The Study on the Microstructures and High Performances of Melt Blending Polyurethane/Multiwalled Carbon Nanotubes Composites

A melt blending process was employed to prepare nanocomposites based on thermoplastic polyurethane (TPU) and multiwalled carbon nanotubes (MWNT). The content of MWNT filled in TPU was increased till 40 phr (parts per hundreds of rubber). The morphological, structural and mechanical properties of the resulting TPU nanocomposites were systematically investigated using scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), dynamic mechanical thermal analysis (DMTA) and tensile testing. The results indicated that the unmodified MWNT were dispersed finely and uniformly in the TPU matrix beyond expectation, and the microphase separation structures of the TPU nanocomposites were slightly affected by the presence of MWNT. The mechanical properties of the TPU nanocomposites containing various amounts of MWNT at both room temperature and 120 °C were studied, which demonstrated that the modulus of TPU were greatly increased and the high temperature tensile strength of TPU was also prominently improved when MWNT content is higher. Moreover, the TPU nanocomposites exhibited improved thermal and electrical conductivities that might mean the TPU/MWNT nanocomposites have potential application as multifunctional materials.