Synthesis and Characterization of Chiral [3,22]‐Ionenes

Bazito, Reinaldo C.; Cássio, Fernando; Quina, Frank H.

doi:10.1002/masy.200551124

Cited by 10 publications

(7 citation statements)

References 22 publications

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“…10,11 Conductivity measurements were performed at 25 ± 0.1ºC under nitrogen atmosphere using a CDM-85 Radiometer Research Conductimeter with a conductivity cell of bright platinum electrodes with 1.295 cm -1 cell constant. All conductivity measurements were highly reproducible and it were performed at least three times.…”

Section: Methodsmentioning

confidence: 99%

Intermolecular Association of Amphipathic Polyelectrolytes in Aqueous Solutions

Rı́os

Urzúa

Villalobos

et al. 2016

J. Chil. Chem. Soc.

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The intermolecular association of amphipathic polyelectrolytes is studied using fluorescence and conductivity methods. This type of interaction is evidenced by the decrease in the average distances between charges as the polyelectrolyte side chain increases in length. This modify the dissociation degree and consequently, the linear charge density parameter. These distances were calculated with the Manning counterion condensation theory for the conductivity of polyelectrolyte solutions. The determination of the ratio I 1 /I 3 of the fluorescence bands of pyrene with polymer content reveals the formation of hydrophobic microdomains at very low concentrations, smaller than the required concentration to produce a significant change in the average distances between charges. These distances and also the I 1 /I 3 ratio vary with polymer concentration and their values were dependent on the size of the side chain in the polyelectrolyte. Finally, the experimental behavior of the solution viscosity and electrical conductivity of polyelectrolytes, which increase drastically with dilution, can be explained as a continuous change in the average distances between charges which produce conformational changes.

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Section: Methodsmentioning

confidence: 99%

Intermolecular Association of Amphipathic Polyelectrolytes in Aqueous Solutions

Rı́os

Urzúa

Villalobos

et al. 2016

J. Chil. Chem. Soc.

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“…[6,7] The synthesis of the PC8-PC12 polyelectrolytes is summarized in the reactions shown in Fig. 1.…”

Section: Methodsmentioning

confidence: 99%

Binding of Phenols with Amphipathic Cationic Polyelectrolytes

Rı́os

Collío

Urzúa

et al. 2014

Journal of Macromolecular Science, Part B

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The association of phenols, such as p-cresol, tribromophenol, and trichlorophenol, with several amphipathic poly (n-alkylmethyldiallylammonium) chlorides in aqueous solution was studied by ultrafiltration. The n-alkyl residues were octyl, decyl, and dodecyl and the binding degrees were significantly higher than those found with the hydrophilic poly (diallyldimethylammonium) chloride. The results agreed well with the Satake and Yang's treatment and Hill's empirical equation for the association process, thereby revealing, in both cases, an increasing cooperative effect as the polyelectrolyte side chain increased in length for the same phenol, and when the hydrophobic nature of the phenol increased for the same kind of polyelectrolyte. From the phenomenological association constants, the estimated molar standard free energies of association ranged from −19 kJmol −1 , for the more hydrophilic phenoxide-polyelectrolyte pair, to −28 kJmol −1 for the more hydrophobic pairs. The main result is that the amphipathic nature of these polyelectrolytes makes them efficient systems to trap anionic contaminants, better than hydrophilic flocculants.

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“…[1] The [3,6]-ionene utilized was commercial hexadimethrine bromide (Aldrich). Immobilization required basically three steps: The first step is selective demethylation of the [3,m]-ionene, transforming it into a tertiary polyamine, [11] as described previously. [11] The second step is the covalent coupling of the tertiary polyamine onto chloropropyl-bonded silica.…”

Section: Methodsmentioning

confidence: 99%

“…Immobilization required basically three steps: The first step is selective demethylation of the [3,m]-ionene, transforming it into a tertiary polyamine, [11] as described previously. [11] The second step is the covalent coupling of the tertiary polyamine onto chloropropyl-bonded silica. 3-Chloropropylated silica (Aldrich, 230-400 mesh, 3.5g) was added to an acetonitrile solution (30 mL) of tertiary polyamine derived from either [3,6]-ionene (504 mg of polyamine) or the [3,22]-ionene (690 mg of polyamine).…”

Section: Methodsmentioning

confidence: 99%