Extraordinarily high plastic deformation in polyurethane/silica nanoparticle nanocomposites with low filler concentrations

We have synthesized segmented polyurethane (SPU)/silica nanoparticle (SiNP) nanocomposites with extraordinarily high tensile strength and strain-at-break using an in-situ polymerization method with low SiNP concentrations. A 20-fold increase in strain-at-break compared with the pristine polymer has been achieved for the 0.5 wt% SiNP nanocomposites. A suite of characterization tools including transmission electron microscopy, ultra-small angle X-ray scattering, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis has been used to correlate the phase morphology, crystallization, and mechanical properties. The location of SiNP in the phase separated SPU is believed to be the main reason for the mechanical property enhancement.