Understanding alkenyl succinic anhydride (ASA) size reversion due to autooxidation

Abstract

Alkenyl succinic anhydride (ASA) is a sizing agent. The wettability of paperboard decreases when ASA is applied. The efficacy of ASA in board can be reversed under certain conditions, making the paper more hydrophilic and of lesser quality/value. Although it is broadly known that ASA size reversion is due to autooxidation in the presence of oxygen in air, the environmental parameters that initiate or catalyze this reaction are not well understood. Six different experimental set ups were used to understand how temperature, daylight, fluorescent light, ultravio-let (UV) light, and darkness affect oxidation of ASA. Cobb values and pyrolysis gas chromatography-mass spectrom-etry (Py-GCMS) results show that size reversion is not a simple oxidation. The oxidation reaction was found to be significantly light dependent. Temperature variations were found to have moderate effect on the chemical stability.