Effect of microgels on the viscoelastic properties of poly(dimethylvinylsiloxanes)

The course of dynamic viscosity η′ and modulus of elasticity G′ curves versus frequency of oscillations f was compared for poly(dimethylvinylsiloxanes) (PDMVS) samples of similar weight-average molecular weights containing 0.1–0.2% by weight of microgels and free of microgels. It was found that the presence of microgels considerably changes the viscoelastic properties of PDMVS, particularly in the low-frequency range. Only for samples with microgels a linear course of the above-mentioned curves is observed. The content of microgels was determined by the light scattering method, whereas the η′ and G′ versus f values were obtained with the use of the Weissenberg rheogoniometer.