Rheological studies on sterically stabilized model dispersions of uniform colloidal spheres

Choi, Gwan-Young; Krieger, Irvin M.

doi:10.1016/0021-9797(86)90210-9

Cited by 138 publications

(62 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As for the particles used, there are several examples in literature of the different materials that can be employed, such as CaCO 3 [20], PMMA [21,22], PVC [23], PS and SiO 2 [6,13,20]. For our purposes, different solutions were produced using two types of commercially available SiO 2 with average diameters of 7 and 14 nm (Sigma Aldrich).…”

Section: Theoretical Aspectsmentioning

confidence: 99%

Design and Manufacturing of a Novel Shear Thickening Fluid Composite (STFC) with Enhanced out-of-Plane Properties and Damage Suppression

Pinto

Meo

2016

Appl Compos Mater

View full text Add to dashboard Cite

The ability to absorb a large amount of energy during an impact event without generating critical damages represents a key feature of new generation composite systems. Indeed, the intrinsic layered nature of composite materials allows the embodiment of specific hybrid plies within the stacking sequence that can be exploited to increase impact resistance and damping of the entire structure without dramatic weight increase. This work is based on the development of an impact-resistant hybrid composite obtained by including a thin layer of Non-Newtonian silica based fluid in a carbon fibres reinforced polymer (CFRP) laminate. This hybrid phase is able to respond to an external solicitation by activating an order-disorder transition that thickens the fluid increasing its viscosity, hence dissipating the energy impact without any critical failure. Several Shear Thickening Fluids (STFs) were manufactured by changing the dimensions of the particles that constitute the disperse phase and their concentrations into the continuous phase. The dynamic viscosity of the different STFs was evaluated via rheometric tests, observing both shear thinning and shear thickening effects depending on the concentration of silica particles. The solutions were then embedded as an active layer within the stacking sequence to manufacture the hybrid CFRP laminates with different embedded STFs. Free vibration tests were carried out in order to assess the damping properties of the different laminates, while low velocity impact tests were used to evaluate their impact properties. Results indicate that the presence of the non-Newtonian fluid is able to absorb up to 45 % of the energy during an impact event for impacts at 2.5 m/s depending on the different concentrations and particles dimensions. These results were confirmed via C-Scan analyses to assess the extent of the internal delamination.

show abstract

Section: Theoretical Aspectsmentioning

confidence: 99%

Design and Manufacturing of a Novel Shear Thickening Fluid Composite (STFC) with Enhanced out-of-Plane Properties and Damage Suppression

Pinto

Meo

2016

Appl Compos Mater

View full text Add to dashboard Cite

show abstract

“…[ 2 ] and [ 3 ] correspond to constant surface potential and constant surface charge, respectively. Several improvements can be made on the theory for G~.…”

Section: R = 2a(074/4) 1/3 the + And -Signs Inmentioning

confidence: 99%

“…Concentrated dispersions display a number of interesting rheological phenomena, examples of which are shear thinning ( 1,2), shear thickening (3-7), thixotropy (8), and yield stress (9). Most investigations of these concentrated dispersions involved the steady shear properties, because of lack of sophisticated rheological measuring instruments.…”

Section: Introductionmentioning

confidence: 99%

Viscoelastic properties of concentrated shear-thickening dispersions

Boersma

Lavèn

Stein

1992

Journal of Colloid and Interface Science

119

View full text Add to dashboard Cite

The viscoelastic properties of electrostatically stabilized concentrated dispersions of silica and of glass particles in a glycerol/water mixture are studied by oscillatory shear measurements. These dispersions are shear-thickening in steady shear flow. At most frequencies the loss modulus is found to dominate the storage modulus. At certain critical combinations of deformation amplitude and frequency the response signal becomes distorted, containing higher harmonics. This phenomenon can be ascribed to flow blockage, closely related to shear thickening in steady shear flow. When plotting the critical deformation against the frequency, three different regions can be detected. At low frequencies there is the steady shear flow limit, at intermediate frequencies double-layer overlap causes nonlinearity in the response signal, and at high frequencies there is a region where the critical deformation for flow blockage is a system-dependent function of the frequency, but is independent of the volume fraction. The magnitudes of the storage moduli are found to be in reasonable agreement with theoretical predictions.

