Effect of polymer–surfactant interactions on elongational viscosity and atomization of peo solutions

The effects of chain conformation in the microfluidic entry flow of polymer–surfactant systems

“…While there is a discrepancy between the values of Á ext,dD/dt and Á ext,fit , the order of magnitude is the same and the important qualitative observation of increasing apparent extensional viscosity with the addition of SDS is consistent. Furthermore, both the trend and order of magnitude for the extensional viscosities have been confirmed by previous studies using opposed jet rheometers, more suited to extremely dilute polymeric solutions [7,11]. For the purpose of clarification and because the values are used in later quantitative analysis of the Weissenberg number, it should be noted that the extensional relaxation times reported in Table 1, CaBER , were not obtained from the aforementioned functional form.…”

“…Small angle neutron scattering (SANS) has been used to show that a PEO coil saturated with SDS micelles is swollen compared to a free coil in a good solvent, taking on a cage-like structure rather than a fully-stretched "necklace" [10]. Furthermore, an opposing jet elongational rheometer has been used to observe an abrupt rise in elongational viscosity at critical values of strain rate, and varying with SDS concentration [11]. These studies have clearly shown the transition of PEO from flexible chain to semi-rigid behaviour as SDS aggregates form along the polymer backbone.…”

Rheological characterization of poly(ethylene oxide) solutions of different molecular weights

“…It is the case of waterbased drilling fluids, where polymers are used not only to reduce filtration but also as stabilizing agent, emulsifier and lubricant. They are also used to modify the break up of liquids into droplets in jet printing, automotive painting, spraying of agricultural chemicals, and control of machining fluid misting [2]. Since the rheological properties of polymer solutions are strongly related to the chemical formulation, the molecular weight and the concentration of the polymer, the solvent properties and external variables such as the temperature and the pressure [3], understanding the relationship between the microstructure of the polymer solutions and their macroscopic properties is of fundamental importance.…”

Investigation on the Interactions of Poly(ethylene oxide) and Ionic Liquid 1-Butyl-3-methyl-imidazolium Bromide by Viscosity and Spectroscopy

“…In this equation, the thermodynamic parameters Ψ, κ, and θ are the entropy of dilution parameter, the heat of dilution parameter, and theta temperature, respectively. The polymer− solvent interaction parameter, χ, can be expressed in terms of entropy and heat of dilution parameter as 16 χ κ = + − Ψ 0.5 (6) In Newtonian fluids the temperature dependence of the viscosity is usually expressed in the form of the Arrhenius relationship: 23,24 η = A e E RT / v (7) where E v the activation energy, A is pre-exponential factor, R the gas constant, and T the temperature in K. Viscosity− temperature data are on the basis of the above equations, usually presented in the form of Lnη as a function of reciprocal temperature (1/T). The flow activation energy and preexponential factor are determined from the slope and intercept of these diagrams.…”

“…Poly­(ethylene oxide) (PEO), a linear and nontoxic homopolymer, is water-soluble due to hydrogen bonding with ethylene oxide groups. , In this paper, the thermodynamic quality of a solvent at different temperatures was investigated using a viscometric method. The thermodynamic quality of solvent is a measure of interaction between solvent and solute, and in turn the interaction is related to the Hildebrand solubility parameter .…”