15 research outputs found
Neutralization degree effect on viscosimetric behaviour of hydrolyzed polyacrylamide-poly(4-vinylpyridine) [AD37-P4VP] mixture in aqueous solution
cited By 7International audienceIn the present work, we describe the dependence of the 27 % hydrolyzed polyacrylamide [AD37]-poly(4-vinylpyridine) [P4VP] mixture reduced viscosity as a function of the neutralization degree of P4VP polymer, in aqueous solutions at 25 °C. Measurements are performed using the viscosimetry technique. Viscosity results showed that the polymer chains expanded at low neutralization degrees (α1). We note that the viscosity get a maximum at α≈0.86 © 2008 Springer-Verlag
Viscosimetric behaviour of hydrolyzed polyacrylamide-poly(4-vinylpyridine) [AD37-P4VP] mixture in aqueous solution
cited By 16International audienceThe interactions between 27% hydrolyzed polyacrylamide [AD37] and poly(4-vinylpyridine) [P4VP], in aqueous solutions and at neutralization degree α = 1, were studied by using viscosimetry technique. The reduced viscosities of these copolymer mixture solutions, at 25 °C, reach several orders of magnitude higher than the reduced viscosity of each polymer taken separately, and according to the ratio R of the chain numbers. Intermolecular electrostatic associations are favoured by increasing the P4VP concentration corresponding to high R values. Thus, mixtures rich in P4VP are characterized by a high decrease in the viscosity due to interpolymer complete complexation AD37-P4VP, leading to the totally contraction or collapse of the polymer chains. Strongest reduced viscosities, due to the inter-chain AD37 associations, are observed for the mixtures poor in P4VP (so the weakest ratios R of the chain numbers). In order to understand the relative effects of these two polymers on the reduced viscosity, two mixtures containing the same total quantity are compared. Reduced viscosities of each copolymer alone strongly increase by dilution of the aqueous solution. In the case of the mixture, an opposite behaviour is observed with a reduction in the reduced viscosity by dilution. So, the increase of the reduced viscosity according to AD37 concentration, at α constant, shows an intra and an inter-chain associative phenomenon. © 2006 Elsevier Ltd. All rights reserved
Polyelectrolyte complex-surfactant interactions: Effect of neutralization degree on viscometric behaviour in aqueous solution
cited By 1International audienceThe interaction between polyelectrolytes and ionic surfactants has attracted significant interest in recent years in different areas of research. In this study, the effect of the neutralization degree α on the viscosimetric behaviour of (hydrolyzed polyacrylamide, AD37-poly(4- vinylpyridine), P4VP) complex in aqueous solution and in the presence of sodium dodecyl sulphate (SDS) at T = 25 C was studied. Physicochemical results show that neutralization degree has an important effect on reduced viscosities values of (AD37-P4VP-SDS) system that reveals the electrostatic and hydrophobic interactions. Indeed, these values increase with α, and this influence is even greater for low P4VP - high AD37 concentrations systems. © 2012 Springer-Verlag
Neutralization degree effect on viscosimetric behaviour of hydrolyzed polyacrylamide-poly(4-vinylpyridine) [AD37-P4VP] mixture in aqueous solution
Conductometric study of the complex system polyelectrolyte/surfactant in aqueous solution
cited By 3International audienceIn this work, the interaction between the anionic surfactant sodium dodecyl sulfate (SDS) and the polyelectrolyte complex hydrolyzed polyacrylamide/poly(4- vinylpyridine) (AD37-P4VP) in aqueous solution was investigated by conductometric measurements. Three main series with SDS concentrations of 0.01, 0.25 and 1 % and in a wide range of P4VP and AD37 concentrations, from 0.1 × 10-4 to 4 × 10-4g/ml, and from 10 -4 to 10-3g/ml, respectively, were studied. The polyelectrolyte complex interacts strongly with the SDS surfactant. These interactions are of electrostatic and hydrophobic types. Thus, the effect of salt on the critical micelle concentration of SDS, and the neutralization degree on behavior conductivity of the mixture, were quantified. © 2012 Springer Science+Business Media B.V
Rheological behavior study of cationic surfactant-polyelectrolyte complex (AD37/P4VP-DPC) in aqueous medium
cited By 1International audiencePolyelectrolyte 27% hydrolyzed polyacrylamide-poly(4-vinylpyridine) (AD37-P4VP) complex with cationic surfactant dodecylpyridinium chloride (DPC) interactions in aqueous solution, is investigated by rheological measurements, at 20-°C with a fixed neutralization degree α-=-0.1. The results show that the interaction of complex (AD37-P4VP) is favored in the presence of the DPC where the electrostatic interactions are dominant. This interaction is governed by electrostatic and hydrophobic interactions. In the presence of salt, it is more cooperative. Three rheological behaviors are determined of this system show a shear thinning behavior, shear thickening for the strong shear rate and a newtonian behavior. Then, we determine the rheological models of the system to different concentration of P4VP in the presence and absence of salt to justify the rheological behavior of the complex.
