Shear-induced clustering of Brownian colloids in associative polymer networks at moderate Péclet number

Kim, Jun Tae; Helgeson, Matthew E.

doi:10.1103/physrevfluids.1.043302

Cited by 12 publications

(8 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This wide tunability of viscoelastic dynamics has led to the use of thermoresponsive transient nanoemulsion networks as a model system to study the nonlinear structure and rheology of Brownian polymer-colloid mixtures under shear flow. [112] 4.2.2. Strong attractions, low  d : Fractal gels.…”

Section: Weak Attractions: Fluid-like Clusters and Transient Networkmentioning

confidence: 98%

Colloidal behavior of nanoemulsions: Interactions, structure, and rheology

Helgeson

2016

Current Opinion in Colloid & Interface Science

Self Cite

112

View full text Add to dashboard Cite

Nanoemulsions exhibit unique behavior due to their nanoscopic dimensions, including remarkable droplet stability, interactions and rheology. These properties are significantly enhanced by nanoscopic droplet size, as well as selection of surfactant and other molecular species in solution. Electrostatic and polymer-induced interdroplet interactions are particularly powerful tools for fine-tuning the interdroplet interactions, and have led to stimuli-responsive nanoemulsion systems that provide deep insight into their unique properties. As such, nanoemulsions have emerged as powerful model systems for studying a number of colloidal phenomena including suspension rheology, repulsive and attractive colloidal glasses, aggregation processes, colloidal gelation and phase instability, and associative network formation in polymer-colloid mixtures. This review summarizes recent advances in understanding the colloidal behavior of nanoemulsions, and provides a unifying framework for understanding the various complex states that emerge, as well as perspective on emerging challenges and opportunities that will advance the use of nanoemulsions in both fundamental colloid science and technological applications. Highlights We review efforts to understand & control colloidal behavior of nanoemulsions.  Electrostatic and polymer-induced interdroplet interactions are discussed.  Repulsive interactions lead to jammed and compressed states at low volume fraction.  Attractive interactions lead to clustering, gelation and colloidal phase separation.  Nanoemulsions are model fluids to study arrested states in colloidal dispersions.

show abstract

Section: Weak Attractions: Fluid-like Clusters and Transient Networkmentioning

confidence: 98%

Colloidal behavior of nanoemulsions: Interactions, structure, and rheology

Helgeson

2016

Current Opinion in Colloid & Interface Science

Self Cite

112

View full text Add to dashboard Cite

show abstract

“…This gradual increase in viscosity over multiple cycles at low temperatures could be explained by the formation of flow-induced clusters from the Brownian relaxation of the nanoemulsions and structural relaxation of the PEGDMA matrix with respect to viscous forces. 37 Nevertheless, the printed microstructure is unlikely to be affected by the shear imposed by the build platform given the long equilibration time during the print step. The yield stress of the material does present issues if the print area is not properly refilled after the withdrawal of the build platform.…”

Section: Rheological Properties Of the Nanoemulsion Inksmentioning

confidence: 99%

3D printing of self-assembling thermoresponsive nanoemulsions into hierarchical mesostructured hydrogels

et al. 2017

View full text Add to dashboard Cite

Spinodal decomposition and phase transitions have emerged as viable methods to generate a variety of bicontinuous materials. Here, we show that when arrested phase separation is coupled to the time scales involved in three-dimensional (3D) printing processes, hydrogels with multiple length scales spanning nanometers to millimeters can be printed with high fidelity. We use an oil-in-water nanoemulsion-based ink with rheological and photoreactive properties that satisfy the requirements of stereolithographic 3D printing. This ink is thermoresponsive and consists of poly(dimethyl siloxane) droplets suspended in an aqueous phase containing the surfactant sodium dodecyl sulfate and the cross-linker poly(ethylene glycol) dimethacrylate. Control of the hydrogel microstructure can be achieved in the printing process due to the rapid structural recovery of the nanoemulsions after large strain-rate yielding, as well as the shear thinning behavior that allows the ink to conform to the build platform of the printer. Wiper operations are used to ensure even spreading of the yield stress ink on the optical window between successive print steps. Post-processing of the printed samples is used to generate mesoporous hydrogels that serve as size-selective membranes. Our work demonstrates that nanoemulsions, which belong to a class of solution-based materials with flexible functionalities, can be printed into prototypes with complex shapes using a commercially available 3D printer with a few modifications.

show abstract

“…Interestingly, during the review of this manuscript, a study was published with in vitro work done using model buffer solutions of mucins, DNA, and other biopolymers further implying that aggregation of bacteria by host-polymers can be depletion-mediated (Secor et al, 2018). In vivo, it will also be important to consider the effects of flow, as it has been shown that flow in non-Newtonian fluids can induce particle aggregation (Highgate, 1966; Michele et al, 1977; Kim and Helgeson, 2016). In particular, studies have suggested that the combination of flow and polymer elasticity can lead to aggregation (Highgate and Whorlow, 1970) and that shear thinning viscosity can influence aggregation as well (Snijkers et al, 2013).…”

Section: Discussionmentioning

confidence: 99%

High-molecular-weight polymers from dietary fiber drive aggregation of particulates in the murine small intestine

Steinberg

Datta

Naragon

et al. 2019

eLife

View full text Add to dashboard Cite

The lumen of the small intestine (SI) is filled with particulates: microbes, therapeutic particles, and food granules. The structure of this particulate suspension could impact uptake of drugs and nutrients and the function of microorganisms; however, little is understood about how this suspension is re-structured as it transits the gut. Here, we demonstrate that particles spontaneously aggregate in SI luminal fluid ex vivo. We find that mucins and immunoglobulins are not required for aggregation. Instead, aggregation can be controlled using polymers from dietary fiber in a manner that is qualitatively consistent with polymer-induced depletion interactions, which do not require specific chemical interactions. Furthermore, we find that aggregation is tunable; by feeding mice dietary fibers of different molecular weights, we can control aggregation in SI luminal fluid. This work suggests that the molecular weight and concentration of dietary polymers play an underappreciated role in shaping the physicochemical environment of the gut.Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).

show abstract

Shear-induced clustering of Brownian colloids in associative polymer networks at moderate Péclet number

Cited by 12 publications

References 50 publications

Colloidal behavior of nanoemulsions: Interactions, structure, and rheology

Colloidal behavior of nanoemulsions: Interactions, structure, and rheology

3D printing of self-assembling thermoresponsive nanoemulsions into hierarchical mesostructured hydrogels

High-molecular-weight polymers from dietary fiber drive aggregation of particulates in the murine small intestine

Contact Info

Product

Resources

About