To manufacture an article having improved low-temperature impact strength, especially a thin-walled article for use as a dual-ovenable tray.

This article is manufactured by thermoforming a polymer blend which comprises (a) 86-98 wt.% polyethylene terephthalate having an intrinsic viscosity of at least 0.7 dL/g, (b) 1-7 wt.% polyethylene ionomer and (c) 1-7 wt.% polyolefin having repeat units derived from 2-6C olefin monomer, wherein the polymer blend contains an effective amount of a heat stabilizer. The thermoforming of the polymer blend is carried out in a heated mold over a period of time sufficient to achieve a crystallinity of 10-40%.