Sulfonated fluorinated poly

H. Ghassemi, J.E. McGrath, T.A. Zawodzinski, Jr., Multiblock sulfonated-fluorinated poly(arylene ether)s for a proton exchange membrane fuel cell. Polymer 2006, 47(11), 4132-M139. 

Scheme 2.28 Structure of sulfonated fluorinated poly(arylene ether) containing naphthalene moieties in the main chain. Taken from Ref. [137],...

Jeong et al. [147] synthesized a sulfonated fluorinated poly(aryl ether ketone) with pendant phenyl rings, as shown in Scheme 2.32. Both proton conductivity and WU increased with an increase in temperature. For example, the proton conductivity of a polymer membrane with DS=0.96 was 83mS/cm at 25 °C and 98mS/cm at 80 °C, comparable to that of Nafion 117 (proton conductivity=45 mS/cm at 25 °C and 96 mS/cm at 80 °C). The pendant phenyl ring containing sulfonic acid group improved WU from... 

Zhang et al. [151] used Ni(0)-catalyzed coupling copolymerization to synthesize a series of sulfonated fluorinated poly(p-phenylene-co-aryl ether ketone)s (SPP-co-PAEKs). Copolymerization with the sulfonated monomer 2,5-dichloro-3 -sulfobenzophenone (DCSB) and 2,2 - w[4-(4-chlorobenzoyl)]phenoxyl perfluoropropane (BCPPF) was carried out by varying the molar ratio of DCSBrBCPPF. The structure of SPP-co-PAEKs is shown in Scheme 2.35. 

Scheme 2.36 Structures of sulfonated fluorinated poly(arylene ether)s using different bisphenol units in the polymer main chain.

Table 2.12 Interesting Set of Properties Obtained for Synthesized Sulfonated Fluorinated Poly(Arylene Ether)s Including Thermal Degradation, Mechanical Properties, Oxidative Stability, Water Uptake, Swelling and Proton Conductivity for Variations of DS... 

Furthermore, Banerjee and group prepared sulfonated fluorinated poly(arylene ether sulfone) (IBQSH-XX) copolymers (where XX=20, 30, 40, 50, and 60 and DS=0.16, 0.26, 0.39, 0.47, 0.56, respectively) based on imidoaryl biphenol, namely, 3,8-few(4-hydroxyphenyl)-A -phenyl-l,2-naph-thaUmide (IB), by direct copolymerization with SDCDPS as the sulfonated monomer and QBF as the fluorinated monomer [160]. Sulfonated copolymers were obtained with M values in the range 41,200-60,200g/mol with D values in the range 0.96-1.89 the trend increased with an increase in the DS (0.16-0.56 as per H-NMR spectra). Scheme 2.36 shows a representative structure of sulfonated fluorinated poly(arylene ether sulfone) containing IB... 

Densely sulfonated fluorinated poly(arylene ether ketone) copolymers (SPAEK-xx, where xx=15, 20, 25, 30, and 35) was prepared by Pang et al. [172] and evaluated for proton conductivity. The Tg of the copolymers was in the range 193-231 °C and the T s% was in the range 364—390 °C, with a decreasing trend with an increase in the DS. The structure of the tetra-sulfonated fluorinated poly(arylene ether ketone) copolymer is shown in Fig. 2.11(a). 

Figure 2.11 (a) Structure of tetra-sulfonated fluorinated poly(arylene ether ketone) copolymer (taken from Ref. [172]) (b) TEM image of SPAEK-35. Reproduced with permission from Ref [172],... 

Scheme 2.46 Structure of comb-shaped densely sulfonated fluorinated poly(arylene ether)s with four sulfonic...

FIGURE 4.13 TGA traces of sulfonated-fluorinated poly(arylene ether sulfone)s in the salt form (a) and acid form (b) (under N2). (Reprinted after modification from Ghassemi, H. et al.. Polymer, 47(11), 4132, 2006. With permission.)... 

In 2006, McGrath and coworkers reported multiblock sulfonated-fluorinated poly(arylene ether sulfone)s (MB) for PEMs by the nucleophilic aromatic substitution of the dialkali metal salt of bisphenol-terminated poly(arylene ether sulfone) and decafluorobiphenyl-terminated poly(arylene ether) [28] (Scheme 4.10). 

Another synthetic approach has been reported by Nakabayashi et al. [36]. As described earlier, mnltiblock sulfonated-fluorinated poly(arylene ether sulfone)s were prepared by the bisphenol-terminated poly(arylene ether sulfone) and decafluorobiphenyl-terminated poly(arylene ether), which was obtained by an excess amount of DFBP and bisphenol-terminated poly(arylene ether sulfone). However, considering the high reactivity of DFBP, multiblock copolymers can be obtained by connecting hydroxy-terminated oligomers with a small amount of DFBP. That is, DFB functions as a chain extender. The synthetic procedure is depicted in Scheme 4.11. 

Rreparation and Evaluation of Sulfonated-Fluorinated Poly(arylene ether)s Membranes for Rroton Exchange Membrane Fuel Cell (REMFC). Electrochimica Acta. 49 2315-2323. 

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