Crystal growth in alumina/poly(ethylene terephthalate) nanocomposite films

Abstract

The crystal growth and morphology in 150-nm-thick PET nanocomposite thin films with alumina (Al 2 O 3 ) nanoparticle fillers (38 nm size) were investigated for nanoparticle loadings from 0 to 5 wt %. Transmission electron microscopy of the films showed that at 1 wt % Al 2 O 3 , the nanoparticles were well dispersed in the film and the average size was close to the reported 38 nm. Above 2 wt % Al 2 O 3 , the nanoparticles started to agglomerate. The crystal growth and morphological evolution in the PET nanocomposite films kept at an isothermal temperature of 217 8C were monitored as a function of the holding time using in situ atomic force microscopy. It was found that the crystal nucleation and growth of PET was strongly dependent on the dispersed particles in the films. At 1 wt % Al 2 O 3 , the overall crystal growth rate of PET lamellae was slower than that of the PET homopolymer films. Above 2 wt % Al 2 O 3 , the crystal growth rate increased with nanoparticle loading because of heterogeneous nucleation. In addition, in these PET nanocomposite thin films, the Al 2 O 3 nanoparticles induced preferentially oriented edge-on lamellae with respect to the surface, which was not the case in unfilled PET as determined by grazing-incidence X-ray diffraction. V V C 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 747-757, 2007

Mechanistic Studies in Friction and Wear of Bulk Materials

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Confined crystallization of nanolayered poly(ethylene terephthalate) using X-ray diffraction methods

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Gas permeability, solubility and diffusivity in 1,2-polybutadiene containing brookite nanoparticles

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