4-Fluorostyrene monomer

Ballard Advanced Materials Corporation (BAM) ionomers are sulfonated copolymers of trifluorostyrene and substituted tri-fluorostyrene monomers. Ballard Advanced Materials, a subsidiary of Ballard Power Systems, investigated the conducting polymers based on polyphenylquinoxaline (PPQ). These can be sulfonated in a wide range and were referred to as Ballard first-generation (BAMIG) membranes, but these membranes were found to have short durability. To overcome this problem, BAM developed a second generation of advanced membranes... 

A preferable system is poly(p-fluorostyrene) doped into poly(styrene). Since rotations about the 1,4 phenyl axis do not alter the position of the fluorine, the F spin may be regarded as being at the end of a long "bond" to the backbone carbon. In standard RIS theory, this polymer would be treated with dyad statistical weights to automatically take into account conformations of the vinyl monomer unit which are excluded on steric grounds. We have found it more convenient to retain the monad statistical weight structure employed for the poly(methylene) calculations. The calculations reproduce the experimental unperturbed dimensions quite well when a reasonable set of hard sphere exclusion distances is employed. 

Fluorostyrene fraction of the initial monomer loading Weight of initial monomer (M) loading... 

Fluorostyrene (4FS) monomer is also commercially available product and can be distilled before used (bp. 67°C/50 mmHg). 

Poly(TSE-co-4FS) Copolymers Copolymerization of fluorine ring substituted 2-phenyl-1,1-dicyanoethene (TSE) with 4-fluorostyrene (4FST) was prepared from an equimolar monomer feed composition in the presence of a 1,1 -Azobis(cyclohexanecarbonitrile) (ABCN) as the radical initiator [88]. The yield was close to 59% (Scheme 20.7). Homopolymerization of 4FST was conducted under identical conditions as those in the copolymerization (Yield = 76%). 

High Tg of poly(TSE-co FST) copolymer (Tg = 156°C), in comparison with that of 4-fluorostyrene homopolymer (P4FST) (Tg = 104°C) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer units. 

These include anionic polymerizations of some conjugated monomers such as -tri-fluoromethyl acrylates, fluorostyrene derivatives and 1,4-perfluoro-butadiene (17), and condensation polymerization to afford such aromatic fluoropolymers as polyarylates and aramides (18). In addition, fluorinated polyimides are on a way of evaluation for practical applications in the electronics field. 

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