Fluoroalkoxyphosphazene

In the mid-1970s Firestone announced the availability of PNF Rubber. This rubber has been discussed in Section 13.10 and whilst referred to as a poly(fluoroalkoxyphosphazene) may be considered to be a direct descendant of the inorganic rubber first prepared by Stokes in 1895. 

Figure 12.30 Potential uses of polyphosphazenes (a) A thin film of a poly(aminophosphazene) sueh materials are of interest for biomedical applications, (b) Fibres of poly[bis(trifluoroethoxy)phosphazene] these fibres are water-repellant, resistant to hydrolysis or strong sunlight, and do not burn, (c) Cotton cloth treated with a poly(fluoroalkoxyphosphazene) showing the water repellaney eonferred by the phosphazene. (d) Polyphosphazene elastomers are now being manufaetured for use in fuel lines, gaskets, O-rings, shock absorbers, and carburettor eomponents they are impervious to oils and fuels, do not bum, and remain flexible at very low temperatures. Photographs by eourtesy of H. R. Allcock (Pennsylvania State University) and the Firestone Tire and Rubber Company.

The properties of fluoroalkoxyphosphazene polymers and copolymers [N=P(OR)2ln (R- = fluoroalkoxy-group) have been described. Condensation of the phosphazenes, (Cl3PNPh)2 and C3N3(N=PCl3)3, with... 

Poly(Fluoroalkoxyphosphazene) Elastomers. When I is substituted with a mixture of trifluoroethoxide and telomer fluoroalkoxides, an elastomer II is obtained having a fluorine content of approximately 55 percent. A small amount of an unsaturated cure site may also be Incorporated into the polymer to promote vulcanization. 

Because of its excellent range of properties and reliability, poly(fluoroalkoxyphosphazene) elastomers are used as seals, gaskets, and shock mounts in demanding military, aerospace, petroleum and industrial applications. In addition, applications under development for this elastomer include fuel hoses for artlc use, coated fabrics for protective clothing, sealants, coatings and medical devices. 

The poly(fluoroalkoxyphosphazene) elastomers offer a unique combination of properties including a wide operating temperature range, excellent fuel and oil resistance and low temperature properties superior to those of the fluoros11leones and fluoropolymer elastomers. 

JThe effect of the substituent on the properties of the polyphosphazenes is not fully understood. For instance, [NP(OCH ) ]n and [NP C CH. homopolymers are elastomers (8,29). Synthesis using lithium, in contrast to sodium, salts is claimed to produce rubber-like fluoroalkoxyphosphazene polymers (30). The presence of unreacted chlorine or low molecular weight oligomers can affect the bulk properties (31,32). Studies with phosphazene copolymers both in solution and in the bulk state (29,33-38) indicate a rather complex structure, which points out the need for additional work on the chain structure and morphology of these polymers. 

Two commercial phosphazene elastomers were developed and marketed in the mid-1980s, namely, poly(fluoroalkoxyphosphazene) elastomer (ASTM International designation FZ) and poly(aryloxyphosphazene) elastomer (ASTM International designation PZ) [109]. The structure of the fluorinated product is as follows [110] ... 

This increasingly important topic has been reviewed in general, - > and in terms of specific applications of fluoroalkoxyphosphazene polymers. 

Several new fluoroalkoxyphosphazene polymers have been synthesized and the conformational properties of these compounds explored, using the methods described in ref. 121. 

The properties of a fluoroalkoxyphosphazene rubber have been evaluated there... 

Stabilization of Poly(fluoroalkoxyphosphazene) (PFAP) Elastomer against Thermal Degradation... 

T)oly (fluoroalkoxyphosphazenes) (PFAP) (I) are semi-inorganic poly-mers that contain a phosphorus nitrogen chain. Pendant fluoroalkoxy groups are attached to the phosphorus to impart hydrolytic stability and hydrocarbon resistance. 

G. Allen et al. (10) studied the thermal degradation of several poly(aryloxy- and fluoroalkoxyphosphazenes) by use of isothermal TGA and retention of solution viscosity. Thermal stability was determined by the temperature at which the samples exhibited 10% weight loss. No mechanism was presented for the thermal degradation. 

No studies have been published on the thermal degradation of poly(fluoroalkoxyphosphazene) (PFAP) elastomers. In this paper we report the first study on the mechanism of the thermal degradation of a PFAP elastomer (II). The bis(8-oxyquinolate)zinc(II) stabilization of PFAP (II) against thermal degradation also is reported and a mechanism for stabilization is proposed. 

N3Pj(CH2C02CH=CH2) [0(CH2CH20)jMe)y which is crosslinked at the olefin site . Fluoroalkoxyphosphazene fluids are under consideration for high temperature lubricants , electrical... 

Polyfll 40, Polyfll 70. See Aluminum silicate Polyfll 100. See Aluminum hydroxide Polyfll DL, Polyfll F, Polyfll FB, Polyfll HG, Polyfll HG-90, Polyfll X, Polyfll XB. See Aluminum silicate Polyfin. See Polyethylene wax Polyflex 300 Retention Aid. See Polyacrylamide Polyfluoroalkoxyphosphazene Synonyms PNF Poly (fluoroalkoxyphosphazene) elastomer Definition Elastomer with exc. low-temp, flexibility, good resist, to weather/soivs./acid, good mech. props, at -75 to 150 C... 

Poly (fluoroalkoxyphosphazene) elastomer. See Polyfluoroalkoxyphosphazene Polyfoam. See Polyurethane, thermoplastic Polyfoam sponge. See Polyurethane foam Polyfon F, Polyfon H, Polyfon 0, Polyfon ... 

The linear poly(fluoroalkoxyphosphazenes) are used commercially as elastomers for arctic conditions. Cross-linked network products of the cyclic oligomers are suitable for surface coatings or reinforced resins for the temperature range 250-550°C. 

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