Boron Nitride Quasi-Nanoscale Fibers: Controlled Synthesis and Improvement on Thermal Properties of PHA Polymer

High-purity h-BN quasi-nanoscale fibers were successfully synthesized by annealing oriented fiber-like precursor, an adduct of melamine with boric acid at a ratio of 1:2 (M · 2B), under ammonia flow. A series of experiments have been conducted to obtain an optimum condition for generating nanoscale precursor for the synthesis of h-BN quasi nanofibers with an average diameter of ∼500 nm and length of several hundred micrometers, respectively. The fiber is a polycrystal composed of numerous disordered h-BN layers, with some stacking voids and defaults. In addition, the effects of BN fibers on the thermal conductivity and stability of biodegradable polyhydroxyalkanoate (PHA) have been studied. It is worth noting that with the addition of 2 wt% BN fibers, the thermal properties (thermostability and thermal conductivity) of the as-prepared composites have been influenced substantially.