As the consequences of outgassing can be detrimental to the performance of on-board instruments, it is necessary to accurately predict the risks of molecular contamination on sensitive surfaces and thus to optimize the outgassing modeling. Nevertheless, long-term prediction could be greatly modified, as the input parameters for modeling are based on outgassing kinetics studies with, most of the time, freshly cured materials, that's why it is important to consider the story of the material.In this study, we aim at improving our physical and chemical understanding of the outgassing of space materials that could be affected by different environmental conditions during on ground activities (such as preliminary thermal treatments, thermal cycling under vacuum or long-term storage...) and in orbit (such as space environment parameters and particularly UV radiation). For that purpose, different materials have been selected (EC2216, EC9323, SG121D, PCB+/-MAPSIL 231B) to be exposed to these environmental conditions. The outgassing kinetics of these materials will be compared and their physico-chemical properties will be characterized before and after exposure using different analytical techniques. Then, numerical simulations will be improved with optimized parameters to predict more realistic outgassing behavior under various environmental conditions.With this combined experimental and modeling approach, this study can gain a better knowledge of the mechanisms of outgassing, taking particular account of environmental conditions on ground and in flight.