Dynamic Light Scattering Study on Particle Diffusion in Slide-Ring Gels: Enhanced Fluctuation of Sliding Networks

Abstract

In slide-ring (SR) gels, polymer chains are cross-linked by rings and can slide through the cross-linking points. The high chain mobility in SR gels is responsible for their unique physical properties such as softness, high deformability, and crack resistance. In this study, the dynamics of the polymer network in SR gels was investigated by the microrheological technique. The diffusion coefficients of the silica nanoparticles in SR gels with different cross-linking densities were measured by dynamic light scattering (DLS). It was found that the diffusion coefficient of the probe particles in the SR gels does not decrease monotonically with increasing cross-linking density even though their mesh sizes are close to the particle size. This suggests that the slidability of the cross-linking points enhances fluctuation of the polymer networks in the SR gels.