Characterization of brominated poly(4-hydroxystyrene) derivatives containing unsaturated groups

Brominated poly(4-hydroxystyrene) (HS) derivatives containing unsaturated groups such as alkenyl or alkenoyl were investigated with infrared and ¹H nuclear magnetic resonance spectroscopy. HS derivatives have good thermal properties and their decomposition temperatures were higher than 300°C. Their thermal degradation behaviour is interpreted by the strength of electron withdrawal of substituent groups. The dielectric constants of HS derivatives can be predicted by the Clausius-Mosotti equation. The calculated values are found to agree with the observed values. The dielectric constants of the polymer can be reduced by replacing hydroxy groups with alkenoyl groups, especially methacryloyl units.