Facing the reduction of fossil resources and the constant increase of energy needs, hydrogen becomes as one of the most promising vector to store energy and to produce electricity via PEMFC (Polymer Electrolyte Membrane Fuel Cell). Nevertheless, one of the challenges is to be able to store H2 gas at high pressure in all-polymer tank, denoted as type IV. This tank is based on an internal polymer liner which acts as a barrier for hydrogen and an external structural composite envelop which could resist to service pressures up to 700 bars. In fact, such a high pressure allows to increase storage density and the use of such tanks in automotive applications. Polymer liners based on polyethylene or polyamide could be processed by rotomolding but higher perfomances materials need to be developed to fulfill the requirements of such an application. As a consequence, the reactive rotomolding (RRM) could allow the processing of liners based on designed polyamides as well as thermosets such as polyurethanes and epoxies. In this work, two types of polyamides will be condidered for RRM, i.e. polyesteramide (PEA6) and polyamide 6 (PA6), synthesized from the ring opening polymerization of caprolactone with caprolactam and caprolactam, respectively. A second type of reactive systems is considered in this study, i.e. epoxy-amine systems envolving polyaddition polymerization with various diamines hardeners and additives were used. The ex-situ rheokinetics and the transformations (crystallization and vitrification phenomena) studied for temperatures similar to those encountered for the reactive rotomolding process of PEA6 and PA6 showed that the reaction could be completed from 140 to 160°C for 30 min. Optimal conditions for RRM of such reactive systems were defined by changing the polymerization conditions in real processing conditions. The relationships between the SBR (Solid Body Rotation) viscosity and the minimal resulting thickness were established.