Mechanical properties and morphology of nano-reinforced rigid PU foam

This study is dedicated to the investigation of the change in mechanical properties of rigid polyurethane foam reinforced with carbon nanoparticles. Pure and nano-reinforced polyurethane foams were produced by an in situ polymerization technique. Carbon nanotubes (single-walled carbon nanotubes and multi-walled carbon nanotubes) and carbon nanofibers were used as reinforcing particles. Diphenylmethane 4,4'-diisocyanate treatment of carbon nanoparticles was performed in order to improve the interaction of nanoparticles and polymer matrix. The alterations of morphology and mechanical properties of the nano-reinforced polyurethane foam were studied by varying the amount of both pristine and modified carbon nanoparticles. Compression tests revealed an improvement of both compressive Young's modulus and compressive strength, and scanning electron microscope observations showed a decrease of the average cell size of the foam.