Abstract: There is described a method for the production of a functional polyester having functional group X. The method comprises the step of melt blending a composition comprising (i) a high number average molecular weight (Mn) polyester having a Mn of ?6,000 Da; and (ii) a functional compound comprising functional group Y which may be the same as functional group X or be different to functional group X but be operable to form functional group X in the functional polyester. The composition is melt blended such that the high Mn polyester and the functional compound react to produce the functional polyester. The high Mn polyester has a Mn that is higher than the Mn of the functional compound. The present invention extends to functional polyesters produced by the method; aqueous, solventborne and powder coating compositions containing the functional polyester, and articles coated with the said coating compositions.

Abstract: Copolyesters comprising monomeric units derived from norbornane compounds such as 2,3-norbornane dicarboxylic acid anhydride or dicarboxylate exhibit amorphous characteristics. Exemplary copolymers are obtained by polycondensation of ethylene glycol, terephthalic acid, and up to about 40 mole % cis-norbornane-endo-2,3-dicarboxylic acid anhydride or dimethyl trans-norbornane 2,3-dicarboxylate or mixtures thereof, based upon the total moles of ester forming components of the polyester. The copolymers containing monomeric units derived from norbornane dicarboxylic acid or dicarboxylate can be obtained by melt polymerization and exhibit no or very low crystallinity. The copolyesters may be used to produce transparent, optically clear amorphous articles of manufacture such as containers, extruded objects, and packaging by melt processing techniques such as injection molding, blow molding, extrusion or thermoforming.