Boron inorganic polymers

Alternative routes to boron nitride have been examined that do not require those challenging reaction conditions. These fall into three categories, which are (1) the pyrolysis of borazines (2) pyrolysis of organic or inorganic polymers that bear borazine groups as side units and (3) pyrolysis of polyhedral borane derivatives. 

Boron phosphate, an inorganic polymer of empirical formula BP04, can be prepared by heating phosphoric and boric acids to calcining temperature. It is a white infusible solid that vaporizes at 1450°C-1462°C without decomposition. As opposed to the tri-valency in boric oxide, most of the boron atoms in boron phosphate are tetra-coordinated (i.e., as B04 group, Figure 9.14). Commercially it is available from Budenheim.79... 

Boron is a most interesting element, it being at the changeover point in the Periodic Table from metals to non-metals. It is non-metallic, and with the possibilities of hybridisation is able to form a wide range of hydrides, oxides, halides and compounds with transition elements. It is of great importance in the field of inorganic polymers. 

Our attempt to obtain a silicon-boron hybrid polymer system was successful. Their complicated crosslinkable structure acts as a thermosetting resin to give thermal and mechanical stability with good processability. Carborane hybridization gives exceptional non-flammability. This is a kind of organic-inorganic hybrid system that has plastic versatility and ceramic stability. 

Inorganic polymers have backbone chains that do not contain carbon, as organic polymers do, but atoms such as oxygen, nitrogen, phosphorus, boron, silicon, and metals or alternating combinations of them. The side groups attached... 

Other Inorganic Polymers that Contain Phosphorus, Boron and Sulfur... 

The diverse collection of boron-nitrogen polymer chemistry summarized here points out that efforts in this area are fruitful and worthy of continuing attention. Furthermore, the considerable progress made in processing some of the polymers into useful ceramic compositions and forms demonstrates that fundamental inorganic polymer chemistry has practical and, perhaps in the near future, commercial utility. 

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