The development of effective, light and cheap passive two-phase cooling systems is a major challenge in various industrial sectors, especially in the thermal control of on-board electronics. The objective of our work is to design, manufacture and characterize a polymer heat pipe. The manufacturing of these systems presently faces the difficulty to define and shape the technical polymers having properties compatible with the targeted application. The recent progresses in the additive fabrication methods allow foreseeing the possibility to remove this bottleneck. In this project, the conductivity of different commercial materials has been measured. Using these data, tailored material for AM has been manufactured. Demonstrators using both Fused filament fabrication and stéréolithographie (SLA) have been manufactured and characterized.