Lightweight hybrid organic-inorganic geopolymers obtained using polyurethane waste

Lightweight geopolymers from wastes with reduced thermal conductivity have become an important trend for green buildings sector. In this work, organic-inorganic hybrid geopolymers were prepared from polyurethane powders wastes (polyurethane foam and polyisocianurate foam). Chemical, physical and mechanical properties of geopolymers, manufactured with different percentages of polyurethane wastes are reported and discussed. The FTIR spectroscopy allowed to verify the influence of both polyurethane powders on the framework structure revealing H-bonds between polyurethane and inorganic phase. Flexural and compressive strengths showed that content and typology of the used polyurethane wastes affected the material behavior. The strength of hybrid geopolymers was maximized with polyisocianurate foam waste addition in a concentration lower than 14% in weight. Thermal conductivity was carried out on appropriate samples, showing that the hybrid geopolymers exhibit satisfactory isolation properties. The new materials proposed in this work represents an innovative solution, enhancing the thermal resistance of the buildings by using a waste intended for landfill.