Sol-Gel Transition of Branched Low Density Polyethylene in Organic Solvents

Low-density nanoporous iron foams synthesized by sol-gel autocombustion

Nanoporous iron metal foams were synthesized by an improved sol-gel autocombustion method in this report. It has been confirmed to be pure phase iron by X-ray diffraction measurements. The nanoporous characteristics were illustrated through scanning electron microscope and transmission electron microscope images. Very low density and quite large saturation magnetization has been performed in th...

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...

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...