Exploring concentration, surface area and surface chemistry effects of colloidal aggregates on fat crystal networks

Chauhan, Raamanand R.; Dullens, Roel P. A.; Velikov, Krassimir P.; Aarts, Dirk G. A. L.

doi:10.1039/c7ra01803g

Cited by 8 publications

(3 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Storage modulus speaks for the elastic portion of the material, while the loss modulus represents the dissipated energy. Both dynamic moduli are dependent on the particle–particle, particle–medium, and medium–medium interactions . As shown in Figure , adding silica NPs increased dynamic moduli in all samples, especially in the low-frequency region, signifying the contribution of the particle–particle and particle–medium interactions to the viscoelastic response of the systems.…”

Section: Resultsmentioning

confidence: 82%

“…Both dynamic moduli are dependent on the particle−particle, particle−medium, and medium−medium interactions. 29 As shown in Figure 2, adding silica NPs increased dynamic moduli in all samples, especially in the lowfrequency region, signifying the contribution of the particle− particle and particle−medium interactions to the viscoelastic response of the systems. Monodisperse polymeric liquids exhibit terminal behavior at low frequencies.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Fumed Silica-Based Suspensions for Shear Thickening Applications: A Full-Scale Rheological Study

2022

View full text Add to dashboard Cite

Understanding shear thickening fluids (STFs) is critically important in a broad spectrum of fields ranging from biology to military. STFs are referred to the suspension of solid particles in an inert carrier liquid. Customizing the thickening behavior is vital for obtaining desired properties. Hence, comprehending shear thickening mechanisms is necessary to fully understand the factors affecting the shear thickening response of the STFs. Herein, we systematically investigate the effects of a wide range of parameters, from inherent properties of the constituents, including size and surface chemistry of the suspended particles, to practical conditions such as temperature and shear history, on the shear thickening behavior of fumed silica nanoparticles (NPs)-based suspensions in a polyethylene glycol (PEG) medium. Accordingly, increasing the hydrophobicity of the silica NPs or decreasing the NP size transforms the suspensions from sol to gel. The sol systems exhibit a strong shear thickening response, while shear thinning behavior is prominent in the strong gel systems. Hybridization of different silica NPs is also leveraged to tune the shear thickening behavior. In addition, we showcase the decisive role of operating temperature or shear history on the shear thickening behavior of suspensions. For instance, in terms of the shear history, above a critical value of preshear, the shear thickening behavior occurs at lower shear rates for STFs containing hydrophilic NPs. It is believed that the provided insights in this study can pave the way for developing advanced STFs with prescribed features.

show abstract

Section: Resultsmentioning

confidence: 82%

Section: ■ Results and Discussionmentioning

confidence: 99%

Fumed Silica-Based Suspensions for Shear Thickening Applications: A Full-Scale Rheological Study

2022

View full text Add to dashboard Cite

show abstract

“…The rotary rheometer is one of the most common equipment configurations. 33,34 Testing was completed with a parallel plate rheometer (MCR 301, Anton Paar, Figure 6) under static and dynamic shear conditions with increasing angular frequency. A 20 mm diameter test geometry (PP-20) with a gap of 0.8 mm was used to ensure sufficient filling of the STF on the test disc.…”

Section: Rheological Testmentioning

confidence: 99%

Investigating the energy absorption properties of sandwich panels filled with shear thickening fluid with a weight fraction of 35% under low-velocity impact

Astaraki,

Zamani,

Pol

et al. 2023

Journal of Composite Materials

View full text Add to dashboard Cite

This research study the energy absorption performance of aluminum core honeycomb sandwich panel (ACHSP) with filled and empty cores subjected to low-velocity impact testing, with diverse skins; (i) aluminum sheets, (ii) 5-ply epoxy glass composite, and (iii) 5-ply shear thickening fluid (STF)-impregnated glass fabrics. The prepared STF was 35 wt% and the impactor heights was selected at 100 and 500 mm to assess the effect of different impact velocities on the energy absorption capability of STF. The specific energy absorption (SEA) of the STF-filled ACHSP with 5-ply STF-impregnated fabrics skin (height of 500 mm) compared to STF-filled ACHSP with aluminum sheets skin and 5-ply epoxy glass composite skin have increased by 28.38 and 21.79%, respectively. In a fact of truth, when the external force is applied to the STF-filled ACHSP, the fluid transitions from a low-velocity to a high-velocity state instantly. This transition exerts forces on the suspended particles within the fluid. Actually, during the impact, the particles come into close contact and form temporary particle networks or chains. These networks increase the viscosity of the fluid, making it resistant to flow. The energy of the impact is then absorbed by the formation and reformation of these particles’ networks. However, the SEA of STF-filled ACHSP at the height of 500 mm to empty ACHSP at the height of 100 mm have decreased significantly, and the energy absorption of STF-filled ACHSPs to corresponding empty ACHSPs have increased remarkably.

show abstract

Optimization of the Rheological Properties of Fumed‐Silica‐Based Supporting Baths for Embedded Printing and Reduction of the Effect of Crevasse Formation

Vera,

Tisato,

Nekoonam

et al. 2024

Adv Materials Technologies

View full text Add to dashboard Cite

In embedded 3D printing, the supporting gel must provide the right rheological properties to keep the ink in place. It has previously been shown that a strong and stable 3D network can be formed by particle–particle interactions of hydrophobic fumed silicas suspended in a polar solvent. Here, the rheological properties of fumed silica gels in polyethylene glycol (PEG) are investigated. The recovery properties like storage modulus, yield stress, and recovery time of the gels made of fumed silica with alkyl‐chains of different lengths are studied. A very fast recovery time (0.2 s) is achieved by increasing the length of the alkyl chains on the silica surface, leading to embedded printing results with high shape accuracy. However, with the engineered supporting gel, the formation of crevasses affects the shape of the filament. Previous approaches to reduce crevasse formation include the introduction of liquid fillers to avoid such distortions, which, however, prevents the reuse of the gels and leads to increasing waste production in embedded printing. Here, it is shown that by adjusting the rheology of the inks to fit the rheology of the supporting gel, high‐shape accuracy prints with ideally round‐shaped filaments can be achieved without the need for liquid fillers.

show abstract

Exploring concentration, surface area and surface chemistry effects of colloidal aggregates on fat crystal networks

Abstract: An investigation into the effects of concentration, surface area and surface chemistry of silica aggregates on a model fat-structured system.

Cited by 8 publications

References 13 publications

Fumed Silica-Based Suspensions for Shear Thickening Applications: A Full-Scale Rheological Study

Fumed Silica-Based Suspensions for Shear Thickening Applications: A Full-Scale Rheological Study

Investigating the energy absorption properties of sandwich panels filled with shear thickening fluid with a weight fraction of 35% under low-velocity impact

Optimization of the Rheological Properties of Fumed‐Silica‐Based Supporting Baths for Embedded Printing and Reduction of the Effect of Crevasse Formation

Contact Info

Product

Resources

About