Stretching and polarizing a dielectric gel immersed in a solvent
This paper studies a gel formed by a network of cross-linked polymers and a species of mobile molecules. The gel is taken to be a dielectric, in which both the polymers and the mobile molecules...
View ArticleA theory of coupled diffusion and large deformation in polymeric gels
A large quantity of small molecules may migrate into a network of long polymers, causing the network to swell, forming an aggregate known as a polymeric gel. This paper formulates a theory of the...
View ArticleMechanics of Soft Active Materials (SAMs)
I have recently given seminars on Mechanics of Soft Active Materials (SAMs) at several universities, using this set of slides (pdf, 1.4 MB). I also attach the slides as ppt; please feel free to use...
View ArticleDrying-induced bifurcation in a hydrogel-actuated nanostructure
Hydrogels have enormous potential for making adaptive structures in response to diverse stimuli. In a structure demonstrated recently, for example, nanoscale rods of silicon were embedded vertically...
View ArticleInhomogeneous and anisotropic equilibrium state of a swollen hydrogel...
A polymer network can imbibe water from environment and swell to an equilibrium state. If the equilibrium is reached when the network is subject to external mechanical constraint, the deformation of...
View ArticleLarge deformation and instability in gels
I'm attaching slides of a talk that I gave yesterday at the Schlumberger-Doll Research Center. In preparing the talk, I made liberal use of slides prepared by Wei Hong for his own presentations. The...
View ArticleInhomogeneous swelling of a gel in equilibrium with a solvent and mechanical...
A network of polymers can imbibe a large quantity of a solvent and swell, resulting in a gel. The swelling process can be markedly influenced by a mechanical load and geometric constraint. When the...
View ArticleLarge deformation and electrochemistry of polyelectrolyte gels
Immersed in an ionic solution, a network of polyelectrolyte polymers imbibes the solution and swells, resulting in a polyelectrolyte gel. The swelling is reversible, and is regulated by ionic...
View ArticleFormation of creases on the surfaces of elastomers and gels
When a block of an elastomer is bent, the compressed surface may form a crease. This paper analyzes the critical condition for creasing by comparing the elastic energy in a creased body and that in a...
View ArticleA theory of constrained swelling of a pH-sensitive hydrogel
Many engineering devices and natural phenomena involve gels that swell under the constraint of hard materials. The constraint causes a field of stress in a gel, and often makes the swelling...
View ArticleUsing indentation to characterize the poroelasticity of gels
When an indenter is pressed into a gel to a fixed depth, the solvent in the gel migrates, and the force on the indenter relaxes. Within the theory of poroelasticity, the force relaxation curves for...
View ArticleIndentation of polydimethylsiloxane submerged in organic solvents
This paper uses a method based on indentation to characterize a polydimethylsiloxane (PDMS) elastomer submerged in an organic solvent (decane, heptane, pentane, or cyclohexane). An indenter is pressed...
View ArticlePoroelasticity of a covalently crosslinked alginate hydrogel under compression
This paper studies the poroelastic behavior of an alginate hydrogel by a combination of theory and experiment. The gel—covalently crosslinked, submerged in water and fully swollen—is suddenly...
View ArticleA Theory of Ionic Polymer Conductor Network Composite
Ionic polymer conductor network composite (IPCNC) is a mixed conductor consisting of a network of loaded ionomer and another network of metallic particles. It is known that the microstructure of the...
View ArticleIndentation: a simple, nondestructive method for characterizing the...
We use instrumented indentation to characterize the mechanical and transport behavior of a pH-sensitive hydrogel in various aqueous buffer solutions. In the measurement an indenter is pressed to a...
View ArticlePoroelastic relaxation indentation of thin layers of gels
We develop a method of poroelastic relaxation indentation (PRI) to characterize thin layers of gels. The solution to the time-dependent boundary-value problem is obtained in a remarkably simple form,...
View ArticleSymposium on Soft Materials and Structures at 49th SES Meeting (Abstract...
Dear Colleagues, We would like to to draw your attention to the Symposium on **Soft Materials and Structures** to take place at the upcoming 49th Meeting of the Society of Engineering Sciences (SES) at...
View Articleviscoelasticity and poroelasticity in elastomeric gels
An elastomeric gel is a mixture of a polymer network and a solvent. In response to changes in mechanical forces and in the chemical potential of the solvent in the environment, the gel evolves by two...
View ArticleJournal Club Theme of September 2012: Fracture of polymeric gels
A polymeric gel consists of a polymer network swollen by small solvent molecules. It could be synthesized from a monomer solution through gelation or from a dry elastomer directly through swelling....
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