5. Conclusions

This article presents methods for lightening gypsum-based mortar or plasterboard by incorporating lightweight polymer-based aggregates. Recycling polymeric materials in the form of shreds makes it possible to obtain a final material of acceptable quality, which is easy to process and complies with current regulations.

The microstructure of plaster, which crystallizes in the form of needles, governs numerous parameters such as hydration conditions, mechanical properties and the type of aggregates that can be used in their preparation. Thus, certain properties in the fresh or final (hardened) state are modified by the inclusion of polymer foam granules. Consequently, we can establish that the quantity of polymer foam used in the composition of the plaster is the factor that has the greatest influence on properties in both the fresh and hardened states.