New polymer syntheses, 36. Functionalized aromatic polyethers derived from 4′-substituted 2,6-difluorobenzophenones

Toluene, anisol, thioanisol, 4-phenoxyacetophenone and N,N-diacetyl-4-phenoxyaniline were subjected to a Friedel-Crafts acylation with 2,6-difluorobenzoyl chloride. The resulting 4′-substituted 2,6-difluorobenzophenones 1a – e were condensed with trimethyl silylated Bis-phenol-A ( 2 ) to yield homopolyethers with pendant functional groups. A series of copolyethers was analogously prepared by concondensation of 4′-substituted 2,6-difluorobenzophenones with a diphenol and 4,4′-difluorobenzophenone ( 4a ) or bis(4-fluorophenyl) sulfone ( 4b ), and another series by cocondensation of 2 with mixtures of 4′-substituted 2,6-difluorobenzophenones and 2,6-difluorobenzonitrile ( 8 ) or 2,6-difluoropyridine ( 9 ). All polyethers were characterized by inherent viscosities, elemental analyses and DSC-measurements. In individual cases GPC-measurements, thermomechanical and thermogravimetric analyses were conducted. The quantitative polymer-analogous oxidation of methylthio groups into methylsulfinyl and finally into methylsulfonyl groups is demonstrated.