Adhesion promoted block copolyester composition with multi-functional carboxylic compound

Method of preparing an adhesion-modified thermoplastic hot melt adhesive composition which comprises blending in molten form, based on the total thermoplastic components,

• (A) 1 to 99 percent by weight of a solid thermoplastic segmented copolyester elastomer consisting essentially of a multiplicity of recurring short chain ester units and long chain ester units joined through ester linkages, said short chain ester units amounting to 15 to 75 percent by weight of said copolyester and being of the formula:
• ##STR22## and said long chain ester units amounting to 25 to 85 percent by weight of said copolyester and being of the formula:
• ##STR23## where R is the divalent radical remaining after removal of the carboxyl groups from a dicarboxylic acid having a molecular weight of less than 350, D is the divalent radical remaining after removal of the hydroxyl groups from organic diol having a molcular weight of less than 250, and G is the divalent radical remaining after removal of the terminal hydroxyl groups from long chain glycol having an average molecular weight of 350 to 6000, said copolyester having a melt index of less than 150 and a melting point of at least 90.degree. C.,
• (B) 1 to 99 percent by weight of a solid low molecular weight thermoplastic resin which forms compatible mixtures with the segmented copolyester, is thermally stable at 150.degree. C., and has a melt viscosity of less than 10,000 centipoises at 200.degree. C., modified with (C) 0.3 to 8.0 parts by weight, per 100 parts by weight of elastomer (A) and resin (B), of a functional carboxylic compound taken from the group consisting of aromatic and aliphatic anhydrides having at least two anhydride groups.