyethylene glycol polyurethane (PEG–PU) hydrogels possess poor mechanical properties, such as robustness and toughness, which limits their load-bearing application. Hence, it remains a challenge to prepare PEG–PU hydrogels with excellent mechanical properties. Herein, a novel double-crosslinked (DC) PEG–PU hydrogel was fabricated by combining chemical with physical crosslinking, where trimethylolpropane (TMP) was used as the first chemical crosslinker and polyphenol compound tannic acid (TA) was introduced into the single crosslinked PU network by simple immersion process. The second physical crosslinking was formed by numerous hydrogen bonds between urethane groups of PU and phenol hydroxyl groups in TA, which can endow PEG–PU hydrogel with good mechanical properties, self-recovery and a self-healing capability. The research results indicated that as little as a 30 mg·mL−1 TA solution enhanced the tensile strength and fracture energy of PEG–PU hydrogel from 0.27 to 2.2 MPa, 2.0 to 9.6 KJ·m−2, respectively. Moreover, the DC PEG–PU hydrogel possessed good adhesiveness to diverse substrates because of TA abundant catechol groups. This work shows a simple and versatile method to prepare a multifunctional DC single network PEG–PU hydrogel with excellent mechanical properties, and is expected to facilitate developments in the biomedical field.

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Biocompatibility and Functional Performance of a Polyethylene Glycol Acid-Grafted Cellulosic Membrane for Hemodialysis

The International Journal of Artificial Organs ◽

10.1177/039139880002300603 ◽

2000 ◽

Vol 23 (6) ◽

pp. 356-364 ◽

Cited By ~ 22

Author(s):

V. Sirolli ◽

S. Di Stante ◽

S. Stuard ◽

L. Di Liberato ◽

L. Amoroso ◽

...

Keyword(s):

Polyethylene Glycol ◽

Functional Performance ◽

Sialyl Lewis X ◽

Hydroxyl Group ◽

Hydroxyl Groups ◽

Dialysis Session ◽

Cellulose Diacetate ◽

Activation Markers ◽

Surface Hydroxyl ◽

Cellular Expression

In order to improve the biochemical reactivity of the cellulose polymer, which is mainly attributed to the presence of surface hydroxyl groups, derivatized cellulosic membranes have been engineered replacing or masking some or all of the hydroxyl groups in the manufacturing process of the membrane. The present study was set up to analyze both biocompatibility and functional performance of two different derivatized cellulosic membranes (cellulose diacetate; polyethylene glycol, PEG, acid-grafted cellulose) as compared to a synthetic membrane (polymethylmethacrylate, PMMA). Cellulose diacetate is prepared by substituting hydroxyl groups with acetyl groups; PEG cellulose is obtained by grafting PEG chains onto the cellulosic polymer with a smaller amount of substitution than cellulose diacetate. While the three dialyzers provided similar urea and creatinine removal, the dialyzer containing cellulose diacetate showed a reduced ability to remove β2-microglobulin compared to that containing PEG cellulose or PMMA. A transient reduction in leukocyte count was observed for both derivatized cellulosic membranes. The neutrophil and monocyte counts throughout the entire dialysis session showed a closer parallelism with the cellular expression of the adhesive receptor CD15s (sialyl-Lewis x molecole) than with CD11b/CD18 expression. Platelet activation, as indicated by the percentage of cells expressing the activation markers CD62P (P-selectin) and CD63 (gp53), occurred with all membranes at 15 min of dialysis and also with PMMA at 30 min. An increased formation of platelet-neutrophil and platelet-monocyte coaggregates was found at 15 and 30 min during dialysis with cellulose diacetate and PMMA but not with PEG cellulose. Generally in concomitance with the increase in platelet-neutrophil coaggregates, an increased hydrogen peroxide production by neutrophils occurred. Our results indicate that derivatizing cellulose may represent a useful approach to improve the biocompatibility of the cellulose polymer, though some homeostatic reactions remain activated. Our results also indicate that there may be a great variability in the biocompatibility profile of derivatized cellulosic membranes which most likely stem from the different type of structural modification rather than from the degree of hydroxyl group replacement.

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Relaxation Dynamics in Polyethylene Glycol/Modified Hydrotalcite Nanocomposites

Polymers ◽

10.3390/polym10111182 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1182 ◽

Cited By ~ 3

Author(s):

Rossella Arrigo ◽

Diego Antonioli ◽

Massimo Lazzari ◽

Valentina Gianotti ◽

Michele Laus ◽

...

Keyword(s):

Polyethylene Glycol ◽

Polymer Matrix ◽

Complex Viscosity ◽

Gas Chromatography Mass Spectrometry ◽

Hydroxyl Groups ◽

Thermal Treatments ◽

Relaxation Dynamics ◽

Unusual Behavior ◽

Melt Mixing ◽

Grafting Reactions

Polyethylene glycol-based nanocomposites containing an organo-modified hydrotalcite with loadings ranging from 0.5 to 5 wt.% were prepared by melt mixing performed just above the melting point of the polymer matrix. In these conditions, the dispersion of the nanofiller within the polymer matrix was quite homogeneous as revealed by TEM analyses. The effect of various thermal treatments and filler loadings was thoroughly investigated by means of rheological, morphological and gas chromatography-mass spectrometry, hyphenated to thermogravimetry analysis tests. Unfilled polyethylene glycol exhibited a continuous decrease in complex viscosity upon heating. In contrast, the complex viscosity of nanocomposites containing nanofiller loadings higher than 1 wt.% showed first a decrease, followed by an increase in the complex viscosity as the temperature increases, exhibiting a minimum between 130 and 140 °C. Annealing at 180 °C for different times further increased the viscosity of the system. This unusual behavior was explained by the occurrence of grafting reactions between the –OH terminal groups of the polyethylene glycol chains and the hydroxyl groups of the organo-modified filler, thus remarkably affecting the relaxation dynamics of the system.

