| 초록 |
The polymer layered silicate nanocomposite has been prepared by simple melt mixing of three components, i.e., polypropylene (PP), maleic anhydride modified polypropylene (MAPP), and organically modified clay. The dispersibility of clay layers was investigated by X-ray diffractometer. The nanocomposite exhibits higher thermal stability compared to that of unfilled polymer. The rheology of nanocomposite is also investigated using steady and oscillatory shear tests. As compared to pure polypropylene, the nanocomposites show increased steady shear viscosity. Besides, the onset of nonlinearty (shear thinning) occurs at lower deformation rates than those with unfilled polymer, which implies that clay modifies the relaxation process of polymer. The storage (G’) and loss (G’’) moduli increase with increasing clay loading at all frequencies. However, the power law dependence of G’ and G’’ in the terminal zone is different from that observed in homopolymers and decreases with increasing clay loading. Similarities of the rheological response of the nanocomposite and block copolymer and liquid crystalline polymer are also introduced.
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