Enhanced thermal and mechanical properties of polyimide composites by mixing thermotropic liquid crystalline epoxy grafted aluminum nitride

In this paper, we have fabricated thermotropic liquid crystalline with epoxy groups grafted AlN nanoparticles (LCE-g-AlN) and then incorporated these into polyimide (PI) matrix to obtain the composites. The structure of LCE-g-AlN was charactered by Fourier-transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analyses (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The morphology and thermal properties of composites were systematically investigated. The morphology of the PI/LCE-g-AlN composites performed by scanning electron microscopy (SEM) indicating a homogeneous distribution of LCE-g-AlN nanoparticles in the PI matrix. Moreover, the value of Young’s modulus and tensile strength of the PI composites was increased by 78.3 % and 22.7 % in comparison with neat PI, respectively. The value of storage modulus of the PI composites achieved 7897 MPa with the incorporation of 10 wt.%, which increase 159.6 % compared with the neat PI (3035 MPa).