Homophthalonitrile are a relative new class of commercial high performance engineering thermosets. They exhibit very high thermal and oxidative stability, and outstanding high-temperature properties. Infact, Homophthalonitriles have one of the highest decomposition temperature of all organic thermoset polymers which can approach 500℃ in air. Both, the high thermal stability and the high char yield contribute to the outstanding high-temperature performance. However, homophthalonitriles have also some major limitations and shortcomings. For example, they are very expensive and difficult to process, relative to conventional thermoset resins.
