There is now provided a polyester polymer particle having an It.V., a
surface, and a center, wherein the It.V. at the surface of the particle
is less than 0.25 dL/g higher than the It.V. at the center of the
particle. The polyester polymer particle is desirably crystalline to
prevent the particles from sticking to each other while drying, and
desirably contains less than 10 ppm acetaldehyde. A polyester container,
preferably a preform or beverage bottle, is made by feeding crystallized
polyester particles having an It.V. of at least 0.70 dL/g to an extrusion
zone, melting the particles in the extrusion zone to form a molten
polyester polymer composition, and forming a sheet or a molded part from
extruded molten polyester polymer, wherein at least a portion of the
polyester particles have an It.V. at their surface which does not vary
from their It.V. at their center by more than 0.25 dL/g, and the
particles have not been solid state polymerized. Such polyester
compositions have an It.V. suitable for containers, yet lose less It.V.
during melt processing than existing polyesters.