Hexafluoroisopropylidene-Containing Polymers for High-Performance Applications

Abstract

High-performance polymers are used in applications demanding service at enhanced temperature while maintaining their structural integrity and an excellent combination of chemical, physical, and mechanical properties. Some of the important polymers in this respect are polyimides, polyamides, and polybenzazoles. However, all of these polymers have a common problem of processing difficulty due to their infusibility and poor solubility in organic solvents. The reasons are strong interchain forces, inherent macromolecular rigidity, or semicrystallinity. A great amount of work has been directed to making polymers more tractable, soluble, and processable without sacrificing their high-performance characteristics. Thus, the last two decades have witnessed the spectacular growth of research in a new polymer type, the one containing hexafluoroisopropylidene (6F) groups. Incorporation of 6F units into the macromolecular chain increases the solubility, thermal stability, flame resistance, glass transition temperature, oxidation resistance, adhesion, optical transparency, and environmental stability, while decreasing the crystallinity, dielectric constant, water absorption, and color [1].