Development and thermal properties of carbon nanotube-polymer composites

The favorable conductive properties of carbon nanotubes (CNTs) offer opportunities for constructing CNT-based nanocomposites with improved thermal conduction for a range of potential applications. Such lightweight composite materials are expected to have thermal properties that depend on their CNT volume fraction and operating temperature. The lack of available CNT processing methods that are compatible with multi-laminated composite structures is one of the largest challenges facing the construction of CNT-based nanocomposites. The aim of the work is to develop enhanced thermal properties in carbon nanotube-polymer composites that can replace traditional aerospace metallic materials to reduce the weight in space structures. Dispersing the carbon nanotube onto prepreg composite structure, increases the thermal storage, increases the thermal transport and supports scientific instrumentation. The investigated composites were processed and characterized using Raman spectroscopy, thermogravimetric analysis, thermal diffusivity and differential scanning calorimetry. Through varying the concentration of single-walled carbon nanotubes (SWCNTs) up to 30 wt% to the IM7 prepreg composite, its heat capacity increased as much as 30% greater than the tested temperature range and its through-thickness thermal diffusivity increased by 30% compared to the virgin composite material. The addition of randomly oriented SWCNTs yielded an increase in the in-plane thermal conductivity ranging from 120 to 150 percent greater than the temperature range of 120–470 K and 30% in the through thickness. This may be due to interfacial resistance between the SWCNTs, the 8552 epoxy and the IM7 composite. The developed methods provide the opportunity for enhancing the thermal properties of a composite through the use of CNTs as additives. These improvements would be particularly beneficial applications such as solar arrays, fairings and thermal radiators.