Related papers: Poroelastic indentation of mechanically confined h…
We report on the frictional behaviour of thin poly(dimethylacrylamide) (PDMA) hydrogels films grafted on glass substrates in sliding contact with a glass spherical probe. Friction experiments are carried out at various velocities and…
When a hydrophilic and deformable porous material is immersed in a bath, it may absorb the solvent and expand by several times its volume, thus forming a highly soft and porous hydrogel. A stress applied on the soft hydrogel surface deforms…
We report on the transient frictional response of contacts between a rigid spherical glass probe and a micrometer-thick poly(dimethylacrylamide) hydrogel film grafted onto a glass substrate when a lateral relative motion is applied to the…
Hydrogel consists of a crosslinked polymer matrix imbibed with a solvent such as water at volume fractions that can exceed 90\%. They are important in many scientific and engineering applications due to their tunable physiochemical…
Hydrogels are promising systems for separation applications due to their structural characteristics (i.e. hydrophilicity and porosity). In our study, we investigate the permeation of suspensions of rigid latex particles of different sizes…
We combine small angle scattering experiments and simulations to investigate the internal structure and interactions of composite Poly(N-isopropylacrylamide)-Poly(ethylene glycol) (PNIPAM-PEG) microgels. At low temperatures the…
Confined geometries offer useful and experimentally amenable mechanical testing arrangements in which to study the molecular and micro-structural processes which govern plastic yield in stress environments dominated by hydrostatic pressure…
The contact of a hydrogel during the rotational shearing on glass surface in concentrated polymer solution was observed in situ. Dynamic contact patterns that rotate in-phase with the rotational shearing of the gel were observed for the…
We report on the frictional properties of thin ($\approx \mu m$) poly(dimethylacrylamide) hydrogel films within contacts with spherical silica probes. In order to focus on the contribution to friction of interfacial dissipation, a dedicated…
We study the indentation of ultrathin elastic sheets clamped to the edge of a circular hole. This classical setup has received considerable attention lately, being used by various experimental groups as a probe to measure the surface…
Temperature-responsive properties of surface-attached poly(N-isopropylacrylamide) (PNIPAM) network films with well-controlled chemistry are investigated. The synthesis consists of cross-linking and grafting preformed ene-reactive polymer…
We report on the delamination of thin ($\approx \mu$m) hydrogel films grafted to silicon substrates under the action of swelling stresses. Poly(dimetylacrylamide) (PDMA) films are synthesized by simultaneously cross-linking and grafting…
We study the indentation of a free-standing lipid membrane suspended over a nanopore on a hydrophobic substrate by means of molecular dynamics simulations. We find that in the course of indentation, the membrane bends at the point of…
We study the indentation of a thin elastic film floating at the surface of a liquid. We focus on the onset of radial wrinkles at a threshold indentation depth and the evolution of the wrinkle pattern as indentation progresses far beyond…
In this paper we show how reliable measurements on porous ceramic films can be made by appropriate nanoindentation experiments and analysis. Room-temperature mechanical properties of the mixed-conducting perovskite material LSCF6428 were…
In fracture mechanics, polyacrylamide hydrogels have been widely used as a model material for experiments, benefited from its optical transparency, fracture brittleness, and low Rayleigh wave velocity. To describe the brittle fracture in…
We explore the effect of poly (ethylene glycol) (PEG) molar mass on the intrinsic permeability and structural characteristics of poly (ethylene glycol) diacrylate PEGDA/PEG composite hydrogel membranes. We observe that by varying the PEG…
Hyperelastic material characterization is crucial for understanding the behavior of soft materials -- such as tissues, rubbers, hydrogels, and polymers -- under quasi-static loading before failure. Traditional methods typically rely on…
An indentation testing method, which utilizes lateral contact of a long cylindrical indenter, is developed for a thin transversely isotropic incompressible elastic film deposited onto a smooth rigid substrate. It is assumed that the…
We report simulation results on melts of entangled linear polymers confined in a free-standing thin film. We study how the geometric constraints imposed by the confinement alter the entanglement state of the system compared to the…