Published:29 Apr 2013
Phosphazenes remain an intriguing chemical system due to the unique incorporation of phosphorus and nitrogen into other organic and inorganic molecules. Typically, phosphazenes serve as scaffolds to which a variety of other molecular structures can be appended. Since phosphorus is pentavalent in phosphazene structures, two attachment points exist through which other molecules can be attached. It should be noted that this diverse chemistry is not limited to simple appendages, but the phosphorus and nitrogen structure itself can be manipulated into a range of molecules spanning from small molecule forms to macromolecular polymers. Furthermore, the incorporation of phosphazenes into organic systems provides much in the way of property enhancement. In this article, both continuing research into the application of specific phosphazenes and the formation of novel structures are reviewed. Applications, in many cases, appear to be the driving force behind much of the new research. Themes presented in this article include advances in phosphazene materials for energy storage, optical applications, biomedical tissue replacement, and immunoadjuvants; however the goal is to present these applications in terms of new chemical understanding of structure and function.