US Patent 7932345 Aluminum containing polyester polymers having low acetaldehyde generation rates

A polyester polymer composition containing polyester polymers such as polymers having repeating ethylene terephthalate units, aluminum atoms in an amount of at least 3 ppm based on the weight of the polymer, the polyester polymers having an It.V. of at least 0.72 dL/g obtained through a melt phase polymerization and a residual acetaldehyde level of 10 ppm or less. Also provided are polyester polymer compositions containing polyester polymers and:(i) aluminum atoms(ii) alkaline earth metal atoms or alkali metal atoms or alkali compound residues, and(iii) a catalyst deactivator such as a phosphorus compound. The phosphorus compound is added to the polyester melt either late in the polycondensation or upon remelting a solid polyester polymer. The polyester polymer exhibits good L* brightness, clarity, and low levels of acetaldehyde generated upon melting.