Post-crosslinked polymer adsorbents and their properties for separation of furfural from aqueous solutions

In this paper, we adopted a simple and efficient strategy to prepare a β-cyclodextrin (β-CD)-modified hyper-crosslinked polymer (CDM-HCP). The structures and physicochemical properties of the as-synthesized polymer were also evaluated. It was applied to the removal of anilines from aqueous solutions. The introduction of β-CD into the hyper-crosslinked polymer significantly enhanced adsorption properties for the removal of various amines. The adsorption kinetics agreed with the pseudo-second-order mode very well. The adsorption isotherm data of p-methylaniline (p-MA) and p-aminobenzoic acid (p-ABC) were in agreement with the Langmuir isotherm, whereas aniline and p-chloroaniline (p-CA) were fitted best with the Freundlich model. The maximum adsorption capacities (qmax) determined by adsorption isotherms were 148.97 mg/g for aniline, 198.45 mg/g for p-MA, 293.71 mg/g for p-CA, and 622.91 mg/g for p-ABC, respectively. It had higher adsorption capacities than those of some commercial polymeric resins, such as XAD-4, PA66, and AB-8. The interaction mechanism was investigated by FTIR, XPS, and the ONIOM2 method. A CDM-HCP can be regenerated efficiently and used repeatedly, indicating its potential technological applications in removing organic pollutants from actual industrial effluents.

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Hydrogels as potential drug-delivery systems: network design and applications

Therapeutic Delivery ◽

10.4155/tde-2020-0114 ◽

2021 ◽

Author(s):

Hina Shoukat ◽

Khuda Buksh ◽

Sobia Noreen ◽

Fahad Pervaiz ◽

Irsah Maqbool

Keyword(s):

Drug Delivery ◽

Aqueous Solutions ◽

Biomedical Applications ◽

Drug Delivery Systems ◽

Specific Drug ◽

Potential Drug ◽

Physiological Conditions ◽

Crosslinked Polymer ◽

External Stimuli ◽

Hydrophilic Network

Hydrogels are 3D crosslinked polymer matrices having a colossal tendency to imbibe water and exhibit swelling under physiological conditions without deformation in their hydrophilic network. Hydrogels being biodegradable and biocompatible, gained consideration due to some unique characteristics: responsiveness to external stimuli (pH, temperature) and swelling in aqueous solutions. Hydrogels offer a promising option for various pharmaceutical and biomedical applications, including tissue-specific drug delivery at a predetermined, controlled rate. This article presents a brief review of the recent and fundamental advances to design hydrogels, the swelling and deswelling mechanism, various crosslinking methods and their use as an intelligent carrier in the pharmaceutical field. Recent applications of hydrogels are also briefly discussed and exemplified.

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Evaluation of polyaromatic hydrocarbon removal from aqueous solutions using activated carbon and hyper-crosslinked polymer (Macronet MN200)

Journal of Chemical Technology & Biotechnology ◽

10.1002/jctb.2030 ◽

2009 ◽

Vol 84 (2) ◽

pp. 236-245 ◽

Cited By ~ 15

Author(s):

César Valderrama ◽

Xavier Gamisans ◽

Jose L Cortina ◽

Adriana Farrán ◽

F Xavier de las Heras

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Polyaromatic Hydrocarbon ◽

Crosslinked Polymer ◽

Hydrocarbon Removal

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DEVELOPMENT OF A NOVEL CROSSLINKED POLYMER FOR DYES ADSORPTION FROM CONTAMINATED AQUEOUS SOLUTIONS

10.21698/simi.2021.ab03 ◽

2021 ◽

Author(s):

Iolanda Viorica Ganea ◽

◽

Alexandrina Nan ◽

Calin Baciu ◽

Rodica Turcu ◽

...

