Abstract: Polymer blends suitable for packaging are disclosed that include one or more impact modifiers; and one or more polyethylene terephthalate homopolymers or copolymers obtained by a melt phase polymerization using a catalyst system comprising aluminum atoms in an amount, for example, from about 3 ppm to about 60 ppm and one or more alkaline earth metal atoms, alkali metal atoms, or alkali compound residues in an amount, for example, from about 1 ppm to about 25 ppm, in each case based on the weight of the one or more polyethylene terephthalate homopolymers or copolymers The polymer blends disclosed exhibit improved low temperature toughness compared with blends made using polymers prepared with conventional catalyst systems.