Tetrabutylammonium bromide is a white crystalline powder or granule, hygroscopic with a slight amine odor. It is stable under normal temperature and pressure, but readily decomposes at high temperatures (>200°C). As a quaternary ammonium salt, it exhibits strong phase transfer catalytic activity.

1. Organic Synthesis: Efficient phase transfer catalyst (PTC) for nucleophilic substitution, oxidation, reduction, condensation and other reactions.

2. Pharmaceuticals & Pesticides: Pharmaceutical intermediate, ion-pair reagent in drug synthesis.

3. Chemical Additives: Surfactant, emulsifier, dispersant, extreme pressure additive.

4. Electrochemistry: Additive for lithium battery electrolyte, electroplating additive.

5. Analytical Reagent: Ion-pair chromatography reagent, polarographic analysis reagent.