Fullerene-induced crystallization toward improved mechanical properties of solvent casting polycarbonate films

This work provides a facile strategy to induce crystallization of polycarbonate (PC) through solvent casting method. Pristine fullerene (C 60 ) and PC-modified C 60 nanoparticles are applied as nucleating agents for PC, and the crystallization behavior of PC nanocomposite films is controlled by solvent casting preparation conditions. To investigate the relationship between crystallization behavior and mechanical properties of PC nanocomposite films, X-ray diffraction, differential scanning calorimetry, polarizing microscope and tensile tests are carried out. Pristine C 60 can only induce the formation of bulk PC spherocrystals which have no help or even deteriorates the mechanical properties of PC/C 60 nanocomposite films. By contrast, the PC-modified C 60 achieves uniformly disperse in the matrix and induces the formation of microcrystalline structures. It is found that appropriate degree of crystallinity for the PC/modified C 60 nanocomposite films can effectively improve the mechanical properties. Typically, the PC/0.50 wt%-modified C 60 nanocomposite films prepared under 40 °C by tetrahydrofuran exhibits up to a 33% increment in tensile strength and 45% increment in Young’s modulus compared to neat PC films.