Thermal energy storage systems that utilize phase change materials (PCMs) for latent heat storage are attractive options for the passive control of building heating and cooling. In this study, we present a facile method to produce and print PCM-filled inks by a direct ink writing (DIW) technique that leverages spherical PCM particles as viscosity modifiers in a matrix of photocurable resin. We successfully printed inks with up to 63 wt% PCM, which have an excellent thermal regulation capacity and nearly no leakage over 200 heating and cooling cycles in the presence of surfactant and at different pH values. We also demonstrated that PCMs with different melting points (n-eicosane, paraffin wax, and n-hexatriacontane) can be simultaneously integrated into a resin and printed without detriment to the structure or integrity. The excellent adaptability of DIW offers the ability to tailor the loading level of different PCM particles to achieve desired thermal energy management performance and gives control over the structure of the printed objects. We used the PCM-filled ink to print a 9.5 x 6.7 x 10 cm hollow house and demonstrated that the inner cavity maintained a 40% lower temperature than the external environment. Thus, our approach to using PCM particles as both viscosity modifiers for 3DP and active energy management material can be used to produce effective thermal buffers and is compatible with a wide range of photopolymer matrices and PCMs, without requiring prior microencapsulation of the PCMs.

3D printed polymer-phase change material composites for thermal energy regulation

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.