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Helmets are ubiquitously used form of protective equipment in various industries including but not limited to automotive, sports, construction, and even space. A common major drawback in helmets is their poor thermal management. In this study, in order to reduce the dependency on active cooling methods and to conserve same helmet design, a composite thermal liner based passive cooling mechanism is proposed. A multifunctional liner consisting of uniformly distributed thermally conductive graphene oxide nano sheets and icosane is prepared. Specimens were characterized using mechanical and thermal methods and a helmet liner cast out of a 3D?printed mold was tested to measure impact energy absorption using a home?built helmet impact testing setup (HITS) in accordance with ASTM D7136/D7136M?20. The liner is expected to deform, thereby absorbing the energy from the impact and eventually reducing the impact experienced by the user. The material (10X?GOME?0.75), obtained after careful optimization of the mechanical and thermal properties of different combinations of varying weight fractions of the fillers, exhibits about 300% greater deformation over an unmodified epoxy (UME) liner (0.3% strain), and also shows 98% strain recovery over a fatigue test of >7500 cycles, as compared to 90% strain recovery of the UME liner which diminishes considerably over time. Thermal characterization shows heat absorption by the material at about 37 ?C, which is the average human body temperature. Such a material can have future in developing lightweight next?generation helmets with better thermal management for use in various fields of use.This article is protected by copyright. All rights reserved.