The dynamic rheological properties of hydroxyl-terminated polydimethyllsiloxane (PDMS) filled with calcium carbonate (CaCO
3) were investigated systematically over a broad temperature range from −40 to 50°C. The results reveal that with an increase of filler volume fraction (φ), the span of the linear viscoelastic region in which dynamic storage modulus (
G′) is constant narrows and the relaxation time of the compounds shifts to longer time scales. Beyond the critical φ (φ
c = 0.069),
G′ remarkably increases and exhibits a
"pseudo solid-like" behavior in the low frequency (ω) region, meanwhile the width and height of the modulus plateau increase with increasing φ. On the other hand, the
"Cole-Cole" plots of
G′ against dynamic loss modulus (
G″) at different temperatures indicate that the microstructure of compounds with relative high φ is distinct from those of compounds with low φ. The reasons for
"pseudo solid-like" behavior are attributed to the agglomeration of filler particles and the formation of percolated filler network structure due to filler-polymer and filler-filler interactions. When φ<φ
c, the nonhydrodynamic force of polymer matrix is predominant, while particle-particle interactions play an important role when φ>φ
c.
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