Rheology of the Pluronic P103/water system in a semidilute regime: Evidence of nonequilibrium critical behavior

Supramolecular Nanofibrillar Polymer Hydrogels

“…This gel was probably formed by entanglement of the micelles; however, the mechanism of gelation was not studied. Cylindrical micelles of the triblock copolymer poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) have also shown gel-like behavior in highly concentrated [>20 % (w/w)] solutions [172,173]. Recently, wormlike micelles have been pre-designed to act as nanofibrillar building blocks for the synthesis of hierarchically structured hydrogels.…”

Stress‐Temperature Effects on Transitions in PEO17PPO60PEO17 Triblock Copolymer Micellar Solutions

“…An explanation to this behavior is that the applied shear power that the rheometer applies to the sample is constant for t \ t ind at a given temperature; hence, it is evident that smaller mechanical shear power is required to induce the threshold of induced micellar growth as the temperature is increased. These results are due to the surfactant self-assembling induced by temperature, which is characteristic of nonionic surfactants [21] and it facilitates the increase in viscosity at earlier times. Table 2 reports the values of DE M for t ind for the several surfactant concentrations, which discloses that it deceases with increasing surfactant concentration.…”

“…This micellar growth is characterized by a dramatic increase in shear viscosity by several orders of magnitude [17,18]. Likewise, when the length of the wormlike micelles and the entanglement number density augment on increasing temperature and/or surfactant concentration, the oscillatory shear storage modulus increases rapidly because a gel-like behavior is attained [19][20][21]. The sphere-to-rod and to wormlike micellar transitions have been reported in aqueous solutions of the triblock copolymers PEO 26 P-PO 40 PEO 26 [3,[22][23][24], PEO 19 PPO 43 PEO 19 [8,17,18] and PEO 17 PPO 60 PEO 17 [15,16,21].…”

“…For PEO 17 P-PO 60 PEO 17 concentrations B20 wt% and temperatures below 27°C, micelles are spherical and grow with increasing temperature to form rod micelles [14]. These wormlike micelles exhibit strong viscoelasticity and a shear-banding region that shrinks as the cloud point is approached [21]. Recently Landazuri et al [14] have shown using light scattering that these surfactant solutions undergo a slow transition from spheres to rod like micelles upon a T-jump.…”

In situ flow visualization of capillary flow of concentrated alumina suspensions

“…Shear banding has long been studied and correlated with stress plateau (Azzouzi et al 2005;Cappelaere et al 1997;Fernández et al 2009;Hernández-Acosta et al 1999). In stress plateau region, the structural transition or coexistence of two structures was expected, which could be the origin of shear banding with nonhomogeneous flow field (Berret et al 1994;Ganapathy and Sood 2008;García-Sandoval et al 2012;Hernández-Acosta et al 1999;Holmqvist et al 2002;Miller and Rothstein 2007;Partal et al 2001;Schmitt et al 1994).…”