Density and Viscosity of Binary and Ternary Mixtures of Poly(ethylene glycol) and Poly(acrylic acid, sodium salt) at Temperatures of (288.15 to 318.15) K (original) (raw)
Related papers
Journal of Chemical & Engineering Data, 2005
The densities and viscosities of binary and ternary solutions of the aqueous two-phase systems created by the polyethylene glycol 6000 + triammonium citrate + water system were measured at different temperatures [(25, 30, 35, 40, and 45)°C] and correlated with empirical equations. The density data were compared with those available in the literature. The density data show a linear variation with the mass fraction of the polymer for all temperatures. The density and viscosity of the top and bottom phases were also measured and reported.
Density and Viscosity of Concentrated Aqueous Solutions of Polyethylene Glycol
Journal of Chemical and Engineering Data, 1994
The densities and viscosities of concentrated aqueous solutions of polyethylene glycol (10-50 mass %) have been measured. The polyethylene glycol samples had average molecular masses of 8000,3350, and 1000. The values of the density from 277 to 298 K show a linear variation with the polyethylene glycol concentration and differ, at most, by 10.07% from those of pure water at the same temperature. In order to estimate the values of dynamic viscosity, an equation is proposed which takes into account the influence of the polyethylene glycol concentration and the temperature in the range 277-313 K. The viscosity of mixtures of polyethylene glycol + magnesium sulfate + water were also studied. A linear relationship exists between the viscosities of the aqueous solutions of polyethylene glycol and the concentration of magnesium sulfate.
The present work is part of a broader study devoted to the application of aqueous two-phase systems (ATPSs) for in situ separation of low molar mass organic acids in the biotechnology industry. The ATPSs studied comprise poly(ethyleneglycol) (PEG) and poly(ethyleneimine) PEI. The PEG average molar mass was 4000 gmol -1 with a polydispersity index of 1.05, and the PEI molar mass was 25000 gmol -1 with a polydispersity index of about 2.5. Measurements of the binodal curves of the ATPSs were performed at T = (25 and 36) 0 C, p = 1 bar, 5 ≤ pH ≤ 9 and at two different concentrations of lactic acid. The partition coefficient of the lactic acid was also measured at T = 36 0 C and pH = 7.5.
Densities and Viscosities of Polyethylene Glycol 6000+ Triammonium Citrate+ Water Systems
Journal of Chemical …, 2009
The densities and viscosities of binary and ternary solutions of the aqueous two-phase systems created by the polyethylene glycol 6000 + triammonium citrate + water system were measured at different temperatures [(25, 30, 35, 40, and 45)°C] and correlated with empirical equations. The density data were compared with those available in the literature. The density data show a linear variation with the mass fraction of the polymer for all temperatures. The density and viscosity of the top and bottom phases were also measured and reported.
Biochemical Engineering Journal, 2009
In this paper, which forms part of a study on aqueous two-phase systems (ATPS) for separation of lowmolar-mass organic acids in the biotechnology industry, we examine the phase behaviour of ATPSs containing poly(ethylene glycol) (PEG) and poly(ethyleneimine) (PEI) as a function of pH, the nature of the acid used for titrating PEI, and the addition of lactic acid. We show that increasing the pH leads to contraction of the two-phase regions and that titrating PEI with a higher polyvalent acid results in a larger two-phase region. We propose a mechanism explaining the experimentally observed phase behaviour. Finally, we demonstrate that the lactic acid partition coefficient is very favourable (the acid partitions preferentially to the PEI-rich phase), which confirms that the (PEG + PEI) ATPSs could be used to advantage as a medium for lactic acid bio-transformation.
The Journal of Chemical Thermodynamics, 2008
New experimental (liquid + liquid) equilibrium data have been determined for aqueous systems containing poly(ethylene glycol) of nominal molar mass 10,000 and magnesium sulphate at T = (295.15, 301.15, 305.15, and 311.15) K. The effect of temperature on the liquid compositions of coexisting phases is discussed. The experimental (liquid + liquid) equilibrium data of the systems were correlated by non-random two-liquid (NRTL) activity coefficient model. The interaction parameters of the NRTL activity coefficient model are obtained and reported. The calculated root mean square deviations (RMSD) showed that NRTL activity coefficient model can be used satisfactorily to correlate the (liquid + liquid) equilibrium data in aqueous solution of the {poly(ethylene glycol) + magnesium sulphate} system.
2016
Aqueous two-phase systems consisting of polyethylene glycol (PEG), sodium polyacrylate (NaPAA), and a salt have been studied. The effects of the polymer size, salt type (NaCl, Na 2 SO 4 , sodium adipate and sodium azelate) and salt concentrations on the position of the binodal curve were investigated. The investigated PEG molecules had a molar mass of 2,000 to 8,000 g/mol, while that of NaPAA was 8,000 g/mol. Experimental phase diagrams, and tie lines and calculated phase diagrams, based on Flory-Huggins theory of polymer solutions are presented. Due to strong enthalpic and entropic balancing forces, the hydrophobicity of the added salt has a strong influence on the position of the binodal, which could be reproduced by model calculations.
Phase Diagrams of the Aqueous Two-Phase Systems of Poly(ethylene glycol)/Sodium Polyacrylate/Salts
Polymers, 2011
Aqueous two-phase systems consisting of polyethylene glycol (PEG), sodium polyacrylate (NaPAA), and a salt have been studied. The effects of the polymer size, salt type (NaCl, Na 2 SO 4 , sodium adipate and sodium azelate) and salt concentrations on the position of the binodal curve were investigated. The investigated PEG molecules had a molar mass of 2,000 to 8,000 g/mol, while that of NaPAA was 8,000 g/mol. Experimental phase diagrams, and tie lines and calculated phase diagrams, based on Flory-Huggins theory of polymer solutions are presented. Due to strong enthalpic and entropic balancing forces, the hydrophobicity of the added salt has a strong influence on the position of the binodal, which could be reproduced by model calculations.
Fluid Phase Equilibria, 1995
Experimental results for some properties (activity of water, change of enthalpy on mixing and diluting, compositions of coexisting liquid phases) of aqueous solutions of hydrophilic polymers poly(ethylene glycol) and dextran between 277 and 333 K are reported• The results are used to develop and test a semiempirical group contribution expression for the excess Gibbs energy of diluted aqueous polymer solutions. The model is applied to correlate some of the new experimental data, while the remaining experimental results are used to test its potential for predicting the influence of polymer molecular weight and temperature on the phase behavior of aqueous two-phase systems-a field where most previously known methods fail.