Novel reactive thermoplastic resin as a matrix for laminates containing phase change microcapsules

This work aims at developing multifunctional thermoplastic laminates combining structural and heat storage/management functions. The laminates are constituted by paraffin microcapsules as phase change materials (PCM), continuous carbon fibers, and a novel thermoplastic liquid methyl methacrylate resin (Elium), processable as a thermoset. The characterization aims to study how the paraffin microcapsules influence the thermo-mechanical properties and thermal management performance of Elium and of the relative composite laminates. For the Elium/PCM systems, the phase change enthalpy increased with the experimental PCM concentration up to 101 J/g, but the mechanical properties decreased concurrently. The melting enthalpy of the laminates also increased with the microcapsule amount, up to 66.8 J/g, which indicates that the mild conditions applied in the processing of the liquid resin allow the integrity of the microcapsules to be preserved. This is also confirmed by the improved thermal management performance observed through thermal camera imaging measurements. Microscopy techniques showed that the PCM phase is preferentially distributed in the interlaminar region, which accounts for the observed decrease in the interlaminar strength and the flexural properties with an increase in the PCM content. These results show a potential for the future development of multifunctional thermoplastic composites with elevated thermal energy storage capabilities. POLYM. COMPOS., 40:3711-3724, 2019. (c) 2019 Society of Plastics Engineers