show abstract

“…Several researchers have claimed that the primary fundamental mechanism for reinforcement and non-linear behavior appears to be the filler-matrix interactions, but not filler agglomerations (Osman and Atallah, 2006). In addition, micromechanical simulations predict that the viscoelastic and mechanical properties of PCMs do not depend on the size of particles (Barnes et al, 1989;Choi and Krieger, 1986). Nevertheless, there exist contradictions in the literature data and results, and the consequences of circular micro-inclusions on the viscoelasticity are still debatable (Cai and Salovey, 1999;Vollenberg and Heikens, 1989 To have a fundamental understanding on the effects of the presence of particles and their properties on the overall response of composites, various micromechanical models have been formulated (Nemat-Nasser and Hori, 1999).…”

Section: Introductionmentioning

confidence: 99%

Microstructure-Based Computational Modeling of Mechanical Behavior of Polymer Micro/Nano Composites

Tehrani¹

2013

View full text Add to dashboard Cite

The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Lightweight advanced materials are critical in the manufacturing of many Army vehicles. Recently, numerical tools have been utilized to customize experiments to achieve optimized behavior of micro/nano polymer composites (MNPCs). Most numerical studies are based on characterizing the MNPCs through simple microstructures, as circular particles or straight fibers embedded in a specific polymer matrix. Although these geometries are effective in virtually modeling some types of composite material behavior, they fail to address some critical key Names of Under Graduate students supportedPERCENT_SUPPORTED NAME FTE Equivalent:Total Number:The number of undergraduates funded by this agreement who graduated during this period with a degree in science, mathematics, engineering, or technology fields:The number of undergraduates funded by your agreement who graduated during this period and will continue to pursue a graduate or Ph.D. degree in science, mathematics, engineering, or technology fields:Number of graduating undergraduates who achieved a 3.5 GPA to 4.0 (4.0 max scale): Number of graduating undergraduates funded by a DoD funded Center of Excellence grant for Education, Research and Engineering:The number of undergraduates funded by your agreement who graduated during this period and intend to work for the Department of DefenseThe number of undergraduates funded by your agreement who graduated during this period and will receive scholarships or fellowships for further studies in science, mathematics, engineering or technology fields: Student Metrics This section only applies to graduating undergraduates supported by this agreement in this reporting periodThe number of undergraduates funded by this agreement who graduated during this period: 0.00 ...... Names of Personnel receiving masters degrees Inventions (DD882) Scientific ProgressBecause the mechanical responses of polymers and many types of polymer composites are in the large deformation range, the Eulerian or Lagrangian concept is required for measuring the stress and strain. On the other hand, developing a large deformation based constitutive model requires a number of considerations, and should be performed from a thermodynamics point of view to study the motion of each component of the material. Even though such approach is precise and physically sound, it is limited to just one type of material. Furthermore, polymers show high dependency to the rate and time of the applied load; hence, employing viscoelastic, viscoplastic and viscodamage models is necessary. To address these issues, a consistent framework is developed to generalize elastic/viscoelastic and plastic/viscoplastic models from small strain to the large deformation range. The developed continuum based app...

show abstract

Rheological studies on sterically stabilized model dispersions of uniform colloidal spheres

Cited by 138 publications

References 7 publications

Design and Manufacturing of a Novel Shear Thickening Fluid Composite (STFC) with Enhanced out-of-Plane Properties and Damage Suppression

Design and Manufacturing of a Novel Shear Thickening Fluid Composite (STFC) with Enhanced out-of-Plane Properties and Damage Suppression

Viscoelastic properties of concentrated shear-thickening dispersions

Microstructure-Based Computational Modeling of Mechanical Behavior of Polymer Micro/Nano Composites

Contact Info

Product

Resources

About