Effect of Flocculated Structure on Rheological Properties of PBT/Clay Nanocomposites

摘要

The microstructure and rheological property of poly(butylene terephthalate)/epoxy/montmorillonite nanocomposites (PCNs) were investigated. The intercalated PCNs are characterized by different techniques such as transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and rheology. It is interesting that the percolated tactoids network in the ternary hybrids becomes insensitive to the shear action with the addition of epoxy in contrast to that in the sample without epoxy, which can be attributed to the hydrogen bonds among the carbonyl groups in PBT, the hydroxyl groups in epoxy and their copolymer yielded by chain extension reactions. On the other hand, a flocculated structure of tactoids forms due to hydrogen bonding and chain extension reactions. Both the hydrogen bonds and flocculated structure have influence on the rheological behavior of the ternary hybrids remarkably, strengthening the percolated strong-associated-tactoids network and reducing the percolation threshold, while not changing the strain-scaling.