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A study on cell surface hydrophobicity, growth and metabolism of Zymomonas mobilis influenced by PEG as a pretreatment agent

RSC Advances ◽

10.1039/c5ra03181h ◽

2015 ◽

Vol 5 (60) ◽

pp. 48176-48180

Author(s):

Niloofar Nasirpour ◽

Seyyed Mohammad Mousavi ◽

Seyed Abbas Shojaosadati

Keyword(s):

Polyethylene Glycol ◽

Cell Surface ◽

Zymomonas Mobilis ◽

Cell Surface Hydrophobicity ◽

Surface Hydrophobicity ◽

Ionic Surfactant ◽

Peg 4000

This study investigates the effects of polyethylene glycol (PEG) 4000, a non-ionic surfactant, on the cell surface hydrophobicity (CSH) ofZymomonas mobilis, as well as its growth and metabolism.

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Prediction of soil water retention properties using pore-size distribution and porosity

Canadian Geotechnical Journal ◽

10.1139/cgj-2012-0320 ◽

2013 ◽

Vol 50 (4) ◽

pp. 435-450 ◽

Cited By ~ 25

Author(s):

Christopher T.S. Beckett ◽

Charles E. Augarde

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Soil Water ◽

Water Retention ◽

Adsorbed Water ◽

Retention Data ◽

Soil Water Retention ◽

Pore Size Distributions ◽

Water Retention Properties

Several models have been suggested to link a soil's pore-size distribution to its retention properties. This paper presents a method that builds on previous techniques by incorporating porosity and particles of different sizes, shapes, and separation distances to predict soil water retention properties. Mechanisms are suggested for the determination of both the main drying and wetting paths, which incorporate an adsorbed water phase and retention hysteresis. Predicted results are then compared with measured retention data to validate the model and to provide a foundation for discussing the validity and limitations of using pore-size distributions to predict retention properties.

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Effects of Non-Ionic Surfactant on the Deep Temperature Flotation Agents of Hematite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.2354 ◽

2012 ◽

Vol 538-541 ◽

pp. 2354-2357 ◽

Cited By ~ 2

Author(s):

Xiao Jun Jiang ◽

Yun Jin Wang ◽

Hong Bo Xu ◽

Jian Wang

Keyword(s):

Surface Tension ◽

Fatty Acid ◽

Polyethylene Glycol ◽

Sodium Oleate ◽

Ionic Surfactant ◽

Low Carbon ◽

Optimal Composition ◽

Different Temperatures ◽

Deep Temperature ◽

Tension Methods

This investigation involves the effects of non-ionic surfactant materials on the industrial sodium oleate, sodium naphthenate and their mixtures at different temperatures by the surface tension methods. The effects on the critical micelle concentration (CMC) of sodium oleate were assessed by the Toween 80(T-80) presence, polyethylene glycol, polyether and other non-ionic surfactant. T-80 was proved more effective than other non-surfactant in increasing the sodium oleate CMC at same concentration. Using the optimal composition of sodium fatty acid and the surfactant can reduce the temperature of separation hematite from 43°C to 23°C, achieve the purpose of low carbon and energy saving.

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Characterization of Clays and Clay-organic Complexes

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v50i4.3469 ◽

1969 ◽

Vol 50 (4) ◽

pp. 303-315

Author(s):

Raúl Pérez Escolar

Keyword(s):

Organic Materials ◽

Adsorbed Water ◽

Exchange Capacity ◽

Hydroxyl Groups ◽

No Adsorption ◽

X Ray ◽

Organic Complexes ◽

Poorly Drained Soils ◽

Active Residue

Information is presented with reference to the infrared spectroscopy of blackstrap molasses, rum distillery slops, the active fraction of the slops, clays of four poorly drained soils, and of the complexes formed between organic materials and the clays of Fe, Guanica, Whippany, and Evesboro soils. The X-ray spectroscopy of two of the clays of montmorillonitic nature and of the complexes formed with the organic materials is also shown. Characteristic peaks of the organic materials include those caused by hydroxyl, methyl, amino, methoxy, carbonyl, and ketonic groups. The spectra of the clays showed peaks which are attributed to hydroxyl, bonded and unbonded, adsorbed water, silica tetrahedra, and aluminum octahedra. Hydrogen-bonding occurred between the exposed hydroxyl groups of the clay crystals and the molasses, slops, and its active residue. There was no shift in the 2 angle of diffraction of the expanding-laitice clays, indicating that there was no adsorption in the interlamellar spaces. The adsorption was possible at the edges of the crystal. This finding was strengthened by the fact that rather than undergoing a decrease in cation-exchange capacity there was a slight increase in the expending lattice clays.

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