Advanced thermal systems driven by paraffin-based phase change materials - A review

Advanced thermal systems designed and fabricated through paraffinic phase change materials have emerged quite fast until recently. However, most of the prior works have reviewed the fabrication strategies to tailor the poor thermal characteristics of paraffin waxes, as well as compiled the application-oriented studies related to thermal/cold storage, thermal management of batteries, photovoltaics, buildings, and so forth. In the present review, the advanced thermal systems, manipulated through multifunctional inherent traits of paraffin waxes, have been reviewed and systematically categorized into thermo-management, thermo-mechanical, thermo-responsive and thermo-chemical systems. In addition, guided by the previously reported results for paraffinic thermal composites, it is hereby recommended to urgently promote the synergistic tradeoff between thermal conductivity improvement and latent heat reduction so as to avoid the thermo-physical bottlenecks and the design challenges in the future. Additional attempts include proposals of an ideal phase change diagram, serving as a guide to understand the phase change theory henceforth, and a categorical flow chart of thermal reinforcements leading to fundamental principles to fabricate an ideal thermal composite. In all, the effort is mainly dedicated to bridge the gap between broad fields where paraffin waxes have been, directly or indirectly, deployed. Therefore, fundamental terminologies are necessarily defined and tabulated to establish a closer outlook for the experts of far-reaching fields.