Influence parameters in controlled adiabatic copolymerization of acrylamide/4-vinylpyridine (AM/4VP) system in aqueous media
cited By 1International audienceIn the order to offer new tools for developing structure of polymers with a high capacity of chemical modification, many series of new copolymers have been synthesized. The copolymers poly[acrylamide-co-(4-vinylpyridine)] [POLY(AM-CO-4VP)] were synthesized by radical adiabatic copolymerization of the monomers AM and 4VP in aqueous solution under several experimental conditions. Thus, different parameters such as the co-monomers composition, the water solvent percentage, and the initiator rate are studied in this work. The structure and composition of the copolymers were characterized by 1H NMR, 13C NMR, and UV-Vis spectroscopies. The molecular weights were determined by size exclusion chromatography and by viscosity. The results show that the percentage of water (solvent) influences the copolymer composition and structures. Thus, the obtained copolymers differ in their molecular weights. The reaction reactivity depends directly on the monomer 4-VP percentage in the mixture. The initiator also has an important effect and was also studied. © 2014 Springer Science+Business Media
Hydrophobic and electrostatic interactions in the mixture hydrolyzed polyacrylamide-N-dodecylpyridinium chloride (AD37-DPC) in aqueous solution
International audienceThe interactions of oppositely charged polyelectrolyte and surfactant (anionic polyacrylamide AD37 and dodecylpyridinium chloride DPC, respectively) in aqueous solution were studied at 25 C by measurement of viscosity and conductivity. The system was investigated in aqueous medium in the absence and presence of NaCl. The AD37 interacts strongly with the DPC surfactant of the opposite charge. The interactions are electrostatic and hydrophobic. Thus, they are manifested in the formation of hydrophobic aggregates. The critical aggregation concentration (CAC) is much lower than the critical micellar concentration (CMC) of the surfactant alone. However, the value of the saturation concentration X 2 is higher. The ionic strength of the medium after addition of salt explains an important part of these interactions. In fact, the electrolyte charge affects the CMC and the CAC values
Interaction between poly(4-vinylpyridine-graft-bromodecane) and textile blue basic dye by spectrophotometric study
cited By 1International audienceThe interactions between poly(4-vinylpyridine-graft-bromodecane) (P4VPBrD) and textile blue basic (TBB) dye in aqueous solution were investigated by a spectrophotometric method at room temperature, considering that the electrostatic force is the main binding force and that the color change during the combination is due to the transformation of dye species of acidic form into bound basic form as well as the bathochromic and hypsochromic effects of conjugation. The formation of an isosbestic point in the absorption spectra of textile blue basic dye species of acidic form was explained based on a new consideration about the solution equilibrium. An application based on the interaction of P4VPBrD with the basic coloring agent is presented. Tests were carried out to estimate the retention rate of the dye by P4VPBrD. © 2012 Springer Science+Business Media Dordrecht