Used primarily as a water-soluble azo initiator in radical polymerization reactions. It decomposes upon heating to generate free radicals, making it effective for initiating the polymerization of vinyl monomers such as styrene, acrylates, and methacrylates. Commonly employed in emulsion, suspension, and solution polymerization processes. Its carboxylic acid groups enhance solubility in polar media and can aid in anchoring the initiator to polymer chains or surfaces, allowing for controlled reaction kinetics. Also utilized in the synthesis of functional polymers and block copolymers due to its relatively low decomposition temperature and predictable radical generation rate.