Characterization of multi-walled carbon nanotube/phenylethynyl terminated polyimide composites

Multi-walled carbon nanotubes (MW-CNTs) were dispersed throughout a thermosetting polyimide Triple A PI (TriA-PI). TriA-PI is a newly developed phenylethynyl terminated polyimide, and exhibits excellent mechanical properties and processability with high glass transition temperature (Tg > 300 degreesC). The resulting composites containing 3.3, 7.7, 14.3 wt% MW-CNT exhibited relatively good dispersion in macroscopic scale. Tensile tests on the composites showed an increase in the elastic modulus and the yield strength, and decrease in the failure strain. Dynamic mechanical analysis (DMA) showed an increase in the glass transition temperature with incorporation of the carbon nanotubes. The experimental results suggested that the carbon nanotubes are acting as macroscopic crosslinks, and are further immobilizing the polyimide chains at elevated temperature. (C) 2004 Elsevier Ltd. All rights reserved.