FOERBAETTRAT FOERFARANDE FOER FOERESTRING AV HARTS

摘要

The invention relates to an improved method for esterification of a resin with a polyhydric alcohol, in which the resin and the polyhydric alcohol are heated in the presence of a catalytic amount of phosphinic acid (also called hypophosphoric acid) and a phenol sulphide compound in an inert environment. The resin is preferably reacted with up to a 50% equivalent excess of the polyhydric alcohol in the presence of the phosphinic acid and the phenol sulphide compound at a temperature of about 180-300 degree C.