An acid-functional polymer is reacted with a transition metal compound having an average particle size small enough to react with the polymer at a temperature below the glass transition temperature of the polymer, e.g., at room temperature, to produce cross-linked polymer. The process produces a liquid polymer product that dries to a cross-linked film without the required presence of volatile ligands. Improved coatings such as floor polishes that can be formed from these cross-linked polymers are also disclosed.