Polyaddition of Fluorinated Vinyl Monomers
Novel anionic and radical polyaddition reactions that can be used to develop polymer synthetic methodology other than addition polymerization of fluorinated vinyl monomers are described. Anionic polyaddition reaction was carried out with bis(2-trifluoromethylacrylate) with ethyl cyanoacetate by employing a double Michael addition reaction accompanied by the formation of carbon–carbon bonds from carbon–hydrogen bonds since α-trifluoromethylvinyl compounds are good anion acceptors. Radical polyaddition was also developed with bis(perfluoroisopropenyl) compounds with several organic compounds possessing carbon–hydrogen bonds. The reaction afforded novel fluorinated polymers bearing organic segments in polymer main chains such as 1,4-dioxane, 18-crown-6 and alkanes, which had never been considered as direct starting compounds for the preparation of polymers. A facile method for the preparation of fluorinated hybrid polymers bearing alkylsilyl groups was developed using diethoxydimethylsilane and silsesquioxanes. Novel self-polyaddition was introduced using triethylsilyl perfluoroisopropenyl ether. A fluorinated polymer possessing five-membered ring structures in the main chain was afforded by radical cyclopolymerization of perfluoroisopropenyl vinylacetate. Radical shift mechanisms that have appeared only rarely in organic reactions were demonstrated. The anionic and radical polyaddition reactions presented here may be developed for the preparation of a wide variety of novel fluorinated polymers from several organic compounds bearing carbon–hydrogenbonds with fluorinated vinyl monomers.