Poly AsF5 doped

Figure 7. Conductivity versus time in the AsF5-doping of 0.025 cm thick films of poly(p-phenylene sulfide) illustrating effect of added ASF3 on doping rate(62).

The literature on conductivity in poly(p-phenylene sulfide) is confused. According to Shacklette et al.74) heavy doping with AsF5 causes reduction of the polymer with the formation of fused benzothiophene structures which are responsible for conjugation. This would more properly place poly(p-phenylene sulfide) in the category of precursor polymers, discussed later. On the other hand, Friend and Giles 75) proposed an intrinsic conduction mechanism, based on optical measurements and Tsukamoto et al. 76) have presented XPS and 13C NMR measurements to support this view. 

Table 2 contains idealized structures of some CPs with typical dopants and values for the conductivities of thin films. The exact structures of PPy and poly thiophene (PT) are unknown. Polyacetylene is the most crystalline and PANi can exist in several oxidation states with electrical conductivities varying from 10 S/cm to the values reported in Table 2. In its undoped state, PPS is an engineering thermoplastic with a conductivity of less than 10 S/cm. Upon doping with ASF5, conductivities as high as 200S/cm have been obtained after casting a film from a solution of AsFsP ...

Particle size increases from 100 up to 500 A at use of the mixed catalyst and the increase in density of films is observed. A filtration of suspension it is possible to receive films of any sizes. On the various substrates possessing good adhesive properties, it is possible to receive films dispersion of gel. Polymer easily doping AsF5, FeCl3,l2, and other electron acceptors. Preliminary tests have shown some advantages of such materials at their use in accumulators [48]. Gels poly acetylene with the similar properties. 

The first doped poly(phenylenevinylene) was reported by Karasz using ASF5 as dopant its conductivity was 3 S/cm. Stretching the precursor film at high temperature and doping with ASF5 or SO3 yielded conductivities up to 2800 S/cm. 

Poly(/ -phenylesulfide), PPS, (white powder, Tg 92 °C, mp 270-290 °C, 65% crystallinity) was the first melt-proccessible polymer to be doped with strong electron acceptors (e.g., ASF5) to yield highly conductive products [90]. The first laboratory synthesis of PPS was reported by Macallum [91] and involved the melt reaction of 1,4-dichlorobenzene, sulfur and sodium carbonate. A commercially product has been available as powder, film or fiber since 1973 from Phillips Petroleum under the trade name Ryton it is produced from 1,4-dichlorobenzene and sodium sulfide (high-pressure process) in a polar solvent (N-methylpyrrolidone) [92]. 

Poly(p-phenylene sulfide), PPS, is the only commericially available processible precursor to a conducting polymer complex. Gas phase doping of PPS films with ASF5 leads to substantial chemical and physical alteration of the polymer and a substantial loss of the mechanical properties of the parent polymer. In this section we will describe a recently discovered method which allows the retention of processibility in the PPS system,... 

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