Improved method for rosin esterification.

摘要

The catalytic combination of phosphinic acid (also called hypophosphorous acid) and a phenol sulfide compound is disclosed to accelerate the reaction rate of esterification of rosin with a polyhydric alcohol, as well as provide product color improvements. According to the process of the invention, a rosin is reacted with up to a 50% equivalent excess of the polyhydric alcohol in the presence of phosphinic acid and a phenol sulfide compound at a temperature of from about 180 DEG C to about 300 DEG C.