Synthesis of boron nitride via LC borazine oligomers

Boron nitride is formed when the borazine oligomer is heated above 1000 C. This is a particularly novel processing route because it of ers 

The crystallinity and morphology of the BN has been shown to be dependent on various processing parameters including heating rate, maximum temperature, soak time and atmosphere. One primary factor controlling the structure of the ultimate BN, however, is the development of structure in the LC oligomer at low temperatures. 

The increase in the properties of the C/BN suggests a structure more similar to that observed in C/C with a mesophase pitch-derived matrix. 

In both composites, the planar molecules facilitate orientation of the crystalline structure parallel to the fiber—matrix interface. 

In conclusion, the liquid crystalline character which has been observed in the inorganic borazine oligomers provides a mechanism for the development of an oriented structure in BN. It is now understood that the interlayer spacing must be close to that of theoretical BN to produce a stable structure. The borazine oligomer offers a convenient 

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