AROMATIC POLYESTER OF HIGH TERMINAL-CARBOXYL GROUP CONTENT AND ITS PRODUCTION

摘要

PURPOSE:To obtain an aromatic polyester having a high terminal-carboxyl group content and excellent reactivity, by reacting a molten aromatic polyester of a limiting viscosity of at least a specified value with a dicarboxylic acid in a specified weight ratio. CONSTITUTION:A molten aromatic polyester having a limiting viscosity =0.2 [measured at 35 deg.C in a tetrachloroethanephenol (4:6) solvent ] is mixed with x% dicarboxylic acid of formula I , wherein R is a 10-18C alkylene or substituted alkylene, e.g., dodecanedicarboxylic acid or ethyltetradecanedicarboxylic acid). Here, x satisfies the conditions of relationship II, wherein MD is the MW of the dicarboxylic acid of formula I , and [eta] is the limiting viscosity of the polyester after the addition of the dicarboxylic acid. The mixture is then reacted to obtain an aromatic polyester of a high terminal-carboxyl group content.