Cellulose nano/micro-reinforced polyurethanes

ARANGUREN, MIRTA I.

UBA, Buenos Aires

Workshop; Seventh J.J. Giambiagi Winter School-New Trends in Complex Materials; 2005

Conferencia invitada Seventh J.J. Giambiagi Winter School-New Trends in Complex Materials, Buenos Aires, 25-29 Julio 2005 The preparation and characterization of cellulose nanocrystals ?polyurethane composites is studied and analyzed. Microcrystalline cellulose was used as the raw material for producing cellulose crystals of submicron size, by acidic hydrolysis. The crystals were further suspended in dimethylformamide, resulting in a suspension that remained stable for 2-3 days. This preparation was further used to produce reinforced polyurethane by cast and pressure molding. The resulting material was characterized by their optical transparency, rheological, thermo-mechanical, mechanical and fracture responses. The results were analyzed and they indicate that a percolation behavior appears in the uncured system, while a strong covalent filler-matrix interaction is developed in the cured elastomeric materials.