Discontinuous carbon fiber/polyamide composites with microencapsulated paraffin for thermal energy storage

• Published in: Journal of applied polymer science 2019-04, Vol.136 (16), p.n/a
• Main Authors: Fredi, Giulia, Dorigato, Andrea, Unterberger, Seraphin, Artuso, Nicolò, Pegoretti, Alessandro
• Format: Article
• Language: English
• Subjects: Carbon fiber reinforced plastics; Crystallization; discontinuous fibers; Energy storage; Enthalpy; Materials science; microencapsulation; Modulus of elasticity; Paraffins; Phase change materials; Polyamide resins; Polymer matrix composites; Polymers; Thermal conductivity; Thermal energy; thermal energy storage; Thermal imaging; thermoplastic composites; Weight
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.47408

ABSTRACT This work focuses on the development of multifunctional thermoplastic composites with thermal energy storage capability. A polyamide 12 (PA12) matrix was filled with a phase change material (PCM), constituted by paraffin microcapsules (Tmelt = 43 °C), and reinforced with carbon fibers (CFs) of two different lengths (chopped/CF “long”[CFL] and milled/CF “short” [CFS]). DSC tests showed that the melting/crystallization enthalpy values increase with the PCM weight fraction up to 60 J/g. The enthalpy was 41–94% of the expected value and decreased with an increase in the fiber content, because the capsules were damaged by the increasing viscosity and shear stresses during compounding. Long CFs increased the elastic modulus (+316%), tensile strength (+26%), and thermal conductivity (+54%) with respect to neat PA12. Thermal imaging tests evidenced a slower cooling for the samples containing PCM, and once again the CFS‐containing samples outperformed those with CFL, due to the higher effective PCM content. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47408.