In the first part of this thesis, two perfluorinated polybenzoxazines are synthesized using a new approach. This novel method eliminates the rigid backbone that causes the brittleness of the previously synthesized fluorinated benzoxazine.; The benzoxazines are synthesized using two highly perfluorinated diamines, one aliphatic and one aromatic. The aliphatic diamine is obtained using a synthetic method that solves the problem associated with the two classic approaches: (a) Mitsunobu reaction and (b) sodium azide substitution. This method increases the yield by 13% and decreases the reaction time by 90%, allowing a scale-up of the highly fluorinated diamine that cannot be easily achieved using the previously known methods.; The diamines are used to synthesize perfluorinated benzoxazine monomers as well as main chain benzoxazines. The analogous hydrogenated main chain benzoxazines are also synthesized. The thermal and mechanical properties of the fluorinated polybenzoxazines are compared to those of the hydrogenated polybenzoxazines. The effects of the type of the amine as well as the curing atmosphere on thermal behavior, network properties and dielectric constant values are investigated.; In the second part of this work, the topochemical effect in the opening of the oxazine ring is analyzed by infrared spectroscopy. The synthesis and the phase behavior of a series of monofunctional side-chain monotropic liquid-crystalline benzoxazine monomers with the cyanobiphenyl group as a mesogen and different spacer lengths is described.
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