Polyphosphazenes coatings

Polyphosphazene Coated silica Magnesium oxide Antioxidants Peroxide... 

Verret, V., Wassef, M., Pelage, J.P., Ghegediban, S.H., Jouneau, L., Moine, L., et al., 2011. Influence of degradation on inflammatory profile of polyphosphazene coated PMMA and trisacryl gelatin microspheres in a sheep uterine artery embolization model. Biomaterials 32 (2), 339—351. 

Figure 3.6 Polyphosphazene-coated microneedles for intradermal adjuvant administration a) schematic representation, b) scanning electron microscopy image and c-d) optical microscopy images. Reproduced with permission from A.K. Andrianov,...

Phosphazene polymers are inherently good electrical insulators unless side-group stmctures allow ionic conduction in the presence of salts. This insulating property forms the basis for appHcations as wire and cable jackets and coatings. Polyphosphazenes also exhibit excellent visible and uv radiation transparency when chromophoric substituents are absent. 

Such polymers are as hydrophobic as poly(tetrafluoroethylene) (Teflon), with water contact angles in the range of 107°. But, unlike Teflon, polyphosphazenes of this type are easy to fabricate, are flexible or elastomeric, and can be used as coatings for other materials. ... 

Films of polyphosphazenes 5-9 were spin cast onto indium-tin oxide coated glass from a concentrated solution in methylethyl ketone. 

Many polyphosphazenes form strong films and membranes when solutions are spread on a flat surface and the solvent is allowed to evaporate. Some of these films have special properties such as resistance to UV radiation, and are thus of interest as coatings for solar cells, aircraft, or space craft. The polymer [NP(OCH2CF3)2] and related mixed-substituent derivatives have been studied from this viewpoint.1... 

As a coating offers increased anti-icing effectiveness and durability than fluorocarbon and silicone elastomers. These icephobic coats can reduce the accumulation of ice on products such as rooftops, aircraft, radomes, antennas, ships, and power-transmission lines. The weight of such accumulations of ice has led to aircraft crashes, fallen power lines, etc. The icephobic coats reduce the adhesive force between ice and a surface. Polyphosphazene elastomers possess these desired properties, in addition have low glass transition temperature (Tg), good environmental stability, curability, and moderate cost. 

Allcock and coworkers developed derivatives of the phosphazene polymers suitable for biomedical applications [35, 36]. Long-circulating in the blood, 100-120 nm in diameter, PEO-coated nanoparticles of the poly(organophospazenes) containing amino acids have been prepared. The PEO-polyphosphazene copolymer or poloxamine 908 (a tetrafunctional PEO copolymer) has been deposited on their surface [37]. 

A 1980 Naval Research Laboratory report provides data on the toxic combustion products evolved by burning polyphosphazene foams, with and without fire retardants. Toxicants produced were CO, CO2, 2-chlorobutane, 1-chlorobutane, benzene, toluene, and trichloroethylene (for foams not coated with fire-retardant paints) (11). 

A number of general reviews on polyphosphazenes have appeared. Specific reviews on polyphosphazenes deal with radiation graft polymerization, anionic polymerization, hydrogel microspheres,controlled biodegradability,coatings, and membrane separation. 

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