Rigid composite bio-based polyurethane foams: From synthesis to LCA analysis

This paper provides a bio-based polyurethane foam (PUR) solution, following a cradle-to-factory approach. The design of bio-based rigid PURs, reinforced with sustainable fillers have gained remarkable attention in "green" construction sector. Their marked performances make them a viable solution for synthetic counterparts' replacement. In this work, functionalized hemp fibers and silica powders were selected as reactive fillers, imparting multifunctional properties to the designed PURs. Hemp fibers underwent ultramilling, phenolation and/or nano-transformation to obtain four different filler types, i.e. nano-and micro-sized hemp particles, and functionalized hemp nano and micro-size couples. Silica nanoparticles were extracted from rice husk and functionalized with phytic acid. The composite PURs were prepared by adding 6 % wt of filler to cardanol/ vegetable-based polyol solutions. The effect of the filler's chemistry on the properties of the foams was inves-tigated. A Life Cycle Assessment of the filler production stages was performed to assess their eco-profile impact.