Polymer Gel near the Sol-Gel Transition.

Dynamical transition of heat transport in a physical gel near the sol-gel transition

We experimentally study heat transport in a gelatin solution near a reversible sol-gel transition point where viscosity strongly depends on temperature. We visualize the temperature field and velocity field using thermochromic liquid crystals and polystyrene latex particles, respectively. During the initial stages of heating, we find that heat transport undergoes a dynamical transition from con...

Entropic Elasticity at the Sol-Gel Transition

The sol-gel transition is studied in two purely entropic models consisting of hard spheres in continuous three-dimensional space, with a fraction p of nearest neighbor spheres tethered by inextensible bonds. When all the tethers are present (p = 1) the two systems have connectivities of simple cubic and face-centered cubic lattices. For all p above the percolation threshold pc, the elasticity h...

Flow birefringence at the sol-gel transition

2014 The information provided by a flow birefringence experiment at the sol-gel transition in the sol phase is discussed There are two competing effects : cluster rotations, and cluster elastic deformation. In a steady state, rotational effects turn out to be dominant. For small velocity gradients S we predict an extinction angle x such that 03C0/4 x diverges with an exponent roughly equal to 3...

Viscoelastic Properties for Sol-Gel Transition

Two Simple Approaches to Sol-Gel Transition

We represent a theory of polymer gelation as an analogue of liquid-glass transition in which elastic fields of stress and strain shear components appear spontaneously as a consequence of the cross-linking of macromolecules. This circumstance is explained on the basis of obvious combinatoric arguments as well as a synergetic Lorenz system, where the strain acts as an order parameter, a conjugate...