Reactivity of Resorcinol Formaldehyde Resin with Nitric Acid
Solid‐state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25–55°C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off‐gassing. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25°C applied temperature and 0.625 M at 66°C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.