Melt rheology of polylactide/montmorillonite nanocomposites
Abstract
In this article, the linear and nonlinear shear rheological behaviors of polylactide (PLA)/clay (organophilic-montmorillonite) nanocomposites (PLACNs) were investigated by an Advanced Rheology Expanded System rheometer. The nanocomposites were prepared by master batch method using a twin-screw extruder with poly(ε-caprolactone) (PCL) as a compatibilizer. The presence of org-MMT leads to obvious pseudo-solid-like behaviors of nanocomposite melts. The behaviors caused by the formation of a "percolating network" derived from the reciprocity among the strong related sheet particles. Therefore, the storage moduli, loss moduli, and dynamic viscosities of PLACNs show a monotonic increase with MMT content. Nonterminal behaviors exists in PLACNs nanocomposites. Besides the PLACNs melts show a greater shear thinning tendency than pure PLA melt because of the preferential orientation of the MMT layers. Therefore, PLACNs have higher moduli but better processibility compared with pure PLA.
- Publication:
-
Journal of Polymer Science B Polymer Physics
- Pub Date:
- December 2007
- DOI:
- 10.1002/polb.21317
- Bibcode:
- 2007JPoSB..45.3189G