Keyword(s):

Aqueous Solutions ◽

Crosslinked Polymer ◽

Dyes Adsorption

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Ultrathin frozen sections of yeast without aldehyde prefixation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081152 ◽

1978 ◽

Vol 36 (2) ◽

pp. 58-59

Author(s):

K. J. Böhm ◽

a. E. Unger

Keyword(s):

Aqueous Solutions ◽

Biological Material ◽

Yeast Cells ◽

Frozen Sections ◽

Good Preservation ◽

Ultrathin Frozen Sections

During the last years it was shown that also by means of cryo-ultra-microtomy a good preservation of substructural details of biological material was possible. However the specimen generally was prefixed in these cases with aldehydes.Preparing ultrathin frozen sections of chemically non-prefixed material commonly was linked up to considerable technical and manual expense and the results were not always satisfying. Furthermore, it seems to be impossible to carry out cytochemical investigations by means of treating sections of unfixed biological material with aqueous solutions.We therefore tried to overcome these difficulties by preparing yeast cells (S. cerevisiae) in the following manner:

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Freeze-etch TEM of aqueous polymer gel network morphology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145327 ◽

1986 ◽

Vol 44 ◽

pp. 796-797

Author(s):

J. A. N. Zasadzinski ◽

R. K. Prud'homme

Keyword(s):

Metal Ion ◽

Polymer Network ◽

Polymer Gels ◽

Polymer Gel ◽

Deformation History ◽

Crosslinked Polymer ◽

Aqueous Polymer ◽

History Of ◽

Gel Network ◽

Network Morphology

The rheological and mechanical properties of crosslinked polymer gels arise from the structure of the gel network. In turn, the structure of the gel network results from: thermodynamically determined interactions between the polymer chain segments, the interactions of the crosslinking metal ion with the polymer, and the deformation history of the network. Interpretations of mechanical and rheological measurements on polymer gels invariably begin with a conceptual model of,the microstructure of the gel network derived from polymer kinetic theory. In the present work, we use freeze-etch replication TEM to image the polymer network morphology of titanium crosslinked hydroxypropyl guars in an attempt to directly relate macroscopic phenomena with network structure.

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Imaging polymers, proteins and dna in aqueous solutions with the atomic force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152136 ◽

1989 ◽

Vol 47 ◽

pp. 32-33

Author(s):

S.A.C. Gould ◽

B. Drake ◽

C.B. Prater ◽

A.L. Weisenhorn ◽

S.M. Lindsay ◽

...

Keyword(s):

Amino Acids ◽

Dna Sequencing ◽

Aqueous Solutions ◽

Atomic Force Microscope ◽

Piezoelectric Crystal ◽

Atomic Force ◽

Structure Of Molecules ◽

Optical Lever

The atomic force microscope (AFM) is an instrument that can be used to image many samples of interest in biology and medicine. Images of polymerized amino acids, polyalanine and polyphenylalanine demonstrate the potential of the AFM for revealing the structure of molecules. Images of the protein fibrinogen which agree with TEM images demonstrate that the AFM can provide topographical data on larger molecules. Finally, images of DNA suggest the AFM may soon provide an easier and faster technique for DNA sequencing.The AFM consists of a microfabricated SiO2 triangular shaped cantilever with a diamond tip affixed at the elbow to act as a probe. The sample is mounted on a electronically driven piezoelectric crystal. It is then placed in contact with the tip and scanned. The topography of the surface causes minute deflections in the 100 μm long cantilever which are detected using an optical lever.

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The analysis of “Gels” in polymer films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153786 ◽

1989 ◽

Vol 47 ◽

pp. 362-363

Author(s):

G. M. Brown ◽

D. F. Brown ◽

J. H. Butler

Keyword(s):

Molecular Weight ◽

Film Industry ◽

Local Stress ◽

Melt Index ◽

Polyethylene Films ◽

Crosslinked Polymer ◽

Polymeric Gels ◽

Mineral Particles ◽

Polymeric Species ◽

Special Concern

The term “gel”, in the jargon of the plastics film industry, may refer to any inclusion that produces a visible artifact in a polymeric film. Although they can occur in any plastic product, gels are a principle concern in films where they detract from the cosmetic appearance of the product and may compromise its mechanical strength by acting as local stress concentrators. Many film gels are small spheres or ellipsoids less than one millimeter in diameter whereas other gels are fusiform-shaped and may reach several centimeters in length. The actual composition of gel inclusions may vary from miscellaneous inorganics (i.e. glass and mineral particles) and processing additives to heavily oxidized, charred or crosslinked polymer. The most commonly observed gels contain polymer differing from the bulk of the sample in its melt viscosity, density or molecular weight.Polymeric gels are a special concern in polyethylene films. Over the years and with the examination of a variety of these samples three predominant polymeric species have been observed: density gels which have different crystallinity than the film; melt-index gels in which the molecular weight is different than the film and crosslinked gels which are comprised of crosslinked polyethylene.

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