The objective of the research described in this thesis has been to improve the toughness of phenolic networks while maintaining flame resistance.  A four step synthetic scheme has been developed to prepare 4,4'-Bis(3,4-dicyanophenoxy)biphenyl(biphenoxyphthalonitrile).  A 700 g mol novolac oligomer
was cured with relatively low concentrations of this reagent (~20 wt %) into high Tg
(~190 °C) networks. The curing reaction was attrubuted to nucleophilic attack of the
phenolic hydroxyl on the nitrile groups of the phthalonitrile resulting in the formation of
heterocylic rings. TGA and cone calorimetry demonstrated that these networks have
excellent thermo-oxidative stability.novolac oligomer
was cured with relatively low concentrations of this reagent (~20 wt %) into high Tg
(~190 °C) networks. The curing reaction was attrubuted to nucleophilic attack of the
phenolic hydroxyl on the nitrile groups of the phthalonitrile resulting in the formation of
heterocylic rings. TGA and cone calorimetry demonstrated that these networks have
excellent thermo-oxidative stability.