are a unique class of polymers developed primarily by Professor
H. Allcock at Penn State during the 1960ís. Polyphosphazenes
represent the single largest class of polymers and are differentiated
from most conventional polymers by their route of synthesis, their
synthetic versatility, tunable hydrolytic degradability, high thermal
and oxidative stability and broad range of physical, chemical and
mechanical characteristics. Due to their unique synthetic pathway,
polyphosphazenes offer the promise of circumventing many of the
issues associated with classical polymerization.
Polyphosphazenes consist of an inorganic phosphorous-nitrogen backbone
and reactive pendant side groups that may be organic, organometallic
or inorganic in nature. Polyphosphazenes are constructed by initially
synthesizing a polymer backbone called polydichlorophosphazene.
The backbone's highly reactive sidegroups are then substituted with
chosen building blocks through well-established methods of organic
chemistry. Polyphosphazene molecules can range from low molecular
weight molecules of 1Kd-2Kd to very large macromolecules of 2000Kd-10000Kd.
The characteristics of the polyphosphazene backbone, synthetic
route and PSIís proprietary technology make it possible
to design-build a tremendous range of Polyphosphazene
polymers with tunable properties. Consequently the range of
potential Applications includes both biomedical
and advanced materials.