Surfactant-Induced Collapse of Polymer Chains and Monodisperse Growth of Aggregates near the Precipitation Boundary in Carboxymethylcellulose−DTAB Aqueous Solutions

Langmuir ◽  
2003 ◽  
Vol 19 (2) ◽  
pp. 230-237 ◽  
Author(s):  
Samuel Guillot ◽  
Michel Delsanti ◽  
Sylvain Désert ◽  
Dominique Langevin
Keyword(s):  
Aqueous Solutions ◽  
Polymer Chains ◽  
Precipitation Boundary

scholarly journals Effects of the Hydrophilic–Lipophilic Balance of Alternating Peptides on Self-Assembly and Thermo-Responsive Behaviors

2019 ◽  
Vol 20 (18) ◽  
pp. 4604 ◽  
Author(s):  
Ihsan ◽  
Nargis ◽  
Koyama
Keyword(s):  
Aqueous Solutions ◽  
Self Assembly ◽  
Polymer Chains ◽  
Systematic Evaluation ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Hydrophilic Lipophilic Balance ◽  
Upper Critical Solution Temperature ◽  
Cloud Points ◽  
Micellization Behavior

A series of N-substituted poly(Gly–alter–Val) peptides were successfully synthesized for the systematic evaluation of the micellization behavior of alternating peptides. Three-component polymerization employing an aldehyde, a primary ammonium chloride, and potassium isocyanoacetate afforded four alternating peptides in excellent yields. We investigated the dependence of the hydrophilic–lipophilic balance of alternating peptides on the micellization behavior. All the aqueous solutions of alternating peptides exhibited upper critical solution temperature (UCST) behaviors, strongly indicating that the alternating binary pattern would mainly contribute to the UCST behaviors. The cloud points of alternating peptides shifted to higher temperatures as the side chains became more hydrophilic, which is opposite to the trend of typical surfactants. Such unusual micellization behaviors appeared to be dependent on the quasi-stable structure of single polymer chains formed in water.

PHOTOLYSIS OF POLYMETHACRYLIC ACID IN AQUEOUS SOLUTIONS

1964 ◽  
Vol 42 (3) ◽  
pp. 522-531 ◽  
Author(s):  
C. H. Chou ◽  
H. H. G. Jellinek
Keyword(s):  
Aqueous Solutions ◽  
Chain Length ◽  
Polymer Chain ◽  
Irradiation Time ◽  
Polymer Concentration ◽  
Chain Scission ◽  
Polymer Chains ◽  
Polymethacrylic Acid ◽  
Degree Of Ionization ◽  
Ph Values

The photolysis of polymethacrylic acid was studied in aqueous solutions as a function of pH, polymer concentration, polymer chain length, and small additions of electrolytes in the absence of oxygen with light of wavelength 2537 Å. The random chain scission constants decrease with increasing pH values. Small variations in polymer chain length and concentration and electrolyte concentration have no effect on the photolysis. Changes in the ultraviolet spectra with irradiation time are more pronounced at low pH values than higher ones. It is shown that the decrease in susceptibility to photolysis with increasing degree of ionization of the acid is not proportional to the decrease or increase of the number of COOH or COO− groups respectively. It is rather due to the same causes—that is changes in ionic atmosphere— which make the polymer chains uncoil with increasing ionization.

scholarly journals Removal of anthracene from aqueous solutions using modified magnetic Fe3O4 nanoparticles by dendrimer polymer chains and 4-aminophenol Ligandide

2020 ◽  
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Process ◽  
Polymer Chains ◽  
Isotherm Models ◽  
Operational Parameters ◽  
X Ray Diffraction ◽  
Residual Concentration ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
The Fourier Transform

Background: Anthracene is an organic compound and environmentally resistant pollutant that causes severe damage to human health due to toxic and carcinogenic properties. The present study aimed to investigate the efficiency of magnetic dendrimer nano-adsorbent for the removal of anthracene from aqueous solutions. Methods: In this study, the synthesized iron oxide nanoparticles were modified by dendrimer polymer chains and 4-aminophenol ligand. The Fourier-transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy were conducted to examine the nano-absorbent properties. Different operational parameters in the adsorption process in batch and laboratory conditions were also studied, and the adsorbent reusability was correspondingly examined in this study. The residual concentration of anthracene in aqueous solution was determined and reported by a spectrophotometer. Findings: Optimization results showed that the maximum adsorbent capacity under optimum conditions (pH=7, 20 mg/L anthracene concentration, 0.5 g/L adsorbent dosage, and 30 min contact time) was equal to 83 mg/g. The experimental data fitted with different isotherm models showed that the equilibrium data were well described by the Langmuir model. In this study, the adsorption process overlapped more with the pseudo-second-order kinetics model. Conclusion: The obtained results indicated that the synthesized nanostructured adsorbent has a high adsorption capacity with high recovery and is efficient enough to remove anthracene from aqueous solutions.

Structural transformations of charged spherical surfactant micelles upon solubilization of water-insoluble polymer chains in salt-free aqueous solutions

2021 ◽  
pp. 118326
Author(s):  
Alexander L. Kwiatkowski ◽  
Vyacheslav S. Molchanov ◽  
Alexander I. Kuklin ◽  
Anton S. Orekhov ◽  
Natalia A. Arkharova ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Structural Transformations ◽  
Polymer Chains ◽  
Surfactant Micelles ◽  
Insoluble Polymer

The Coil-to-Globule-to-Coil Transition of Linear Polymer Chains in Dilute Aqueous Solutions: Effect of Intrachain Hydrogen Bonding

2008 ◽  
Vol 41 (22) ◽  
pp. 8927-8931 ◽  
Author(s):  
Kejin Zhou ◽  
Yijie Lu ◽  
Junfang Li ◽  
Lei Shen ◽  
Guangzhao Zhang ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Aqueous Solutions ◽  
Polymer Chains ◽  
Linear Polymer ◽  
Coil Transition ◽  
Dilute Aqueous Solutions

Inclusion behavior between molecular nanotubes and linear polymer chains in aqueous solutions

2000 ◽  
Vol 112 (9) ◽  
pp. 4321-4325 ◽  
Author(s):  
Eiji Ikeda ◽  
Yasushi Okumura ◽  
Takeshi Shimomura ◽  
Kohzo Ito ◽  
Reinosuke Hayakawa
Keyword(s):  
Aqueous Solutions ◽  
Polymer Chains ◽  
Linear Polymer

Ultrathin frozen sections of yeast without aldehyde prefixation

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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