A pH buffer is a solution that helps maintain a stable pH level by resisting changes in acidity or alkalinity. pH buffers contain a weak acid and its conjugate base or a weak base and its conjugate acid, and are used to regulate pH in a variety of applications, including chemical analysis, industrial processes, and biological systems. The buffering action of a pH buffer is accomplished by the weak acid or base accepting or donating hydrogen ions as needed to counteract changes in the pH caused by other substances added to the solution.
In the esterification process of starch using octenyl-succinic anhydride, a pH buffer such as sodium hydroxide or sodium carbonate is used to maintain a neutral pH during the reaction. The purpose of the pH buffer is to keep the pH of the reaction mixture stable, which is important for ensuring that the reaction progresses as desired. This helps to prevent the formation of unwanted byproducts and ensures that the final product has the desired properties and characteristics.