Process for preparing an aqueous cut of a ligand-free monomer/maleic anhydride polymer and product

A coating composition having improved heat resistance, the coating composition comprising a ligand-free monomer maleic anhydride polymer that is able to be solubilized in an aqueous medium, and an effective amount of a metal ion-containing fugitive ligand complex to solubilize the polymer in the aqueous medium, said aqueous medium having a pH of from 7 to 9, wherein the ligand-free monomer is a polymerizable, ethylenically unsaturated monomer selected from the group consisting of alpha-olefin, aromatic alkenyl monomer, acrylate monomer, methacrylate monomer, and combinations thereof, wherein the metal ion of the metal ion-containing fugitive ligand complex is a zinc or zirconium ion, and wherein the fugitive ligand is ammonia.