 Hexagonal boron nitride nanocrystal/graphite nanoflakes (h-BNNC/GNFs) are prepared.  These h-BNNC/GNFs are fabricated via a facile in-situ thermal treatment process.  h-BNNCs are highly crystallized and anchored on the surface of graphite nanoflakes.  These h-BNNC/GNFs exhibit excellent microwave absorption properties.

No abstract

No abstract

No abstract

A new polymeric boron nitride (BN) precursor poly[(phenylamino)borazine] (PPAB) with good melt‐processing performance was successfully synthesized by reaction of B‐trichloroborazine (TCB), aniline, and N‐methylaniline under mild conditions. The as‐synthesized PPAB as well as its structural evolution during the ceramic conversion was studied by means of various complementary techniques. The effect of process parameters including monomer ratio, reaction time, and reaction temperature on the properties of polymers was investigated, and the optimized parameters were obtained. Gel permeation chromatography (GPC) analysis of typical PPAB revealed that the number‐average molecular weight (Mn) was 30,520 Da and the polymerization degree was 319. The polymer could be converted to BN ceramics under ammonia atmosphere at 1200°C with carbon content as low as 0.9wt%. The PPAB polymer could be melt‐spun into continuous polymer fibers by hand drawing, which could be further transformed into BN ceramic fibers with good quality. The PPAB polymer is promising for applications that require BN precursor with stable melt processability.