Do-It-Yourself Materials are created through individual or collective self-production experiences, often by techniques and processes of the designer's own invention, as a result of a process of tinkering with materials. They can be new materials with creative use of other substances as material ingredients, or they can be modified or further developed versions of existing materials.
Rognoli, V., Bianchini, M., Maffei, S., Karana, E. (2015). DIY Materials. The Journal of Materials and Design, 86: 692-702. (S)