High‐density polyethylene/expanded graphite nanocomposites produced by polymerization‐filling technique using an industrial heterogeneous catalyst |
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Authors: | Kátia Z. C da Cruz Adriana C. A. Casagrande Osvaldo L. Casagrande Jr |
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Affiliation: | 1. Centro de Inova??o e Tecnologia Braskem, Triunfo, RS, Brazil;2. Laboratory of Molecular Catalysis, Instituto de Química Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil |
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Abstract: | High‐density polyethylene nanocomposites with different expanded graphite (EG) contents (0.34–1.80 wt %) were prepared by polymerization‐filling technique using an industrial heterogeneous catalyst ( cat K ), and characterized using a range techniques: melting flow index (MFI), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and transmission electron microscopy (TEM). The MFI data showed that EG acts as a plasticizer decreasing melt viscosity in comparison to neat HDPE produced exclusively by cat K . DSC results showed that EG nucleated the HDPE crystallization as established by the increased crystallization temperature, and the degree of crystallinity. HDPE/EG nanocomposites displayed a significant improvement in the flexural (increased from 1458 to 1831 MPa), and storage modulus (increased from 122 to 1627 MPa) at only 1.80 wt % EG content. TEM images confirmed a homogeneous distribution of EG into the polymer matrix with the presence of dispersed, intercalated and aggregated EG nanofillers. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 55, 1260–1267 |
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Keywords: | expanded graphite heterogeneous catalyst high‐density polyethylene nanocomposites |
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