The present invention relates to a dispersant polymer and a dispersion containing the dispersant polymer. The dispersant polymer is derived from a polyamine species reacted with two different polyester chains, one of which includes a monomeric repeat unit derived from the polyesterification reaction of lactide, glycolide, lactic acid, or glycolic acid monomers. The technology includes preparing the dispersant polymer at lower temperature to allow the use of a broader selection of polyester repeat units.