Grafting boron nitride nanotubes: From polymers to amorphous and graphitic carbon

In this article, using an atom transfer radical polymerization approach, for the first time polystyrene (PS) and polymethyl methacrylate (PMMA) were grafted covalently on boron nitride nanotubes (BNNTs). Then, a technique was developed to fabricate novel amorphous or graphitic carbon-BNNTs composites with a perfect physical contact between the two phases using the polymer-functionalized BNNTs. BNNTs-carbon-balls composite structures were first successfully fabricated. Other experimental route revealed that a C-BN compound nanotubular nanostructure can be fabricated by using polyvinyl pyrrolidone wrapped BNNTs as an effective precursor, which possess well-defined composition variations and a clear interface between the carbon and BN tubular fragments. The obtained polymer-functionalized BNNTs and carbon-BNNTs composites are useful for the mechanical enhancement of polymeric matrixes and in various electrochemical devices.