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Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten. Multiwalled carbon nanotubes incorporated into a miscible blend of poly(phenylenether)/polystyrene - processing and characterization
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Volltext urn:nbn:de:0011-n-2546964 (1.5 MByte PDF) MD5 Fingerprint: 374c0fd1c894a78280daa00736f3c321 Erstellt am: 4.7.2014 |
| eXPRESS polymer letters 7 (2013), Nr.7, S.621-635 ISSN: 1788-618X |
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| Englisch |
| Zeitschriftenaufsatz, Elektronische Publikation |
| Fraunhofer ICT () |
Abstract
4 wt% multiwalled carbon nanotubes (MWCNTs) were incorporated into a miscible blend of polyphenylenether/ polystyrene (PPE/PS) on a twin-screw extruder at a screw speed of 600 rpm. The masterbatch obtained was diluted at 400 and 600 rpm to obtain lower MWCNT loadings in PPE/PS. Electron microscopy & optical microscopy images show very good MWCNT dispersion even at high filler loadings of 4!wt%, but slightly larger agglomerate size fractions are observable at higher screw speeds. While MWCNT addition enhanced the thermal stability of PPE/PS, a small change in glass transition was observed on the composites at different filler concentrations compared to PPE/PS. The specific heat capacity at glass transition decreases considerably until 2!wt% MWCNT and levels down thereafter for both processing conditions pointing to enhanced filler-matrix interaction at lower loadings. Storage modulus of the nanocomposites was enhanced significantly on MWCNT incorporation with reinforcing effect dropping considerably as a function of temperature, especially at lower filler contents. The modulus and the tensile strength of PPE/PS were only marginally enhanced in spite of excellent MWCNT dispersion in the matrix. Electrical percolation occurs at 0.4!wt% MWCNT content, and the electrical conductivity of 0.5!wt% MWCNT reinforced PPE/PS was close to 12 orders in magnitude higher compared to PPE/PS.