J. Guan, A. Derdouri, B. Ashrafi, A. Benhalima, K.S. Kim, C.T. Kingston, B. Simard
National Research Council Canada,
Keywords: boron nitride nanotube, chemical functionalization, polycarbonate nanocomposite
Summary:Carbon nanotubes (CNTs) integrated polymer nanocomposites demonstrated promising trends to replace traditional metal materials for lightweighting applications. Similarly, boron nitride nanotubes (BNNTs), which are structurally analogous to CNTs, possess complimentary properties, including the optical transparency, electrical insulation, higher temperature stability, neutron absorption and piezoelectricity, that create new possibilities in the fields of structural and functional composites, particularly in the fabrication of optically transparent, thermally and scratch resistant materials. Although discovered in 1995, the lack of mass production technology has hampered advances in all areas of BNNT-nanocomposites until recently. Indeed, the recent advances at NRC Canada in large-scale BNNT production and commercialization using a high-temperature plasma technology offer the opportunities of developing this new frontier of material sciences[1-3]. Just like with CNTs, the main issues in manufacturing composites with superlative properties are dispersion and interfacial adhesion with the polymer matrices. The most effective method used to resolve these issues is the surface chemical functionalization to obtain stronger adhesion at the interface of BNNT/polymer matrix. Here, we report the chemical functionalization of BNNT materials for integration into polycarbonate (PC) polymer matrix. The chemical functionalization is performed through in-situ B-N bond cleavage by liquid bromine treatment in the course of removal of elemental boron by-product. We will describe the chemical functionalization strategy in some detail and report primarily results and characterization of the resulting BNNT reinforced PC-nanocomposites. References:  K. S. Kim, C. T. Kingston, A. Hrdina, M. B. Jakubinek, J. W. Guan, M. Plunkett, B. Simard, ACS Nano 2014, 8, 6211–6220.  K. S. Kim, M. J. Kim, C. Park, C. C. Fay, S. H. Chu, C. T. Kingston, B. Simard, Semicond. Sci. Technol. 2017, 32, 013003.  J. W. Guan, B. Ashrafi, Y. Martinez-Rubi, M. B. Jakubinek, M. Rahmat, K. S. Kim, B. Simard, Nanocomposites 2018, 4, 10–17.  J. W. Guan, K. S. Kim, M. B. Jakubinek, B. Simard, ChemistrySelect 2018, 3, 9308-9312; J. W. Guan, B. Simard, PCT/CA2018/051254.