Effect of nano-silica filler on the rheological and morphological properties of polypropylene/liquid-crystalline polymer blends

47Citations
Citations of this article
24Readers
Mendeley users who have this article in their library.
Get full text

Abstract

A fumed hydrophilic nano-silica-filled polypropylene (PP) composite was blended with a liquid-crystalline polymer (LCP; Rodrun LC5000). The preblended polymer blend was extruded through a capillary die; this was followed by a series of rheological and morphological characterizations. The viscosity of the PP matrix increased with the addition of the hydrophilic nano-silica. At shear rates between 50 and 200 s-1, the composite displays marked shear-thinning characteristics. However, the incorporation of LC5000 in the PP composite eliminated the shear-thinning characteristic, which suggests that LC5000 destroyed the agglomerated nano-silica network in the PP matrix. Although the viscosity ratio of LCP/PP was reduced after the addition of nano-silica fillers, the LCP phases existed as droplets and ellipsoids. The nano-silicas were concentrated in the LC5000 phase, which hindered the formation of LCP fibers when processed at high shear deformation. We carried out surface modification of the hydrophilic nano-silica to investigate the effect of modified nano-silica (M-silica) on the morphology of the PP/LC5000 blend system. Ethanol was successfully grafted onto the nano-silica surface with a controlled grafting ratio. The viscosity was reduced for PP filled with ethanol-M-silica when compared to the system filled with untreated hydrophilic nano-silica. The LC5000 in the (PP/M-silica)/LC5000 blend existed mainly in the form of fibrils. At high shear rates (e.g., 3000 s-1), the LC5000 fibril network was formed at the skin region of the extrudates. The exclusion of nano-silica in the LC5000 phase and the increased viscosity of the matrix were responsible for the morphological changes of the LCP phase. © 2002 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 87.

Cite

CITATION STYLE

APA

Zhang, L., Tam, K. C., Gan, L. H., Yue, C. Y., Lam, Y. C., & Hu, X. (2003). Effect of nano-silica filler on the rheological and morphological properties of polypropylene/liquid-crystalline polymer blends. Journal of Applied Polymer Science, 87(9), 1484–1492. https://doi.org/10.1002/app.11513

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free