SYNTHESIS OF CRITICALLY CROSS-LINKED MICROGELS BY DISPERSION POLYMERIZATION

Microgels with cross-link densities close to the critical value of gel transition are synthesized via polymerization in microemulsion stabilized with a polymeric surfactant. The resulting structures are characterized by static and dynamic light scattering, viscometry, small angle neutron scattering and dynamic-mechanical shear experiments. The proximity of the gel point influences the different properties in a different way. Global properties such as particle shape are closely connected with the gel point whereas the local structure and relaxation show critical behavior even quite far from the gel point.