Macromolecular design, polyphosphazenes

In many respects, the polyphosphazenes are the prototype inorganic backbone polymers, that exemplify the principles of ring-opening and condensation polymerization, macromolecular substitution reactions and their potential for molecular design, and an enormous range of derivatives with the same backbone but different organic side groups. 

Well-defined polyphosphazene block copolymers with poly(ferrocenylsilane) (PFS) have also been reported, where the combination of the crystallinity of the PFS block and versatility of the polyphosphazene block crystallisation-directed living supramolecular polymerisations lead to spatially defined and controllable nanostructures [59]. Although not designed specifically for medical applications, they show a prime example of how the tunability of polyphosphazenes can be exploited for advanced macromolecular engineering. 

---